Fast-Spinning Exoplanet B Pictoris Beta Has 8 Hour Days
People on Earth who complain about there not being enough time in the day would have it rough on the exoplanet beta Pictoris B, which spins around its axis so fast a day lasts only 8 hours.
The super-fast spin of the distant planet is even faster than Jupiter, which rotates in just 10 hours.
By using data collected from the world's most advanced visible-light astronomical observatory, the Very Large Telescope in Chile, a team of Dutch astronomers were able to employ a novel strategy for calculating planetary rotation.
Writing in the journal Nature, the scientists report that they relied on the specific colors of light absorbed by carbon monoxide gas in the exoplanet's atmosphere.
"Think of these absorption lines as black lines in the rainbow of color from the exoplanet," Popular Mechanics explained. Some of the lines were oddly broader than scientists expected, a function of the Doppler effect. The shifting carbon monoxide measurements allowed scientists to calculate that beta Pictoris B is rotating at a rate of about 15.5 miles per second.
That's about 60,000 mph, roughly double the spin rate of Jupiter. Earth is a comparative slowpoke, spinning at just 1,040 mph.
Beta Pictoris b is a young planet, only about 20 million years old, but its size - 16 times larger and 3,000 times as massive as Earth - dwarfs our home planet.
In time, the planet is expected to cool and shrink, causing it to spin even more rapidly, according to Netherlands Institute for Space Research.
"We came up with these observations as a kind of test for the method," lead researcher Ignas Snellen, with Leiden University, Netherlands, told Discovery News. "It will be extremely powerful with the next-generation of telescopes, like the European Extremely Large Telescope, and may even allow us to probe Earth-like planets in the habitable zone of nearby stars."