03, Apr 2019
Prelims level : Space technology Mains level : Paper IV Technology
Why in News:
- NASA criticised India for the test, describing that it had endangered International Space Station.
- There are a large number of satellites currently in space, many of which have outlived their utility and orbiting aimlessly.
- The missile was launched from the Dr A P J Abdul Kalam island, struck a predetermined target which was a redundant Indian satellite that was orbiting at a distance of 300 km from the Earth’s surface.
- The National Aeronautics and Space Administration is an independent agency of the United States Federal Government responsible for the civilian space program, as well as aeronautics and aerospace research. It was established in 1958.
- Most US space exploration efforts have been led by NASA, including the Apollo space missions, the Space shuttle, etc.
International space station:
- The International Space Station (ISS) is a space station, or a habitable artificial satellite, in low earth orbit from 320 km (199 mi) to 400 km (249 mi) above the Earth’s surface.
- Its first component was launched into orbit in 1998, with the first long-term residents arriving in November 2000 and has been inhabited continuously since that date. The ISS is the largest human-made body in low Earth orbit and can often be seen with the naked eye from Earth. The ISS programme is a joint project between five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA (Japan), ESA (Europe) and CSA(Canada). The ISS serves as a microgravity and space environment research laboratory in which crew members conduct experiments in biology, human physiology, physics, astronomy and other fields.
Apogee and perigee:
- Apogee and perigee refer to the distance from the Earth to the moon. Apogee is the farthest point from the earth. Perigee is the closest point to the earth and it is in this stage that the moon appears larger.
Low earth orbit:
- The low earth orbit extends from 160km above Earth and ends at 2000km. More than 800 satellites are currently in orbit in the Low-Earth region. The most popular of these is the International Space Station and the Iridium network of communication satellites.
Problem of space debris:
- Anything launched into the space remains in space, unless it is specifically brought down or slowly disintegrates over decades or centuries.
- A satellite that is destroyed by a missile disintegrates into small pieces, and adds to the space debris. Satellites that are past their life and are no longer required also remain in space, orbiting aimlessly in some orbit. These included active and inactive satellites, rockets and their parts, and other small fragments. According to the NASA, there were 19,137 man-made objects in space that were large enough to be tracked. The threat from the space debris is that it could collide with the operational satellites and render them dysfunctional.