Aditya-L1 solar mission launch today: Highlights | India News

NEW DELHI: The countdown for the launch of India’s maiden solar mission, Aditya L1 onboard the PSLV, commenced from Sriharikota on Friday.
India’s solar mission comes close on the heels of its successful lunar endeavour — Chandrayaan-3. With Aditya-L1, Isro will venture into the study of solar activities and its effect on space weather.
Aditya L1 is designed for providing remote observations of the solar corona and conduct in-situ observations of the solar wind at L1 (Sun-Earth Lagrangian point), which is about 1.5 million kilometres from the Earth.
Here are some key highlights of the solar mission:
Objective of the mission
The scientific objectives of Aditya-L1 include the study of coronal heating, solar wind acceleration, coronal mass ejections (CMEs), dynamics of solar atmosphere and temperature anisotropy.
According to ISRO, there are five Lagrangian points between the Sun and the Earth, and the L1 point in the Halo orbit would provide a greater advantage of continuously viewing the Sun without any occurrence of eclipse.
On embarking on such a complex mission, ISRO said the Sun is the nearest star and therefore can be studied in much more detail as compared to the others.
By studying the Sun much more about could be learnt about stars in the Milky Way as well as in various other galaxies, ISRO said.

What is Aditya-L1
Aditya-L1 is a satellite dedicated to the comprehensive study of the Sun. It has seven distinct payloads — five by Isro and two by academic institutions in collaboration with Isro — developed indigenously.
Following its scheduled launch, Aditya-L1 will stay in Earth-bound orbits for 16 days, during which it will undergo five manoeuvres to gain the necessary velocity for its journey.
To achieve this, the spacecraft is packed with seven scientific instruments: The two main payloads are Visible Emission Line Coronagraph (VELC) for Corona imaging & spectroscopy studies and Solar Ultraviolet Imaging Telescope (SUIT) for Photosphere and Chromosphere imaging (narrow & broadband).
Launch timing
The Sun observatory mission will be fired from the second launch pad at this spaceport at 11.50 am on Saturday. ISRO Chairman S Somanath said the Sun mission will take 125 days to reach the exact radius.
The spacecraft’s trajectory
Initially, the Aditya-L1 spacecraft would be placed in a low earth orbit. It would be made more elliptical and later the spacecraft will be launched towards the Lagrange point L1 by using on-board propulsion systems.
As the spacecraft travels towards L1, it will exit the Earth’s gravitational Sphere of Influence. After exit, the cruise phase will start and subsequently, the spacecraft will be injected into a large halo orbit around L1. It would take nearly four months to reach the intended L1 point.
The Aditya-L1 payloads are expected to provide the most crucial information to understand the problems of coronal heating, Coronal mass ejection (CME), pre-flare, and flare activities, and their characteristics, dynamics, and space weather.
The primary payload of Aditya-L1 the Visible Emission Line Coronagraph would be sending 1,440 images per day to the ground station for analysis on reaching the intended orbit.
Payload to send 1,440 images per day
The Visible Emission Line Coronagraph (VELC), the primary payload of Aditya L1 will be sending 1,440 images per day to the ground station for analysis on reaching the intended orbit.
“From the continuum channel, which is the imaging channel, an image will come — one image per minute. So approximately 1,440 images for 24 hours, we will be receiving at the ground station,” Aditya L1 Project Scientist and Operation Manager for VELC Dr Muthu Priyal said.
She said, IIA will host the VELC Payload Operations Centre (POC), which will receive raw data from ISRO’s Indian Space Science Data Centre (ISSDC), process them further to make it suitable for scientific analysis, and send it back to ISSDC for dissemination.
According to IIA officials, 190 kg VELC payload will send images for five years, which is the nominal life of the satellite, but it could last long depending on the fuel consumption, etc.
First images to be available by February-end
“The satellite is expected to be put into orbit in the middle of January and then we will do the test if all the systems are working properly and by the end of February we expect to get the regular data. It will take time and we have to test instrument by instrument. First we will test the smaller instruments, and the VELC’s shutter will be opened last, by mid of February,” Prof Jagdev Singh said.
‘Study of solar quakes must as they affect geomagnetic field’
A top scientist said the monitoring of the Sun on a 24-hour basis is a must to study solar quakes which can alter the geomagnetic fields of earth.
Explaining the need to study the Sun, Professor and In-Charge Scientist at the Indian Institute of Astrophysics (IIA), Dr R Ramesh told PTI that just as there are earthquakes on Earth, there are something called solar quakes – called as Coronal Mass Ejections (CMEs) – on the surface of the Sun.
In this process, millions and millions of tons of solar materials are thrown into the interplanetary space, he said, adding these CMEs can travel at a speed of approximately 3,000 km per second.
ISRO Chief offers prayers at Chengalamma temple
Ahead of India’s Aditya-L1 solar mission, ISRO Chairman S Somanath on Friday visited the Sri Chengalamma Parameshwari temple in Sullurpeta in the run-up to the launch of Aditya-L1 mission and prayed for its success.