A fiery ball trailing streamers of light blazes against the night sky. A month ago?
A fiery ball trailing streamers of light blazes against the night sky. A month ago it wasn't there; In a month it will be gone. What does it mean?
To the ancients, comets were mysteries, fearsome intrusions into their well ordered heavens. Surely they foretold great events on Earth.
We no longer think comets accompany earthly disasters; But the mysteries of the comet - and the mysteries the comets may be a key to - are even more wonderful than the old tales.
When an especially bright comet appears - like the 1973-1974 appearance of Comet kohoutek - All Astronomy mobilizes to study it.
In March, 1973, Lubos Kohoutek a Czech Astronomer, noticed a faint fuzzy patch in a photograph he'd taken of the night sky. Two nights later on new photographs, the fuzzy patch was in a new position against the starry background. It Led moved, it was a new comet.
streaking toward the sun.
DR. ROEMER (SYNC)
Basically, you can think of a comet as a dirty iceberg or dirty snow-ball. A ball of icy gaseous material with solid particles frozen in. Now, we don't see that ball resolved even with the largest telescope. On Comet kohoutek, we think that ball, the nucleus is something like 25 miles in diameter.
And when the orbit computations came along to tell us that the comet was going to go unusually close to the sun, we realized that we were very likely going to have a good show on our hands.
As that iceberg goes close to the sun, as it warms up, if forms dust and gas in an envelope
around the nucleus, the Coma, and when that Coma is present, most of the light comes from it rather than, from the nucleus.
Sunlight continues to act on the material in the Coma
blowing it back to from a tail, often bent, but
the Solar Wind acts on
other kinds of particles in the Coma
As pushing much more strongly into a straight tail.
DR. ROEMER (SYNC) cont.
So we realize the comets are individuals We never know exactly what to expect, the nucleus may break up and you can get two little separated distinct comets. Sometimes there can be flares and brightness, increases of many times in the amount of light and once in a while, a comet disappears.
Billions of years ago, a vast cloud of gas and dust began to fall in on itself. As it became denser, its atoms became heated. When the dollapse was complete, the heat was intense enough for Atomic Fusion.
And the Sun Was born
Out of the remnants of the great cloud, the Planets formed.
But some part of that original cloud, gas and dust frozen far from the Sun remained in tact.
DR. KUIPER (SYNC)
Well, the theories of the formation of the Solar System have gone through quite a bit of evolution naturally, in the last 20 years or so since we have so very much more information now, thanks to the Space program, and the great developments in Astronomy.
But, these comets approach the Sun from different angles, different distances, that locations may be different, their compositions may be somewhat different, so that a bright comet is a tremendous source of information so we should get good information on the chemistry of the body.
DR. MARAN (SYNC)
Fortunately, the comet was discovered in March of 1973, we we've had 10 months to make our plans and get ready for it.
The important thing in the skylab beyond the Ultraviolet Instrumentation is that we are going to use a Cronagraph.
DR. MARAN (SYNC) Cont.
An instrument that blocks out the brightness of the Sun, so we can study the comet as it comes by the Sun.
The Astronauts can see any kind of unusual activity in the Tail or Head of the comet that might occur then, they can respond to it and make observations.
When we realize the comet will be coming by the Sun at the time when we would be launching our Mariner to Venus and Mercury,, we started planning to use the TV Cameras on the Mariner to photograph the comet the same time we photographed it from earth. By combining these pictures taken from the two different angles we can build up a sterossopic view the true shape of a comet.
A few times in every lifetime, A Stranger Comes Near The Sun.
And while it passes, trailing its glowing tail millions of miles across space
It's easy to see whey the Ancients thought it fearsome and great,
And why Astronomers regard each one as a unique opportunity
A key with which they may
unlock mysteries as old as the Universe and as eternal as time.