Country’s first solar mission likely to be launched by June-July.

• The Indian Institute of Astrophysics, Bengaluru handed over the primary payload of the country’s first mission to sun to the Indian Space Research Organisation (ISRO) for integration with the other payloads on board the satellite.
• The payload handed over on Thursday called ‘Visible Emission Line Coronograph’ (VELC) will be the main payload among seven designed to study various aspects of the sun like its atmosphere, solar wind acceleration and the origin of coronal mass ejection.
• The VELC, which was conceptualised and designed in 15 years, may help is solving one of the main puzzles of solar astrophysics — why the sun’s atmosphere called corona is a million degrees hot even though the surface is just over 5,700 degrees Celsius?
• The VELC can image the solar corona down to 1.05 times the solar radius, which is the closest any such payload has imaged. It can also take these observations roughly 3 times every second, and with a high resolution of 2.5 arc seconds per pixel.

About Aditya  L1

• Aditya-L1 is India’s first space-based mission to study the Sun. The satellite will be carried by the rocket Polar Satellite Launch Vehicle (PSLV).
• To get an unobstructed, continuous view of the sun, the satellite will travel to the L1 or Lagrange point between the sun and the earth.
  • Lagrange points — there are five between any two celestial objects — are referred to as parking spots in space because the gravitational pull of the celestial objects equals the force required to keep it in orbit. So, a satellite can stay in Lagrange points between any two celestial objects without expending fuel.
• The Aditya-L1 will carry as many as seven payloads – VELC (visible emission line coronagraph), SUIT (solar ultraviolet imaging telescope), SoLEXS (solar low energy X-ray spectrometer), HEL1OS (high energy L1 orbiting X-ray spectrometer), ASPEX (Aditya solar wind particle experiment), PAPA (plasma analyser package for Aditya), and advanced tri-axial high-resolution digital magnetometers.v