Monday, January 19, 2009

Bose-Einstein Condensate Refracting Telescopes

With their ability to slow down light by 100 million or more times, does this mean that Bose-Einstein Condensates have very high refractive indexes and therefore excellent for telescope use?

By: Vanessa Uy

Though not yet mentioned - as far as I know - throughout Star Trek’s 40 or so years of history, just imagine a substance with the ability to slow down light from 300 million meters per second to 3 meters per second – the speed of a little girl riding a bike. With a substance like this, can we ever make the ultimate refracting telescope – i.e. the kind that uses lenses to magnify far away objects – using this substance as our lens?

For about 8 years or so, scientists have been experimenting with Bose-Einstein Condensate and had been observing their property of being able to slow down the speed of light as it passes through them by a factor of 100 million – even a little bit more in subsequent laboratory experiments. Given this kind of refractive index, which since hitherto we can only dream of, will we be soon making astronomical telescopes using Bose-Einstein Condensate for the lenses?

Currently, Bose-Einstein Condensates are still seen as mere “laboratory curiosity”. But since lab experiments have shown that given their ability to slow down light, Bose-Einstein Condensates certainly have refractive indexes several order of magnitudes greater than the ophthalmology-grade glass – which is 35% lead to increase it’s refractive index - currently used as optical lenses in telescope construction. Even the refractive index of diamond lenses – even if you can afford to use one – still pales in comparison to a lens constructed out of Bose-Einstein Condensate.

The higher the refractive index means the smaller or more compact you can make your telescope compared to one made using lenses with a lower refractive index, even if both of them are rated with the same powers of magnification. Looks like Bose-Einstein Condensates will have their first practical use in the field of astronomy. But if Bose-Einstein Condensates are a miracle material when it comes to refracting telescope construction, how come nobody has built one yet?

Using present technology, Bose-Einstein Condensates exists only in temperatures very near to that of absolute zero. It would be very impractical to construct a Bose-Einstein Condensate telescope the size of a Soviet-era RPG-7 with magnification ability comparable to that of the Keck telescope in Hawaii. When it’s cooling system – to maintain the structural integrity of the Bose-Einstein Condensate lenses – is the size of St. Paul’s Cathedral.

Given the somewhat “rapid” advances in technology, a Bose-Einstein Condensate astronomical telescope could be built – someday. Remember back in the 1980’s where 12-bit digital video processing and CCD or charge coupled device cameras with peak quantum efficiencies approaching 85% can only be found in US National Security Agency reconnaissance satellites. Today 12-bit digital video processing is now de rigeur in DVD players – even those made in China. And high quantum efficiency CCD cameras can be easily bought in better specialist astronomy shops at prices from 200 to 1,000 US dollars each – which is nigh on impossible to purchase during the Reagan Administration. Plus those bolometer-on-a-chip helmet-mounted thermal-imaging cameras used by firefighters that used to cost 6,000 dollars 15 years ago can now even be bought for less than the hundred dollars in some garage sales and swap meets.

Technological advances always mean a quantum leap in performance coupled by a dramatic reduction in price and widespread ability. Who knows that 200 years from now, telescopes made from room temperature Bose-Einstein Condensate lenses will be widely available, even to middle-school kids. Too bad Gene Roddenberry haven’t built one for Captain James T. Kirk in the original series of Star Trek.

Wednesday, January 14, 2009

Thomas Harriet: The First to Use the Telescope in Astronomy?

There is now proof that an Englishman from Oxford named Thomas Harriet was the first to use the then newly invented telescope in stargazing a few months before Galileo. Will our schoolbooks be revised?

By: Vanessa Uy

In a debacle somewhat reminiscent of the late 1970’s debate on who were the first to release the first Punk single – The Sex Pistols or The Damned? - Has now invaded the world of astronomy. And the timing that even supermarket tabloids can only dream of, given that we are just starting the UN-declared International Year of Astronomy in honor of the Galileo being the first to use the then newly invented device called the telescope in astronomy on that fateful night in 1609. Will this story be the forever remembered as the bombshell of the 2009 International Year of Astronomy?

The recently discovered document – according to the BBC World report aired on January 14, 2009 proves that the Oxford gentleman-scientist named Thomas Harriet (or is it spelled Harriett?) had beat the Italian polymath named Galileo in being the first to use the then newly invented device called the telescope in stargazing / astronomy. The newly found document focuses on the detailed drawings and sketches used by Thomas Harriet in his attempt to map the mountains on the Moon and to record on what he saw on his telescope near the end of December 1608.

Being a gentleman of stature in 17th Century Oxford, Thomas Harriet probably procrastinated in taking steps to publish his recent findings because he has other more important tings to do. Or because it would take almost superhuman-like feats to publish such groundbreaking and radical scientific findings in an age almost 400 years before the invention of the Internet, never mind Blogging and Web 2.0. Given these preexisting challenges of publishing ones own extremely groundbreaking scientific discoveries during 17th Century Europe, it's easy for both Thomas Harriett and Galileo to be ignorant of each others findings even years after their own lifetimes. But first let us review the a piece of equipment that both of them used to advance the then fledgling science of astronomy - namely the telescope.

