Exoplanet’s Spin Detected For First Time — And It’s Fast
Planet β Pictoris b spins so fast, its day only lasts eight hours. NASA/Goddard Space Flight Center/F. Reddy
Time flies, you say to yourself all the time.
Well, here’s a little perspective: In a gassy planet about 65 light years away from Earth a day only lasts eight hours.
Scientists calculate that Planet β Pictoris b spins at about 56,000 miles per hour at its equator, faster than any planet in our solar system and about 50 times faster than Earth, even though the planet has a diameter that’s 16 times that of Earth and is 3,000 time heavier.
And, yes, that fills up with wonder. But the real news here is that scientists have been able to measure a far-aways planet’s spin for the first time.
The findings are detailed in the latest issue of Nature. The journal reports:
“Exoplanets are typically hidden by the glare of their parent star and can only be discovered indirectly, but β Pictoris b was one of the first to be found by direct imaging. This was possible because the massive planet, at around 20 million years of age, is relatively young and still warm, so it radiates strongly at infrared wavelengths. In addition, the star system is only about 20 parsecs (65 light years) from Earth — the star β Pictoris, part of the constellation Pictor in the southern sky, is visible to the naked eye — and the planet orbits a long way away from the star, about twice Jupiter’s distance from the Sun.
“Those properties, as well as the composition of the star and the planet, enabled [Ignas] Snellen’s team to home in on the infrared light from β Pictoris b, using the Very Large Telescope in the Atacama Desert of northern Chile. ‘It’s exciting to see another kind of insight into the properties of extrasolar planets,’ says astronomer Thayne Currie of the University of Toronto.”
The Journal has a pretty detailed explanation of how they calculated the spin, so click through if you’re curious. The short of it is that they looked at how “the infrared light is filtered by carbon monoxide in its atmosphere.”
Earlier this year, scientists also discovered a cloud of poisonous gas in that solar system. They think the cloud is created by “ongoing rapid-fire collisions among a swarm of icy, comet-like bodies.”