Indian researchers have made important discoveries on coronal mass ejections (CMEs) emanating from the Sun using Mission Aditya – L1, India’s first space-based solar observatory.
Key Discoveries and Observations
Coronal Mass Ejection (CME) event
- On July 16, 2024, a large CME was observed in the Sun’s outer atmosphere (corona).
- This event coincided with a powerful solar flare.
- The CME occurred on the western side of the Sun, which was observed using the VISIBLE Emission Line Coronagraph (VELC) instrument.
Coronal Dimming
- The brightness of the Sun’s corona decreased by about 50% during the CME.
- This brightness reduction occurs when a huge amount of plasma and magnetic fields are ejected from the Sun into space.
- The event lasted for about 6 hours, providing important information about the dynamic processes of the Sun.
- Increase in temperature and turbulence
- The temperature of the Sun’s corona increased by 30% during the CME.
- The plasma turbulence (thermal turbulence) was measured at a speed of 24.87 km/s, indicating intense magnetic activity.
- This turbulence suggests that there is a lot of energy present in the Sun’s magnetic field, which can affect space weather.
Doppler velocity measurements
- The expelled plasma was found to be red-shifted, moving away from the Sun at a speed of about 10 km/s.
- This shows that the Sun’s magnetic field bends the CME and changes its direction.
- This information will help in understanding how CMEs can affect Earth and other planets.
Scientific significance of the discovery
Understanding the structure of the Sun’s corona
- The temperature of the Sun’s outer layer (corona) is hotter than the Sun’s surface, which has always been a mystery.
- This study will help in understanding the mysterious nature of this layer of the Sun.
Space Weather Prediction
- Understanding the direction and impact of CMEs can lead to accurate prediction of space weather.
- It is essential for keeping Earth’s satellites, astronauts and communication systems safe.
Coronal Mass Ejection
- Coronal Mass Ejection (CME) is one of the largest explosions on the surface of the Sun that can contain a billion tons of matter at a speed of several million miles per hour into space.
Aditya – L1 Mission
- Launch date: September 2, 2023
- Installation: Installed at the L1 point in January 2024.
- Launch site: Satish Dhawan Space Centre, Sriharikota
- Location (L1): This point is located 15 lakh km from Earth, from where the mission can continuously monitor the Sun.
- Travel time: It took about 125 days to reach the L1 point.
- Space Observatory Mission: This is the second astronomical observatory mission of ISRO, the first mission was Astrosat (2015).
Objective of Mission
The main objective of the Aditya – L1 mission is to study the various layers of the Sun and its dynamic processes. Its main objectives are as follows
- Study of the solar corona: To study in detail the outermost layer (corona) of the Sun, which is hotter than the surface.
- Solar Wind: To study the stream of charged particles emanating from the Sun and how it affects the Earth’s atmosphere.
- Solar Flares: To investigate large explosions occurring from the surface of the Sun and understand their impact.
- Solar Radiation: To analyze the heat, light, and energy emanating from the Sun.
- Study of the magnetic field: To measure the powerful magnetic field of the Sun and its activities.
Importance
- Helps in understanding the effects of space weather and solar activities.
- Helpful in accurately predicting the effects of solar storms and radiation on Earth and other planets.