Kelly Kizer Whitt has been a science writer specializing in astronomy for more than two decades. She began her career at Astronomy Magazine, and she has made regular contributions to AstronomyToday and the Sierra Club, among other outlets. Her children's picture book, Solar System Forecast, was published in 2012. She has also written a young adult dystopian novel titled A Different Sky. When she is not reading or writing about astronomy and staring up at the stars, she enjoys traveling to the national parks, creating crossword puzzles, running, tennis, and paddleboarding. Kelly lives with her family in Wisconsin.
May 5, 2021
Scientists have used radio waves to precisely measure Venus’ spin rate and tilt on its axis. We knew the Venus day was exceedingly long, but now we know that the length of a day on Venus regularly changes in length!
The thick cloud cover of Venus – which is impenetrable in visible light – has made it tough for astronomers to measure the length of the planet’s day. A new study at radio wavelengths may have some answers. Image via NASA/ JPL-Caltech.
Scientists said that they’ve finally answered the question of the length of a “day” on Venus. And the answer is … it’s always changing, by as much as 20 minutes! We knew that Venus had an exceedingly long day. A day on Venus – a single spin of the planet on its axis – is equal to approximately 243 Earth-days. What’s new is that the length of a Venus-day doesn’t stay fixed. That is, the spin of this neighboring planet regularly speeds up and slows down, by an amount measured in only minutes on earthly