• PSLV mission carrying EMISAT — the country’s first satellite for gathering electronic intelligence (ELINT) to locate hostile radars for the military — will also be the longest flight for the Indian polar launch vehicle.
  • The mission is numbered C-45 and carries 28 small, foreign customer satellites from four countries. The satellites together weigh 220 kg.
  • The EMISAT payload is from the DRDO.
  • The 436-kg EMISAT will be released 17 minutes into launch in its designated orbit 749 km away from earth.
  • The 28 small foreign customer satellites will be released almost an hour later at a lower orbit of 504 km.
  • All of them will be out within five minutes, according to pre-launch information put out by the Indian Space Research Organisation (ISRO.)
  • Later PS4 will be fired thrice and eventually put into an orbit at 485 km.
  • This is the third consecutive PSLV mission in which ISRO will re-use its fourth stage as a space testbed.
  • Earlier, the stages wasted away as floating debris once they released the satellites.
  • We are doing a three-orbit mission for the first time.
  • We earlier did two-orbit launches.
  • Such a multi-orbit capability is beneficial when there are different launch customers who need to put their satellites in different orbits.
  • With this capability, we need to use just one launcher for different customers.
  • In this mission, PS4 will carry three minor payloads or experiments.
  • ISRO said it had equipped the stage with power-generating solar panels for the first time.
  • Among the tiny commercial co-passenger satellites, 20 are from a previous U.S. customer, Planet.
  • The 20 Flock 4a Dove satellites are part of Planet’s earth observation network.
  • Since 2016, the company has used the PSLV four times to put more than 100 of its small “cubesats” in space.
  • In February 2017, when the PSLV-C37 rocket lifted up a record 104 small satellites to space, 88 of them belonged to Planet.
  • Four small LEMUR satellites from another U.S. customer are for monitoring maritime traffic or automatic identification system.
  • One satellite each from Spain, Switzerland and Lithuania are also part of the payload.