The Indian Space Research Organisation (ISRO) launched the Aditya-L1 solar observatory

ISRO executed a key manoeuvre on Saturday, and successfully placed the Aditya-L1 spacecraft, India's first space-based solar observatory, to its final orbit Lagrange Point 1 location approximately 15 lakh kilometres away from Earth.

It was Prime Minister Narendra Modi who broke the news first on the internet of the success of Aditya-L1 mission. ISRO as usual drew a blank and was not present anywhere on the internet or the mainstream media to provide viewers the live updates/information they were keenly looking for on the status of the crucial manoeuvre. CNN News-18 however ran a live show and informed the viewers that the mission had succeeded. Great work indeed from this News Network.

What Is Lagrange Point 1?

Lagrange Point 1, or L1 point, represents one of the five equilibrium positions in the Earth-Sun system. At this point, gravitational forces from both bodies counteract the centrifugal force experienced by a smaller object, enabling it to maintain a stable position.

Within the Earth-Sun system, Lagrange Point 1 (L1) specifically resides between the Earth and the Sun, approximately 15 lakh kilometres away from Earth, in the direction facing the Sun.

Why ISRO Placed Aditya-L1 At Lagrange point 1?

ISRO  positioned Aditya-L1 at Lagrange Point 1 (L1) due to the unique stability offered by this point in the Earth-Sun system. The gravitational forces at L1 create a stable environment, making it an ideal location for scientific observations and space missions, ensuring relative stability with respect to the larger celestial bodies. Aditya-L1 will provide crucial insights into solar mysteries. Now that it has reached Lagrange Point 1, Aditya-L1 will be able to view the sun without any eclipses.

What are objectives of Aditya-L1?

The major scientific objectives of the Aditya-L1 mission are:

• Study of the Solar upper atmospheric (chromosphere and corona) dynamics.
• Study of chromospheric and coronal heating, physics of the partially ionised plasma, initiation of the coronal mass ejections, and flares.
• Observe the in-situ particle and plasma environment, providing data for the study of particle dynamics from the Sun.
• Physics of the solar corona and its heating mechanism.
• Diagnostics of the coronal and coronal loops plasma: Temperature, velocity and density.
• Development, dynamics and origin of coronal mass ejections (CMEs).
• Identify the sequence of processes that occur at multiple layers (chromosphere, base and extended corona) which eventually leads to solar eruptive events.
• Magnetic field topology and magnetic field measurements in the solar corona.
• Drivers for space weather (origin, composition and dynamics of solar wind).

Aditya-L1’S 127 Days Journey Into The Space: A Detailed Timeline

• January 6: ISRO inserted Aditya-L1 spacecraft in a complex manoeuvre in the halo orbit around Lagrange Point 1.
• December 8: In-orbit health status check of Plasma Analyser Package for Aditya (PAPA). SUIT payload captures full-disk images of the Sun in near ultraviolet wavelengths.
• December 1: Solar Wind Ion Spectrometer (SWIS) in the Aditya Solar Wind Particle Experiment (ASPEX) payload becomes operational.
• November 7: HELIOS captures the first High-Energy X-ray glimpse of Solar Flares.
• October 8: Trajectory Correction Manoeuvre (TCM) performed to ensure the spacecraft is on its intended path towards Halo orbit insertion around L1.
• September 30: Spacecraft escapes Earth's influence, en route to Sun-Earth Lagrange Point 1 (L1).
• September 25: Assessment of space situation around Sun-Earth Lagrange Point L1.
• September 19: Spacecraft travels to Sun-Earth L1 point. Commencement of scientific data collection.
• September 18: Fourth Earth-bound manoeuvre (EBN#4) performed successfully, achieving a new orbit of 256 km x 121973 km.
• September 10: Third Earth-bound manoeuvre (EBN#3) performed successfully, attaining a new orbit of 296 km x 71767 km.
• September 05: Second Earth-bound manoeuvre (EBN#2) performed successfully, achieving a new orbit of 282 km x 40225 km.
• September 03: First Earth-bound manoeuvre (EBN#1) performed successfully, placing the satellite in a new orbit of 245 km x 22459 km.
• September 02: India's first solar observatory, Aditya-L1, begins its journey to the Sun-Earth L1 point, placed precisely into its intended orbit by the successful launch of PSLV-C57.