Aditya-L1 Solar Probe – UPSC Prelims S&T

02 April, 2021 CIISCO Algorithm- Aditya-L1 Solar probe – UPSC Prelims S&T

Coronal Mass Ejections (CMEs) Identification in Inner Solar Corona (CIISCO) algorithm will be used in India’s first solar mission, Aditya-L1. CIISCO was developed by the Aryabhatta Research Institute of observational sciences (ARIES) and Royal Observatory of Belgium.

This new algorithm will be used to detect and track the accelerating Coronal Mass Ejections (CMEs) in the lower corona of the Sun. Previously, Computer Aided CME Tracking Software (CACTus) based on a computer vision algorithm was used to detect and characterise such eruptions.

This vision algorithm detects the CMEs automatically in the outer corona where these eruptions cease to show accelerations and propagate with a nearly constant speed. However, this algorithm could not be applied to the inner corona observations due to the vast acceleration experienced by these eruptions.

Coronal Mass Ejections

Coronal Mass Ejections (CMEs) that comes from the Sun are huge bubbles of gas threaded with magnetic field lines. They cause various disturbances to the space environment, and cause geomagnetic storms, satellite failures, and power outages. Aditya-L1

Aditya-L1 Mission is India’s first solar mission planned by the Indian Space Research Organisation (ISRO). Earlier the name was Aditya -1, which has been renamed as Aditya-L1 Mission.

It is ISRO’s second space-based astronomy mission after AstroSat for a scientific expedition to study the Sun. The mission was initially named Aditya 1 which was limited to observing only the solar corona.

AstroSat

AstroSat, was launched in September, 2015, by PSLV-C30 from Sriharikota (Andhra Pradesh).

It is the first dedicated Indian astronomy mission aimed at studying celestial sources in X-ray, optical and UV spectral bands simultaneously. Objective: is to study Sun’s Corona, Chromosphere and Photosphere. In addition, it will study the particle flux emanating from Sun, and the variation of magnetic field strength.

Aditya L1 Mission

It was launched using the Polar Satellite Launch Vehicle (PSLV) XL Mission Aditya L1 comprises few moving components which may be a cause of collision in space Given below is a list of payloads which have been used for the mission: Visible Emission Line Coronagraph (VELC) Solar Ultraviolet Imaging Telescope (SUIT) Aditya Solar wind Particle Experiment (ASPEX) Plasma Analyser Package for Aditya Solar Low Energy X-ray Spectrometer (SoLEXS) High Energy L1 Orbiting X-ray Spectrometer (HEL1OS) Magnetometer The main objective of the Aditya L1 Mission is that it will help in tracking Earth- directed storms and predict its impact through solar observations

Why did ISRO Rename Aditya 1 Mission as Aditya L1 Mission?

Aditya-1 mission was planned for observing only the Corona of Sun. The reason behind Corona getting heated to very high temperatures is still a mystery in Solar Physics. Aditya -1 mission involved placing the satellite in 800 Km low earth orbit. Later ISRO planned to place the satellite in the halo orbit around the Lagrangian Point (L1). L1 is 1.5 Million Km from the Earth. This point provides the advantage of observing the Sun continuously without any disturbance. Hence the mission was renamed as Aditya L1 mission.

What is the Visible Emission Line Coronagraph (VELC)?

It is an internally occluded solar coronagraph capable of simultaneous imaging, spectroscopy, and spectro-polarimetry close to the solar limb.

What are the observations expected from Aditya L1?

Observations on the following:

Sun’s photosphere (soft and solid X-rays)

Chromosphere (UV) and

Corona (visual and NIR)

Lagrange Point 1

Lagrange Points, named after Italian-French mathematician Josephy-Louis Lagrange, are positions in space where the gravitational forces of a two- body system (like the Sun and the Earth) produce enhanced regions of attraction and repulsion. The L1 point is about 1.5 million km from Earth, or about 1/100th of the way to the Sun. L1 refers to Lagrangian/Lagrange Point 1, one of 5 points in the orbital plane of the Earth-Sun system. These can be used by spacecraft to reduce fuel consumption needed to remain in position. A Satellite placed in the halo orbit around the Lagrangian point 1 (L1) has the major advantage of continuously viewing the Sun without any occultation/ eclipses. The L1 point is home to the Solar and Heliospheric Observatory Satellite (SOHO), an international collaboration project of National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA).

Other Missions to the Sun

1. NASA’s Parker Solar Probe’s aim is to trace how energy and heat move through the Sun’s corona and to study the source of the solar wind’s acceleration. It is part of NASA’s ‘Living With a Star’ programme that explores different aspects of the Sun-Earth system. 2. The earlier Helios 2 solar probe, a joint venture between NASA and space agency of erstwhile West Germany, went within 43 million km of the Sun’s surface in 1976.