The subject is a perennial favorite at planetarium shows around the world during the Christmas Season. But is there irrefutable proof that the Star of Bethlehem that announced Jesus Christ’s birth is a comet?
By: Vanessa Uy
Though the comet theory of the Star of Bethlehem gained prominence when the Florentine painter Giotto di Bondone painted his “Adoration of the Magi” showing the Star of Bethlehem as a comet. Given that during Giotto’s lifetime that he and his fellow Florentine’s saw one of Halley’s Comet appearance in 1301, the “orientative” (head and tail) structure of a comet could – in theory – serve as a plausible “guiding star” for a precise point on Earth. Thus when Halley’s Comet returned back / made an appearance in 1986, the robotic spacecraft sent to analyze the comet was named Giotto, in honor of the Florentine painter who portrayed the Star of Bethlehem as a comet in his Adoration of the Magi. But does this serve as an irrefutable proof that the Star of Bethlehem is a comet?
The most prominent theory suggesting that the Star of Bethlehem is a comet is the most popular one. The famous Halley’s Comet was visible in 12 BC and was documented on records dating from that period, but other comets observed by stargazers around 5 BC could also be better candidates. Although there’s a problem about the comet theory, given that comets have a long history for being “portents of dire catastrophe” since recorded civilization began. It’s use to signify the fulfilled prophecy heralding the birth of an extremely important person is one nagging detail against the case of the Star of Bethlehem being a comet.
Other much rarer celestial phenomena like supernovae would also seem plausible as a Star of Bethlehem candidate. Archaeological records dating from 5 BC did show that Chinese and Korean stargazers noted observing a nova around that period. Some archeoastronomy scholars even suggest an extremely rare occultation of a periodic comet with that of a super-bright supernova.
Even though we can still see the Crab Nebula – one of the brightest supernova events during the entire human history – via a powerful enough telescope despite the event being completely ignored by European stargazers during the Dark Ages. Finding the supernova remnants of the Star of Bethlehem – if it is indeed a supernova event – will be difficult since ancient stargazers ability to document precise celestial coordinates leaves much to be desired. It wasn’t until Tycho Brahe created gigantic sextants and related instruments like the equatorial armillary that Western astronomy acquired the ability to make and measure “relatively accurate” celestial coordinates that are of use to present day astronomers.
The theory proposing that the Star of Bethlehem is a comet has no trouble being widely accepted because comets are relatively bright celestial occurrences. Most of them can easily exceed the absolute magnitude of the planet Venus as seen on Earth’s surface. Plus their head and tail structure can be interpreted – especially to the ancients – as pointing to a certain direction. Plus, given that the current academic studies suggest that the Three Wise Men in search of Jesus were probably Zoroastrians – i.e. the first adherents of monotheism. And since Zoroastrians see flame as a sacred symbol, Halley’s Comet arriving during the time of Jesus’ birth could suggest that this is a very important event to the Three Wise Men or Magi. Given that photos of Halley’s Comet visitations to our part of the Solar System does make the comet appear flame-shaped, the event will nonetheless seen as an event of auspicious significance, rather that the traditional view of comets being portents of dire catastrophe.
Sunday, December 7, 2008
Monday, November 17, 2008
This Star Belongs to Me?
The heavenly aspirations of having a star or other celestial body named after you usually involve the rigmarole of an earthbound bureaucracy. Too much red tape to achieve celestial immortality?
By: Vanessa Uy
Many of you have asked previously about what it will take to name a star or other celestial body after your loved one or favorite Hollywood celebrity, porn star, musician or band – imagine an Earth-crosser or Earth-crossing asteroid named after Veruca Salt. This particular blog attempts to answer those pressing queries. Spoiler alert: It will cost you ungodly amounts of money.
For quite a while now, an Illinois based company called the International Star Registry – or others like it - had been frequently mentioned in various TV series’ story lines about how someone bought the naming rights of a newly discovered heavenly body after their cherished loved one. Sometimes at a price that’s beyond rational comprehension, imagine purchasing the naming rights of a heavenly body for 3,000 US dollars or more as a Christmas, Valentine’s Day, or Anniversary present as intangible as a celestial body named after you or your special someone.
Sadly, the worldwide astronomical community does not recognize celestial bodies named by the International Star Registry because the company is not the one legally and / or officially tasked to name heavenly bodies. After doing some research about what it takes to have a star or other heavenly and or celestial body named after you and your loved one is a truth that’s really stranger than fiction.
The international body that is assigned the task of naming existing heavenly and or celestial bodies that already exists and those that are yet discovered is the International Astronomical Union or IAU. Over the years, the IAU has been divided into various sub-bodies, teams, committees, and task groups due to the sheer number of celestial bodies that already exists and the ones that are continuously being discovered.
The last time I checked, Dr. Brian G. Marsden director of the IAU ’s Minor Planet Center at the Harvard-Smithsonian Center for Astrophysics in Cambridge is probably one of the busiest of IAU ‘s “top brass”. Because as the head of the Minor Planet Center, asteroids – or minor planets as they are more properly called – is perhaps the celestial body that’s often named after famous and not so famous Hollywood celebrities. Which many tenured astronomers with prestigious university affiliations in the astronomical community often complain because most of these “celebrities” – although there are a few exceptions - haven’t worked in astronomy as an amateur or otherwise or who had no interest in astronomy whatsoever.
But still you can still have a celestial body – preferably an asteroid since there are still many that’s being discovered. To be named after you or your loved one / favorite musician / band / porn star, etc. that the International Astronomical Union will recognize with no strings attached, though it might still cost you several thousands of American currency. You can do this through a “legal loophole” via “research contributions” to professional asteroid hunters – i.e. paying them.
For example, if you have a six-figure sum burning a hole in your pocket – preferably close to a million in American currency, you could contact a professional asteroid hunter like Edward Bowell at the Lowell Observatory in Flagstaff, Arizona. Maybe you might have enough money as research contributions to allow him to bestow some of his yet unnamed newly discovered asteroids with the name of your choice. Like naming an asteroid after your favorite musician or “Rock Band”. Imagine people over 30 will now be forever grateful to you because you spend almost a million in American currency just to name asteroids after Mia Zapata, Lunachicks or Veruca Salt. Sorry to disappoint you guys, but naming asteroids after your favorite musicians, bands, or celebrities do cost ungodly amounts of money. Maybe Adam Carolla’s fans conducted a fundraiser to raise enough money to have his name immortalized in an asteroid. Check out Asteroid 4535 Adamcarolla, it's very faint considering the absolute magnitude that's a little over 12 or so.
By: Vanessa Uy
Many of you have asked previously about what it will take to name a star or other celestial body after your loved one or favorite Hollywood celebrity, porn star, musician or band – imagine an Earth-crosser or Earth-crossing asteroid named after Veruca Salt. This particular blog attempts to answer those pressing queries. Spoiler alert: It will cost you ungodly amounts of money.
For quite a while now, an Illinois based company called the International Star Registry – or others like it - had been frequently mentioned in various TV series’ story lines about how someone bought the naming rights of a newly discovered heavenly body after their cherished loved one. Sometimes at a price that’s beyond rational comprehension, imagine purchasing the naming rights of a heavenly body for 3,000 US dollars or more as a Christmas, Valentine’s Day, or Anniversary present as intangible as a celestial body named after you or your special someone.
Sadly, the worldwide astronomical community does not recognize celestial bodies named by the International Star Registry because the company is not the one legally and / or officially tasked to name heavenly bodies. After doing some research about what it takes to have a star or other heavenly and or celestial body named after you and your loved one is a truth that’s really stranger than fiction.
The international body that is assigned the task of naming existing heavenly and or celestial bodies that already exists and those that are yet discovered is the International Astronomical Union or IAU. Over the years, the IAU has been divided into various sub-bodies, teams, committees, and task groups due to the sheer number of celestial bodies that already exists and the ones that are continuously being discovered.
The last time I checked, Dr. Brian G. Marsden director of the IAU ’s Minor Planet Center at the Harvard-Smithsonian Center for Astrophysics in Cambridge is probably one of the busiest of IAU ‘s “top brass”. Because as the head of the Minor Planet Center, asteroids – or minor planets as they are more properly called – is perhaps the celestial body that’s often named after famous and not so famous Hollywood celebrities. Which many tenured astronomers with prestigious university affiliations in the astronomical community often complain because most of these “celebrities” – although there are a few exceptions - haven’t worked in astronomy as an amateur or otherwise or who had no interest in astronomy whatsoever.
But still you can still have a celestial body – preferably an asteroid since there are still many that’s being discovered. To be named after you or your loved one / favorite musician / band / porn star, etc. that the International Astronomical Union will recognize with no strings attached, though it might still cost you several thousands of American currency. You can do this through a “legal loophole” via “research contributions” to professional asteroid hunters – i.e. paying them.
