Aditya-L1 is an important launch, will take 125 days to reach: ISRO chief

Tirupati: As the countdown for India's maiden solar mission Aditya-L1 began on Friday, Indian Space Research Organisation (ISRO) chief S Somanath said that it is an important launch and the satellite will take 125 days to reach the L1 point.

Somanath offered prayers at Chengalamma Parameshwari Temple in Tirupati district, ahead of the launch of Aditya-L1 Mission, India's first solar mission, on September 2 at 11.50 am from the Sriharikota spaceport in Andhra Pradesh.

"Today the countdown of Aditya L1 is starting and it will launch tomorrow around 11.50 am. Aditya L1 satellite is for studying our Sun. It will take another 125 days to reach the L1 point. This is a very important launch. We have not yet decided (Chandrayaan-4), but we will announce it soon. After Aditya L1, our next launch is Gaganyaan, it will take place by the first week of October," Somanath said while talking to the reporters.

Aditya-L1 is India's first solar space observatory and will be launched by the PSLV-C57. It will carry seven different payloads to have a detailed study of the sun, four of which will observe the light from the sun and the other three will measure in-situ parameters of the plasma and magnetic fields.

The largest and technically most challenging payload on Aditya-L1 is the Visible Emission Line Coronagraph or VELC. VELC was integrated, tested, and calibrated at the Indian Institute of Astrophysics’ CREST (Centre for Research and Education in Science Technology) campus in Hosakote in collaboration with ISRO.

Aditya-L1 will be placed in a halo orbit around Lagrangian Point 1 (or L1), which is 1.5 million km away from the Earth in the direction of the sun. It is expected to cover the distance in four months' time.

This strategic location will enable Aditya-L1 to continuously observe the sun without being hindered by eclipses or occultation, allowing scientists to study solar activities and their impact on space weather in real time. Also, the spacecraft's data will help identify the sequence of processes that lead to solar eruptive events and contribute to a deeper understanding of space weather drivers.

Major objectives of India’s solar mission include the study of the physics of solar corona and its heating mechanism, the solar wind acceleration, coupling and dynamics of the solar atmosphere, solar wind distribution and temperature anisotropy, and origin of Coronal Mass Ejections (CME) and flares and near-earth space weather.

The atmosphere of the sun, the corona, is what we see during a total solar eclipse. A coronagraph like the VELC is an instrument that cuts out the light from the disk of the sun, and can thus image the much fainter corona at all times, the Bengaluru-based Indian Institute of Astrophysics said.