WASP-193b, an unusually low-density giant planet orbiting a distant Sun-like star. It is about 1,200 light-years away from Earth and 50% larger than Jupiter, but seven times less massive. This low density is equivalent to the density of cotton candy
A team of scientists from Belgium, MIT and Spain has just discovered WASP-193b, an unusually low-density giant planet orbiting a distant Sun-like star. It is about 1,200 light-years away from Earth and 50% larger than Jupiter, but seven times less massive. This low density is equivalent to the density of cotton candy.
"WASP-193b is the second least dense planet discovered to date, after the much smaller Kepler‑51d," explains Khaled Barkawi, a postdoctoral fellow at the University of Liege and first author of the paper published in Nature Astronomy. Because of its very low density, it An exception among the more than 5,000 extrasolar planets discovered to date, this density cannot be generated using standard models of Gas giants are irradiated, even under the unrealistic assumption of a structure without a core."
The new planet was discovered by WIDE, an international collaboration of academic institutions that jointly operated two robotic observatories, one in the northern hemisphere and the other in the southern. Each used an array of wide-angle cameras to measure the brightness of thousands of individual stars across the sky.
In data collected in 2006 and 2008 and again from 2011 to 2012, the WASP South Observatory detected periodic dips in light from the star WASP-193. The astronomers determined that the periodic dips in the star's brightness correspond to a planet passing in front of the star every 6.25 days. The scientists measured the amount of light the planet blocked at each transit, which gave them an estimate of its size.
The team then used observatories located in Chile's Atacama Desert to measure the planet's signal at different wavelengths and verify that the obscuring object was a planet. They used spectroscopic observations collected from two other spectrographs in Chile to measure the planet's mass.
Much to their surprise, the cumulative measurements revealed that the density of the planet is very low. Its mass according to their calculations is 0.4 of the mass of Jupiter and the size is 1.5 times. The resulting density is about 0.059 grams per cubic centimeter.
Jupiter's density, on the other hand, is about 1.33 grams per cubic centimeter, and Earth's density is greater, 5.51 grams per cubic centimeter. One of the materials whose density is closest to the new inflated planet is cotton candy, which has a density of about 0.05 grams per cubic centimeter.
"The planet is so light, it's hard to think of a similar solid material," says Julien de Wit, co-author from MIT. The reason it is close to cotton candy is that they are both mostly air. The star is actually very airy."
The researchers believe that the new star consists mainly of hydrogen and helium, like most of the other gas giants in the galaxy. In WASP-193b, these gases probably create a very, very inflated atmosphere that extends tens of thousands of kilometers further than Jupiter's atmosphere. How exactly a planet can inflate so much is a question that no existing theory of planet formation has yet to answer. A large reservoir of energy deep in the planet's interior is certainly required, but the details of the mechanism are not yet understood.
One response
All these discoveries amuse me. Here is the next discovery: the star of the gays. A star that changes its colors every day. Its distance is like a map to the sky. Its specific density is like banana ice cream without sugar.