For example, if you have a six-figure sum burning a hole in your pocket – preferably close to a million in American currency, you could contact a professional asteroid hunter like Edward Bowell at the Lowell Observatory in Flagstaff, Arizona. Maybe you might have enough money as research contributions to allow him to bestow some of his yet unnamed newly discovered asteroids with the name of your choice. Like naming an asteroid after your favorite musician or “Rock Band”. Imagine people over 30 will now be forever grateful to you because you spend almost a million in American currency just to name asteroids after Mia Zapata, Lunachicks or Veruca Salt. Sorry to disappoint you guys, but naming asteroids after your favorite musicians, bands, or celebrities do cost ungodly amounts of money. Maybe Adam Carolla’s fans conducted a fundraiser to raise enough money to have his name immortalized in an asteroid. Check out Asteroid 4535 Adamcarolla, it's very faint considering the absolute magnitude that's a little over 12 or so.
Friday, September 26, 2008
Earth-Crosser Asteroids: Unexamined Threat or Untapped Real Estate?
Ever since the Alvarez’s Brothers proof of an asteroid impact wiping off the dinosaurs became well known, asteroids have since been perceived as the ultimate threat to humanity and civilization. Is it now time to reexamine established assumptions?
By: Vanessa Uy
Earth-crosser asteroids have become inexplicably linked with that 1997 Veruca Salt song “earthcrosser”, which frankly to me passed muster as a depiction to what it would be like to witness first hand a seven-mile wide asteroid crashing down at 50,000 miles per hour just five miles in front of you. Something that’s not so different from what the dinosaurs living in the Yucatan Peninsula witnessed 65 million years ago. It even inspired big budget science fiction movies about what would happen if any of these space-borne high-speed “pieces of dirt” crashes into our planet’s surface at more than seven miles per second.
Earth-crosser asteroids are classified as a Near-Earth asteroid whose orbital path crosses that of the Earth’s regular orbital path. They are different – and a separate group - from Earth-Crossing Asteroids (ECA s) because ECA s are asteroids that are capable of coming very close to Earth at any point in the future and of interest to anyone manning our Spaceguard Survey Program. While Earth-Crosser asteroids, only their orbital path intersects our planet and not the asteroid physically impacting into the Earth’s surface.
Earth-crosser asteroids whose orbital semi-major axes are smaller than Earth’s are classified as Aten asteroids; the remaining ones are classified as Apollo asteroids. Of the Earth-crossing asteroids, 3753 Cruithne is of special interest because it has an orbit that has the same period as that of Earth.
Earth-crosser asteroids have very good uses as potential scientific “space station” sites in the future since their orbits take them to the inner Solar System. Thus serving as a fuel-efficient way of exploring the inner Solar System. Not to mention their potential as a source of valuable ores for the metals needed for our future space faring civilization. Or a good place for research scientists to look for organic materials that remained unchanged since the formation of the Solar System. And the most important of all, real estate for setting up colonies either for long-term studies on space colonization or just good platforms to build our future astronomical labs on.
To colonize these asteroids is probably the best way to study their motions across our Solar System and researchers on an asteroid are probably the ones who can readily obtain data. Like weather their particular asteroid they are sitting on will crash into our planet somewhere in the distant future. They can probably obtain a very exact if and when compared to their “Earthbound” counterparts.
But Earth-crosser asteroids need extensive developing to make them habitable to humans. Like the construction of pressure domes with appropriate radiation shielding from the Sun’s harmful radiation and of cosmic rays as well. Earth-crosser asteroids are very different from Earth when it comes to their surface conditions unlike the way they are portrayed in 1950’s era science fiction films. Some of them have even less surface gravity than our Moon because they are much smaller in size. But their development holds a myriad of promise for mankind.
By: Vanessa Uy
Earth-crosser asteroids have become inexplicably linked with that 1997 Veruca Salt song “earthcrosser”, which frankly to me passed muster as a depiction to what it would be like to witness first hand a seven-mile wide asteroid crashing down at 50,000 miles per hour just five miles in front of you. Something that’s not so different from what the dinosaurs living in the Yucatan Peninsula witnessed 65 million years ago. It even inspired big budget science fiction movies about what would happen if any of these space-borne high-speed “pieces of dirt” crashes into our planet’s surface at more than seven miles per second.
Earth-crosser asteroids are classified as a Near-Earth asteroid whose orbital path crosses that of the Earth’s regular orbital path. They are different – and a separate group - from Earth-Crossing Asteroids (ECA s) because ECA s are asteroids that are capable of coming very close to Earth at any point in the future and of interest to anyone manning our Spaceguard Survey Program. While Earth-Crosser asteroids, only their orbital path intersects our planet and not the asteroid physically impacting into the Earth’s surface.
Earth-crosser asteroids whose orbital semi-major axes are smaller than Earth’s are classified as Aten asteroids; the remaining ones are classified as Apollo asteroids. Of the Earth-crossing asteroids, 3753 Cruithne is of special interest because it has an orbit that has the same period as that of Earth.
Earth-crosser asteroids have very good uses as potential scientific “space station” sites in the future since their orbits take them to the inner Solar System. Thus serving as a fuel-efficient way of exploring the inner Solar System. Not to mention their potential as a source of valuable ores for the metals needed for our future space faring civilization. Or a good place for research scientists to look for organic materials that remained unchanged since the formation of the Solar System. And the most important of all, real estate for setting up colonies either for long-term studies on space colonization or just good platforms to build our future astronomical labs on.
To colonize these asteroids is probably the best way to study their motions across our Solar System and researchers on an asteroid are probably the ones who can readily obtain data. Like weather their particular asteroid they are sitting on will crash into our planet somewhere in the distant future. They can probably obtain a very exact if and when compared to their “Earthbound” counterparts.
But Earth-crosser asteroids need extensive developing to make them habitable to humans. Like the construction of pressure domes with appropriate radiation shielding from the Sun’s harmful radiation and of cosmic rays as well. Earth-crosser asteroids are very different from Earth when it comes to their surface conditions unlike the way they are portrayed in 1950’s era science fiction films. Some of them have even less surface gravity than our Moon because they are much smaller in size. But their development holds a myriad of promise for mankind.
Friday, August 29, 2008
Mecca Mean Time: A New Way To Measure Our Planet?
Muslim scientists and clerics call for the adoption of Mecca Mean Time throughout the Islamic world during the April 21, 2008 conference in the Gulf State of Qatar gained widespread press coverage. How will the Western world react?
By: Vanessa Uy
As the world’s major news providers surprisingly (to me at least) bothered to cover the “Mecca, the Center of the Earth, Theory and Practice” conference in the Gulf State of Qatar back in April 21, 2008. The purpose of the conference is to spread the word throughout the Islamic World about Muslim scientists and clerics calling for the adoption of Mecca Mean Time to replace GMT – at least in the Islamic World. Arguing that the Saudi City of Mecca is the true center of the Earth. A prominent cleric and a leading voice of the conference in Qatar, Sheik Youssef al-Qaradawy, said that modern science had at last provided evidence that Mecca was the true center of the Earth. Proof, the cleric said, of the greatness of the Muslim “Qibla” – the Arabic word for the direction Muslims turn to when they pray.
The meeting in the Gulf State of Qatar is part of an increasingly popular trend in Muslim Societies increasingly being assimilated by the Western World’s modernistic materialism of seeking to find Koranic precedents for modern science. Not surprising for us in the know since it was Arabic scholars who studied in the learning centers of 12th Century Andalucia, Spain who had sown the tentative seeds of the Renaissance, especially in the planet Earth measuring science of geodesy. Even the 9th Century Arab mathematician named al-Khowarizmi briefly enjoyed fame outside of the stuffy old academic circle towards the end of April 2008.
Unfortunately, majority of the scientists in the libertine West – especially astronomers; make that American astronomers – became very weary. And they immediately voiced their weariness in the Blogosphere. Philip Plate’s Bad Astronomy website serves as a very excellent example. Despite of the somewhat emotionally heavy-handed reaction by most of us “defenders of rationality” here in the West, we have our reasons. Mostly it relates to the Inquisition and the burning alive of Giordano Bruno on the steak or the “reclusion perpetua” of Galileo by the “Princes of the Vatican. But it is rather more recent. And it happened in the school district of Dover, Pennsylvania back in 2004.
A re-labeled form of Creationism called Intelligent Design was almost re-introduced into the Dover, Pennsylvania school district by Nazi-inspired practitioners of an extremist form of Christianity. Fortunately, Judge John E. Jones was wise enough to decide that the false-yet-profitable doctrine of Intelligent Design doesn’t belong in US public schools. Many legal precedents in the US Supreme Court’s docket, like the Supreme Court ruling on Edwards v. Aguillard back in 1987 serves as a guiding light. After all, if they – the misguided right-wing Christian extremists - want to learn Creationism / Intelligent Design, they can always go to Richard Butler’s Aryan Nation headquarters in Hayden Lake, Idaho. Given that our embrace of an egalitarian and pluralistic society had made the Western World resilient enough to overcome the threat posed by Nazi-inspired forms of Christianity, why do a majority of Western scientists very much against the idea of a Mecca Mean Time? After all, it’s only for Muslims?