The telescope - according to most Europeans at that time - was the product of Dutch spectacle-makers. These Dutch spectacle-makers who had been grinding lenses from chunks of glass - probably since Medieval Times - did so without fully understanding quite how they worked. A few years after 1600, one of them, possibly a Dutch scientists named Hans Lippershey. Discovered by happy accident that two lenses of appropriate curvature, held the proper distance apart, makes distant objects look larger. Galileo was the first - as we know so far - to put the fascinating invention to serious work in astronomy. But was he really the only one who did it during that time?

Given that Galileo was the first to publish his findings, he established the principal claim. Which sadly also draws the attention of the Pan-European Inquisition and the 17th Century Vatican Police Apparatus to the detriment of Galileo’s future standing in the scientific community of 17th Century Italy.

Back to the mountains on the Moon issue, dispute was arising fast over who should take credit for these glorious new discoveries hitherto never seen before the telescope was pointed to the heavens. Even though Galileo was very much aware of the dilemma between the urge to publish his findings quickly, and the need for continued observations until he was certain of their accuracy. Galileo chose to publish his findings immediately, thus was forever credited for being the first one to use the telescope as an astronomical instrument. Even though a gentleman from Oxford, England named Thomas Harriet had beat him to it by several months.

Sunday, January 11, 2009

My 2009 International Year of Astronomy Wish Lists

Even tough we are primarily honoring Galileo’s pioneering efforts in his use of the telescope in astronomy, we all can still wish for very interesting celestial phenomena this 2009 can’t we?

By: Vanessa Uy

Yes it was primitive, but have you ever wondered why no one before Galileo ever decided out of curiosity to use 15th Century era telescopes for stargazing and astronomical purposes before that fateful night back in 1609? We could be honoring Galileo out of his sheer luck 400 years later, but given his resolve against the genocidal bureaucratic might of the Inquisition, he really does deserve the honor.

Suppose we amateur stargazers and amateur astronomers can make a wish list about very interesting celestial / astronomical phenomena to occur that could make the night skies of 2009 the most interesting of the last 400 years. What would it be? For the sheer fun of it, how about a very bright supernova that could put the supernova of 1987 – Supernova 1987A – into shame? Though the supernova should occur not too close to our system to allow it to blow away the Earth’s ozone layer. Otherwise, a very bright supernova would be perfect.

Scores of comets would also be a good choice. Especially ones that rival the size and brightness magnitude of the comet Hyakutake’s appearance back in 1996, or what about the appearance of an oddly shaped comet? Like the Arend-Roland Comet of 1956. Or for an ultimate year-end finale, our large bright comet’s occultation with our very bright supernova during the Yuletide Season of 2009 just to make things more festive given the global economic downturn would still be around by then.

Those previously mentioned are probably the only ones that are of immediate concern to us amateur astronomers. Given the capabilities of the telescopes that we immediately possess. Those who are into astronomy as their day jobs could discover more fascinating and exotic astronomical phenomena this 2009. Like new extra-solar planets the size of our Earth for instance. Or what about new Kuiper Belt objects whose properties allow yet again the International Astronomical Union’s reevaluation of Pluto’s status as a bona fide planet.

Yep, those pesky little Kuiper Belt objects that had recently become the wildcards when it comes to Pluto’s status as a planet. Which to me is always good news, given that astronomy has always been ruminating in its complacent obscurity (in Uranus?). A controversy that allows it further mainstream-media exposure – even supermarket tabloid-style exposure – is always good for astronomy.

Remembering Henrietta Swan Leavitt

Is our contemporary astronomical community very reluctant to honor the achievements of Miss Henrietta Swan Leavitt because it could reveal the very recent chauvinistic past of astronomy?

By: Vanessa Uy

Her mathematical works in astronomy were frequently rumored to have helped in the eventual discovery of the planet Pluto in 1930. But American astronomer Henrietta Swan Levitt (1868 – 1921) was better known in the astronomical community for her discovery of the relation between the absolute magnitudes of Cepheid variable stars and the periods of their light-variations. Which later provided as a method for “sounding” the depths of our cosmos. She is also credited with the discovery of a number of asteroids, four novas, and 2,400 variable stars.

Around 1912 – i.e. during the early years of stellar spectroscopy - particularly at the Harvard Astronomical Observatory, almost all of the data were catalogued and analyzed by female astronomers – called “computers” – who were forbidden because of their gender / sex to use the telescopes. It is quite ironic that during the “Dark Ages” – i.e. in the early 20th Century’s chauvinist-leaning sociological period of modern astronomy - that the work of such female astronomers as Henrietta Swan Leavitt and Annie Jump Cannon (1863 – 1941) came to be of greater significance. Especially when compared to the work of many of their male colleagues who saw these female astronomers to be nothing more than menial assistants.

