Credit: Mars in History

Percival Lowell's Martian Canals. Mars has fascinated humanity for centuries, especially when it was viewed through a telescope for the first time. Many observers noted linear features connecting dark spots on the face of Mars. These were interpreted by some observers, most notably Percival Lowell, as canals built by a great, dying Martian civilization to carry water from the poles to bring water to their crops. Later, photographs proved that the "canals" were simply an optical illusion.

The History of Astronomy

(Links | Questions)

Astronomy has been practiced for as long as humans have been looking at the sky and wondering what it all means. Early civilizations, for example, Harappans, Mayans, and ancient Chinese used astronomy to keep track of time, orient their cities, and to try to predict the future. Early astronomy was a mix of careful observation of the positions and motions of the heavenly bodies, religion, and astrology.

The Greeks named the stars and plotted their positions. While Europe muddled through the Dark Ages, astronomers in the Middle East translated Greek texts into Arabic, preserving and expanding humanity's knowledge of the sky.

The real renaissance of astronomy began with Nicholaus Copernicus, who advanced the idea that the Sun is in the center of the Solar System. Armed with the excellent naked-eye observations of Tycho Brahe, Johannes Kepler formulated his Three Laws of Planetary Motion, which, for the first time, correctly described the way the planets move through the Solar System. Galileo Galilei was the first person to use a telescope to look at celestial bodies (though he did not invent the telescope) and discovered the four brightest moons of Jupiter, proving that there are things in the Solar System that don't revolve around the Sun.

Since Galileo's time, astronomy has made great strides, but, surprisingly, as late as the 1920's, astronomers were still debating about whether other galaxies were simply nearby nebulae, or if they were faraway "island universes," made up of billions of stars. The first planets outside our Solar System were not discovered until 1991, and we did not find any planets around normal stars until 1995.

Who knows what discoveries the future will bring!

The Ask an Astronomer team's favorite links about The History of Astronomy:

History of Astronomy links. Many links to lots of different topics in the history of astronomy, from ancient astronomy to the history of aeronautics. Also general history links.
The MacTutor History of Mathematics Archive: Biographies of mathematicians, astronomers, physicists, etc.
The History of Women in Astronomy: Biographies of famous women astronomers.

Previously asked questions about The History of Astronomy:

(General questions | Archaeoastronomy)

General questions:

Where can I see Newton's original reflecting telescope? (Beginner)
Why is it called astronomy when all the other sciences end in -ology? (Beginner)
What are the names of the earth, moon, sun, and solar system? (Beginner)
How does astronomy benefit humankind? (Beginner)
Who discovered each planet? (Intermediate)
Is the Moon moving away from the Earth? When was this discovered? (Intermediate)
Why was the Platonic year named after Plato? (Intermediate)
Why are most months 30 or 31 days long? (Intermediate)
Is there a proof that Earth moves? (Intermediate)
Who (and when) discovered that the earth's axis is on a 23 degree tilt? (Intermediate)
Who first measured the speed of light? (Intermediate)
What are constellations used for? (Intermediate)
What are the largest radio wavelengths observed from radio sources in the sky? (Intermediate)
Why have star signs shifted by one constellation? (Intermediate)
What is the origin of the stellar classification system "OBAFGKM"? (Intermediate)
How long has humanity known that we live in a galaxy similar to others in the Universe? (Intermediate)
When are there 5 Sundays in February? (Intermediate)
When did people discover that the Sun is a star? (Intermediate)
Why do people draw stars with five points? (Intermediate)
What happened to the girl who named Pluto? (Intermediate)
How was the starting point for the Julian Date system chosen? (Advanced)

Archaeoastronomy:

Was Stonehenge built to mark solar phenomena? (Intermediate)
What are the facts about the Star of Bethlehem? (Intermediate)
How different would the night sky have looked in 40,000 B.C.? (Intermediate)
Did the Sumerians measure precession? (Intermediate)
Why is a day divided into 24 hours? (Intermediate)
What's going to happen on December 21st 2012? (Intermediate)
When can I see the Moon through the hole in the Pantheon? (Intermediate)
What month was it when Odysseus saw Orion in 1000BC? (Advanced)

How to ask a question:

If you have a question about The History of Astronomy which isn't answered above, submit it here. If you have a question about another area of astronomy, find the topic you're interested in from the archive on our site menu, or go here for help.

URL: http://curious.astro.cornell.edu/history.php
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Last modified: September 7, 2007 9:33:26 AM

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