Very accurate radio observations took 15 years, but astronomers are now able to measure very well how fast Venus rotates, meaning we know how long a day has been on Earth’s fiery twin. One Venus day is equivalent to 243.0226 Earth days, or about two thirds of the Earth year – and will change with about 20 minutes of change.The results are reported in Nature Astronomy.
It may seem surprising that we don’t know the exact timing of Venus’ days because the planets are adjacent. It is easy to calculate the rotational speed of most planets if they have identifiable properties on their surface. The gas giant is more difficult. But fortunately, Jupiter has a giant red cyclone to follow. Venus̵7; thick atmosphere complicates the search, so astronomers have to be creative in measuring it.
Between 2006 and 2020, astronomers used a 70-meter-wide Goldstone antenna in California’s Mojave Desert to send radio waves to Venus. These waves can travel through the atmosphere and then reflect from the surface. Several minutes later, they would be picked up again at the Goldstone Observatory, then about 20 seconds later at the Greenbank Observatory in West Virginia. The obvious difference between the two senses tells the team how fast the planets spin.
“We used the Venus as a giant disco ball,” said UCLA lead author Jean-Luc Margot in a statement. “We lit it with a very powerful flashlight – about 100,000 times brighter than a conventional flashlight. Disco, we can summarize the properties about the spin. [state]. ”
Experiments sounded a lot easier than in real life. Earth and Venus must be in proper form, and both radio observatories must work for the observations to be successful. Twenty-one observations were finally made over 15 years.
“We found it difficult to get everything to work properly in 30 seconds,” Margot said. But it’s unusual for us to get all the information we were hoping to get. ”
The variation in birthday length is due to the movement of Venus’ dense atmosphere. At the surface level, the pressure is about 93 times higher than that of Earth, so its tilt affects the planet’s rotation.
The observations also revealed more about Venus. The team was able to estimate that the planet’s core is approximately 3,500 kilometers (2,175 miles) apart, similar in size to that of Earth. However, from the current knowledge we do not know if it is a liquid, solid or a mixture.
The research also provided a better measure of axial tilt relative to the planets’ orbital plane. They found that the end of Venus was on either side at 2.64 degrees, an improvement from the previous estimate, with a 10x accuracy considering the minute’s tilt, the planet would not experience seasonality. The tilt of the Earth is about 23 degrees, unlike the much smaller Venus tilt. But Venus is unique among planets as it rotates in the opposite direction, causing some strange impacts.
Telling the time on Venus is very strange. The planet’s rotation takes 243 days, but its years (the rotation of the Sun) only 225 days.However, since the rotation in the opposite direction, if we count the days from dawn to dawn, it will last only 117 days. The mind that this odd planet still hides many mysteries.
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