On February 14 at 00:29 UTC, an Indian PSLV rocket launched the EOS-4 radar satellite into a sun-synchronous orbit from the First Launch Pad at the Satish Dhawan Space Center in southern India. This was the 54th PSLV launch since the first one in 1993.

Seventeen minutes after launch, the fourth stage of the launch vehicle separated EOS-4 and the two other smallsats into orbit. EOS-4, also known as RISAT-1A, is a C-band synthetic aperture radar satellite. Like similar satellites, it will be used for agriculture, flood mapping, and forestry. It will complement other remote sensing satellites operated by India, such as Cartosat and Resourcesat.

Another satellite on PSLV C52 was INS-2TD. It is a type of remote sensing satellite, this time with a thermal camera. This sensor is useful for surface temperatures and differentiating between types of vegetation such as crops and forests. INS-2TD is a technology demonstrator trying this sensor out for the future INS-2B satellite.

Finally, INSPIREsat-1 is a student satellite built as a collaboration between four universities in India, the USA, Singapore, and Taiwan. It will investigate the atmosphere of both the Earth and the Sun. Its payload is funded by NASA and is called the Miniature X-Ray Solar Spectrometer 3 or MinXSS-3. This experiment will investigate the soft X-rays released during solar flares, specifically how they interact with the Earth’s ionosphere. 

The soft X-rays from solar flares can interfere with radio wavelength signals traveling through the ionosphere. Before this experiment, which has flown on two previous CubeSats, soft X-rays had not been studied. The experiment will also help scientists explain how the Sun’s outer atmosphere, the corona, is heated.

More Information

PSLV-C52/EOS-04 Brochure (ISRO)

NASA press release

Launch video