In recent news, the new Chairman of the Indian Space Research Organization (ISRO) announced their plans to launch a mission to Venus by December 2024. This mission will delve into the study of Venus’ atmosphere—a toxic and corrosive environment enveloped in clouds of sulfuric acid. Prior to this, the National Aeronautics and Space Administration (NASA) had already unveiled plans for two robotic missions, DaVinci Plus and Veritas, targeting the same planet.
Objectives of the Venus Mission
The primary aim of ISRO’s Venus mission is to explore various aspects of Venus that have not previously been investigated. The main objectives include:
1. Investigation of surface processes and shallow subsurface stratigraphy—this marks the first time an examination of Venus’ subsurface will be undertaken. Stratigraphy, a field of geology studying layering in rock formations, is a key focus in this study.
2. Study of the structure, composition and dynamics of Venus’ atmosphere.
3. Analysis of solar wind interaction with the Venusian ionosphere.
Significance of the Mission
This mission to Venus is more than just another scientific endeavor—it holds numerous implications for our understanding of Earth-like planets and consequently, the modelling of Earth’s climate. Its significance lies in the opportunities it presents to learn:
1. How Earth-like planets evolve over time.
2. The kind of conditions that exist on Earth-sized exoplanets, i.e., planets that orbit a star other than the Sun.
3. How dramatically a planet’s climate can change, providing valuable insights that could shape how we approach the issue of climate change on Earth.
Mission Challenges
Venus, with its dense, active atmosphere, poses unique challenges for exploration that make it a complex planet to study. The mission’s instruments need to be capable of penetrating deep into the atmosphere to acquire the necessary data. To this end, ISRO plans to employ a high-resolution Synthetic Aperture Radar (SAR) on the spacecraft; this instrument will allow researchers to study Venus’ surface regardless of the clouds surrounding the planet. SAR’s precise capabilities allow it to penetrate cloud cover and darkness and collect data in any weather, at any time of the day or night.
A Review of Previous Venus Missions
The journey to explore Venus isn’t new—several nations have sent missions to study the planet. Here’s a quick overview:
1. US: Sent Mariner series between 1962-1974, Pioneer Venus 1 and Pioneer Venus 2 in 1978, and Magellan in 1989.
2. Russia: Launched Venera series of spacecrafts between 1967-1983, followed by Vega 1 and 2 in 1985.
3. Japan: Launched Akatsuki in 2015.
4. Europe: Sent Venus Express in 2005.
About Venus
Named after the Roman goddess of love and beauty, Venus is the second planet from the Sun and sixth in size and mass in our solar system. It owns the title of the second brightest natural object in the night sky, after the Moon. Unique among planets in our solar system, Venus and Uranus spin clockwise on their axis. With a high concentration of carbon dioxide, Venus has the hottest planetary atmosphere in our solar system due to the intense greenhouse effect it causes. Interestingly, a day on Venus is longer than a year—it takes the planet 243 Earth days to rotate once on its axis and only 224.7 Earth days to complete one orbit of the Sun. Due to the similarities in their masses, sizes, densities, and relative locations in the solar system, Venus has often been referred to as Earth’s twin. The atmospheric pressure on Venus is 90 times that of Earth, making it the closest large body to Earth other than the Moon.
