When the launch site is more near the equator, less energy (or a smaller launch vehicle) is required to put a satellite in GTO (Geo-Synchronous Transfer Orbit). So a GSLV from SHAR need not be as massive (hence as complex) as say Soyuz or Proton launch from Baikanour. So, why the hell is the GSLV doing a 'submarine' ?
Just to show what I mean, read on the report from NYT about the difference in orbits of HST (Hubble Space Telescope) & ISS (International Space Station) and what it augurs for the shuttle mission to repair HST in 2008.
----------------Excerpt from NYTimes, Nov 5, 2006 -----------
Every space shuttle flight has its risks, but the one to repair and upgrade the HST in 2008 is riskier than usual. If the shuttle runs into trouble, it won’t be able to rendezvous with the International Space Station for help. The best it could do is collide with it.
The United States and Russia set the orbits of the HST & ISS at different angles to the Equator.
Decades ago, the United States built its main launching pads at Cape Canaveral, Fla., almost as far south as possible, to make it easier for its space vehicles to achieve orbit.
Like a rock thrown from a speeding car, a spacecraft launched from a low latitude gets a push from the earth’s rotation — 1,000 miles an hour at the Equator, tapering to zero at the poles.
The HST was launched there in 1990 (on Shuttle 'Discovery') at an angle of 28.5 degrees from the Equator, the lowest angle easily achievable from Cape Canaveral. The minimum angle of orbit equals the latitude of the launch point, and Cape Canaveral is at 28.5 degrees north.
The ISS was built to orbit at an angle of 51.6 degrees from the equator. The orbit was chosen so that the Russia could launch components and crews from Baikonur, Kazakhstan, at latitude 45.9 degrees north, to build and service the Space Station.
For the 2008 mission the shuttle would have to be launched at an angle of 28.5 degrees to match the Hubble’s orbit. It is possible for the shuttle to change its altitude to match the altitude of the space station. But a successful rendezvous would require the relative motion of the two spacecraft to be zero. And because the angles of their orbits are different, the two craft would cross paths at several miles per second.
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Just to show what I mean, read on the report from NYT about the difference in orbits of HST (Hubble Space Telescope) & ISS (International Space Station) and what it augurs for the shuttle mission to repair HST in 2008.
----------------Excerpt from NYTimes, Nov 5, 2006 -----------
Every space shuttle flight has its risks, but the one to repair and upgrade the HST in 2008 is riskier than usual. If the shuttle runs into trouble, it won’t be able to rendezvous with the International Space Station for help. The best it could do is collide with it.
The United States and Russia set the orbits of the HST & ISS at different angles to the Equator.
Decades ago, the United States built its main launching pads at Cape Canaveral, Fla., almost as far south as possible, to make it easier for its space vehicles to achieve orbit.
Like a rock thrown from a speeding car, a spacecraft launched from a low latitude gets a push from the earth’s rotation — 1,000 miles an hour at the Equator, tapering to zero at the poles.
The HST was launched there in 1990 (on Shuttle 'Discovery') at an angle of 28.5 degrees from the Equator, the lowest angle easily achievable from Cape Canaveral. The minimum angle of orbit equals the latitude of the launch point, and Cape Canaveral is at 28.5 degrees north.
The ISS was built to orbit at an angle of 51.6 degrees from the equator. The orbit was chosen so that the Russia could launch components and crews from Baikonur, Kazakhstan, at latitude 45.9 degrees north, to build and service the Space Station.
For the 2008 mission the shuttle would have to be launched at an angle of 28.5 degrees to match the Hubble’s orbit. It is possible for the shuttle to change its altitude to match the altitude of the space station. But a successful rendezvous would require the relative motion of the two spacecraft to be zero. And because the angles of their orbits are different, the two craft would cross paths at several miles per second.
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