According to sources the Indian Space Research Organization (ISRO) in a statement said "AstroSat accomplished the difficult task of measuring X-ray polarization of Crab pulsar in the Taurus constellation during 18 months of its study for the first time”. Accordingly ISRO launched its first dedicated space observatory AstroSat on a Polar Satellite Launch Vehicle (rocket) on September 28, 2015, from its spaceport at Sriharikota in Andhra Pradesh.
Meanwhile the telescope measured the variations of polarization as the magnetized object (pulsar) spins 30 times per second. Moreover the ISRO's Ahmedabad-Physical Research Laboratory (PRL) Professor Santosh Vadawale in the paper said "The idea of using CZT Imager for X-ray polarization measurement has been around for a while, but this is the first time the idea was tested on ground before launch and then employed in space. This makes our measurements credible”.
Furthermore Professor Bhal Chandra Joshi and a team
from NCRA, Pune, monitored the radio pulsations from Crab with GMRT and Ooty
radio telescope, corrected anomalies and provided accurate ephemeris to the
imager and PRL provided the polarization detection
algorithm and ground calibration.