India to launch its first mission to Venus in 2028: Everything you need to know

Sub: Sci

Sec: Space sector

Context:

The Union Cabinet approved India’s first mission to Venus which ISRO aims to launch in March 2028.
This is the country’s second interplanetary mission after the Mars Orbiter Mission launched in 2013.

Overview of India’s Venus Mission (Shukrayaan):

ISRO will be responsible for the development of spacecraft and its launch.
It will be an orbiter missione., the spacecraft will be sent into an orbit around Venus, to study the planet from a distance.
Objective: To explore the surface and sub-surface of Venus, its atmosphere and its interaction with the Sun.
Optimal Launch Window: Earth and Venus align for the shortest path every 19 months. The mission is expected to be accomplished on the opportunity available during March 2028.
Payload: Scientific payloads include a high-resolution Synthetic Aperture Radar, thermal cameras
Trajectory: Similar to previous Indian space missions, the satellite will gain speed in Earth’s orbit, will get sling-shot towards Venus, and then get captured in its orbit.
Travel Duration: Once launched, it will take about 140 days to reach Venus after exiting Earth’s orbit.
Initial Orbit: Satellite will be placed in a highly elliptical orbit of 500 km x 60,000 km around Venus. This high orbit is unsuitable for conducting scientific experiments.
Target Orbits: The goal is to lower the satellite to either a 300 x 300 km or 200 x 600 km orbit, based on payload requirements. This will be done using Aero-breaking.

Aero-Braking:

Aerobraking is a technique used in space missions that involves using a planet’s atmosphere to slow down a spacecraft by creating drag, enabling manoeuvres such as orbit adjustments.

Why is it important to study Venus?

Venus is often called Earth’s twin because it is similar in mass, density, and size. Therefore, studying Venus can provide insights into the evolution of Earth.
Venus is thought to have had water at some point in its history but has now become a dry and dusty planet.

Differences between Earth and Venus:

Venus has extremely high surface temperature of around 462⁰C, making it hotter than Mercury. Scientists think this is because of a runaway greenhouse effect.
- It is thought that the water present on the Venusian surface evaporated because of the proximity of the planet to the Sun. As water vapour is a greenhouse gas, it led to the planet trapping more heat and further evaporating water from its surface.
- These hot temperatures are the reason why no lander to Venus has survived for more than a couple of hours.
The atmospheric pressure on Venus is much higher than on Earth. It is almost similar to the pressure felt underneath the oceans on Earth.
5% of the atmosphere of Venus is made up of carbon dioxide and there are sulphuric acid clouds on the planet.
Venus rotates very slowly on its axis as compared to Earth. One rotation of Venus lasts around 243 Earth days.

Other Venus missions:

There have been several missions to Venus in the past by US, Russia, Japan, and a collaborative mission of the European Space Agency (ESA) with Japan.
Future missions:
- US missions DaVinci in 2029 and Veritas in 2031
- EnVision mission of ESA for 2030