SSLV-D1/EOS-02 Mission

SSLV-D1/EOS-02 Mission

  • ISRO launched its first Small Satellite Launch Vehicle (SSLV-D1) from Sriharikota. 
  • It launched Earth Observation Satellite-EOS-02 and a co-passenger student satellite ‘Azaadi SAT’ into low earth orbit (LEO).
  • However, after a successful lift-off at initial stage and separation of its three stages, the rocket placed satellites into 356 km x 76 km elliptical orbit instead of the designated 356 km circular orbit, making satellites no longer usable.

Small Satellite Launch Vehicle (SSLV)

  • ISRO developed SSLV is a rocket to launch  satellites weighing less than 500kg in Low Earth Orbit and 300 kg to Sun Synchronous Orbit (SSO).
  • It is a 3 stage Launch Vehicle configured with three Solid Propulsion Stages and liquid propulsion-based Velocity Trimming Module (VTM) as a terminal stage.
  • SSLV is configured with three solid stages 87 t, 7.7 t and 4.5 t.
  • SSLV is capable of launching Mini, Micro, or Nanosatellites (10 to 500 kg mass)
  • It is the smallest vehicle at 110-ton mass at ISRO.
  • It will take only 72 hours to integrate, unlike the 70 days taken now for a launch vehicle. Only six people will be required to do the job, instead of 60 people.
  • The other features include: it will reduce the cost of launch missions (is likely to cost a fourth of the current PSLV), shift the burden of commercial launch from PSLV, Launch on demand feasibility, etc.


NEO (Near Earth Orbit)

  • It lies at a height of about 400 km above the surface of earth.
  • It is the orbit closest to the earth, therefore the satellite orbiting in NEO has to overcome greater gravitational force of the earth.
  • Usually experimental satellites are launched in the NEO.

LEO (Low Earth Orbit)

  • It lies at a height of about 900 km above the surface of earth.
  • Here both experimental and operational satellites are launched. E.g. Remote Sensing Satellite etc.

GSO (Geostationary Orbit)

  • It lies at a height of 36,000 km above the equator of the earth.
  • It orbits around the earth with a period equal to earth’s average rotational period of 23 hours 56 min. 4.09 sec.
  • Communication satellites and broadcast satellites operate in this orbit.
  • Satellites like GSAT series etc.

 Sun-synchronous Orbit (SSO)

  • SSO is also called a heliosynchronous orbit .
  • SSO is a particular kind of polar orbit. Satellites in SSO, traveling over the polar regions, are synchronous with the Sun.
  • The SSO satellites rotate w.r.t earth from north to south.
  • Altitude range :- 200- 1000 km.
  • It is a nearly  polar orbit around a planet, in which the satellite passes over any given point of the planet’s surface at the same local mean solar time.
  • More technically, it is an orbit arranged so that it processes through one complete revolution each year, so it always maintains the same relationship with the Sun.

plutus ias current affairs eng med 10th August 2022