From UPSC perspective, the following things are important :
Prelims level : Missions on Venus
Mains level : Planetory exploration
NASA has selected two missions to the planet Venus, Earth’s nearest neighbor. The missions are called DAVINCI+ and VERITAS.
DAVINCI+ and VERITAS
- DAVINCI+ is short for ‘Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging’ and is the first US-led mission to the planet’s atmosphere since 1978.
- It will try to understand Venus’ composition to see how the planet formed and evolved.
- This mission also consists of a decent sphere that will pass through the planet’s thick atmosphere and make observations and take measurements of noble gases and other elements.
- Significantly, this mission will also try to return the first high-resolution photographs of a geological feature that is unique to Venus.
- This feature, which is called “tesserae” may be comparable to Earth’s continents.
- The presence of tesseraes may suggest that Venus has tectonic plates like Earth.
- The second mission called VERITAS is short for ‘Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy’.
- It will map the planet’s surface to determine its geologic history and understand the reasons why it developed so differently from Earth.
- VERITAS will orbit Venus with a radar that will help to create a 3D reconstruction of its topography which might be able to tell scientists if processes such as plate tectonics and volcanism are still active there.
- This mission will also map the emissions from Venus’s surface that may help in determining the type of rocks that exist on Venus–a piece of information that is not exactly known yet.
- It will also determine if active volcanoes are releasing water vapor into the atmosphere.
Why study Venus?
- The results from DAVINCI+ are expected to reshape the understanding of terrestrial planet formation in the solar system and beyond.
- Taken together, both missions are expected to tell scientists more about the planet’s thick cloud cover and the volcanoes on its surface.
- Further, scientists speculate about the existence of life on Venus in its distant past and the possibility that life may exist in the top layers of its clouds where temperatures are less extreme.
Have humans visited Venus?
- Because of the planet’s harsh environment, no humans have visited it and even the spacecraft that have been sent to the planet have not survived for a very long time.
- Venus’ high surface temperatures overheat electronics in spacecraft in a short time, so it seems unlikely that a person could survive for long on the Venusian surface.
- So far, spacecraft from several nations have visited the planet.
- The first such spacecraft was the Soviet Union’s Venera series (the spacecraft, however, could not survive for long because of the planet’s harsh conditions).
- It was followed by NASA’s Magellan Mission that studied Venus from 1990-1994. As of now, Japan’s Akatsuki mission is studying the planet from Orbit.
- 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.
- Surface temperatures on Venus can go up to 471 degrees Celsius, which is hot enough to melt lead, NASA notes. Surface temperatures on Venus can go up to 471 degrees Celsius, which is hot enough to melt lead, NASA notes.
Some unknown facts
- While Venus, which is the second closest planet to the Sun, is called the Earth’s twin because of their similar sizes, the two planets have significant differences between them.
- For one, the planet’s thick atmosphere traps heat and is the reason that it is the hottest planet in the solar system, despite coming after Mercury, the closest planet to the Sun.
- Further, Venus moves forward on its orbit around the Sun but spins backwards around its axis slowly.
- This 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, opposite to that of the Earth’s and most other planets.
- Venus also does not have a moon and no rings.