ARIES-led study finds the Sun's upper atmosphere rotates faster than its visible surface
A study by ARIES, USO-PRL and Ahmednagar College, announced on 30 July 2026, found that the Sun's atmosphere rotates faster than its visible surface and that rotation speed increases with height.
Summary
Researchers from the Aryabhatta Research Institute of Observational Sciences (ARIES, an autonomous institute of DST), Udaipur Solar Observatory of the Physical Research Laboratory and Ahmednagar College found, using the Nobeyama Radioheliograph in Japan, that the Sun's atmosphere spins faster than its visible surface, with speed rising with height – unlike the conservation-of-angular-momentum behaviour seen in Earth's atmosphere. Rotation slows slightly when sunspot activity is stronger. The work, published in Astronomy & Astrophysics, can improve space-weather models.
Key facts
- Finding
- Sun's atmosphere rotates faster than its surface; speed rises with height
- Institutes
- ARIES (DST), USO-PRL, Ahmednagar College
- Instrument
- Nobeyama Radioheliograph, Japan
- Journal
- Astronomy & Astrophysics
- Use
- Better solar activity and space-weather models
Practice MCQs 2 questions
A July 2026 study by Indian researchers found that the Sun's atmosphere rotates faster than its surface. Which telescope's observations did they use?
Show answer
Correct answer: A — Nobeyama Radioheliograph, Japan
The ARIES-led team used observations from the Nobeyama Radioheliograph in Japan.
Consider the following statements about the July 2026 study on the Sun's atmosphere: 1. The rotation speed of the Sun's atmosphere increases with height above the surface. 2. The rotation becomes faster when sunspot activity is stronger. Which of the statements given above is/are correct?
Show answer
Correct answer: A — 1 only
The study found the rotation speed increases with height and decreases slightly when solar activity (sunspot number) becomes stronger.