“The essence of science is independent thinking, hard work and not equipment,” said Sir C.V. Raman, an Indian Physicist. ISRO has proved it to be true and successfully landed the Chandrayaan-3 at the ShivaShakti point on the moon’s South pole, making India the first country to land at the moon’s south pole. Chandrayaan-3 proved that a space mission can be done with less budget than a space sci-fi movie like Interstellar.
Building on the momentum of their monumental achievement with the moon’s south pole, ISRO now sets its sights even higher, aiming for the heart of our solar system: the Sun.
2nd September 2023, at 11.50 a.m., the mission to Sun Aditya-L1 would be launched from Sriharikota. As ISRO is all set for the next mission, let us peek into the mission and why it is crucial.
Our nearest Star – The Sun
Layers of the Sun
Image credits: nasa.gov
The Sun is the centre of our solar system, holding the solar system together with its gravity. It is the nearest star to us, a hot glowing ball of hydrogen and helium. It releases energy and burns through fusion, in which hydrogen atoms combine to form helium atoms. The Sun is vital for life to exist on Earth.
It is approximately 4.5 billion years old and 150 million kilometres from Earth. The central region of the Sun is known as the ‘core’. The temperature at the core can reach as high as 15 million degrees Celsius, making nuclear fusion possible. The visible surface of the Sun, known as the photosphere, is relatively cool and has a temperature of about 5,500°C.
Sun influences the weather of Earth. Sun is a dynamic star and produces various explosive energy release methods like solar flares. Such eruptions and release of energy affect the near-earth space environment.
The Sun gives light and energy and influences the space weather.
The Sun ejects particles called protons, known as solar winds. Also, the solar system is filled with solar magnetic fields. It is impossible to study the space weather from Earth since the Earth’s atmosphere and magnetic field cover most of the solar light and its magnetic fields.
So studying the space weather and its influence from space is essential to know its effects on planets, including Earth.
Aditya-L1 is the first solar mission by India. It would travel 1.5 million km from Earth to study the Sun.
Illustration showcasing the L1 point’s strategic position between Earth and the Sun.
Image credits: ISRO
The spacecraft will be placed in a halo orbit around the point L1 shown in the image. A satellite placed in the halo orbit around the L1 point has the significant advantage of continuously viewing the Sun without any eclipse.
Did you know?
Meet the Lagrange Points! Imagine them as cosmic parking spots between big things like the Earth and the Sun. If you place a satellite there, it stays put with minimal fuel, saving a lot of energy!
Simply put, these spots balance the gravitational tug-of-war between large objects, making it easier for smaller things to stay. Curiously, there are five of these unique spots, labelled L1 to L5. For instance, L1 is pretty close to us, just 1% of the distance between Earth and the Sun.
Trajectory of Aditya-L1
The planned trajectory of Aditya-L1, detailing its journey from Earth to its destination in space.
Image credits: ISRO
The PSLV rocket will propel Aditya-L1 from Sriharikota into space, setting it on a path to the L1 point. This strategic point offers an uninterrupted view of the Sun, making it ideal for in-depth solar studies.
As shown in the image above, the spacecraft will first be in low Earth orbit. Gradually, with careful adjustments, it will be directed to a particular location in space named L1, as mentioned above. On its way to L1, it’ll move beyond the influence of Earth’s gravity. Once positioned at L1, it will trace a broad orbit. The entire journey from Earth to L1 is anticipated to take about four months.
Fun Fact: “Did you know? Our Sun is just one of about 100 billion stars in the Milky Way galaxy. Yet, despite being a ‘local star’, there’s so much we’re yet to learn about it. With missions like Aditya-L1, we inch closer to unravelling its mysteries.
Objectives of the Mission of Aditya–L1
ISRO has highlighted a few significant objectives of the mission:
- The Sun’s outer layer visible during solar eclipses is the Sun’s Corona. But surprisingly, it is around 400 to 500 times hotter than the surface. The temperature, which had to decrease gradually, increased at the corona. This is called coronal heating.
One of the main objectives is to study this coronal heating and the solar winds’ acceleration.
- Coronal mass ejections(CME) are large explosions of plasma and magnetic fields from the corona of the Sun. They expand and travel towards the planets. And solar flares, on the other hand, are the eruption of electromagnetic radiation.
The mission also aims to study the CMEs, flares and their impact on space weather.
- The solar atmosphere is full of gases, with magnetic fields also influencing the movement of the gases in the atmosphere. The solar flares and CMEs also affect the atmosphere and its dynamics.
The mission also aims to study the influences of magnetic coupling and solar atmosphere dynamics.
- The fourth but not the least is to study the distribution and temperature variations of the solar atmosphere.
Payloads of Aditya-L1
Aditya-L1 mission carries seven payloads or instruments to make different studies, observations and experiments.
Image credits: ISRO
ISRO’s relentless pursuit of space exploration, grounded in hard work and innovative thinking, exemplifies Sir C.V. Raman’s belief. With the launch of Aditya-L1, we’re not just reaching for the stars but also deepening our understanding of our very own star, the Sun. It’s a testament to what India and dedicated scientists can achieve, blending the essence of science with the spirit of exploration.
Watch the launch!
The launch of Aditya-L1 from Sriharikota can be watched live on the Doordarshan channel or ISRO’s YouTube channel.
Remember! ISRO will launch the mission at 11:50 a.m. (IST) on 2nd September.’