With the successful launch of XPoSAT  or the X-ray Polarimeter Satellite, at 9.10 am , India will become the second country after the US to have an 'observatory' to study black holes. The new mission comes on the heels of India's successful moon mission Chandrayaan.

Using X-ray photons and their polarisation, XPoSAT will help study the radiation from near black holes and neutron stars. It carries two payloads namely POLIX (Polarimeter Instrument in X-rays) and XSPECT (X-ray Spectroscopy and Timing).

The satellite will measure polarisation of X-rays in the energy band 8-30keV emanating from about 50 potential cosmic sources through Thomson Scattering by POLIX payload.

It will carry out long term spectral and temporal studies of cosmic X-ray sources. It will also carry out polarisation and spectroscopic measurements of X-ray emissions from cosmic sources through POLIX and XSPECT payloads..

When stars run out of fuel and 'die', they collapse under their own gravity and leave behind black holes or neutron stars.

Black holes have the highest gravitational force in the universe and neutron stars have the highest densities.

Gathering more information on this, the mission will help unravel the mysteries of the ultra-extreme environments in space.

The XPoSat satellite cost around Rs 250 crore (approximately $30 million) while the NASA IXPE – which is on a similar mission since 2021 -- required an outlay of $188 million.

The Indian satellite is expected to last more than five years compared to the two-year life span of the NASA IXPE,

The XPoSAT mission will see the Polar Satellite Launch Vehicle or PSLV -- undertake its 60th flight. Besides the 469-kg XPoSAT, the 260-tonne PSLV will lift off with 10 experiments.