NASA shares interesting facts about 'Earth's sister Venus' on National Siblings Day

On National Siblings day, NASA shared interesting facts about the second planet from the Sun and Earth’s closest planetary neighbour, Venus. “Like human sisters, Earth and Venus share a lot — similar mass, size, composition,” NASA explained in an Instagram post. It added that like human sisters, the Earth and Venus’ natures “can clash wildly,” adding that Venus’s atmosphere would “burn and crush us” but Earth is the “perfect home”.  According to NASA, Venus spins in the opposite direction from most of the planets in the solar system. A thick atmosphere traps heat in a runaway greenhouse effect, which makes the Earth’s neighbour “the hottest planet” in the entire solar system.

However, planet Venus is called Earth’s twin, due to the many similarities it shares in terms of size and structure to Earth, NASA explains in a release. “These are not identical twins, however – there are radical differences between the two worlds,” the space agency explained. Contrary to the Earth, Venus hosts a thick, toxic atmosphere filled which is abundant in carbon dioxide. venus’ atmosphere, according to NASA, is perpetually shrouded in thick, yellowish clouds of mostly sulfuric acid that trap heat and make the planet’s temperature extremely harsh for the humans to inhabit. “It’s the hottest planet in our solar system, even though Mercury is closer to the Sun,” NASA explained. Moreover, planet Venus has extremely “crushing air pressure” at its surface which is an estimated 90 times that of the Earth. This is exactly like the pressure a diver would encounter a mile below the ocean on Earth.

[This Magellan image is centered at 74.6 degrees north latitude and 177.3 east longitude, in the northeastern Atalanta Region of Venus. Image Credit: NASA/JPL]

Venus 'rotates backward'

NASA’s Mariner 2 explored the Earth’s twin planet on December 14, 1962. The first-ever planet visited by NASA mission was, in fact, Venus. NASA’s Magellan mapped the planet's surface with radar. NASA found that with a radius of 3,760 miles (6,052 kilometers), Venus is roughly the same size as Earth — just slightly smaller. It is also one of just two planets that rotate from east to west. Only Venus and Uranus have "backward" rotation in the entire solar system. “Sun doesn't rise and set each day on Venus as it does on Earth,” NASA said. “On Venus, one day-night cycle takes 117 Earth days because Venus rotates in the direction opposite of its orbital revolution around the Sun,” it explained. In structure, however, Venus is similar to Earth as it is approximately 2,000 miles (3,200 kilometers) in radius.

[The hemispheric view of Venus, as revealed by more than a decade of radar investigations culminating in the 1990-1994 Magellan mission, is centered at 180 degrees east longitude. Image Credit: NASA/JPL/USGS]