Maybe (90%sure) it’s because we Western Internet-savvy smart-asses with MENSA I.Q. ’s always view with equal tragedy the destruction of the giant Buddha statues in Bamian, Afghanistan by the Taliban. To that of the September 11, 2001 terrorist attacks on the World Trade Center Towers by misguided extremists under the auspices of Osama Bin Laden’s Al-Qaeda. And the rift between Islam and the West only gets wider if we postpone an inter-cultural dialogue pertaining to the issue of Mecca Mean Time. Despite frequenting various Board of Muftis-approved Halal restaurants, I’ve yet to experience some Muslim intellectual talking to us X-Files / Dead Heads (Grateful Dead fans) / Trekkies / occasional Junoon fans about the “411” on Mecca Mean Time, Instead of just reading about it on the Internet. Most of all, my fellow Trekkies don’t have the levels of Islamophobia manifested by US President George W. Bush’s Neo-Conservatives.
But the Western world is not entirely of the hook. If we – the supposedly enlightened West – has allowed other existing cultures to develop into a space-faring society, it would not only be a boon to cultural anthropologists, but also to us “ amateur rocket scientists types” to know how they did it. Especially on which way their “steam gauges” turn – clockwise or counter-clockwise? Imagine this, what if the Zulu Tribe of South Africa is allowed to become a space-faring civilization. Since they are located way below the Earth’s equator, they would design their clocks to move “counter-clockwise” relative to ours since this is how their sundials – as observed by them through time – move. So does the “steam gauges” – i.e. instrumentation indicators on their spacecraft might move different from us who grew up above the Earth’s equator. We won’t have to go light-years into deep space to study cultural phenomena such as this.
Sadly, I’m not the emperor of the world. Mecca Mean Time will probably wind up into one of those good ideas that never got off the ground – both literally and figuratively. And this will surely reinforce many a Muslim scholar on how Western Civilization yet again is ungrateful for the wealth of knowledge provided by Arabic scholars who used to frequent the centers of learning in 12th Century Andalucia, Spain. For without this intellectual collaboration, the European Renaissance could not have happened. It looks like a Mecca Mean Time-based geodesy will never get under scrutiny - even an extensive peer review - by Western scientists.
By: Vanessa Uy
As the world’s major news providers surprisingly (to me at least) bothered to cover the “Mecca, the Center of the Earth, Theory and Practice” conference in the Gulf State of Qatar back in April 21, 2008. The purpose of the conference is to spread the word throughout the Islamic World about Muslim scientists and clerics calling for the adoption of Mecca Mean Time to replace GMT – at least in the Islamic World. Arguing that the Saudi City of Mecca is the true center of the Earth. A prominent cleric and a leading voice of the conference in Qatar, Sheik Youssef al-Qaradawy, said that modern science had at last provided evidence that Mecca was the true center of the Earth. Proof, the cleric said, of the greatness of the Muslim “Qibla” – the Arabic word for the direction Muslims turn to when they pray.
The meeting in the Gulf State of Qatar is part of an increasingly popular trend in Muslim Societies increasingly being assimilated by the Western World’s modernistic materialism of seeking to find Koranic precedents for modern science. Not surprising for us in the know since it was Arabic scholars who studied in the learning centers of 12th Century Andalucia, Spain who had sown the tentative seeds of the Renaissance, especially in the planet Earth measuring science of geodesy. Even the 9th Century Arab mathematician named al-Khowarizmi briefly enjoyed fame outside of the stuffy old academic circle towards the end of April 2008.
Unfortunately, majority of the scientists in the libertine West – especially astronomers; make that American astronomers – became very weary. And they immediately voiced their weariness in the Blogosphere. Philip Plate’s Bad Astronomy website serves as a very excellent example. Despite of the somewhat emotionally heavy-handed reaction by most of us “defenders of rationality” here in the West, we have our reasons. Mostly it relates to the Inquisition and the burning alive of Giordano Bruno on the steak or the “reclusion perpetua” of Galileo by the “Princes of the Vatican. But it is rather more recent. And it happened in the school district of Dover, Pennsylvania back in 2004.
A re-labeled form of Creationism called Intelligent Design was almost re-introduced into the Dover, Pennsylvania school district by Nazi-inspired practitioners of an extremist form of Christianity. Fortunately, Judge John E. Jones was wise enough to decide that the false-yet-profitable doctrine of Intelligent Design doesn’t belong in US public schools. Many legal precedents in the US Supreme Court’s docket, like the Supreme Court ruling on Edwards v. Aguillard back in 1987 serves as a guiding light. After all, if they – the misguided right-wing Christian extremists - want to learn Creationism / Intelligent Design, they can always go to Richard Butler’s Aryan Nation headquarters in Hayden Lake, Idaho. Given that our embrace of an egalitarian and pluralistic society had made the Western World resilient enough to overcome the threat posed by Nazi-inspired forms of Christianity, why do a majority of Western scientists very much against the idea of a Mecca Mean Time? After all, it’s only for Muslims?
Maybe (90%sure) it’s because we Western Internet-savvy smart-asses with MENSA I.Q. ’s always view with equal tragedy the destruction of the giant Buddha statues in Bamian, Afghanistan by the Taliban. To that of the September 11, 2001 terrorist attacks on the World Trade Center Towers by misguided extremists under the auspices of Osama Bin Laden’s Al-Qaeda. And the rift between Islam and the West only gets wider if we postpone an inter-cultural dialogue pertaining to the issue of Mecca Mean Time. Despite frequenting various Board of Muftis-approved Halal restaurants, I’ve yet to experience some Muslim intellectual talking to us X-Files / Dead Heads (Grateful Dead fans) / Trekkies / occasional Junoon fans about the “411” on Mecca Mean Time, Instead of just reading about it on the Internet. Most of all, my fellow Trekkies don’t have the levels of Islamophobia manifested by US President George W. Bush’s Neo-Conservatives.
But the Western world is not entirely of the hook. If we – the supposedly enlightened West – has allowed other existing cultures to develop into a space-faring society, it would not only be a boon to cultural anthropologists, but also to us “ amateur rocket scientists types” to know how they did it. Especially on which way their “steam gauges” turn – clockwise or counter-clockwise? Imagine this, what if the Zulu Tribe of South Africa is allowed to become a space-faring civilization. Since they are located way below the Earth’s equator, they would design their clocks to move “counter-clockwise” relative to ours since this is how their sundials – as observed by them through time – move. So does the “steam gauges” – i.e. instrumentation indicators on their spacecraft might move different from us who grew up above the Earth’s equator. We won’t have to go light-years into deep space to study cultural phenomena such as this.
Sadly, I’m not the emperor of the world. Mecca Mean Time will probably wind up into one of those good ideas that never got off the ground – both literally and figuratively. And this will surely reinforce many a Muslim scholar on how Western Civilization yet again is ungrateful for the wealth of knowledge provided by Arabic scholars who used to frequent the centers of learning in 12th Century Andalucia, Spain. For without this intellectual collaboration, the European Renaissance could not have happened. It looks like a Mecca Mean Time-based geodesy will never get under scrutiny - even an extensive peer review - by Western scientists.
Friday, May 16, 2008
Is the Asteroid Vesta a Planet?
Since the dethronement of Pluto as a planet by the International Astronomical Union due to the planet being just like the countless other Kuiper Belt fragments seems somewhat disheartening. Must we clamor for another replacement?
By: Vanessa Uy
Ever since the search of planets far beyond Saturn i.e. far beyond what our naked eye can see had started a technological race to build a bigger - and therefore better – astronomical telescope towards the end of the 18th Century. Though it enabled William Herschel to discover the planet Uranus, this technological race allowed the discovery of a yet unknown region of our Solar System that’s much closer to home. A region that lies the orbit between the planet Mars and the planet Jupiter - namely the Asteroid Belt.
On the first night of the 19th Century, Giuseppe Piazzari discovered the largest of the known asteroids. He christened it Ceres after the ancient Roman goddess of agriculture. Later measurements have shown that the asteroid Ceres has a diameter of 440 miles or 710 kilometers with a surface area of 700,000 square miles or 1,810,000 square kilometers. Other asteroids were discovered in quick succession like Pallas – named after on what the Roman’s referred to as Athena – with a diameter of 300 miles or 480 kilometers. Then came Vesta – named after the Roman goddess of hearth fire – with a diameter of 240 miles or 385 kilometers. And then Juno – named after the queen of heaven in Roman mythology – with a diameter of 120 miles or 195 kilometers. Ceres, Pallas, Vesta, and Juno were often referred to as the “Big Four” of the asteroids because they are the only ones with substantial size. This title not only made these asteroids to assume a roughly spherical shape due to the substantial gravity created by their sheer mass concentration, but also those other asteroid bodies are very small in comparison to form a meaningful numerical ratio.
Though only the third largest of the “Big Four” asteroids, Vesta is the only one of them that can be seen on the Earth’s surface via the naked eye. To wonder why ancient “stargazers” who came scores of centuries before – even Renaissance era astronomers - failed to notice and observe the asteroid Vesta is a 250-page doctoral dissertation subject-in-itself. But the not so cut-and-dried scientific data that defines this asteroid only deepens its own mystery.
