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.

2002 December 17
See Explanation.  Clicking on the picture will download
 the highest resolution version available.

Beefing Up the International Space Station
Credit: STS-113 Shuttle Crew, NASA

Explanation: The International Space Station (ISS) will be the largest human-made object ever to orbit the Earth. The station is so large that it could not be launched all at once -- it is being built piecemeal with large sections added continually by flights of the Space Shuttle. To function, the ISS needs trusses to keep it rigid and to route electricity and liquid coolants. These trusses are huge, extending over 15 meters long, and with masses over 10,000 kilograms. Pictured above at the end of last month, astronaut Michael Lopez-Alegria works to install the Port-One Truss. On the right is the end of Canadarm2, the robotic remote control arm of the ISS.

Tomorrow's picture: Io Volcano

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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
& NASA SEU Edu. Forum
& Michigan Tech. U.