Aditya-L1 — named for Aditya, the Sun, and L1, the first Sun–Earth Lagrange point — is India's first space-based observatory dedicated to studying the Sun. It is operated by the Indian Space Research Organisation (ISRO).
Aditya-L1 was built to watch the Sun continuously and to answer long-standing puzzles about how our star works — and how its activity drives space weather across the Solar System.
From its vantage point at L1 it studies the Sun's visible surface (photosphere), the layer above it (chromosphere), and the outer atmosphere (corona), while sampling the solar wind and magnetic field streaming past the spacecraft. Together these observations help explain solar eruptions that can disturb satellites, power grids and communications on Earth.
Continuously observe the Sun's atmosphere and the solar wind from the uninterrupted vantage of the L1 point.
Understand coronal heating, coronal mass ejections, solar flares, the solar wind and the Sun's magnetic field, and their influence on space weather.
Launched on 2 September 2023 aboard a PSLV-C57 rocket from the Satish Dhawan Space Centre, Sriharikota, the spacecraft first circled Earth in a series of orbit-raising manoeuvres. On 19 September 2023 it performed a Trans-Lagrangian Point 1 Injection, leaving Earth's gravity for a cruise of about four months toward L1.
On 6 January 2024 — 126 days after launch — Aditya-L1 fired its thrusters and was captured into a halo orbit around L1, roughly 1.5 million kilometres from Earth. From here it needs only a whisper of fuel to stay on station, and enjoys a clear, eclipse-free view of the Sun.
The Sun is the engine of the Solar System — and an unpredictable one.
Solar flares and coronal mass ejections hurl radiation and charged particles into space. When they reach Earth they can knock out satellites, disrupt navigation and radio, endanger astronauts, and even damage power grids. Watching the Sun from L1 — upstream of Earth, above the blurring atmosphere — gives scientists an early, unbroken view of this activity as it develops.