A number of people who do astronomy for a living have been intrigued by the subsequent scientific data that pertains to the somewhat quirky “geologic” history of the asteroid Vesta. Compared to other asteroids, the way Vesta evolved i.e. the history of how volcanic basalt migrated to Vesta’s surface and cooled is similar to how our planet Earth evolved through the eons. Ben Zellner, an astronomer at Georgia Southern University, is a proponent of the view that the asteroid Vesta should be considered as a planet in light of its geologic history. Zellner says that: “Early on, it (the asteroid Vesta) went through the same kind of history that the Earth and other rocky planets went through.” Zellner and his colleagues even utilized data from the Hubble Space Telescope back in March of 1995 to create a detailed and updated map of the surface of Vesta. Their Hubble data showed a type of basalt that cools below the surface being exposed by recent – geologically speaking – giant meteorite impacts. One such impact, in fact, is believed to have flung pieces of Vesta flying toward Earth. The different types of basalt that they have observed, says Zellner, only serve to confirm their suspicions that Vesta – though now frozen solid – must once have had a structure similar to the planet Earth, replete with a crust, mantle, and a molten liquid core.
Even if Vesta won’t be declared as a new planet, it doesn’t stand to loose brownie points - as one of the most interesting pieces of real estate in our Solar System. Asteroids are perfect spots for setting up laboratories to explore substances that date back to the formation of our Solar System. It is also a very good place to set up space based astronomical observatories, just think how our planet Earth will look when viewed by a 30 power telescope on Vesta’s surface. It also has a potential use as a future mining colony given that we are running out of profitable ores in which to mine our metals, or to provide as springboards for excursions deeper into the remote corners of the Solar System. The immediate future of mankind has always been part and parcel on our willingness to explore and develop the richest found in these asteroids.
By: Vanessa Uy
Ever since the search of planets far beyond Saturn i.e. far beyond what our naked eye can see had started a technological race to build a bigger - and therefore better – astronomical telescope towards the end of the 18th Century. Though it enabled William Herschel to discover the planet Uranus, this technological race allowed the discovery of a yet unknown region of our Solar System that’s much closer to home. A region that lies the orbit between the planet Mars and the planet Jupiter - namely the Asteroid Belt.
On the first night of the 19th Century, Giuseppe Piazzari discovered the largest of the known asteroids. He christened it Ceres after the ancient Roman goddess of agriculture. Later measurements have shown that the asteroid Ceres has a diameter of 440 miles or 710 kilometers with a surface area of 700,000 square miles or 1,810,000 square kilometers. Other asteroids were discovered in quick succession like Pallas – named after on what the Roman’s referred to as Athena – with a diameter of 300 miles or 480 kilometers. Then came Vesta – named after the Roman goddess of hearth fire – with a diameter of 240 miles or 385 kilometers. And then Juno – named after the queen of heaven in Roman mythology – with a diameter of 120 miles or 195 kilometers. Ceres, Pallas, Vesta, and Juno were often referred to as the “Big Four” of the asteroids because they are the only ones with substantial size. This title not only made these asteroids to assume a roughly spherical shape due to the substantial gravity created by their sheer mass concentration, but also those other asteroid bodies are very small in comparison to form a meaningful numerical ratio.
Though only the third largest of the “Big Four” asteroids, Vesta is the only one of them that can be seen on the Earth’s surface via the naked eye. To wonder why ancient “stargazers” who came scores of centuries before – even Renaissance era astronomers - failed to notice and observe the asteroid Vesta is a 250-page doctoral dissertation subject-in-itself. But the not so cut-and-dried scientific data that defines this asteroid only deepens its own mystery.
A number of people who do astronomy for a living have been intrigued by the subsequent scientific data that pertains to the somewhat quirky “geologic” history of the asteroid Vesta. Compared to other asteroids, the way Vesta evolved i.e. the history of how volcanic basalt migrated to Vesta’s surface and cooled is similar to how our planet Earth evolved through the eons. Ben Zellner, an astronomer at Georgia Southern University, is a proponent of the view that the asteroid Vesta should be considered as a planet in light of its geologic history. Zellner says that: “Early on, it (the asteroid Vesta) went through the same kind of history that the Earth and other rocky planets went through.” Zellner and his colleagues even utilized data from the Hubble Space Telescope back in March of 1995 to create a detailed and updated map of the surface of Vesta. Their Hubble data showed a type of basalt that cools below the surface being exposed by recent – geologically speaking – giant meteorite impacts. One such impact, in fact, is believed to have flung pieces of Vesta flying toward Earth. The different types of basalt that they have observed, says Zellner, only serve to confirm their suspicions that Vesta – though now frozen solid – must once have had a structure similar to the planet Earth, replete with a crust, mantle, and a molten liquid core.
Even if Vesta won’t be declared as a new planet, it doesn’t stand to loose brownie points - as one of the most interesting pieces of real estate in our Solar System. Asteroids are perfect spots for setting up laboratories to explore substances that date back to the formation of our Solar System. It is also a very good place to set up space based astronomical observatories, just think how our planet Earth will look when viewed by a 30 power telescope on Vesta’s surface. It also has a potential use as a future mining colony given that we are running out of profitable ores in which to mine our metals, or to provide as springboards for excursions deeper into the remote corners of the Solar System. The immediate future of mankind has always been part and parcel on our willingness to explore and develop the richest found in these asteroids.
Friday, April 4, 2008
In Search of Planet Vulcan
Astronomers used to believe that there is a planet closer to the Sun than Mercury that affected the planet’s orbit before Einstein’s “General Relativity Theory” made such a planet’s existence unnecessary. Many years on, does planet Vulcan really doesn’t exist?
By: Vanessa Uy
Back in the day’s when astronomers used to believe that Kepler’s Laws of Planetary Motion are part and parcel of Newtonian Physics, astronomers were at a loss in explaining on as to what have caused the advancing perihelion of the planet Mercury’s orbit around the Sun. Then came French astronomer Urbain Jean Joseph Leverrier, who’s prior fame included correctly predicted the existence of planet Neptune in 1846. Through his calculations based on the orbital irregularities of the planet Uranus’ orbit years before Neptune’s existence is proven by being seen through a telescope, Leverrier also theorized that the planet Mercury’s advancing perihelion was caused by a henceforth yet undiscovered planet. Leverrier dubbed the unknown planet Vulcan after the Roman god of volcanoes probably due to its closeness to the Sun and therefore having a very hot surface.
But as time went on, our recently updated knowledge of the natural world necessitates the reevaluation of what we’ve known before. According to Kepler’s laws, the planets move in ellipses, with the Sun near one common focus. This is not exactly the prediction of Newtonian theory. The planets, in addition to being attracted by the Sun, also attract each other, although to a lesser extent since their individual masses are much less than that of the Sun. If these small mutual perturbations are taken into account, then the accurately observed planetary motions agree closely with the predictions of the Newtonian theory, except in a few small particulars. The most notorious and most accurately observed discrepancy between theory and observation is the so-called advancing perihelion or perihelion motion of the planet Mercury.
Perihelion is the point of closest approach of a planet to the Sun. On account of the perturbations by other planets, the perihelion position changes slightly with each passage of the planet around its respective orbit. However, the observed perihelion motion of the planet Mercury has been known since the 19th Century to be much larger compared to the figure predicted by the Newtonian theory by 42 seconds of an arc per century. Quite small, but observable nonetheless.
Various explanations were put fourth, including the theoretical existence – some say in the astronomical community as “invention” – of an intra-Mercurial planet named Vulcan. Some even proposes the modification of Newton’s Law of Universal Gravitation which for all intents and purposes seem like a return to the days when the Catholic Church labeled the Copernican model of the Solar System as a “fiction convenient for calculation”. But each proposal produced fresh conflicts with observation. Albert Einstein was able to show that the additional perihelion motion was predicted directly by his theory without any further assumption. And the discovery of a particular solution of his equation – which is more commonly known as the Schwarzschild solution – made even more direct and elegant calculations possible, that lead to the correct prediction.
By about 1950, a corresponding but much smaller correction to the motion of the planet Earth’s perihelion – which is also predicted by Einstein’s theory – had been established by observation. In the case of the other planets, the effect is too small to have been observed thus far. Looks like this effect is much easier to observe near the Sun’s gravity well. Latter theories say the perturbations of Earth crossing asteroids is sufficient to explain the perihelion motion without resorting to the yet proven General Relativity of Einstein. Some even talk about the presence of “dark matter” in our solar system caused the perihelion motion. To me, all of these are enough to make every astronomer’s “day job” extremely interesting.
Despite it’s existence being continuously endangered by Einstein’s General Relativity theory, the planet Vulcan being theorized by Urbain Jean Joseph Leverrier steadfastly refuses to die out. Planet Vulcan even gained a new lease of life in the years after World War II during which it infiltrated the science fiction literate pop culture of America. There’s an episode in the original Star Trek back in the 1960’s where Captain Kirk and his Science Officer Spock must “beam in” a US Air Force pilot after their tractor beam “accidentally” wrecked his F-104 Starfighter. As the American airman inquired about Spock’s homeworld, he told Captain Kirk that planet Vulcan just lies beyond the planet Mercury. Even in the mid-1960’s, the existence of Leverrier’s planet Vulcan is more or less common knowledge despite Einstein’s General Relativity relegating it to the mythical realm.
