By now, we have discovered hundreds of stars with multiple planets orbiting them scattered throughout the galaxy. Each one is unique, but a system orbiting the star HD 158259, 88 light-years away, is truly special.
The star itself is about the same mass and a little larger than the Sun - a minority in our exoplanet hunts. It's orbited by six planets: a super-Earth and five mini-Neptunes.
After monitoring it for seven years, astronomers have discovered that all six of those planets are orbiting HD 158259 in almost perfect orbital resonance. This discovery could help us to better understand the mechanisms of planetary system formation, and how they end up in the configurations we see.
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SpaceX seeks FCC permission for operating all first-gen Starlink in lower orbit - SpaceNews.com
SpaceX has touted lower altitudes as a key element of its plans to prevent space debris, since gravity will pull dead satellites below 650 kilometers into Earth's atmosphere within 25 years.
The bulk of SpaceX's planned constellation — a second-generation system of 7,500 V-band satellites the company has yet to start launching — are already cleared by the FCC for orbits between 335 and 346 kilometers.
The April 17 request is SpaceX's third time in 12 months seeking FCC permission to change its approved constellation architecture since the FCC first cleared the company in 2018 to provide service with the 12,000-satellite megaconstellation.
An Earth-Sized World Orbiting in its Star's Habitable Zone Was Found in Older Kepler Data -
To date, astronomers have confirmed the existence of 4,144 extrasolar planets in 3,074 systems , with a further 5,094 candidates awaiting confirmation. The majority of these planets were found by the Kepler Space Telescope , which spent nine years (between May of 2009 and February of 2018) monitoring distant stars for transit signals – where a planet passing in front of a star causes a dip in brightness.
And yet, even though it is now defunct, the data that Kepler accumulated over the years continues to lead to new discoveries. For instance, a transatlantic team of researchers recently found a signal in Kepler ‘s archival data that eluded detection before. This signal indicates that there is a second planet orbiting Kepler-1649, an M-type red dwarf star located 302 light-years away.
Self-isolation champions fresh home from a jaunt in orbit wonder if they've returned to the wrong
"We've returned to a very different planet," observed NASA astronaut Jessica Meir as the Expedition 62 trio came home on 17 April . The Soyuz MS-15 crew included Oleg Skripochka and NASA astronaut Andrew Morgan, who had originally launched on Soyuz MS-13.
A little shuffling had been required to allow UAE "spaceflight participant" or "visiting astronaut" Hazza Al Mansouri to spend a week aboard the ISS after launching with Meir and Skripochka on MS-15. Al Mansouri returned on MS-12 and the need to accommodate his stay coupled with the fallout from the aborted Soyuz MS-10 in 2018 meant Morgan and fellow NASA 'naut Christina Koch enjoyed longer stays aboard the ISS than originally planned.
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NASA Space Station On-Orbit Status 20 April, 2020 - Electrostatic Levitation Furnace Research -
The three-member Expedition 63 crew is beginning its first full workweek and kicking off science aboard the International Space Station.
More space traffic continues this week, as Russia gets ready to launch its next Progress resupply ship late Friday.
NASA astronaut Chris Cassidy is on his third spaceflight and is in command of the orbiting lab. His two crewmates, Roscosmos cosmonauts Anatoly Ivanishin and Ivan Vagner, will be with Cassidy until October.
Einstein Was Right: Star Orbiting a Black Hole Proves It | Digital Trends
Astronomers have observed a star “dancing” around the supermassive black hole at the heart of our galaxy, Sagittarius A* , in an orbit that confirms Einstein’s theory of general relativity.
Einstein’s theory of relativity overrode the previous model of gravity laid down by Newton. Newton’s theory stated that gravity is a force of attraction between two massive objects, and that this force acted instantaneously. But Einstein contradicted that, saying that gravity was not really a force but was rather a curvature of space-time.
Just Three Orbiting Black Holes Can Break Time-Reversal Symmetry, Physicists Find
Most of the laws of physics don’t care which direction time is travelling. Forwards, backwards… either way, the laws work exactly the same. Newtonian physics, general relativity – time is irrelevant to the mathematics: This is called time-reversal symmetry.
In the real Universe, things get a bit messier. And now a team of scientists led by astronomer Tjarda Boekholt of the University of Aveiro in Portugal have shown that it takes as few as three gravitationally interacting bodies to break time-reversal symmetry.
Scientists observe celestial smash-up around nearby star - Reuters
The apparent crash between two icy bodies each about 125 miles (200 km) wide occurred around a star called Fomalhaut, located a relatively close 25 light-years from Earth, that is about twice the mass and 17 times the luminosity of the sun, the researchers said. A light year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km).
The two parties in this celestial smash-up may have been objects called planetesimals that are thought to join together to eventually form planets during a planetary system’s formative stages though in this case the two were destroyed.
Happening on Twitter
Astronomers find planet similar to Earth. Cool, but at this point we need to find a planet that's quite a bit different from Earth. 22_Minutes (from Canada) Sat Apr 18 14:22:51 +0000 2020
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