Developed Aditya-L1 payload for solar corona study: Indian Institute of Astrophysics

One of the seven payloads of Aditya-L1, India’s first scientific mission to study the sun, has been designed, assembled, and tested by the Indian Institute of Astrophysics (IIA).

The institute based in Bengaluru said on Tuesday (August 29) that it developed the Visible Emission Line Coronagraph (VELC) in close collaboration with the ISRO. Aditya-L1 is set to be launched from Sriharikota in Andhra Pradesh on September 2.

“IIA had to build India’s first large-sized ‘Class to Clean Rooms’ at (sic) its CREST campus in Hosakote to assemble VELC,” the IIA said in a statement.

Aditya L-1’s payloads

Aditya L-1 will carry six other payloads — Solar Ultraviolet Imaging Telescope (SUIT), Aditya Solar Wind Particle Experiment (ASPEX), Plasma Analyser Package for Aditya (PAPA), SoLEXS-Solar Low Energy X-ray Spectrometer (SoLEXS), High Energy L1 Orbiting X-ray Spectrometer HEL1OS, and Magnetometer with enhanced science scope and objectives possible by extensive remote and in-situ observation of the Sun.

“Earlier, this mission was conceived as Aditya-1, with a 400-kg-class satellite carrying one payload, the Visible Emission Line Coronagraph (VELC), and was planned to be launched in an 800-km low Earth orbit,” the IIA said.

A satellite placed in the halo orbit around the first Lagrangian point (L1) of the Sun-Earth system has the major advantage of continuously viewing the Sun without any occultation/eclipses, the IIA explained.

Therefore, the Aditya-1 mission has now been revised to “Aditya-L1 mission” and will be inserted in a halo orbit around the L1, which is 1.5 million km from the earth towards the Sun, it explained.

About VELC payload

“The VELC payload on-board Aditya-L1 is an internally occulted solar coronagraph with simultaneous imaging, spectroscopy and spectro-polarimetry channels close to the solar limb. VELC is designed to image solar corona,” IIA said.

Both imaging and spectroscopic observations obtained by the VELC payload are key for studying the diagnostic parameters of solar corona and dynamics, as well as the origin of the coronal mass ejections and magnetic field measurements of the solar corona.

Stokes vector measurements in the plane-of-sky and imaging in white-light are the unique features of this payload, it added.

The scientific studies by the satellite will enhance the current understanding of the solar corona and also provide vital data for space weather studies, the IIA said.

India scripted history when the Vikram lander of Chandrayaan-3 made a soft-landing on the surface of the Moon on August 23.