But in the mid-1990’s, the credence of planet Vulcan’s existence gained a renaissance when amateur astronomers armed with appropriate telescopes saw “chunks of rock” other than the planet Mercury transiting the Sun. But later, those rocks were later proven to be just asteroids whose highly elliptical orbits bring them closer to the Sun than Mercury. Though some of them concluded that Vulcan therefore exists as opposed to some faraway planet created by the mind of Gene Roddenberry.
By: Vanessa Uy
Back in the day’s when astronomers used to believe that Kepler’s Laws of Planetary Motion are part and parcel of Newtonian Physics, astronomers were at a loss in explaining on as to what have caused the advancing perihelion of the planet Mercury’s orbit around the Sun. Then came French astronomer Urbain Jean Joseph Leverrier, who’s prior fame included correctly predicted the existence of planet Neptune in 1846. Through his calculations based on the orbital irregularities of the planet Uranus’ orbit years before Neptune’s existence is proven by being seen through a telescope, Leverrier also theorized that the planet Mercury’s advancing perihelion was caused by a henceforth yet undiscovered planet. Leverrier dubbed the unknown planet Vulcan after the Roman god of volcanoes probably due to its closeness to the Sun and therefore having a very hot surface.
But as time went on, our recently updated knowledge of the natural world necessitates the reevaluation of what we’ve known before. According to Kepler’s laws, the planets move in ellipses, with the Sun near one common focus. This is not exactly the prediction of Newtonian theory. The planets, in addition to being attracted by the Sun, also attract each other, although to a lesser extent since their individual masses are much less than that of the Sun. If these small mutual perturbations are taken into account, then the accurately observed planetary motions agree closely with the predictions of the Newtonian theory, except in a few small particulars. The most notorious and most accurately observed discrepancy between theory and observation is the so-called advancing perihelion or perihelion motion of the planet Mercury.
Perihelion is the point of closest approach of a planet to the Sun. On account of the perturbations by other planets, the perihelion position changes slightly with each passage of the planet around its respective orbit. However, the observed perihelion motion of the planet Mercury has been known since the 19th Century to be much larger compared to the figure predicted by the Newtonian theory by 42 seconds of an arc per century. Quite small, but observable nonetheless.
Various explanations were put fourth, including the theoretical existence – some say in the astronomical community as “invention” – of an intra-Mercurial planet named Vulcan. Some even proposes the modification of Newton’s Law of Universal Gravitation which for all intents and purposes seem like a return to the days when the Catholic Church labeled the Copernican model of the Solar System as a “fiction convenient for calculation”. But each proposal produced fresh conflicts with observation. Albert Einstein was able to show that the additional perihelion motion was predicted directly by his theory without any further assumption. And the discovery of a particular solution of his equation – which is more commonly known as the Schwarzschild solution – made even more direct and elegant calculations possible, that lead to the correct prediction.
By about 1950, a corresponding but much smaller correction to the motion of the planet Earth’s perihelion – which is also predicted by Einstein’s theory – had been established by observation. In the case of the other planets, the effect is too small to have been observed thus far. Looks like this effect is much easier to observe near the Sun’s gravity well. Latter theories say the perturbations of Earth crossing asteroids is sufficient to explain the perihelion motion without resorting to the yet proven General Relativity of Einstein. Some even talk about the presence of “dark matter” in our solar system caused the perihelion motion. To me, all of these are enough to make every astronomer’s “day job” extremely interesting.
Despite it’s existence being continuously endangered by Einstein’s General Relativity theory, the planet Vulcan being theorized by Urbain Jean Joseph Leverrier steadfastly refuses to die out. Planet Vulcan even gained a new lease of life in the years after World War II during which it infiltrated the science fiction literate pop culture of America. There’s an episode in the original Star Trek back in the 1960’s where Captain Kirk and his Science Officer Spock must “beam in” a US Air Force pilot after their tractor beam “accidentally” wrecked his F-104 Starfighter. As the American airman inquired about Spock’s homeworld, he told Captain Kirk that planet Vulcan just lies beyond the planet Mercury. Even in the mid-1960’s, the existence of Leverrier’s planet Vulcan is more or less common knowledge despite Einstein’s General Relativity relegating it to the mythical realm.
But in the mid-1990’s, the credence of planet Vulcan’s existence gained a renaissance when amateur astronomers armed with appropriate telescopes saw “chunks of rock” other than the planet Mercury transiting the Sun. But later, those rocks were later proven to be just asteroids whose highly elliptical orbits bring them closer to the Sun than Mercury. Though some of them concluded that Vulcan therefore exists as opposed to some faraway planet created by the mind of Gene Roddenberry.
Wednesday, March 26, 2008
A Backpacker’s Guide to Mercury
Even though the planet is not very far from Earth, Mercury will not be an easy place to view through a telescope – even visit – due to its closeness to our Sun. Will this be a problem to future travel agencies?
By: Vanessa Uy
Our Solar System’s smallest and innermost planet, Mercury, has been - for ages – proved notoriously difficult for Earth – based astronomical observation. This piece of rock, with a diameter of 3,030 miles (4,800 km.) is hardly bigger than our Moon (2,160 miles). Mercury is also not that far from Earth, sometimes coming in as near as 48,337,000 miles and it is fairly bright when viewed from ground level.
The main reason that makes the planet Mercury so difficult to Earth-based observers is the planet’s closeness to our Sun. Thus the angle between Mercury (which appears as a fairly bright star when viewed by our naked eye at ground level) and our Sun is always less than that between the two hands of a watch at 1 o’clock. This “quirk of geometry” makes itself known every time you try to observe the planet Mercury at daytime, the Sun’s blazing light complicates optical – based observation of the planet, and when nighttime comes, the planet disappears from view almost as quickly as our Sun does. Mercury can be seen alone only when it is low above the horizon, just before sunrise or soon after sunset. Observations at such low angles is seldom satisfactory because of the great distance that the planet Mercury’s light must travel through the Earth’s murky and turbulent lower atmosphere.
Despite the handicaps of Earth-based observations, astronomers were able to measure the rate of rotation of the planet Mercury via Doppler radar. In 1965 the great radio telescope at Arecibo, Puerto Rico, measured the rotation of the planet Mercury by the Doppler shifts of wavelength in radar echoes from its surface. But more sophisticated – and therefore reliable - surface observations of the planet Mercury necessitates the use of unmanned interplanetary probes.
Via Earth – based optical telescopes, planet Mercury always appeared as a nearly featureless blob. Then came the Mariner X (Mariner 10) flybys whose first ever close-up photographs of the planet Mercury’s surface produced an astonished double take among the astronomical community back in 1974. The volumes of data gathered by the Mariner X space probe has the astronomical community concluding back then that the planet Mercury is like our Moon on the outside, but it may well be like the planet Earth on the inside. Like our Moon, the surface of Mercury is pocked with craters and lava-filled basins. But Mariner X also detected an Earth-like magnetic field.
Scientists knew that planetary magnetism was produced by a “dynamo effect” – the rapid rotation of iron-cored planets like the Earth. But planet Mercury rotates far too slow – once in every 58.6 Earth days – for the “dynamo effect” to work. So back in 1974, scientists postulated that a large iron core could also produce magnetism in a slowly rotating body.
The discovery of scarps or cliffs – via the Mariner X’s close-up photographs – towering some two miles high and snake for hundreds of miles through Mercury’s crated regions. These findings made scientists think back in 1974 that these scarps are wrinkles that formed some 4 billion years ago when the planet’s core began to shrink. Which made the planet’s surface crack. Despite the wealth of data collected by the Mariner X spacecraft, the many mysteries surrounding the phenomena that occurs on the planet Mercury necessitates the use of more sophisticated space probes with more advanced instruments in upcoming planetary exploration programs.
Then came the M-Ercury Surface, Space E-Nvironment, G-Eochemistry and Ranging (MESSENGER) probe. The NASA space craft was launched in August 3, 2004 to further study the planet Mercury from orbit to augment the data collected from the Mariner X program that ended back in March 1975. The current MESSENGER mission is the first to visit the planet Mercury in over 30 years. The MESSENGER spacecraft is fitted with the latest generation of scientific instruments that allows it to study from orbit not only the chemical composition of Mercury’s surface. But also the planet’s environment, geologic history, the nature of the magnetic field, the size and state of the core, the volatile inventory at the poles and the nature of Mercury’s exosphere and magnetosphere over a nominal orbital mission of one Earth year.
The current MESSENGER spacecraft has vastly improved optics for improved scanning capability. The cameras supplied to MESSENGER are capable of resolving surface features that are only 18 meters (59 feet) across. A vast improvement compared to the 1.6 kilometers (0.99 miles) resolution of Mariner X. MESSENGER will also be able to image the entire planet as opposed to the previous Mariner X mission which was only able to observe one hemisphere that was lit during the spacecraft’s flyby.
