Introduction
The sun has been a source of fascination and study for humans for thousands of years. Ancient civilizations, such as the Egyptians and the Mayans, worshipped the sun as a deity and tracked its movements for agricultural and spiritual purposes. In the modern era, the study of the sun has taken on a new importance, with scientists seeking to understand the sun's effects on Earth's climate, its magnetic fields, and its potential for generating solar energy.
The Indian Space Research Organization (ISRO) has been at the forefront of studying the sun and its effects on Earth. ISRO has launched several satellites to study the sun's behavior, including the Aditya-L1 mission, which is set to launch in 2022. Aditya-L1 will study the sun's corona, which is the outermost layer of the sun's atmosphere, and will provide valuable insights into the sun's behavior and its potential effects on Earth. Now Let's take a closer look at the ISRO mission details with AEROGO!
Aditya L1 Mission: Exploring the Sun
Aditya-L1 is a satellite designed solely to explore the Sun, with 7 distinct payloads that were developed indigenously in India – 5 by ISRO and 2 by Indian academic institutions in collaboration with ISRO. The name Aditya means "Sun" in Sanskrit.
Main objectives
Coronal heating and solar wind acceleration.
Initiation of Coronal Mass Ejection (CME), flares, and near-earth space weather.
Coupling and dynamics of the solar atmosphere.
Solar wind distribution and temperature anisotropy
L1 in Aditya refers to Lagrange Point 1 of the Sun-Earth system. L1 is a space location where the gravitational forces of two celestial bodies, such as the Sun and Earth, are in balance, allowing an object placed there to remain relatively stable concerning both celestial bodies.
Here are some interesting facts about L1 that you may find intriguing:
What are Lagrange Points?
Lagrange points are five points in space where the gravitational pull of two large celestial bodies, such as the Earth and the Moon or the Sun and Jupiter, balance the centrifugal force felt by a much smaller object, such as a satellite or spacecraft. These points are located along the line connecting the two large celestial bodies and form equilateral triangles with the two celestial bodies.
The three Lagrange points that lie along the line connecting the two celestial bodies are known as L1, L2, and L3. The L1 point is particularly important because a spacecraft placed at this point can maintain a fixed position relative to both celestial bodies, making it an ideal location for solar observatories and communication satellites. The other two Lagrange points, L4 and L5, form equilateral triangles with the two celestial bodies and are stable points where objects can remain relatively stationary. Since our solar mission, Aditya is planned to be placed in the L1 orbit, let's know about it in detail.
L1 is located about 1.5 million kilometers (about 930,000 miles) from Earth towards the Sun.
It is also known as the libration point, as objects placed there have a slight amount of wiggle room due to the complex gravitational interactions between the Sun and Earth.
L1 is a popular location for spacecraft to be placed to observe the Sun and study space weather. There are several missions currently utilizing L1.
In addition to spacecraft, L1 could also be a potential location for future space habitats. With a stable environment and constant sunlight, it could be an ideal spot for studying the cosmos or even serving as a launch point for further exploration.
However, there are also challenges associated with L1. One major concern is the potential for space debris to accumulate in the region, which could pose a threat to any objects placed there. Additionally, the complex gravitational forces can make it difficult to maintain a stable orbit around L1.
Strategy and Benefits of Aditya-L1
Aditya-L1 is a remarkable satellite that will enable scientists to gather invaluable information about the Sun's outer atmosphere.
Some of the additional features and benefits of this satellite are:
Aditya-L1 is equipped with several advanced instruments, including a coronagraph, which will enable scientists to observe the Sun's corona with unprecedented detail. The outermost layer of the sun's atmosphere is known as the Corona, which plays a crucial role in the Sun's activity and behavior. By studying the corona, scientists can better understand phenomena such as solar flares, coronal mass ejections, and other space weather events that can impact Earth.
Aditya-L1 will be located approximately 1.5 million km away from Earth, which is only about 1% of the Earth-Sun distance. This distance will allow the satellite to study the Sun's outer atmosphere without getting too close to the Sun, which would be dangerous and impractical too.
The L1 point's gravitational stability will minimize the need for frequent orbital maintenance efforts, ensuring that the satellite can operate efficiently for an extended period.
