As astronomers have brazzers sex videoused large telescopes to scan the skies for exoplanets, they've noted something odd: Worlds of a certain size are conspicuously missing in space.
The number of confirmed exoplanets — planets orbiting stars other than the sun — has risen to 5,539, according to NASA, with over 10,000 more candidates under review. But exoplanet hunters believe the universe is likely teeming with many trillions of planets.
These exoplanets come in different sizes. Of the midsize worlds, they are mostly divided into two groups, known as super-Earths and mini Neptunes (or sometimes sub-Neptunes). Although both kinds are larger than Earth and smaller than Neptune, super-Earths can be as much as 1.75 times the size of our home planet, and mini Neptunes are double to quadruple the size of Earth.
But if worlds were lined up in order of size, there would be a noticeable gap smack-dab in between super-Earths and mini Neptunes — planets that are about 1.5 to 2 times the size of Earth.
"Exoplanet scientists have enough data now to say that this gap is not a fluke," said Jessie Christiansen, an Infrared Processing and Analysis Center research scientist at Caltech, in a statement. "There’s something going on that impedes planets from reaching and/or staying at this size."
This Tweet is currently unavailable. It might be loading or has been removed.
The absent midsize planets are the focus of a new study published in The Astronomical Journal. Christiansen led the research team, which looked at the Milky Way star clusters Praesepe, sometimes known as the beehive, and Hyades, located on the face of the Taurus constellation, using NASA’s Kepler Space Telescope data.
The size gap could be caused by certain mini Neptunes actually shrinking over time. If such a world doesn’t have enough mass, and thus gravitational force, it could lose its atmosphere by its core emitting radiation that pushes the atmosphere away.
Over time, these less-massive mini Neptunes would shrink down to the size of a super-Earth. Scientists believe this could occur about 1 billion years into a planet's life.
Want more scienceand tech news delivered straight to your inbox? Sign up for Mashable's Light Speed newslettertoday.
"Exoplanet scientists have enough data now to say that this gap is not a fluke."
This Tweet is currently unavailable. It might be loading or has been removed.
But there's another possibility that could answer for this behavior. So-called photoevaporation, thought to occur in a planet’s first 100 million years, happens when a planet's atmosphere is blown away by the radiation of its host star, similar to what would happen if you pointed a hair dryer at an ice cube, Christiansen said.
The coauthors are leaning toward the first explanation — with the source of the radiation coming from within the planet's core — because the star systems they were observing are thought to be about 600 to 800 million years old. If photoevaporation were the cause, it likely would have happened hundreds of millions of years earlier, they figure, and the planets would have barely any atmospheres left to speak of.
But to put the question to bed, scientists will need to conduct several follow-up studies in the future to prove or disprove the researchers' findings.
(Editor: {typename type="name"/})
Wordle today: The answer and hints for February 22, 2025
How to watch 'The Last Showgirl': Now streaming
NYT Connections Sports Edition hints and answers for May 22: Tips to solve Connections #241
Tennessee vs. UCLA 2025 livestream: How to watch March Madness for free
Working From Home Effectively: Dos and Don'ts
Trump zeroes out Biden's funding for rural broadband access
Are More RAM Modules Better for Gaming? 4 x 4GB vs. 2 x 8GB
Trump signs AI education order to train K
The Future of Tech: Gaming Consoles, the Xbox and PlayStation of Tomorrow
The Dark Web: What is It and How To Access It
Microsoft adds 50 classic retro games to Xbox Game Pass
接受PR>=1、BR>=1,流量相当,内容相关类链接。