After being launched from a Boeing Delta II rocket, the MESSENGER spacecraft’s travel to the planet Mercury required an extremely large velocity change, or delta-v (known colloquially to aerospace types as “delta vee”), to perform a Hohmann-transfer because Mercury lies deeper in the Sun’s gravity well. A spacecraft travelling to Mercury is greatly accelerated as it falls toward the Sun’s gravity well, so most of the fuel expenditure is used to slow it down to perform a Hohmann-transfer so that the spacecraft can enter Mercury’s orbit.
As MESSENGER’s voyage to the planet Mercury requires extensive use of gravity assists to lower the spacecraft’s fuel expenditure. But this will greatly prolong the time of the trip. And to save rocket fuel even further because there are still no existing refilling stations for hydrazine and nitrogen tetroxide in the spacecraft’s flight path en route to Mercury. The thrust used for insertion into orbit around Mercury will be minimized, resulting in a notably elliptical orbit. Besides the advantage of saving its own propellants, such an orbit allows the MESSENGER spacecraft to measure solar wind and magnetic field strength at various distances from Mercury. Despite of the notably elliptical orbit, the improved instrumentation of MESSENGER can still allow close-up measurements and photographs of Mercury’s surface. As of January 14, 2008, MESSENGER mapped another 30% of Mercury’s surface in addition to the photos taken by Mariner X back in 1974 to 1975. Full orbital insertion of the MESSENGER spacecraft into Mercury will happen in March 18, 2011.
As a follow-up to the MESSENGER mission, the European Space Agency is planning a joint mission with Japan called BepiColombo, which will orbit the planet Mercury with two space probes: one to map the planet and the other one to study the planet’s magnetosphere. The original plan to include a lander has been shelved due to budget constraints and of its dubious scientific value. A Russian Soyuz rocket will launch the “bus” carrying the two probes in 2013 from E.S.A. ’s Guyana Space Center to take advantage of fuel savings when launching from an equatorial location. As with the MESSENGER spacecraft, the BepiColombo “bus” will make close approaches to other planets en route to Mercury for orbit-changing / Hohmann-transfer gravitational assists. The BepiColombo “bus” will first fly past our Moon then to the planet Venus and making several approaches to the planet Mercury before entering orbit.
By: Vanessa Uy
Our Solar System’s smallest and innermost planet, Mercury, has been - for ages – proved notoriously difficult for Earth – based astronomical observation. This piece of rock, with a diameter of 3,030 miles (4,800 km.) is hardly bigger than our Moon (2,160 miles). Mercury is also not that far from Earth, sometimes coming in as near as 48,337,000 miles and it is fairly bright when viewed from ground level.
The main reason that makes the planet Mercury so difficult to Earth-based observers is the planet’s closeness to our Sun. Thus the angle between Mercury (which appears as a fairly bright star when viewed by our naked eye at ground level) and our Sun is always less than that between the two hands of a watch at 1 o’clock. This “quirk of geometry” makes itself known every time you try to observe the planet Mercury at daytime, the Sun’s blazing light complicates optical – based observation of the planet, and when nighttime comes, the planet disappears from view almost as quickly as our Sun does. Mercury can be seen alone only when it is low above the horizon, just before sunrise or soon after sunset. Observations at such low angles is seldom satisfactory because of the great distance that the planet Mercury’s light must travel through the Earth’s murky and turbulent lower atmosphere.
Despite the handicaps of Earth-based observations, astronomers were able to measure the rate of rotation of the planet Mercury via Doppler radar. In 1965 the great radio telescope at Arecibo, Puerto Rico, measured the rotation of the planet Mercury by the Doppler shifts of wavelength in radar echoes from its surface. But more sophisticated – and therefore reliable - surface observations of the planet Mercury necessitates the use of unmanned interplanetary probes.
Via Earth – based optical telescopes, planet Mercury always appeared as a nearly featureless blob. Then came the Mariner X (Mariner 10) flybys whose first ever close-up photographs of the planet Mercury’s surface produced an astonished double take among the astronomical community back in 1974. The volumes of data gathered by the Mariner X space probe has the astronomical community concluding back then that the planet Mercury is like our Moon on the outside, but it may well be like the planet Earth on the inside. Like our Moon, the surface of Mercury is pocked with craters and lava-filled basins. But Mariner X also detected an Earth-like magnetic field.
Scientists knew that planetary magnetism was produced by a “dynamo effect” – the rapid rotation of iron-cored planets like the Earth. But planet Mercury rotates far too slow – once in every 58.6 Earth days – for the “dynamo effect” to work. So back in 1974, scientists postulated that a large iron core could also produce magnetism in a slowly rotating body.
The discovery of scarps or cliffs – via the Mariner X’s close-up photographs – towering some two miles high and snake for hundreds of miles through Mercury’s crated regions. These findings made scientists think back in 1974 that these scarps are wrinkles that formed some 4 billion years ago when the planet’s core began to shrink. Which made the planet’s surface crack. Despite the wealth of data collected by the Mariner X spacecraft, the many mysteries surrounding the phenomena that occurs on the planet Mercury necessitates the use of more sophisticated space probes with more advanced instruments in upcoming planetary exploration programs.
Then came the M-Ercury Surface, Space E-Nvironment, G-Eochemistry and Ranging (MESSENGER) probe. The NASA space craft was launched in August 3, 2004 to further study the planet Mercury from orbit to augment the data collected from the Mariner X program that ended back in March 1975. The current MESSENGER mission is the first to visit the planet Mercury in over 30 years. The MESSENGER spacecraft is fitted with the latest generation of scientific instruments that allows it to study from orbit not only the chemical composition of Mercury’s surface. But also the planet’s environment, geologic history, the nature of the magnetic field, the size and state of the core, the volatile inventory at the poles and the nature of Mercury’s exosphere and magnetosphere over a nominal orbital mission of one Earth year.
The current MESSENGER spacecraft has vastly improved optics for improved scanning capability. The cameras supplied to MESSENGER are capable of resolving surface features that are only 18 meters (59 feet) across. A vast improvement compared to the 1.6 kilometers (0.99 miles) resolution of Mariner X. MESSENGER will also be able to image the entire planet as opposed to the previous Mariner X mission which was only able to observe one hemisphere that was lit during the spacecraft’s flyby.
After being launched from a Boeing Delta II rocket, the MESSENGER spacecraft’s travel to the planet Mercury required an extremely large velocity change, or delta-v (known colloquially to aerospace types as “delta vee”), to perform a Hohmann-transfer because Mercury lies deeper in the Sun’s gravity well. A spacecraft travelling to Mercury is greatly accelerated as it falls toward the Sun’s gravity well, so most of the fuel expenditure is used to slow it down to perform a Hohmann-transfer so that the spacecraft can enter Mercury’s orbit.
As MESSENGER’s voyage to the planet Mercury requires extensive use of gravity assists to lower the spacecraft’s fuel expenditure. But this will greatly prolong the time of the trip. And to save rocket fuel even further because there are still no existing refilling stations for hydrazine and nitrogen tetroxide in the spacecraft’s flight path en route to Mercury. The thrust used for insertion into orbit around Mercury will be minimized, resulting in a notably elliptical orbit. Besides the advantage of saving its own propellants, such an orbit allows the MESSENGER spacecraft to measure solar wind and magnetic field strength at various distances from Mercury. Despite of the notably elliptical orbit, the improved instrumentation of MESSENGER can still allow close-up measurements and photographs of Mercury’s surface. As of January 14, 2008, MESSENGER mapped another 30% of Mercury’s surface in addition to the photos taken by Mariner X back in 1974 to 1975. Full orbital insertion of the MESSENGER spacecraft into Mercury will happen in March 18, 2011.
As a follow-up to the MESSENGER mission, the European Space Agency is planning a joint mission with Japan called BepiColombo, which will orbit the planet Mercury with two space probes: one to map the planet and the other one to study the planet’s magnetosphere. The original plan to include a lander has been shelved due to budget constraints and of its dubious scientific value. A Russian Soyuz rocket will launch the “bus” carrying the two probes in 2013 from E.S.A. ’s Guyana Space Center to take advantage of fuel savings when launching from an equatorial location. As with the MESSENGER spacecraft, the BepiColombo “bus” will make close approaches to other planets en route to Mercury for orbit-changing / Hohmann-transfer gravitational assists. The BepiColombo “bus” will first fly past our Moon then to the planet Venus and making several approaches to the planet Mercury before entering orbit.
Tuesday, February 26, 2008
Is SETI a Dead End Search?
Is the SETI program doomed to fail because no sentient being claiming to be intelligent chooses radio – waves as a means of communicating over vast interstellar distances?
