Latest news with #AlexandreCorreira
Time of India
11-07-2025
- Science
- Time of India
Sun rises in the west and sets in the east: Why does Venus have an opposite spin?
When we look up at the sky, the planets seem to follow predictable paths. But not Venus. Our neighboring planet has long been one of the solar system's most mysterious worlds. It is well known for its toxic atmosphere, surface temperatures hot enough to melt lead, and thick clouds of sulfuric acid. Venus isn't just inhospitable, it's also astronomically strange, and one of its most interesting things about it is that it spins in the opposite direction to most planets, including Earth. Apart from this, another interesting aspect is that a single day on Venus lasts longer than its year, which means that Venus takes around 243 Earth days to complete one full spin on its axis, but only about 224 Earth days to orbit the Sun. That means a Venusian 'day' is longer than its entire 'year.' The planet where the sun rises in the west Unlike Earth and most other planets in the solar system, Venus rotates from east to west. That means, if you could stand on its surface, you'd see the sun rise in the west and set in the east. This kind of backward rotation is called 'retrograde rotation.' For a long time, scientists believed Venus originally spun in the same direction as the rest of the planets but later flipped upside down. The idea was that Venus's axis tilted a full 180 degrees, causing the rotation to appear reversed when viewed from space. According to Nature, earlier theories suggested that this flip could have happened due to powerful atmospheric tides. The tides that are driven by the sun's gravitational pull on Venus's thick atmosphere may have caused friction between the planet's core and mantle, eventually triggering the complete axis reversal. Maybe the axis didn't flip at all However, researchers Alexandre Correira and Jacques Laskar from the French research institute Astronomie et Systemes Dynamiques give a completely different view of this theory. In a paper published in Nature, they propose that Venus may not have flipped upside down. Instead, 'its rotation slowed to a standstill and then reversed direction.' Using computer simulations that considered solar tides, atmospheric friction, and gravitational pulls from other planets, the team showed that Venus could have naturally shifted into a retrograde state without needing to flip its axis. Their study revealed that Venus's spin is influenced by several possible rotational states, which includes two in a forward direction and two in a reverse direction. 'The researchers add that Venus would be more stable in one of the two retrograde rotational states,' reports Nature. Possibly, Venus was likely destined to spin backward at some point, it was just a matter of time.
The Star
01-07-2025
- Science
- The Star
QuickCheck: Is there a planet in our solar system that spins the wrong way?
The planet Venus is the second planet from the sun and is almost equal in size and mass with our planet, Earth. - pix by JAXA/ISAS/DARTS/Kevin M. Gill (CC BY 2.0) PETALING JAYA: The sun rises from the east, and sets in the west - this is a well-established fact for the longest time, and this is due to Earth's rotation, which is moving from west to east on its rotation. While planets in our solar system move one way, is it true that there's a planet moving in the opposite direction? Verdict: TRUE While the other planets are rotating in the same direction, only one planet is going against the flow - and that is Venus. The second planet from the sun, has a retrograde motion - which means that the orbital or rotational motion of Venus is going in the opposite direction on its axis. The initial theory of why Venus does this is that it initially spun in the same direction as most other planets and it simply flipped its axis 180 degrees at some point. Scientists have argued that the sun's gravitational pull on the planet's very dense atmosphere could have caused strong atmospheric tides. However, in 2000, a team of scientists from the French research institute Astronomie et Systemes Dynamiques proposed a new explanation. Scientists Alexandre Correira and Jacques Laskar suggested that Venus may not have flipped at all. According to the report published in Nature, they propose instead that its rotation slowed to a standstill and then reversed direction. Taking into account the factors mentioned above, as well as tidal effects from other planets, the team concluded that Venus's axis could have shifted to a variety of positions throughout the planet's evolution. Another theory is that Venus, also known as Earth's twin planet, could have been hit by a giant asteroid, leaving it spinning the other way. While large asteroids have hit Earth during its history (one of the theories as to how the Moon formed), it seems like a plausible idea that, during the early stages of the Solar System, Venus could have been hit by a celestial object that is similar in size to itself causing it to spin backwards. If this collision also altered Venus' orbit, the presence of the Sun, Mercury and Earth in this solar system would have pulled its orbit back to its original position. Another fun fact is that because of Venus' slow rotation, one Venus day is about 243 Earth days or close to eight Earth months. With this trivia, have a good (Earth) day. References: 1. science/venus-spins-backwards 2. article/why-venus-spins-the- wrong/
