- Why in news
- On 3 November 2026, PIB reported that IIA scientists used VELC on Aditya-L1 with NASA SDO data to show that a CME of 5 August 2024 expanded asymmetrically. The study appeared in Astrophysical Journal Letters.
- What it is
- Aditya-L1 is India's first space-based solar observatory, run by ISRO. It sits at the Sun-Earth L1 point and watches the Sun continuously. Its main payload, VELC, is a coronagraph that studies the solar corona and early coronal mass eruptions.
- Launch and position
- Aditya-L1 was launched in September 2023 and now operates at the Sun-Earth L1 point, giving continuous views of the Sun.
- Payloads
- It carries 7 payloads. VELC is the primary one, an internally occulted coronagraph.
- VELC spectroscopy
- VELC studies nascent CMEs through the 530.3 nm green emission line of highly ionized iron in the corona.
- Who built VELC
- VELC was designed and fabricated by IIA at its MGK Menon Lab for Space Sciences on the CREST campus in Hosakote, with ISRO support.
- Key finding
- The CME did not expand like a symmetric bubble. It expanded non-uniformly and took an asymmetric shape, which can alter its speed towards Earth.
- IIA status
- IIA is an autonomous institution under the Department of Science and Technology.
Don’t confuse with L1 point vs Earth orbit: Aditya-L1 is placed near the Sun-Earth L1 point, not in an orbit around Earth or the Sun itself.
Don’t confuse with CME vs solar flare: A CME is a large ejection of plasma and magnetic field from the corona. A solar flare is a burst of radiation. They can occur together but are different.
Science and technology: 57 Prelims questions since 2013; most test the concept behind the news, not the news itself. In Mains, 12 news-triggered questions.
Why it matters
- Better CME models improve forecasts of arrival time and speed, protecting satellites and communication networks.
- Shows indigenous instrument capability, as VELC was built in India by IIA with ISRO support.
Problems
- CMEs evolve fast in the lower corona, and line-of-sight motion cannot be obtained from imaging alone.
- Reconstructing CMEs often needs multi-viewpoint imaging from several space telescopes.
Way forward
- Apply the VELC spectroscopic and 3-D modelling technique to more CMEs.
- Combine VELC data with other space observatories to improve space-weather forecasting.
Put in your answer
Aditya-L1 VELC study: IIA scientists, using VELC and NASA SDO data, showed for the first time that a CME expanded asymmetrically, which affects its arrival time at Earth.
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UPSC’s own questions that come close to this issue, from our Prelims and Mains banks.
No practice question for this one; the card may still help an answer. Why: Space missions are a standing Prelims topic (science and tech is 17% of news-linked questions), but this finding is a research detail with no testable provisions.
Worth revising until Prelims 2028: most news questions come within two years of the event.