Aditya-L1 mission to study the Sun to be launched on September 2, announces ISRO

The mission, to be launched at 11.50 am on September 2, would carry seven payloads to observe the photosphere, chromosphere and the outermost layers of the Sun, the corona, in different wavebands.

India’s first space-based mission to study the Sun is ready for a September 2 launch, the Indian Space Research Organisation (ISRO) announced on Monday. The PSLV-C57/Aditya-L1 mission will take off from the Satish Dhawan Space Centre in Sriharikota at 11.50 am on Saturday.

With the Aditya-L1 mission, ISRO plans to place the spacecraft on a halo orbit around L1, the first Lagrange point of the sun-earth system, at about 1.5 million km from the earth. Spacecraft stay in position on Lagrange points where gravitational forces from the two large bodies cancel each other out, making the smaller body – the spacecraft – move along with them. This positioning will give the spacecraft the advantage of uninterrupted viewing of the Sun, without blockage, and with reduced consumption of fuel.

Observing the Sun from space is important because earth-based instruments cannot detect various radiations emitted from the sun, making studies based on these radiations impossible.

The mission will carry seven payloads that will observe the Sun’s photosphere (its visible surface), corona (its outermost layer), and chromosphere (the atmospheric layer in between). Stated among the mission objectives are a study of the dynamics of the Sun’s upper atmosphere (chromosphere and corona), patterns in coronal heating, space weather, magnetic field measurements in the corona, and plasma and magnetic field eruptions from the corona known as Coronal Mass Ejections (CMEs).

Visible Emission Line Coronagraph (VELC) is the mission’s key payload, developed by the Indian Institute of Astrophysics, Bengaluru. It will be one of the four remote-sensing payloads on board the spacecraft. VELC will study CMEs and their impact on space weather, and try to understand factors that make the corona significantly hotter than the Sun’s surface.

The other payloads include Solar Ultra-violet Imaging Telescope (SUIT), Aditya Solar wind Particle EXperiment (ASPEX), Plasma Analyser Package for Aditya (PAPA), Solar Low-Energy X-Ray Spectrometer (SoLEXS) and High Energy L1 Orbiting x-ray Spectrometer (HEL1OS). With the Magnetometer on board, ISRO aims to measure the interplanetary magnetic fields at L1.

The space agency has invited the public to witness the launch from the Launch View Gallery at Sriharikota by registering using this link.