In news- NASA recently announced two missions to Venus, as part of its ‘Discovery Program’ that aims to explore and study the solar system.
About the two new missions-
- The VERITAS (Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy) mission will map the surface of the planet in 3D and study its geology.
- It will also study infrared emissions from the surface to map various kinds of rocks.
- It hunts for volcanic activity and tries to find out if any active volcanoes are releasing water vapour into the atmosphere, sustaining its greenhouse effect.
- The DAVINCI+ (Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging) will study the dense atmosphere of Venus to understand the trigger and evolution of the runaway greenhouse effect active on the planet.
- The mission will also try to determine if the planet held an ocean of liquid water in the past.
- The mission will return the first high-resolution images of unique surface features known as “tesserae” on Venus, which are akin to the continents on Earth, and suggest the existence of plate tectonics.
- The mission’s accompanying Plus probe will drop into the atmosphere, making measurements of noble gas composition in the layers.
- The “ultra-precise” Deep Space Atomic Clock-2 will be tested on VERITAS while the Compact Ultraviolet to Visible Imaging Spectrometer (CUVIS) will fly with DAVINCI+ to make high-resolution UV measurements.
- The missions are funded for $500 million each and are expected to launch somewhere around 2028-2030.
About Venus-
- Venus is often called Earth’s twin because of similar mass, size, gravity, surface composition and complex atmospheric processes.
- For those on Earth, Venus is the second-brightest object in the sky after the moon.
- It appears bright because of its thick cloud cover that reflects and scatters light.
- The planet’s thick atmosphere traps heat and is the reason that it is the hottest planet in the solar system with a surface temperature of 500C- high enough to melt lead.
- Venus moves forward on its orbit around the Sun but spins backwards around its axis slowly, which means on Venus the Sun rises in the west and sets in the East.
- One day on Venus is equivalent to 243 Earth days because of its backward spinning.
- Venus does not have any moons, a distinction it shares only with Mercury among the planets in the Solar System.
- It is also known as the “morning star” and “evening star”.
Venus orbiters include-
- Mariner 2 (1962),
- Soviet Venera (1967) (( first successful probe to enter and return data from another planet)),
- Venera 7 lander (1970), the first craft to successfully land on another planet,
- Venera 8 (1974),
- Venera 9 & Venera 10 (1975),
- Pioneer Venus (1978), the first orbiter around Venus and carried the first radar to observe another planet,
- The most recent observations of Venus are from the Galileo spacecraft, which flew past Venus in February 1990 on its roundabout journey to Jupiter.
- On November 9th of 2005, the European Space Agency’s Venus Express mission was launched on a Russian rocket, with support from NASA.
- The Cassini Orbiter, which orbited Saturn until September 2017, also observed Venus briefly and sent home some useful data.
As of now, Japan’s Akatsuki mission is studying the planet from Orbit.
About Shukrayaan-
- Shukrayaan-1 is a proposed orbiter to Venus by the Indian Space Research Organisation (ISRO) to study the surface and atmosphere of Venus.
- The mission concept to Venus was first presented at a Tirupati space meet in 2012.
- From 2016 to 2017, ISRO collaborated with JAXA to study the Venus atmosphere using signals from the Akatsuki in a radio occultation experiment.
- The three broad research areas of interest for this mission include surface/subsurface stratigraphy and re-surfacing processes; study of atmospheric chemistry, dynamics and compositional variations; study of solar irradiance and solar wind interaction with Venus ionosphere.
- ISRO and France (CNES) are holding discussions to collaborate on this mission and jointly develop autonomous navigation and aerobraking technologies.
- The science payload would have a mass of 100 kg and would consist of instruments from India and other countries.