Back in 1912, Miss Henrietta Swan Leavitt, an assistant at Harvard Astronomical Observatory had been assigned the task of studying 25 Cepheid variable stars in the Small Magellanic Cloud. Without any prior idea of the remoteness of the stars she was investigating, she noticed a peculiar characteristic that had since made all variable stars famous: The brighter they are, the more slowly they fluctuate. Miss Leavitt thought her find rather peculiar and published it. At once, because of her discovery, the great Danish astronomer at that time Ejnar Hertzprung – co-discoverer with Princeton’s H. N. Russel of the color-brightness graph and of the difference between dwarf and giant stars – took serious notice. The two of them soon realized that Miss Leavitt’s curious discovery might be the key to measuring the vast distances of the universe.

Before Henrietta Swan Leavitt’s discovery of Cepheid variable stars’ brightness fluctuations, astronomers previously used the geometric method of parallax in their attempts of measuring the vastness of our universe. Parallax is the apparent movement of stars, or in actuality a reflection of the Earth’s motion as viewed against the background of more distant stars. But parallax has one glaring drawback when used to measure the almost incomprehensible vastness of our universe. When measuring distances of 500 light-years and beyond, our base angle with respect of the diameter of the “circle” – actually it is an ellipse of low eccentricity - defining the Earth’s orbital path around the Sun could fall ridiculously low. When our base angle of parallax falls below 0.006 second, parallax as a means of geometrically measuring the vast distances of the universe becomes essentially useless.

This is where the beauty and brilliance of Henrietta Swan Leavitt’s discovery of using Cepheid variables to measure the vast distances of our universe comes into it’s own. If astronomers can see the distant galaxies and their retinue of Cepheid variables, those astronomers can measure how far away that galaxy is with certainty hitherto unobtainable previously via geometric parallax. Just imagine using geometric parallax to measure the distance of our nearest galactic neighbor, the Andromeda Galaxy. The parallax triangle that results in measuring the Great Galaxy of Andromeda’s 2 million or so light-year distance from us would look for all intents and purposes nothing more than a virtually straight line.

The 2009 International Year of Astronomy: Galileo Rem

Primarily a commemoration of that fateful night back in 1609 when Galileo first used a telescope in astronomy, but has our contemporary society come a long way since the Inquisition?

By: Vanessa Uy

When Galileo turned his “primitive” telescope to the night sky on that fateful night back in 1609, he never expected in his wildest dreams the wondrous vistas he had opened which people at that time had hardly dreamed were there. Galileo found mountains on the Moon; he soon found out that Venus had Moon-like phases, which proved the planet’s Sun-centered orbit. And also the four “little stars” orbiting Jupiter, which were later named collectively as the “Galilean Satellites” in Galileo’s honor; the countless stars never before seen in the main band of the Milky Way, plus the Sunspots traversing the solar disk which made him deduce that the Sun rotates. With all these discoveries, in one fell swoop, the old, comforting idea of the planet Earth being the center of creation was doomed 400 years ago.

Armed with these findings, Galileo became a convinced Copernican – i.e. the Earth and the rest of the planet’s revolving around the Sun, unlike the Church accepted Earth-centered Ptolemaic system – which spurred him into a “crusade” to gain Church acceptance of the Copernican system. But the bureaucracy of the Roman Catholic Church at that time proved unyielding and even threatened to unleash the might of the Inquisition on Galileo. Which eventually coerced him to admit “errors” in order to avoid torture - all proved to be in vain to still Galileo’s questioning mind and his faith in God.

Now 400 years after that fateful night when Galileo decided to use the relatively primitive telescopes of the time for stargazing, the 2009 International Year of Astronomy should – in my opinion – be dedicated to Galileo’s resolve in the face of the “evil” bureaucracy of the Roman Catholic Church. Science shouldn’t be undermined with established power politics, especially when the findings are not to the liking of the powers-that-be. Remember during the height of the Bush Administration when the American ultra-conservative Christian Right decided to make scientific data proving that global warming / climate change is real be labeled a hoax and be made part of their accepted Christian doctrine? Well, America’s ultra-conservative Christian Right almost got away with it because plans to wean-off our dependence on fossil fuels were backlogged for eight years in order for them to maintain their political and financial hegemony - at the expense of our planet’s environment.

Luckily in the nick of time, a more enlightened leader was elected as the new US president in the name of Barack Obama. Economic problems aside, 2009 might yet prove to be a good year for astronomy. Lest we forget what Galileo already experienced first-hand almost 400 years ago that science and politics really are very nasty bedfellows. Which sadly what got Giordano Bruno burned alive at the steak. Maybe the Inquisition is still alive in the 21st Century.