Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2001 January 8
See Explanation.  Clicking on the picture will download 
 the highest resolution version available.

Help NASA Classify Martian Craters
Credit: Sonie Lau, NASA Ames

Explanation: The large Martian crater above just left of center: is this a fresh crater, a degraded crater, or a ghost crater? Complex image recognition tasks like these are currently done more reliably by a human than a computer. Additionally, there are so many craters on Mars that NASA just doesn't have enough people to classify them all! Therefore, you can help humanity's understanding of the surface of Mars by volunteering to classify craters. All you need for this pilot study is a proper web browser and a mouse. If asked to classify the above crater, you might best respond that it appears relatively fresh, as it exhibits a sharp rim and a well-preserved interior. Degraded craters are typically older and have their rims more rounded, while "ghost craters" are the oldest of all and only faintly discernable.

Tomorrow's picture: Calling All Stars

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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
NASA Technical Rep.: Jay Norris. Specific rights apply.
A service of: LHEA at NASA/GSFC
& Michigan Tech. U.