India is ready to launch its first mission to study the Sun, Aditya L1, on September 2 from the Satish Dhawan Space Centre at Sriharikota. The mission aims to improve our understanding of the Sun’s dynamics and space weather, which can affect communication, navigation and power systems on Earth.
Aditya L1 is a spacecraft that will be placed in a halo orbit around the first Lagrange (L1) point of the Sun-Earth system, which is about 1.5 million km from Earth. This orbit will allow the spacecraft to have a continuous view of the Sun without any interference from the Earth or the Moon.
The spacecraft carries seven payloads (instruments) that will observe the photosphere, chromosphere and the outermost layers of the Sun (the corona) using electromagnetic and particle and magnetic field detectors. The payloads are:
- Visible Emission Line Coronagraph (VELC): It will study the origin and evolution of coronal mass ejections, which are huge eruptions of plasma from the Sun that can affect Earth’s magnetosphere and atmosphere.
- Solar Ultraviolet Imaging Telescope (SUIT): It will image the Sun in ultraviolet wavelengths to study the variations in solar irradiance, which is the amount of energy emitted by the Sun.
- Aditya Solar wind Particle Experiment (ASPEX): It will measure the properties of solar wind particles, such as their speed, density and temperature.
- Plasma Analyser Package for Aditya (PAPA): It will measure the distribution and composition of electrons and ions in the solar wind.
- Solar Low Energy X-ray Spectrometer (SoLEXS): It will monitor the X-ray flares from the Sun, which are sudden bursts of high-energy radiation that can affect satellites and astronauts in space.
- High Energy L1 Orbiting X-ray Spectrometer (HEL1OS): It will measure the high-energy X-ray emission from the Sun, which can provide information about the heating and acceleration mechanisms in the corona.
- Magnetometer: It will measure the magnitude and direction of the interplanetary magnetic field, which is carried by the solar wind and influences Earth’s magnetic field.
Aditya L1 is expected to have a mission life of five years. The mission will provide valuable data for solar physics research and space weather forecasting. It will also contribute to international efforts to understand the Sun and its impact on our planet.
Aditya L1 was planned in 2008 but faced several delays due to technical challenges and budget constraints. The mission was originally conceived as a small satellite with only one payload (VELC), but later expanded to include six more payloads. The mission cost is estimated at Rs 378 crore.
Aditya L1 is India’s second major space science mission after Chandrayaan-3, which successfully landed on the Moon in January 2023. India has also announced plans to launch missions to Venus, Mars and asteroids in the future.