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A new study has uncovered a mechanism that could solve a long-standing mystery about decaying planetary orbits around stars like our Sun.
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A new study has uncovered a mechanism that could solve a long-standing mystery about decaying planetary orbits around stars like our Sun.
Planetary scientists at the University of Colorado Boulder have discovered how Venus, Earth’s scalding and uninhabitable neighbor, became so dry.
The new study fills in a big gap in what the researchers call “the water story on Venus.” Using computer simulations, the team found that hydrogen atoms in the planet’s atmosphere go whizzing into space through a process known as “dissociative recombination”—causing Venus to lose roughly twice as much water every day compared to previous estimates.
In a recent publication, the experts offer a new explanation for this behavior. They propose that a “natal kick” – a displacement during formation due to asymmetric mass loss observed in white dwarfs – might be responsible for the dynamics that lead to these celestial bodies consuming nearby planetesimals.
The team’s computer simulations showed that in 80% of scenarios, this kick resulted in the elongation and alignment of the orbits of comets and asteroids within 30 to 240 astronomical units of the white dwarf. Remarkably, about 40% of the consumed planetesimals originated from retrograde, or counter-rotating, orbits.
Researchers using NASA’s James Webb Space Telescope may have detected atmospheric gases surrounding 55 Cancri e, a hot rocky exoplanet 41 light-years from Earth. This is the best evidence to date for the existence of any rocky planet atmosphere outside our solar system.
Renyu Hu from NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, is lead author on a paper published today in Nature. “Webb is pushing the frontiers of exoplanet characterization to rocky planets,” Hu said. “It is truly enabling a new type of science.”
The team thinks that the gases blanketing 55 Cancri e would be bubbling out from the interior, rather than being present ever since the planet formed. “The primary atmosphere would be long gone because of the high temperature and intense radiation from the star,” said Bello-Arufe. “This would be a secondary atmosphere that is continuously replenished by the magma ocean. Magma is not just crystals and liquid rock; there’s a lot of dissolved gas in it, too.”
As the article says absolutely no chance of life as rocky is a poor choice of words as the surface is probably a molten sea of magma.If true Flyaway this will quite possibly be the discovery of the century so far. Next step try to find out if 55 Cancri e has any prospects of alien life on the surface and to see how much Oxygen and Nitrogen the atmosphere has.
That settles it.The system sounds like a music box if you run the video.
Six planets in resonance in the constellation 'Coma Berenices'
Most people associate octaves, fifths and fourths with harmonic sounds whose frequencies are in a well-defined, whole-number ratio – 2:1 for the octave, 3:2 for the fifth and 4:3 for the fourth.www.dlr.de
An international team led by researchers from the EXOTIC Laboratory of the University of Liège, in collaboration with MIT and the Astrophysics Institute in Andalusia, has just discovered WASP-193b, an extraordinarily low-density giant planet orbiting a distant Sun-like star.
This new planet, located 1,200 light-years from Earth, is 50% larger than Jupiter but seven times less massive, giving it an extremely low density comparable to that of cotton candy. "WASP-193b is the second least dense planet discovered to date, after Kepler-51d, which is much smaller," explains Khalid Barkaoui, a Postdcotral Researcher at ULiège's EXOTIC Laboratory and first author of the article published in Nature Astronomy. Its extremely low density makes it a real anomaly among the more than five thousand exoplanets discovered to date. This extremely-low-density cannot be reproduced by standard models of irradiated gas giants, even under the unrealistic assumption of a coreless structure.”
Astronomers have discovered an Earth-size planet orbiting an ultracool red dwarf star similar in size to Jupiter. The red dwarf, located some 55 light-years away, is 100 times less bright than the sun and exhibits half the temperature of our star.
This new extrasolar planet, or exoplanet, is named SPECULOOS-3 and represents just the second time astronomers have discovered a planetary system around a red dwarf star, the first being the Trappist-1 system.
Social media became flooded late Saturday with viral videos of a large blue-green fireball streaking across the sky over Portugal, lighting up the night. Now the European Space Agency (ESA) says the meteor appears to have been a small part of a bigger, icy body impacting Earth’s atmosphere.
“It appears that this object was a small piece of a comet,” ESA wrote on X Sunday. “We estimate that it flew over Spain and Portugal travelling at ~45 km/s before burning up over the Atlantic Ocean at an altitude of ~60 km.”
A surprisingly low amount of methane and a super-sized core hide within the cotton candy–like planet WASP-107 b.
The revelations, based on data obtained by the James Webb Space Telescope, mark the first measurements of an exoplanet's core mass and will likely underpin future studies of planetary atmospheres and interiors, a key aspect in the search for habitable worlds beyond our solar system.
By 4.3 billion years ago, Earth’s crust may have already looked much like it does today. This is the earliest time some researchers think the plates of our planet’s crust began to slide against, over, and under each other in a process known as plate tectonics. How the very first instance of subduction—a key part of plate tectonics—occurred is still debated.
In a new study, Yuan et al. find evidence tracing the first subduction event to the same impact that created our Moon. The giant impact hypothesis theorizes that early in its history, Earth was struck by another planetary body about the size of Mars, sending a large chunk of rock—the Moon—into orbit.
Using the Keck II telescope in Hawaii, astronomers have observed a nearby brown dwarf known as HD 33632 Ab. Results of the observational campaign, presented in a paper published May 14 on the pre-print server arXiv, provide more insights into the properties of this substellar object and its atmosphere.
Previously unpublished photos of Mars' moon Phobos hint that the mysterious satellite may actually be a trapped comet — or perhaps just a piece of one, along with its twin moon Deimos.
Taken by high-resolution cameras onboard the Mars Express spacecraft, a European Space Agency (ESA) orbiter that has studied Mars and its moons since 2003, these 300-odd images exquisitely document Phobos' features. That includes the 9-kilometer-wide (5.6-mile-wide) Stickney crater, Phobos' largest landmark.
Fornasier and her colleagues used the snapshots to analyze the intensity of sunlight Phobos reflected from different angles. This technique, called photometry, allowed them to determine how much light Phobos reflected when the sun was right in front or at an offset angle.
The study's findings have implications for Deimos, too. Fornasier noted that if Phobos was once a comet, Deimos may have been one as well. In fact, based on the study, her team suggests the two moons may have once been joined together as a single bilobed comet that was trapped and eventually torn apart by Mars' gravity. In other words, Mars’ twin moons may actually be two halves of a single whole.