The data gathered by Aditya-L1 will be invaluable for a wide range of scientific applications, including space weather forecasting, solar physics research, and heliophysics studies. This information will help scientists better understand the Sun's behavior and activity, which has important implications for our understanding of the solar system and our ability to predict and prepare for space weather events that can impact Earth.
Launch of Aditya-L1
On September 2, 2023, Aditya-L1 is scheduled to launch and remain in Earth-bound orbits for 16 days, during which it undergoes 5 maneuvers to gain the necessary velocity for its journey. This velocity makes it push forward toward outer space. It helps Aditya-L1 to overcome the escape velocity of the earth. Subsequently, Aditya-L1 undergoes a Trans-Lagrangian insertion maneuver, marking the beginning of its 110-day trajectory to the destination around the L1 Lagrange point. Upon arrival at the L1 point, another maneuver binds Aditya-L1 to an orbit around L1, a balanced gravitational location between the Earth and the Sun. The satellite spends its whole mission orbiting around L1 in an irregularly shaped orbit in a plane roughly perpendicular to the line joining the Earth and the Sun.
The mission will be launched by ISRO’s PSLV XL rocket from Satish Dhawan Space Centre SHAR (SDSC-SHAR), Sriharikota. Initially, the spacecraft will be placed in a Low Earth Orbit. Subsequently, the orbit will be made more elliptical, and later the spacecraft will be launched towards the Lagrange point (L1) by using onboard propulsion. As the spacecraft travels towards L1, it will exit the Earth’s gravitational Sphere of Influence (SOI). After exit from SOI, the cruise phase will start and subsequently, the spacecraft will be injected into a large halo orbit around L1. The total travel time from launch to L1 would take about four months for Aditya-L1. The Trajectory of the Aditya-L1 mission is shown in the figure.
Payloads
The spacecraft has seven scientific payloads that aim to systematically study the Sun. All payloads are developed indigenously in collaboration with various ISRO Centres.
VELC:
The Visible Emission Line Coronagraph is designed to observe the solar corona and coronal mass ejections' dynamics. The payload is developed by the Indian Institute of Astrophysics, Bengaluru, in close collaboration with ISRO.
SUIT:
The Solar Ultra-violet Imaging Telescope is intended to capture images of the Solar Photosphere and Chromosphere in near Ultra-violet (UV). It also measures the solar irradiance variations in near UV. The payload is developed by the Inter-University Centre for Astronomy and Astrophysics, Pune, in close collaboration with ISRO.
SoLEXS and HEL10S:
The Solar Low Energy X-ray Spectrometer and High Energy L1 Orbiting X-ray Spectrometer are designed to analyze X-ray flares emitted by the Sun over a wide X-ray energy range. Both payloads are developed at the U R Rao Satellite Centre, Bengaluru.
ASPEX and PAPA:
The Aditya Solar Wind Particle Experiment and Plasma Analyser Package for Aditya payloads are designed to study the solar wind and energetic ions and their energy distribution. ASPEX is developed at the Physical Research Laboratory, Ahmedabad. PAPA, on the other hand, is developed at the Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram.
MAG:
The Magnetometer payload can measure interplanetary magnetic fields at the L1 point. The payload is developed at the Laboratory for Electro-Optics Systems, Bengaluru.
Advancement and Uniqueness of Aditya-L1
New developments have allowed for the first-time spatially resolved solar disk in the near UV band, which has led to a better understanding of Coronal Mass Ejection (CME) dynamics close to the solar disk (from ~1.05 solar radius). This provides insight into the acceleration regime of CME, which has not been consistently observed before. Additionally, onboard intelligence is being used to detect CMEs and solar flares to optimize observations and data volume. Lastly, multi-direction observations are being used to study the directional and energy anisotropy of solar wind.
Conclusion
In conclusion, the ADITYA-L1 mission represents a significant milestone for the Indian Space Research Organization (ISRO) and the nation as a whole. By exploring the sun's corona and studying solar flares, this mission has the potential to greatly improve our understanding of the sun's behavior and its impact on Earth. Additionally, the mission showcases India's growing capabilities in space exploration and technology development, which will undoubtedly lead to many more exciting missions in the future. As we look forward to the launch of ADITYA-L1, we can be confident that ISRO will continue to push the boundaries of space exploration and make important contributions to our understanding of the universe. Stay connected with AEROGO to get to know more about Space technology, aeromodelling, and Drone technology.