By: Vanessa Uy
Ever since humanity mastered the efficient propagation of radio - waves early in the 20th Century and formalized the science of radio astronomy. We became intrigued by the prospect that somewhere out there in space there might be extraterrestrial - beings. Beings that are as smart or smarter - than - us just waiting for our hails. Given the vast distance separating the stars, and on what we’ve learned on how fast radio – waves can travel, it seems like calling out to our interstellar brethren might be a fools errand. Yet it haven’t discouraged a group of astronomers from establishing SETI, which stands for the Search for Extra Terrestrial Intelligence.
Radio – waves are a part of the electromagnetic spectrum which includes the visible light part of the spectrum - which allows us to see the world around us plus the other parts that we use everyday. Like the ultra violet rays from the sun that allows our skin to produce Vitamin D and an “aesthetically pleasing” tan. Like the X – Rays for non-invasive medical analysis, the near – infrared which operates our TVs remote, the longer infrared which we use to cook and heat our food, to microwaves used in microwave ovens and navigation purposes. Then the radio – waves of various frequencies used for navigation, telecommunication, or just produced as a by product of grid electricity production (the 60 Hz AC current produces radio – waves whose wavelengths measures about 3,000 Km from crest to crest).
Radio – waves travel in space at about 186,000 miles per second or 300,000 kilometers per second. Given the vastness of space radio – waves sent to the Moon will reach there in just 1.25 seconds, Mars in about 20 minutes while further on into the Gas Giants, it could be more than an hour. Radio – waves will take almost ten hours to reach Pluto and will take the whole part of the day to completely leave our Solar System past the Kuiper Belt and the Oort Cloud regions. Four and a quarter years to reach Alpha Centauri, 150,000 years to go across the Milky Way galaxy and will probably take 18 billion years to go across the known universe. You probably now starting to get the idea of the problem faced in interstellar communication using just radio – waves. Imagine sending an e – mail to your ET friend who lives 45 light years away from you and chances are you won’t get a response within your lifetime.
Despite the problems there are solutions even though they may take a “few years” depending on how much of our government funds slated for scientific research will be diverted to a “War on Terror” rife with malfeasance. There’s that experiment done by Albert Einstein, Boris Podolsky and Nathan Rosen about quantum entanglement. The results of which have not yet been utilized for practical applications after all these years. Then there’s the phenomenon of particles that travel faster – than – light like tachyons, or what about the concept of “wormholes” or an “Einstein – Rosen Bridge”. The list goes on and who knows you might be the lucky one to develop such technology like the one used in the Star Trek TV series called subspace communication technology.
Despite “sticking their guns” on radio – wave technology that’s limited by the 186,000 miles–per-second speed limit, the current SETI is by no means astronomy’s white elephant. Back in the 1970’s, SETI received an anomalous signal in which they dubbed as the “WOW Signal” because it’s the definitive “smoking gun” if you will of an extraterrestrial civilization possessing technology to modulate a radio – wave for the purposes of telecommunication. Despite the ensuing excitement, the “WOW Signal” was never found again even after all these years. But anyone of us who still believes still live in hope that someday ET will call back.
To me, using radio – waves to search for extraterrestrial intelligence across the vastness of the cosmos is somewhat an inelegant solution. This will be like our ancient ancestors choosing to attach flotation devices on their feet to walk across vast stretches of water as opposed to inventing / building boats and ships. And also – to me – the search for extraterrestrial intelligence is somewhat of a misnomer. Using “radio telescopes” for SETI purposes will only detect “extraterrestrial technology”, don’t forget that extraterrestrial sentient beings that are technological equals to our ancient Babylonian astronomers are intelligent too.
By: Vanessa Uy
Ever since humanity mastered the efficient propagation of radio - waves early in the 20th Century and formalized the science of radio astronomy. We became intrigued by the prospect that somewhere out there in space there might be extraterrestrial - beings. Beings that are as smart or smarter - than - us just waiting for our hails. Given the vast distance separating the stars, and on what we’ve learned on how fast radio – waves can travel, it seems like calling out to our interstellar brethren might be a fools errand. Yet it haven’t discouraged a group of astronomers from establishing SETI, which stands for the Search for Extra Terrestrial Intelligence.
Radio – waves are a part of the electromagnetic spectrum which includes the visible light part of the spectrum - which allows us to see the world around us plus the other parts that we use everyday. Like the ultra violet rays from the sun that allows our skin to produce Vitamin D and an “aesthetically pleasing” tan. Like the X – Rays for non-invasive medical analysis, the near – infrared which operates our TVs remote, the longer infrared which we use to cook and heat our food, to microwaves used in microwave ovens and navigation purposes. Then the radio – waves of various frequencies used for navigation, telecommunication, or just produced as a by product of grid electricity production (the 60 Hz AC current produces radio – waves whose wavelengths measures about 3,000 Km from crest to crest).
Radio – waves travel in space at about 186,000 miles per second or 300,000 kilometers per second. Given the vastness of space radio – waves sent to the Moon will reach there in just 1.25 seconds, Mars in about 20 minutes while further on into the Gas Giants, it could be more than an hour. Radio – waves will take almost ten hours to reach Pluto and will take the whole part of the day to completely leave our Solar System past the Kuiper Belt and the Oort Cloud regions. Four and a quarter years to reach Alpha Centauri, 150,000 years to go across the Milky Way galaxy and will probably take 18 billion years to go across the known universe. You probably now starting to get the idea of the problem faced in interstellar communication using just radio – waves. Imagine sending an e – mail to your ET friend who lives 45 light years away from you and chances are you won’t get a response within your lifetime.
Despite the problems there are solutions even though they may take a “few years” depending on how much of our government funds slated for scientific research will be diverted to a “War on Terror” rife with malfeasance. There’s that experiment done by Albert Einstein, Boris Podolsky and Nathan Rosen about quantum entanglement. The results of which have not yet been utilized for practical applications after all these years. Then there’s the phenomenon of particles that travel faster – than – light like tachyons, or what about the concept of “wormholes” or an “Einstein – Rosen Bridge”. The list goes on and who knows you might be the lucky one to develop such technology like the one used in the Star Trek TV series called subspace communication technology.
Despite “sticking their guns” on radio – wave technology that’s limited by the 186,000 miles–per-second speed limit, the current SETI is by no means astronomy’s white elephant. Back in the 1970’s, SETI received an anomalous signal in which they dubbed as the “WOW Signal” because it’s the definitive “smoking gun” if you will of an extraterrestrial civilization possessing technology to modulate a radio – wave for the purposes of telecommunication. Despite the ensuing excitement, the “WOW Signal” was never found again even after all these years. But anyone of us who still believes still live in hope that someday ET will call back.
To me, using radio – waves to search for extraterrestrial intelligence across the vastness of the cosmos is somewhat an inelegant solution. This will be like our ancient ancestors choosing to attach flotation devices on their feet to walk across vast stretches of water as opposed to inventing / building boats and ships. And also – to me – the search for extraterrestrial intelligence is somewhat of a misnomer. Using “radio telescopes” for SETI purposes will only detect “extraterrestrial technology”, don’t forget that extraterrestrial sentient beings that are technological equals to our ancient Babylonian astronomers are intelligent too.
Sunday, January 6, 2008
Pluto No Longer a Planet
The astronomical community’s consensus to reclassify Pluto’s status as a planet will have repercussions that won’t easily die down.
By: Vanessa Uy
That’s right, Pluto is no longer a planet. Astronomers didn’t have to wait the 248.4 years it takes for Pluto to complete it’s orbit around the sun to reclassify it from a planet to something like one of those large bodies that belong to the Kuiper belt. The Kuiper belt is the region of our solar system where short-period comets originate and this is where material that’s left over from the formation of the planets currently resides.
In 1978, it was found out that Pluto had a moon. The astronomical community named it Charon. Charon is almost the same size as Pluto and this “dumbbell system” has quite a curious effect on Pluto’s angular momentum. Pluto’s highly eccentric orbit will no longer make it as the farthest “planet” from the sun starting 1978. Pluto’s highly eccentric orbit is a consequence of Albert Einstein’s “General Relativity” theory.
By: Vanessa Uy
That’s right, Pluto is no longer a planet. Astronomers didn’t have to wait the 248.4 years it takes for Pluto to complete it’s orbit around the sun to reclassify it from a planet to something like one of those large bodies that belong to the Kuiper belt. The Kuiper belt is the region of our solar system where short-period comets originate and this is where material that’s left over from the formation of the planets currently resides.
In 1978, it was found out that Pluto had a moon. The astronomical community named it Charon. Charon is almost the same size as Pluto and this “dumbbell system” has quite a curious effect on Pluto’s angular momentum. Pluto’s highly eccentric orbit will no longer make it as the farthest “planet” from the sun starting 1978. Pluto’s highly eccentric orbit is a consequence of Albert Einstein’s “General Relativity” theory.
Satellite Gazing: An Alternative to Stargazing?
With the Leonid meteor shower slated for November still a few months away, are artificial satellites worthy targets for amateur astronomers in our increasingly light polluted urban night sky?
