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He Has Dragged Us Back Forty Years.

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Showing posts with label astronomy. Show all posts
Showing posts with label astronomy. Show all posts

Thursday, October 24, 2019

CATCHING CRABS Fireworks In The Sky

I love the fourth of July, what with the fireworks and the Sousa Marches, and the flag which, I proudly fly. But there is a tinge of sadness too, because the greatest fireworks display in the sky, at least over the last millennium, occurred on the fourth of July, in the year 1054, and was achieved at an unbelievable cost. On that date, the court astronomer Yang Wei-Te, was shocked to see a new star, what the Chinese called a guest star, blaze into existence, where no star had been visible before.
This new star was reddish-white. It had rays visible streaming from all four corners, and was four times brighter than Venus, which is normally the brightest object in the night sky, besides the moon. This guest star was so bright that it was visible during the day for over three weeks. After that it remained visible at night, although now yellow in color, for three years, until the middle of April, 1057. And then, according to the Chinese, the “guest” faded into obscurity.
The Anasazi Indians of the American desert southwest also noticed the guest star, and recorded it in their rock art and pottery. It is recognized as the same guest star the Chinese saw because the Anasazi pictographs include the new star and the moon. And modern astronomers have calculated that on July 5, 1054, the crescent moon, as seen from North America, would have been just 2 degrees north of where the guest star was seen. Carbon-14 dating of the art indicates it was created about 1060, plus or minus fifteen years. Unfortunately there are no Anasazi left to confirm this story, and, for some reason, no Europeans saw the guest star.
The next time human eyes alighted on this guest star, they belonged to the cheerful English physician and astronomy nut John Bevis, who, in 1731, happened to be looking through a telescope in just the right direction. He had never heard of the Chinese guest star, no European had. But John noted fuzzy “strings of gas and dust” in an empty patch of the constellation Taurus, to the right of the bull’s right horn.
The tip of that horn is in fact a bright star called Aldebaran, an Arabic name which means “the follower”, because Aldebaran seems to follow the Pleides across the sky. The Pleides are a bright point of light that forms the tip of the bull’s other horn. Blevis called his fuzzy patch “M1”, and noted it in a manuscript, complete with drawings that recorded its position in the sky. But John’s publisher went broke, and his book was never published. And poor John died in 1771, when he fell off his telescope. And it looked for awhile as if the guest might escape further notice.
But bits and pieces of John’s manuscript fell into the hands of Charles Messier, a French astronomer who was collecting material for his own star chart, published in 1774. Charles gave full credit for the original observations to poor John, and even used John’s designation of M1,, but it became known as “Messier 1”.
In 1847, another Englishman, the third Earl of Rosse, using a better telescope, drew his own images of John Blevis’ “M1” in Taurus, and decided that it was a nebula (Latin for “cloud”.) He sketched it looking like a crab’s claw. Later, when Rosse could afford a better telescope, he realized that M1 did not look like a crab, but the name stuck. And thus the guest star known as M1 in Taurus, and more commonly became known as the Crab Nebula.
By the early 20th century it was known that the crab was expanding, at something on the order of half of the speed of light (which is about 186,000 miles. or 300,000 kilometers per second). But, of course, as fast as the speed of light is, it still takes light from the crab over 6,000 years to reach the earth, meaning the crab is 6,000 light years away. But people were only beginning to realize how amazing the crab actually was.
Late in the 1950’s a woman attending an open house in the University of Chicago’s telescope approached astronomer Elliot Moore, and told him that the crab appeared, to her, to be flashing. Elliot assured the woman that all stars seemed to twinkle, to which she insisted that as a pilot she knew what stars did, and this one was not twinkling. It was flashing. Elliot dismissed her story, but it turned out that the lady was right, and the astronomer was wrong.
On the night of November 28, 1967 a Scottish Quaker and Cambridge graduate student named Jocelyn Bell Burnell was working with undergraduates when she noticed what she called “scuff” on her radio telescopes’s data printout, indicating a rhythmic, regular and unexpected radio signal. Over eight weeks her team, and her advisor Dr. Anthony Hewish, tried to eliminate all logical sources for this interference, and failed. Could this have been a Jodie Foster “Contact” moment? As a joke, Joycelyn labeled her discovery LGM – 1, for Little Green Men, Source One. Eventually other similar sources of regularly pulsing radio waves were located, originating from other spots in the sky, and the joke was dropped. For practical reasons, the sources were renamed “pulsars”, because they seemed to pulse with energy. In 1974 Dr. Hewish was awarded a Nobel Prize for Jocelyn Bell Burnell’s discovery. She was not slighted because she was a woman, but because she was a graduate student.
It was decided the year after Jocelyn’s discovery, that the pulsars were in fact, neutron stars. The star that exploded to create the guest star in the sky over China in 1054, started out 10 times the size of our sun. After its super nova explosion, what remained was a star, dead center of the crab, just 6 miles in diameter, rotating 30 times a second, or at roughly 4 million miles an hour. That spin creates a huge magnetic field, throwing out 100,000 times the energy thrown out by our own sun, all ripped from the atoms in the space surrounding the pulsar. The energy from the pulsar itself is emitted only in the higher energy parts of the spectrum, above the visual range. Seen by a radio telescope, the pulsar seems to blink on and off, 30 times a second. In fact it is not blinking, but like a light house beacon, it's emitted energy is confined by the neutron star's magnetic fields into narrow pathways, which sweep over our planet 30 times a second, from 6,000 light years away.
So it was, without a doubt, the biggest 4th of July fireworks display in human history, a crashing explosion of  light and an electromagnetic display on a galactic scale. The star that exploded here must have consumed an entire solar system, planets and moons and perhaps even life forms. The bomb must have gone off 6,000 years before the light ever reached us. The ice age was barely over. Humans had barely invented the wheel. We had not yet invented writing. But we would know, eventually, that the light reaching us from the Crab Nebula is emitted by photons passing through heavy elements like carbon, oxygen, nitrogen, and iron. And that is a very disturbing piece of information.
I refuse to believe that an entire solar system was destroyed for our entertainment or edification. Why it was destroyed, if there was a why, we may never know. But we do know that the heavy elements giving color to the Crab Nebula, and to similar nebula across the universe, could only have been produced in a super nova explosion, like the one that was first seen on 4 July 1054.  And those are the heavy elements that make up….us.  And all living things - animals, plants, politicians, pond scum and astronomers, every where in the universe. Whether we know about them or not.
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Monday, January 28, 2019

