As ISRO nears launch of Aditya-L1 mission, a look at what went into it and why it matters

Indian Institute of Astrophysics (IIA) has handed over a crucial paylo of itya-L1 solar observatory to ISRO before launch of India's first mission dedicated to studying sun. itya-L1 has been years in making owing to its complexity, scale and quest for perfection that ISRO is kwn for. On January 26, IIA handed over a paylo named Visible Emission Line Coronagraph (VELC) ahe of mission's launch which is anticipated between June or July this year from Sriharikota aboard PSLV rocket. 

About itya L-1 mission

(Artist's representation of itya-L1 observatory; Im: ISRO)

name itya which translates to ' sun' was initially planned as a 400 kg class satellite with just one paylo-- VELC-- and was to be installed in a 800-km low earth orbit (LEO). Scientists in ISRO and ir collaborators, however, decided to scale up mission and it was upgred with half-a-dozen more instruments. With a total of seven paylos, mission will w be installed at first Lagrange Point (L1) 15 lakh km from Earth and thus name itya L-1. 

(A map of five Lagrange points; Im: NASA)

Why upgre? This is because Lagrange Point 1 (L1) offers vant of an obstructed view of sun as it is right between sun and Earth. Moreover, Lagrangian points are a favourite spot for scientists, especially for -based observatories, because y are gravitationally stable locations, which means higher fuel efficiency which in turn increases life-span of a craft re. 

itya-L1, instruments and mission objectives

solar observatory, India's first-ever, will carry a total of seven instruments each assigned a specific objective to unravel new secrets of sun. VELC, which weighs 90 kg, is heaviest paylo and it will be used to gar data on sun's corona, outermost layer of its blazing atmosphere. While solar surface temperature is estimated to be around 6,000°C, corona heats up to millions of degrees, and why this happens is a mystery to astromers. This paylo by IIA might offer ISRO a breakthrough and solve this mystery, making India first nation with answers to se questions.

 (itya-L1 being assembled at ISRO's facility; Im: ISRO)

complex project took engineers one-and-a-half deces to complete. "It has taken 15 years for VELC from concept to completion, and this period was needed for a complex system like this", ISRO chairman S Somanath said while elaborating need to study sun. 

"Both imaging and spectroscopic observations obtained by VELC paylo are key to study diagstic parameters of solar corona and dynamics as well as origin of coronal mass ejections and magnetic field measurements of solar corona,"  IIA said in an official report.

Apart from VELC, or six instruments that were later ded are Solar Ultraviolet Imaging Telescope, itya Solar Wind Particle Experiment, Plasma Analyser Pack for itya, Solar Low Energy X-ray Spectrometer, High Energy L1 Orbiting X-ray Spectrometer, and Magnetometer. All of m will collectively observe photosphere, chromosphere and outermost layers of sun to decode solar activities and how y affect  wear. 

Why does itya-L1 matter?

This mission, if successfully launched, will bring ISRO he-to-he with or ncies that have alrey launched ir solar missions and are trying to lift veil of many mysteries that are yet to be explained. US ncy NASA, for instance, has multiple missions dedicated to sun, Parker probe being one of m. It was recently hot in helines for becoming first craft to 'touch' sun. 

Launched on August 12, 2018, Parker has me several flybys near sun and is collecting data on corona and solar winds. NASA has ar solar orbiter which it built in collaboration with European ncy (ESA) and launched on February 20, 2020 to determine how sun affects wear.

(Artist's representation of Parker probe; Im: NASA)

On September 23, 2006, NASA launched ar solar observatory named 'Hide' in partnership with Japan Aero Exploration ncy (JAXA) to find out what powers solar atmosphere and drives solar eruptions. Installed at an altitude of 650 km in a sun-synchrous orbit, orbiter has instruments to measure strength and direction of sun's magnetic field on sun's surface which is called protosphere.

(Artist's representation of NASA-ESA orbiter; Im: NASA)

China too is in race as it successfully deployed its massive vanced -based Solar Observatory (ASO-) on October 10, 2022. Nicknamed 'Kuafu-1', Chinese observatory weighs 888 kg and is deployed at an altitude of 720 km in a sun-synchrous orbit and is designed to last at least four years. Despite numerous missions alrey scrutinising sun, fact that ISRO's Mangalyaan was first to make new discoveries on Mars outracing wide range of or orbiters and rovers, shows itya-L1's promise.