Context:
For years, scientists have thought that Venus is geologically dead. But a new research paper indicates that a volcano on the planet’s surface is still active.
Relevance:
GS I: Geography
Dimensions of the Article:
- New Discovery on Venus Volcano: What are the findings?
- About Venus
New Discovery on Venus Volcano: What are the findings?
Background:
- Scientists discovered new information about the Atla Regio area of Venus where two of the planet’s largest volcanoes, Ozza Mons and Maat Mons, are located.
Discovery:
- During the examination of images taken by NASA’s Magellan spacecraft between 1990 and 1992, a vent on the north side of a domed shield volcano was found to have changed significantly in shape and size between February and October 1991.
- The vent appeared nearly circular and deep with steep walls covering 2.6 sq km in the February image, but in the images taken eight months later, the same vent had become irregular in outline, shallower and nearly filled, covering about 3.9 sq km, indicating an eruption or flow of magma beneath the vent.
Challenges in Discovering:
- Magellan spacecraft’s radar images used for this discovery had lower resolution and were relatively coarse compared to images taken by cameras attached to spacecraft today.
- Also, Magellan changed its viewing geometry each time it flew over Venus, making it difficult to distinguish real changes from changes caused by different viewing geometry.
Future Implications:
- Volcanoes act as windows to provide information about a planet’s interior.
- The discovery takes scientists a step further to understand the geological conditions of Venus and other exoplanets.
- It also sets the stage for three new Venus missions, including the European EnVision orbiter and NASA’s DAVINCI and VERITAS missions, in the next decade. Herrick is part of both EnVision and VERITAS missions.
About Venus
- Venus is the second planet from the Sun and as the brightest natural object in Earth’s night sky after the Moon, Venus can cast shadows and can be, on rare occasions, visible to the naked eye in broad daylight.
- In Venus, the Sun rises in the west and sets in the east, because it rotates in the opposite direction (East to West/Clockwise) to all but Uranus.
- It has the densest atmosphere of the four terrestrial planets, consisting of more than 96% carbon dioxide. Because of this, the greenhouse effect on Venus is so strong that even though Mercury is closer to the Sun, Venus has the hottest surface of any planet in the Solar System.
- The atmospheric pressure at the planet’s surface is about 92 times the sea level pressure of Earth.
- Venus is shrouded by an opaque layer of highly reflective clouds of sulfuric acid, preventing its surface from being seen from space in visible light.
- The water has probably photo dissociated, and the free hydrogen has been swept into interplanetary space by the solar wind because of the lack of a planetary magnetic field.
- As one of the brightest objects in the sky, Venus has been a major fixture in human culture for as long as records have existed.
Observations and explorations of Venus
- Due to its proximity to Earth, Venus has been a prime target for early interplanetary exploration.
- It was the first planet beyond Earth visited by a spacecraft (Mariner 2 in 1962), and the first to be successfully landed on (by Venera 7 in 1970).
- Venus’s thick clouds render observation of its surface impossible in visible light, and the first detailed maps did not emerge until the arrival of the Magellan orbiter in 1991.
- Plans have been proposed for rovers or more complex missions, but they are hindered by Venus’s hostile surface conditions.
- Observations of the planet Venus include those in antiquity, telescopic observations, and from visiting spacecraft. Spacecraft have performed various flybys, orbits, and landings on Venus, including balloon probes that floated in the atmosphere of Venus.
- After the Moon, Venus was the second object in the Solar System to be explored by radar from the Earth.
- Ten Soviet probes have achieved a soft landing on the surface, with up to 110 minutes of communication from the surface, all without return.
- U.S.’s missions to Venus: Mariner series 1962-1974, Pioneer Venus 1 and Pioneer Venus 2 in 1978, Magellan in 1989.
- Russia’s mission to Venus: Venera series of space crafts 1967-1983, Vegas 1 and 2 in 1985.
- Japan’s Akatsuki was launched in 2010, however, the orbital insertion maneuver failed and the spacecraft was left in heliocentric orbit.
- Venus Express was a mission by the European Space Agency to study the atmosphere and surface characteristics of Venus from orbit.
Significance of Exploring Venus
- It will help to learn how Earth-like planets evolve and what conditions exist on Earth-sized exoplanets (planets that orbit a star other than our sun).
- It will help in modelling Earth’s climate, and serves as a cautionary tale on how dramatically a planet’s climate can change.
-Source: Indian Express
