First science result from Aditya-L1 mission is out

The first science result from the Aditya-L1 mission, India’s first scientific mission dedicated to studying the Sun, is out.

Scientists who developed Visible Emission Line Coronagraph (VELC) onboard Aditya-L1 precisely estimated the onset time of a coronal mass ejection that erupted on the Sun on July 16. VELC is the spacecraft’s primary payload.

The Indian Space Research Organisation (ISRO) launched Aditya-L1 on September 2, 2023, from the Satish Dhawan Space Centre in Sriharikota. The spacecraft’s VELC payload was developed by the Indian Institute of Astrophysics (IIAp), Bengaluru.

The Sun is a very active object and often spews vast quantities of plasma in violent eruptions called coronal mass ejections (CMEs).

“These are the most powerful explosions happening in our solar system,” the team of IIAp scientists involved with the VELC’s operations said in a statement shared with The Hindu. “When a CME blows past the earth, it can damage the electronics in satellites in near-earth space and disrupt radio communication networks on the earth.”

The team added that using unique data obtained with the VELC payload, members could precisely estimate the onset time of a CME that erupted from the Sun on July 16.

The results of the study, by R. Ramesh, V. Muthupriyal, Jagdev Singh, K. Sasikumar Raja, P. Savarimuthu, and Priya Gavshinde, are set to be published in a forthcoming edition of the peer-reviewed journal Astrophysical Journal Letters.

A representative image of a coronal mass ejection on the Sun on August 31, 2012,. | Photo Credit: NASA/GSFC/SDO

According to the team’s statement, the study provides valuable insights into similar energetic eruptions on the Sun.

“Observation of the CMEs as they originate on the Sun and understanding their plasma characteristics is one of the major science goals for VELC, and we are happy that the instrument did exactly that,” R. Ramesh, senior professor at IIAp and the principal investigator of the VELC payload, told The Hindu.

Prof. Ramesh added that with the Sun approaching the maximum phase of its current solar cycle (no. 25), CMEs are expected to occur more frequently. So continuously monitoring the Sun with the VELC is expected to provide valuable scientific data.

“The CMEs are usually observed in visible continuum light only when they have propagated well away from the Sun’s surface. However, unique spectroscopic observations with the VELC like in our study, lets us study the CMEs very close to the solar surface itself for the first time,” study coauthor and IIAp project scientist Dr. Muthupriyal said.

According to Jagdev Singh, another coauthor, “Knowing the thermodynamic properties of the CMEs near the Sun are very important to understand their source regions on the Sun and VELC is precisely doing that.”

ISRO placed the Aditya-L1 spacecraft in a halo orbit around the first earth-Sun Lagrange point (or L1) on January 6, a little more than four months after its launch. The spacecraft has a mission life of five years.