Astronomers using the W. M. Keck Observatory in Hawaii have made a startling finding: a distant exoplanet with a tail hundreds of thousands of miles long. Planet WASP-69 b is located 164 light-years away, and as it orbit, it is followed by a stream of escaping gas that forms a tail — making it look a little like a comet.
The planet is a type called a hot Jupiter, meaning it is a large gas giant that orbits very close to its star. So close, in fact, that a year there lasts less than four days and it has a blistering temperature of over 600 degrees Celsius.
This close proximity to the star also causes its most distinctive feature, the tail. Radiation from the star bombards the atmosphere of the planet, stripping away gases like hydrogen and helium. And as streams of particles from the star called stellar winds hit the planet, they pull these escaping gases into a tail shape. The tail has been observed to be more than 7.5 times the radius of the planet, meaning that it stretches for over 350,000 miles.
But it could be even longer as the researchers didn’t have enough telescope time to observe the full length of the tail. However, because it is formed by stellar winds, the tail could also shrink over time if the wind lessens.
“If the stellar wind were to taper down, then you could imagine that the planet is still losing some of its atmosphere, but it just isn’t getting shaped into the tail,” explained lead researcher Dakotah Tyler of the University of California, Los Angeles. “But if you crank up the stellar wind, that atmosphere then gets sculpted into a tail.”
The process of planets losing their atmospheres over time is a common one, and is thought to be comparable to what happened to planets like Mars in our solar system. But the shaping of a tail is unusual. However, even though WASP-69 b is losing a lot of gas, at 200,000 tons per second, because it is so large and massive, it will not be totally stripped any time soon — so the unusual tailed planet should continue to exist for thousands of years to come.
The research is published in The Astrophysical Journal.
After 13 suborbital test flights and more than $15 billion in development costs, SpaceX's Starship has finally reached orbit. The 407-foot megarocket, the most powerful ever built, lifted off from Starbase, Texas, on Monday and delivered its first real payload on it's 14th attempt. The celebration came with an asterisk, though, since SpaceX had to cut the planned 10-hour mission to roughly three hours.
https://twitter.com/SpaceX/status/2104601695711904180
SpaceX is finally ready to give Starship its biggest test yet. The company says the massive rocket's 14th test flight is scheduled for September 22, when it will attempt to put the upper stage into Earth orbit for the first time. The launch is currently pending regulatory approval, with a 75-minute window opening at 7:15 a.m. CT.
Starship has 26 Starlink satellites to deliver
For decades, humanity has looked up at the Moon and wondered what it would be like to live on it. Think sprawling cities, factories, research centers, and permanent human settlements. Unfortunately, there is one fairly fundamental problem with that vision.
A new study published in Frontiers in Space Technologies argues that even the Moon's potentially enormous reserves of frozen water may be nowhere near enough to support city-sized populations sustainably. Researchers Martin Elvis and Jonathan McDowell estimate that the permanently shadowed regions near the lunar poles could contain roughly one billion tons of water. It sounds like an extraordinary amount until you put a million thirsty humans next to it.