ISRO’s maiden Solar mission Aditya-L1 planned for June-July ’23

Chennai: With the Indian Space Research Organisation (ISRO) planning its first Sun mission in the June-July window, that will end in August, the Indian Institute of Astrophysics (IIA), Bengaluru handed over the Visible Line Emission Coronagraph (VELC) payload for Aditya-L1 mission to ISRO.
It was handed over at a ceremony held yesterday at the Centre for Research and Education in Science and Technology (CREST) Campus, Hosakote, near Bengaluru.
VELC payload was designed and realised at CREST campus.
The payload was handed over to Director, U R Rao Satellite Centre (USRC) by Director, IIA in the presence of Chairman, ISRO/Secretary, Department of Space S Somanth in the presence of Project Aditya-L1 Mission Director Ms NigarShaji and VEKC Principal Investigator Dr. B Raghavendra Prasad.
The payload would be integrated to the satellite at URSC. VELC has a mechanism to occult the solar disc to separate and discards
the light from the disk.The light from the Corona is captured by the coronagraph for further processing. VELC aims to collect the data for
solving how the temperature of the corona can reach about a million degrees while the Sun’s surface itself stays just over 6,000 Deg C.
For this, the payload targets at the continuous observations of the Corona, right from its lowermost boundary upwards after having
discarded the bright light from the solar disc.
VELC weighs 90 kg and is 1.7 m x 1.1 m x 0.7 m in dimension, ISRO said on Friday.
The spacecraft will be placed in a halo orbit around the first Lagrange point, L1, of the Sun-Earth system. A satellite around the L1 point has the major advantage of continuously viewing the Sun without occultation/eclipses.
This position provides a greater advantage of observing solar activitie continuously.
Aditya-L1 carries seven payloads to observe the photosphere, chromosphere, and the outermost layers of the Sun (the corona) using electromagnetic and particle detectors. Four payloads directly view the Sun from the unique vantage point of L1, and the remaining three payloads carry out in-situ studies of particles and fields at the Lagrange point L1..
ISRO is planning to launch the Aditya-L1 mission by June or July this year. Aditya-L1 is the first Indian space mission to observe the Sun and the solar corona.
ISRO Chairman S. Somanath, speaking at the handover ceremony of the VELC payload said the Aditya-L1 mission will be launched by June or July as the launch window for the mission would close by August.
Following the handover of the VELC payload, the ISRO will now conduct further testing of VELC and its eventual integration with the Aditya-L1 spacecraft.
“This is the main instrument (VELC payload) on board the Aditya-L1 satellite. There are also other instruments which are developed by the ISRO and other institutions. Currently, we are getting ready with the satellite. The payload will be taken to the U.R. Rao Satellite Centre in Bengaluru, where we will integrate it with the Aditya-L1 satellite which will undergo a lot of testing, evaluation and finally, it will be launched using the PSLV,” Somanath added.
Raghavendra Prasad, Principal Investigator, VELC payload, said that the payload will be able to observe the corona continuously and the data provided by it is expected to answer many outstanding problems in the field of solar astronomy.
“No other solar coronagraph in space has the ability to image the solar corona as close to the solar disk as VELC can. It can image it as close as 1.05 times the solar radius. It can also do imaging, spectroscopy, and polarimetry at the same time, and can take  observations at a very high resolution (level of detail) and many times a second,” Prof. Prasad said. (UNI)