THE COMETS TALE: HISTORY/EXPLORATIONThroughout history, people have watched the bright objects called comets in the sky. At first, people knew very few facts about comets, so they made up stories and beliefs about them. Their ideas often made comets seem threatening and powerful. Gradually, people began to observe, record, and compare information on different comets. They began trying to explain comets using the tools and methods of science.See if you can see the changes in people's thinking as you look at these pictures made at different times in history. We'll ask what you think about some common comet questions, too.DATE: 1145 CEMany ancient people believed that the appearance of a comet was a sign of bad luck to come. Others saw them as signs of great events, or the rise and fall of a leader. They were not sure of the source or origin of comets. Do you know where comets come from? Even today scientists do not have all the answers to this question.DATE:1300 CE

This painting was done on a church wall in 1303-1306 by an artist named Giotto. A bright comet had recently been seen in 1301. The artist used a comet as a symbol of the historic moment because people in his time would still recall this exciting event. Scientists today know that the comet of 1301 was Comet Halley. A spacecraft was launched in 1986 to study Comet Halley. The spacecraft was named Giotto after this artist.People in this era were not sure about whether comets enter the earth's atmosphere or are further away like the planets or even the stars. What do you think about this? How big do you think comets are? Do you think they are like stars? More like planets? How might you try to answer these questions?

DATE: 1587 CE

London, The Warburg InstituteThese paintings from the year 1587 show two kinds of comets. By the 1500's, people had noticed that all comets do not look alike. They observed the sky, recorded what they saw, and tried to explain why there seemed to be different kinds of comets. They thought one type of comet would bring peace and abundance while another would bring sickness, wars, and the burning of houses. Comets don't normally enter the Earth's atmosphere. People discovered this with the use of telescopes invented in the 16th century (1500's). But is it possible that a comet could hit the earth? What would happen then? Do you think it has already happened? DATE: 1680

Do comets return to Earth or only pass by once? Well, one thing that will help answer this question is knowing if a comet circles around our Solar System, or just passes by in a straight path. The scientist Edmond Halley discovered that the comets of 1531, 1607, and 1682 were all the same comet (guess what it was named!) which was revolving around our Sun every 76 years.Once people realized comets behaved in a regular way like the planets, they seemed much less frightening.This 1680 painting of a beautiful comet with a long, golden tale, reflects a more positive interest people began to have about comets. This comet was so bright it could be seen in the daytime, not just at night

Be an astronomer: Can you find the year for the next time Comet Halley will appear? Remember, Comet Halley has a 76 year period. For example, if it was seen in 1531, the next time it would have been visible would have been: 1531 + 76 (years) = 1607 (keep adding 76 to figure out other years it was seen). So, if Comet Halley was viewed in 1986, when is the next time it will be seen? How old will you be when you see it?DATE: 1858

An artist named Mary Evans made this picture showing a comet seen over Paris, France in 1858. Notice the artist made two thin lines coming out of the comet.What do you think the lines might be? The word comet comes from the Greek name for "hairy star."Does this picture give you any ideas why the Greeks chose this name? It took people a while to figure out how to predict what path a comet would travel.In the 1700s and 1800s scientists learned to calculate the distances and speeds at which comets travel around the sun. At that time, there were no computers or calculators so everyone had to do the calculations by hand! Where in the solar system would you go to look for a comet?

DATE: 1900DATE: 1900As they invented more powerful telescopes and ways of photographing comets during the 1900's, people discovered much more about them. For instance, they discovered that comets lose material each time they pass the sun. With each trip around the sun, a comet becomes smaller and smaller, and may even disappear. Scientists predict that some comets have a life of about 76,000 years. These are the comets that travel quickly around the sun, like Comet Halley. Is traveling around the sun every 76 years fast for a comet? Yes! Some comets take a hundred thousand (100,000) years or more. If you just missed one of these comets and are waiting to see it, you will have to wait 100,000 years for it to come back. So, sit back and relax!DATE:2000 CE

What is the latest comet news? By now you may be wondering when you might get a chance to observe a comet yourself. Astronomers now track the locations of many comets, and tell the public when a comet may be visible, and where it will appear in the sky. New comets are also being discovered all the time with today's powerful telescopes and satellites.When this happens the scientists name the comet, predict its path, and how bright it may be.

Summer, 2000: Comet Linear and its amazing story!In the summer of 2000, a comet named Linear was discovered as it approached the earth and sun. For a short time it was visible at night with binoculars. Then Comet Linear violently broke apart around July 26, 2000, when it made its closest approach to the sun, leaving many smaller mini comets instead of one large comet.Comet Linear moving across the sky (repeating animation). www.astrophotographer.com

(credit:STScI-PR00-26 July 28, 2000 press release)At first Comet LINEAR had one large nucleus. Then, in a three day sequence of events the comet became twice as bright and a chunk of it blew off like a cork from a bottle.Later, the nucleus broke into many fragments. These smaller pieces of Linear continued traveling in the same direction, like bright trails of fireworks.

Though comets have been known to break apart before (in 1994 Comet Shoemaker-Levy 9 broke up before it struck Jupiter), this is the first time scientists have had a view of this from so close-up.

Fall 2000: A newly discovered comet!On October 7th, 1999, astronomers discovered that a new comet is coming and it was named Comet McNaught-Hartley (after the two people who discovered it). Scientists are studying this distant comet, and according to their predictions, Comet McNaught-Hartley is expected to be brightest in December 2000 or January, 2001.Beyond 2000:Will we see other comets in the future? Yes! Astronomers know that Comet Encke (EN-key), which has been studied for many years, will be flying by in the year 2003.This is its 59th known visit to the solar system. Comet Encke returns every 3.3 years, but it is not visible from Earth every time. In the year 2003 it will return and be visible.So, join the comet party and mark it on your calendar!Other new comets are being discovered every year.

This is the end of the History of Comets--Actually, it's really a history of what people know about comets! Click on "Continue" for more about what we know today.