By: Vanessa Uy
Orbiting satellites of various shapes and functions had recently become “prime targets” for the starter-kit-astronomical-telescope-owning-amateur-astronomer in today’s increasingly light polluted urban night sky. The satellite’s much higher “relative brightness” rating when compared to other “dimmer” heavenly bodies like the planets Mars and Jupiter make these objects shine out above the orange barf glow permeating your local city’s night sky. Short of doing LASIK surgery on my trusty-but-rusty mass-market Celestron reflector, there’s not much you can do to alleviate the effects of “light pollution” especially if you live with your telescope in an urban area. I’ve read that there are certain people –especially in the United States- who genuinely believe that lighting up 10 million- candle- power street lamps has the power to render any modern assault rifle impotent and obsolete. You might be unknowingly voting for them into your local city council, so please talk sense into them on your spare time. Or send them to downtown Baghdad to test out their policies.
Ever since the launch of Sputnik back in 1957, the number of “space birds” that orbit our planet has been growing steadily. From those that were prime observing targets during their operational lifetimes like SKYLAB and the manned MIR, that had since crashed back to earth to the MIDAS reconnaissance satellites – because of their high orbits- will still be orbiting our planet 20,000 years from now. Unless somebody uses them for target practice via an anti-satellite missile launched from a high performance supersonic jet fighter flying at 90,000 feet or more.
Touted as the 20th Century invention that made the current Internet revolution possible - and since evolved to the real world from the theoretical musings of Arthur C. Clarke, communication satellites are more than just a technological conveyance that allow anyone to surf the web and send e-mails across the globe. To us current generation of satellite gazers / space bird watchers, communication satellites have become a major –if not the most dazzling- part of our observational targets. Like the ever growing family of Iridium satellites whose Teflon-coated high gain antenna reflects the ambient light of the moon and the sun into an optical spectacle that never cease to amaze even the most jaded amateur astronomer.
Orbiting satellites seem to arouse interest to the amateur astronomer’s community with the same enthusiasm as Charles Messier’s catalog of 109 objects. But unlike 18th or 19th Century astronomers (they’re pretty much amateurs back then because anyone who can afford to custom built his own astronomical i.e. really big telescope is automatically an astronomer), amateur astronomers today who chooses “space bird” watching has more than 8,000 –and growing- potential targets for observation. From the International Space Station, shiny Iridium satellites to the somewhat “transient light shows” created by manned space vehicles like the space shuttle whose light displays are always eventful even for the naked eye observer. From the shuttle’s launch into the desired “orbit window” dictated by the specified NASA mission to the shuttle’s brilliant re-entry back into the Earth’s atmosphere, a “light show” that could rival the best Leonid meteor shower of recent memory.
These satellites orbiting Earth has advantage to the novice amateur astronomer / prospective “satellite gazer” – other than their relatively close distance in astronomical terms- is that these objects are highly angular in shape with fine detail in comparison to the moon and other natural heavenly bodies visible in the night sky. With this in mind, you can use their angular and detailed structure as a test bed in computing the Raleigh Criterion i.e. resolution limit of your telescope system. See how it compares to the Canary Island based “Grantecan Telescope.” Or you can test out Wien’s Law or Blackbody Radiation principles in practice, especially if you are fortunate enough to live within driving distance from the company who manufactures the specific satellite you are observing. And if you can, be able to arrange a plant tour to see –and even touch- the satellite’s twin in the plant.
For those who are a genuinely “novice” amateur astronomer, you can check out http://www.heavens-above.com. The user-friendliness of this site is comparable to the latest help desk software. On this site, you can input the latitude and longitude of your observatory i.e. “home” (or is that rooftop) and you can search the heavens-above site for the various “satellites” that can be seen from your home and which part of the night sky you should point your telescope to. The heavens-above.com site is not only limited to observing artificial satellites, you can use the site to “ask” which part of the sky should you point your telescope from your house to see Mars, Jupiter, various stars and Messier objects etc. Also, you can check out the US Space Command’s web site at http://www.spacecom.af.mil/usspace. The US Space Command’s primary mission nowadays is to warn the space shuttle to avoid possible incoming meteor strikes and “space junk.” The US Space Command has the most advanced RADAR array in their Cheyenne Mountain complex that it can even “see” baseball-sized objects whose orbital path could hit the space shuttle. Or for a comprehensive list of satellites in current service, go to NSSDC Master Catalogue Spacecraft Query Form at http://nssdc.gsfc.nasa.gov/nmc/sc-query.html. Also check out the Satellite Tracking Web Page, which is an excellent source of element files and satellite links at http://staff.feldberg.brandeis.edu:80/~progrmer/satellite/satellite.html.
So goodbye and keep on watching the skies.
By: Vanessa Uy
Orbiting satellites of various shapes and functions had recently become “prime targets” for the starter-kit-astronomical-telescope-owning-amateur-astronomer in today’s increasingly light polluted urban night sky. The satellite’s much higher “relative brightness” rating when compared to other “dimmer” heavenly bodies like the planets Mars and Jupiter make these objects shine out above the orange barf glow permeating your local city’s night sky. Short of doing LASIK surgery on my trusty-but-rusty mass-market Celestron reflector, there’s not much you can do to alleviate the effects of “light pollution” especially if you live with your telescope in an urban area. I’ve read that there are certain people –especially in the United States- who genuinely believe that lighting up 10 million- candle- power street lamps has the power to render any modern assault rifle impotent and obsolete. You might be unknowingly voting for them into your local city council, so please talk sense into them on your spare time. Or send them to downtown Baghdad to test out their policies.
Ever since the launch of Sputnik back in 1957, the number of “space birds” that orbit our planet has been growing steadily. From those that were prime observing targets during their operational lifetimes like SKYLAB and the manned MIR, that had since crashed back to earth to the MIDAS reconnaissance satellites – because of their high orbits- will still be orbiting our planet 20,000 years from now. Unless somebody uses them for target practice via an anti-satellite missile launched from a high performance supersonic jet fighter flying at 90,000 feet or more.
Touted as the 20th Century invention that made the current Internet revolution possible - and since evolved to the real world from the theoretical musings of Arthur C. Clarke, communication satellites are more than just a technological conveyance that allow anyone to surf the web and send e-mails across the globe. To us current generation of satellite gazers / space bird watchers, communication satellites have become a major –if not the most dazzling- part of our observational targets. Like the ever growing family of Iridium satellites whose Teflon-coated high gain antenna reflects the ambient light of the moon and the sun into an optical spectacle that never cease to amaze even the most jaded amateur astronomer.
Orbiting satellites seem to arouse interest to the amateur astronomer’s community with the same enthusiasm as Charles Messier’s catalog of 109 objects. But unlike 18th or 19th Century astronomers (they’re pretty much amateurs back then because anyone who can afford to custom built his own astronomical i.e. really big telescope is automatically an astronomer), amateur astronomers today who chooses “space bird” watching has more than 8,000 –and growing- potential targets for observation. From the International Space Station, shiny Iridium satellites to the somewhat “transient light shows” created by manned space vehicles like the space shuttle whose light displays are always eventful even for the naked eye observer. From the shuttle’s launch into the desired “orbit window” dictated by the specified NASA mission to the shuttle’s brilliant re-entry back into the Earth’s atmosphere, a “light show” that could rival the best Leonid meteor shower of recent memory.
These satellites orbiting Earth has advantage to the novice amateur astronomer / prospective “satellite gazer” – other than their relatively close distance in astronomical terms- is that these objects are highly angular in shape with fine detail in comparison to the moon and other natural heavenly bodies visible in the night sky. With this in mind, you can use their angular and detailed structure as a test bed in computing the Raleigh Criterion i.e. resolution limit of your telescope system. See how it compares to the Canary Island based “Grantecan Telescope.” Or you can test out Wien’s Law or Blackbody Radiation principles in practice, especially if you are fortunate enough to live within driving distance from the company who manufactures the specific satellite you are observing. And if you can, be able to arrange a plant tour to see –and even touch- the satellite’s twin in the plant.
For those who are a genuinely “novice” amateur astronomer, you can check out http://www.heavens-above.com. The user-friendliness of this site is comparable to the latest help desk software. On this site, you can input the latitude and longitude of your observatory i.e. “home” (or is that rooftop) and you can search the heavens-above site for the various “satellites” that can be seen from your home and which part of the night sky you should point your telescope to. The heavens-above.com site is not only limited to observing artificial satellites, you can use the site to “ask” which part of the sky should you point your telescope from your house to see Mars, Jupiter, various stars and Messier objects etc. Also, you can check out the US Space Command’s web site at http://www.spacecom.af.mil/usspace. The US Space Command’s primary mission nowadays is to warn the space shuttle to avoid possible incoming meteor strikes and “space junk.” The US Space Command has the most advanced RADAR array in their Cheyenne Mountain complex that it can even “see” baseball-sized objects whose orbital path could hit the space shuttle. Or for a comprehensive list of satellites in current service, go to NSSDC Master Catalogue Spacecraft Query Form at http://nssdc.gsfc.nasa.gov/nmc/sc-query.html. Also check out the Satellite Tracking Web Page, which is an excellent source of element files and satellite links at http://staff.feldberg.brandeis.edu:80/~progrmer/satellite/satellite.html.
So goodbye and keep on watching the skies.
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