HALL OF MIRRORS

I think it a profound insight that all telescopes involve mirrors. In 1846 this idea was stumbled upon by the obsessive-compulsive painter Alvan G. Clark, when he realized there was more money to be made in selling  telescopes to rich people than in just painting portraits of rich people. And since both involved selling positive self-images, Alvan dropped his brush and took up the polishing rag. It was said this self taught optician could feel imperfections in the glass lenses through his thumb while polishing them. For over a half a century Alvin and his sons ground magnificent telescopes for rich clients who saw funding observatories as grand monuments to their own intellectual beneficence. Five times Alvin Clark and Sons produced lenses for the largest refraction telescopes in the world. But it is another sad truth that making optical telescopes is an ephemeral art form, since over time all glass lenses tell lies. Even a Clark
One of Alvan Clark's most enthusiastic customers was Mr. Percival Lowell, whose mommy gave him a 2 1/4 inch Clark on his fifteenth birthday. Astronomy was the kind of hobby mother and son could share atop their Brookline mansion. At his father's insistence Percival went into business in Japan (above - the tall one without the hat). But he always returned to his first love; astronomy. And as  the end of the 19th century approached, Percy was attracted by the approach of Mars. 
The more people looked at the red planet, the more it looked like earth. Kepler was the first to realize that Mars was a neighbor of ours. But it was the Dutchman Christiaan Huygens, who drew the first detailed maps of the planet's surface. Then in September of 1877, as the orbits of Earth and Mars converged, Giovanni Schiaparelli used a new telescope and saw what looked like mountain ranges and plains and long mysterious grooves which criss-crossed the planet. He described the grooves in Italian as “canalii”,  a word meaning a channel, or path.  It is sad to point out here, that although Percival Lowell spoke fluent Japanese, he did not speak Italian. 
In 1896, Percival retired from the business world and built his own world class observatory in the mountains, 7,180 feet above Flagstaff, Arizona, atop a peak he named Mars Hill.  Here, for $20,000 (half a million today) Percival installed a 24 inch Clark refracting telescope. Every summer night for the next 23 years, Percival Lowell (above) sat at the bottom of his telescope, observing Mars. During the days he slept in the 24 room mansion he also built on Mars Hill. Being born rich has its advantages, and Percival would have been a fool if he had not taken advantage of his advantages.
And what he saw through the eyepiece of his expensive magical tube was amazing. He saw canals - real canals - more than 180 of them, some of them 4,000 miles long. And he wondered what sort of creatures had constructed such a massive, intricate irrigation system. “Quite possibly, “ he wrote, “such Martian folk are possessed of inventions of which we have not dreamed...Certainly what we see hints at the existence of beings who are in advance of, not behind us, in the journey of life.” 
Percival wrote three books, “Mars”, “Mars and its Canals”, and “Mars as the Abode of :Life”. Each and every book became a best seller. He inspired H.G. Wells to write “War of the Worlds”, as well as inspiring Edgar Rice Burrows, who besides the “Tarzan” series, wrote 13 adventure books centering on Mars. By the year his third book was published, in 1907, Percival Lowell was recognized as the world's expert on the planet Mars. And then, almost over night, Percival's magical red world was deflated by his doppelganger, Mr. George Hale.
George Hale also came from a rich Boston family. But where Percival's father had insisted he attend business school, George's father had sent him to MIT to become a professional astronomer. And in 1908 George opened the lens cap on his new 60” reflector telescope in his new observatory atop California's 5,700 foot high Mount Wilson. And almost the first thing George peered at was Mars, where he found...no canals. Not a one. No matter how hard he looked. It is alleged that George saw an elf in his bedroom, but he saw no canals on Mars.
