The T-22.5 hour Countdown for Monday's launch of PSLV-C62 / EOS-N1 Mission Earth Observation Satellite along with 15 other co-passenger satellites began at the spaceport of Sriharikota on Sunday.

The PSLV-C62 mission will lift-off on Monday morning at 1018 hrs, from the First Launch Pad at Satish Dhawan Space Centre, Sriharikota.

This would be the first launch for ISRO this New Year. EOS-N1, also called Anvesha, is an Indian hyperspectral earth imaging satellite built by DRDO for strategic defence purposes as well as for civilian monitoring in agriculture, urban mapping, and environmental assessment.

ISRO said after the Launch Authorisation Board (LAB) gave the clearance and the Mission Readiness Review too gave the nod for the launch, the 22.5 hour countdown began at 1248 hrs on Sunday during which propellant filling operations would be carried out in the four-stage vehicle.

ISRO source said the 22.5 hrs countdown for PSLV-C62 mission- the 64th flight of PSLV and the 5th mission of the PSLV-DL variant., began at 12 48 hrs and was progressing smoothly.

The 44.4 metre tall PSLV with a lift off mass of 260 tonnes, is a four stage vehicle powered by solid and liquid propellants and is the versatile, most relaible and workhorse launch vehicle of ISRO.

The EOS-N1 and 14 co-passenger satellites will be injected into a Sun Synchronous Orbit at an altitude of 505 km with an inclination of 97.5 degrees and the KID Capsule into a re-entry trajectory.

After injection of EOS-N1 and 14 satellites, the PS4 stage will be re-started to de-boost and enter a re-entry trajectory, followed by

KID Capsule separation. Both PS4 stage and KID capsule will re-enter into Earth's Atmosphere and impact will be in the South Pacific Ocean.

The PSLV-C62 mission is one of longest to be flown by ISRO. About 16 minutes into the rocket's flight, its fourth stage engine will be cut off and would coast for about a minute. And about 17 minutes post lift off, the Indian satellite Avnesha/EOS-N1 and 14 other co-passengers will be ejected.

One of the interesting satellites to be ejected will be AyulSat – sort of a space fuel tanker for spacecraft developed by Indian company OrbitAid. The satellite is a technology demonstration one for in-orbit fueling. The in-orbit fueling will extend the life of an orbiting satellite and thereby reduce the overall cost and the space debris.

ISRO said this is the 9th dedicated commercial mission undertaken by NewSpace India Limited (NSIL) to build and launch the EOS-N1 earth observation satellite for a user along with providing launch services for 14 co-passenger satellites from domestic and international customers.

The PSLV-C62 mission will also demonstrate KID or Kestrel Initial Technology Demonstrator from a Spanish startup, which is a small-scale prototype of a re-entry vehicle being developed by the startup. The KID will be the last co-passenger to be injected, after which it is slated to re-enter the earth's atmosphere towards splashdown in the South Pacific Ocean.