Q. ASTROSAT:

1. is India’s first multi–wavelength astronomical satellite
2. has been developed by ISRO
3. aims at understanding the high energy stars and black holes

Which of the above statements is/are correct?
Answer: 1, 2 & 3
Notes: ASTROSAT is India's first dedicated multi-wavelength space observatory. It was launched on September 28, 2015 from the Satish Dhawan Space Centre in Sriharikota. The satellite is in a 650-km, near-equatorial orbit. ASTROSAT's mission is to study celestial sources in X-ray, optical, and UV spectral bands simultaneously. It carries five scientific instruments that can observe the Universe in different wavelengths of light. The instruments cover the following regions of the electromagnetic spectrum:

• Visible (320–530 nm)
• Near UV (180–300 nm)
• Far UV (130–180 nm)
• Soft X-ray (0.3–8 keV and 2–10 keV)
• Hard X-ray (3–80 keV and 10–150 keV)

ASTROSAT's field of view is a circle of ~ 28 arcmin diameter. The angular resolution is 1.8 arcsec for the ultraviolet channels and 2.0 arcsec for the VIS channel. The satellite's lift-off mass was 1515 kg. It was launched by the Indian launch vehicle PSLV-C30 (XL) rocket. The expected operating life time of the satellite is more than five years.