The photographic proof was conclusive. What Percival had seen as canals proved, when seen through a  newer, bigger, telescope,   to be just an optical illusion, or maybe the blood vessels in the back of Percival's own eye.  Percival had a nervous breakdown. And when he recovered he sought to re-establish his reputation. He took up the search for the the last great mystery in the night sky, the powerful conundrum of Planet X.
According to Percival's own mathematics, there was something very odd about the planets Neptune and Uranus. They were too big, their orbits were odd, Neptune was spinning on its side and they both wobbled. It looked to Percival as as if there had to be another planet further out from the sun, tugging at Uranus and Neptune. He called his suspect Planet X. Percival even calculated Planet X's mass, and he knew exactly where it had to be in the sky, 40 times further out from the sun than the earth.
For ten years Percival and his assistants – okay, mostly his assistants – scoured photographs of the night sky, searching for the tell-tale movement in the star field that would herald the discovery of Planet X. Twice the camera on Percival's 12” Clark took pictures of the moving X.  But the humans who had to examine each one of the thousands of photographs, failed to notice the one dot that had moved slightly. And then,  in 1916, at the age of sixty-one, Percival Lowell suffered a stroke and died. He was buried next to his beloved 12” Clark atop Mars Hill.  But thanks to Percival's fortune, the search for Planet X continued.
In 1930 Clyde Tombaugh found Planet X. And since he was being paid by Percival's endowment, and still using Percival's 12” Clark, Planet X was named using Percival Lowell's initials – PLuto. And isn't it amazing that Planet X became the official IX planet in the solar system? You don't often get to use Roman Numerals in a joke.
Ah, but things were about to get even more amazing. With the refinement of observations of the outer planets a number of new great mysteries appeared in the night sky, as they always do. The more you know the less you know, you know.  You know?
The first thing astronomers realized they did not know was why  two of those three cold blobs of rock and ice circling far out from the Sun– Neptune and Uranus - were so darn massive, too massive to have been formed so far out at the edge of the spinning disc that eventually became the solar system. In 2005 the mystery was solved (we think) at the University of Nice, France.  Neptune and Uranus, said the French astronomers, had actually formed in the inner solar system, and out of rock, like the Earth, Venus and Mars.
Four billion years ago the newly formed gas giants Jupiter and Saturn had turned the inner solar system into pool table on the break -  with the still molten planets and asteroids slamming and careening into and off of each other. This gravitational pin ball game had pulled the moon into a collision with the Earth, and allowed its capture. It had ground up the rocks trying to form a planet into the asteroid belt. And it had flung Uranus and Neptune out of their formation orbits and into their current orbits, leaving behind a lot of oddities as they swerved out into the edge of our solar system.
And that left Pluto. The more people looked at the guardian of the outer realms the odder it looked. Better telescopes, including one in earth orbit, showed it to have less than two tenths of 1% of the mass of the Earth, and to be only about half the size of our moon. That was too small to have perturbed the orbits of Neptune or Uranus. In fact it was even too small to be classified as a planet.
On August 24, 2006 the International Astronomical Union struck Pluto from the list of planets and gave it the new title of "134340 Pluto, dwarf planet".  It seems that for all of Percival Lowell's careful calculations, and for all of Clyde Tombaugh's perseverance, and for all the power of Alvan Clark's thumb,  finding Planet X right where it was supposed to be was...just a coincidence.  It was the human mind which mistook blind luck for a deep cosmological insight,  just as the swelling in the blood vessels behind Percival Lowell's eye had built the canals of Mars.
It makes me wonder how we can ever really be certain we are certain of anything. And it seems that no matter how big our telescopes become, we will always looking into a mirror.
- 30 -

