Aditya-L1 : ISRO’s Mission to Study the Sun

Following the successful launch of the Chandrayaan-2 satellite to study the moon, ISRO now plans to launch a new satellite to study the sun. Dubbed the Aditya-L1, the satellite has been designed and will be built in mutual collaboration between the ISRO and other Indian research institutes like the Indian Institute of Astrophysics (IIA), Inter-University Centre for Astronomy & Astrophysics (IUCAA), Physical Research Laboratory (PRL), Space Physics Laboratory (SPL) and Laboratory for Electro-optic Systems (LEOS).

What is Aditya-L1?

• While Aditya refers to the sun, L1 refers to one of the five Lagrangian points between Earth and the Sun.
• When a satellite is placed at the Lagrangian point 1 (L1) of the Sun-Earth system, it can continuously view the Sun without any occultation/ eclipses.
• The Aditya L1 will be inserted in an orbit around the L1, which is 1.5 million km from the Earth.
• It will carry six additional payloads with enhanced science scope and objectives in addition to the Visible Emission Line Coronagraph (VELC).
• While it was slated to observe only the sun’s corona, it will now also provide observations of the un’s Photosphere (soft and hard X-ray) and Chromosphere (UV).
• The satellite payloads will also study the particle flux which emanates from the Sun and reaching the L1 orbit, and the magnetometer payload will measure the variation in magnetic field strength at the halo orbit around L1.

What happens now?

The project has already been approved and the satellite will be launched during 2019 2020 timeframe by PSLV-XL from Sriharikota.

What is the solar corona?

The outer layers of the Sun, which extend to thousands of km above the disc (photosphere) of the sun are referred to as the corona. It has a temperature of more than a million degree Kelvin which is much higher than the solar disc temperature of around 6000K.