Friday, May 04, 2018

HALL OF MIRRORS

I think it a profound insight that all telescopes involve mirrors. In 1846 this idea was stumbled upon by the obsessive-compulsive painter Alvan G. Clark, when he realized there was more money to be made in selling  telescopes to rich people than in just painting portraits of rich people. And since both involved selling positive self-images, Alvan dropped his brush and took up the polishing rag. It was said this self taught optician could feel imperfections in the glass lenses through his thumb while polishing them. For over a half a century Alvin and his sons ground magnificent telescopes for rich clients who saw funding observatories as grand monuments to their own intellectual beneficence. Five times Alvin Clark and Sons produced lenses for the largest refraction telescopes in the world. But it is another sad truth that making optical telescopes is an ephemeral art form, since all lenses tell lies. Even a Clark.
One of Alvan Clark's most enthusiastic customers was Mr. Percival Lowell, whose mommy gave him a 2 1/4 inch Clark on his fifteenth birthday. Astronomy was the kind of hobby mother and son could share atop their Brookline mansion. At his father's insistence Percival went into business in Japan (above - the tall one without the hat). But he always returned to his first love; astronomy. And as  the end of the 19th century approached, Percy was attracted by the approach of Mars. 
The more people looked at the red planet, the more it looked like earth. Kepler was the first to realize that Mars was a neighbor of ours. But it was the Dutchman Christiaan Huygens, who drew the first detailed maps of the planet's surface. Then in September of 1877, as the orbits of Earth and Mars converged, Giovanni Schiaparelli used a new telescope and saw what looked like mountain ranges and plains and long mysterious grooves which criss-crossed the planet. He described the grooves in Italian as “canalii”,  a word meaning a channel, or path.  It is sad to point out here, that although Percival Lowell spoke fluent Japanese, he did not speak Italian. 
In 1896, Percival retired from the business world and built his own world class observatory in the mountains, 7,180 feet above Flagstaff, Arizona, atop a peak he named Mars Hill.  Here, for $20,000 (half a million today) Percival installed a 24 inch Clark refracting telescope. Every summer night for the next 23 years, Percival Lowell (above) sat at the bottom of his telescope, observing Mars. During the days he slept in the 24 room mansion he also built on Mars Hill. Being born rich has its advantages, and Percival would have been a fool if he had not taken advantage of his advantages.
And what he saw through the eyepiece of his expensive magical tube was amazing. He saw canals - real canals - more than 180 of them, some of them 4,000 miles long. And he wondered what sort of creatures had constructed such a massive, intricate irrigation system. “Quite possibly, “ he wrote, “such Martian folk are possessed of inventions of which we have not dreamed...Certainly what we see hints at the existence of beings who are in advance of, not behind us, in the journey of life.” 
Percival wrote three books, “Mars”, “Mars and its Canals”, and “Mars as the Abode of :Life”. Each and every book became a best seller. He inspired H.G. Wells to write “War of the Worlds”, as well as inspiring Edgar Rice Burrows, who besides the “Tarzan” series, wrote 13 adventure books centering on Mars. By the year his third book was published, in 1907, Percival Lowell was recognized as the world's expert on the planet Mars. And then, almost over night, Percival's magical red world was deflated by his doppelganger, Mr. George Hale.
George Hale also came from a rich Boston family. But where Percival's father had insisted he attend business school, George's father had sent him to MIT to become a professional astronomer. And in 1908 George opened the lens cap on his new 60” reflector telescope in his new observatory atop California's 5,700 foot high Mount Wilson. And almost the first thing George peered at was Mars, where he found...no canals. Not a one. No matter how hard he looked. It is alleged that George saw an elf in his bedroom, but he saw no canals on Mars.
The photographic proof was conclusive. What Percival had seen as canals proved, when seen through a  newer, bigger, telescope,  proved to be just an optical illusion, or maybe the blood vessels in the back of Percival's own eye.  Percival had a nervous breakdown. And when he recovered he sought to re-establish his reputation. He took up the search for the the last great mystery in the night sky, the powerful conundrum of Planet X.
According to Percival's own mathematics, there was something very odd about the planets Neptune and Uranus. They were too big, their orbits were odd, Neptune was spinning on its side and they both wobbled. It looked to Percival as as if there had to be another planet further out from the sun, tugging at Uranus and Neptune. He called his suspect Planet X. Percival even calculated Planet X's mass, and he knew exactly where it had to be in the sky, 40 times further out from the sun than the earth.
For ten years Percival and his assistants – okay, mostly his assistants – scoured photographs of the night sky, searching for the tell-tale movement in the star field that would herald the discovery of Planet X. Twice the camera on Percival's 12” Clark took pictures of the moving X.  But the humans who had to examine each one of the thousands of photographs, failed to notice the one dot that had moved slightly. And then,  in 1916, at the age of sixty-one, Percival Lowell suffered a stroke and died. He was buried next to his beloved 12” Clark atop Mars Hill.  But thanks to Percival's fortune, the search for Planet X continued.
In 1930 Clyde Tombaugh found Planet X. And since he was being paid by Percival's endowment, and still using Percival's 12” Clark, Planet X was named using Percival Lowell's initials – PLuto. And isn't it amazing that Planet X became the official IX planet in the solar system? You don't often get to use Roman Numerals in a joke.
Ah, but things were about to get even more amazing. With the refinement of observations of the outer planets a number of new great mysteries appeared in the night sky, as they always do. The more you know the less you know, you know.  You know?
The first thing astronomers realized they did not know was why  two of those three cold blobs of rock and ice circling far out from the Sun– Neptune and Uranus - were so darn massive, too massive to have been formed so far out at the edge of the spinning disc that eventually became the solar system. In 2005 the mystery was solved (we think) at the University of Nice, France.  Neptune and Uranus, said the French astronomers, had actually formed in the inner solar system, and out of rock, like the Earth, Venus and Mars.
Four billion years ago the newly formed gas giants Jupiter and Saturn had turned the inner solar system into pool table on the break -  with the still molten planets and asteroids slamming and careening into and off of each other. This gravitational pin ball game had pulled the moon into a collision with the Earth, and allowed its capture. It had ground up the rocks trying to form a planet into the asteroid belt. And it had flung Uranus and Neptune out of their formation orbits and into their current orbits, leaving behind a lot of oddities as they swerved out into the edge of our solar system.
And that left Pluto. The more people looked at the guardian of the outer realms the odder it looked. Better telescopes, including one in earth orbit, showed it to have less than two tenths of 1% of the mass of the Earth, and to be only about half the size of our moon. That was too small to have perturbed the orbits of Neptune or Uranus. In fact it was even too small to be classified as a planet.
On August 24, 2006 the International Astronomical Union struck Pluto from the list of planets and gave it the new title of "134340 Pluto, dwarf planet".  It seems that for all of Percival Lowell's careful calculations, and for all of Clyde Tombaugh's perseverance, and for all the power of Alvan Clark's thumb,  finding Planet X right where it was supposed to be was...just a coincidence.  It was the human mind which mistook blind luck for a deep cosmological insight,  just as the swelling in the blood vessels behind Percival Lowell's eye had built the canals of Mars.
It makes me wonder how we can ever really be certain we are certain of anything. And it seems that no matter how big our telescopes become, we will always looking into a mirror.
- 30 -

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