(CNN) Just 11 light years from earth is the GJ 15 A star system with two planets orbiting a red-dwarf star. This makes it the closest solar system to Earth that contains multiple planets.
While you're here, how about this:
Lessons from scorching hot weirdo-planets
Illustration of a hot Jupiter planet in the Messier 67 star cluster. Hot Jupiters are so named because of their close proximity — usually just a few million miles — to their star, which drives up temperatures and can puff out the planets.
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Hot Jupiters were the first kind of exoplanet found. A quarter-century later, they still perplex and captivate — and their origins hold lessons about planet formation in general.
In 1995, after years of effort, astronomers made an announcement: They'd found the first planet circling a sun-like star outside our solar system. But that planet, 51 Pegasi b, was in a quite unexpected place — it appeared to be just around 4.8 million miles away from its home star and able to dash around the star in just over four Earth-days. Our innermost planet, Mercury, by comparison, is 28.6 million miles away from the sun at its closest approach and orbits it every 88 days.
A NASA report finds planetary contamination rules may be too strict | Science News
Some policies for protecting the moon, Mars and other places in the solar system from contamination by visiting missions may be too strict.
At least one astrobiologist cautioned, however, against relaxing current guidelines too much. Spacecraft landing in areas deemed sterile could still contaminate areas that are potentially interesting for astrobiology, says John Rummel of the SETI Institute in Mountain View, Calif. If a lunar probe crashes on the moon's surface, "you end up with material that's taken into the lunar atmosphere and deposited in the cold traps at the south and north anyway," he says. "You don't even have to land at the south pole to affect [it]."
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Astrobiologist Alberto Fairén of Cornell University welcomes the possibility of adding nuance to the "extremely restrictive" protection guidelines for Mars. He and colleagues recommended a few high-priority astrobiology zones in Advances in Space Research in March, including lakes of liquid water possibly hidden under ice sheets ( SN: 12/17/18 ).
Another Pluto? What the discovery of a new dwarf planet means to astronomy | Salon.com
Ceres, Eris, Makemake, Haumea, and Pluto are expected to have a new friend, Hygiea, inducted into our solar system’s dwarf planet club. Hygiea was long believed to be a large asteroid in the asteroid belt, but has met all the requirements needed to become a dwarf planet thanks to new observations made by Chile’s Very Large Telescope (VLT).
The findings and new images that suggest Hygiea is actually a dwarf planet were published in Nature Astronomy by astronomer Pierre Vernazza of the Laboratoire d’Astrophysique de Marseille in France and his team of researchers.
“Thanks to the unique capability of the SPHERE instrument on the VLT , which is one of the most powerful imaging systems in the world, we could resolve Hygiea’s shape, which turns out to be nearly spherical,” Vernazza said in a media statement . “Thanks to these images, Hygiea may be reclassified as a dwarf planet, so far the smallest in the Solar System.”
While you're here, how about this:
NASA Just Picked New Planetary Missions to Study. Here Are The Most Exciting Ones
Look, Mars is great. It's full of great rocks , and those blue sunsets are just top-notch. But there's no denying it: Mars definitely gets way more attention than other planets. At time of writing, there are eight active probes on or orbiting Mars.
Other Solar System planets have their secrets too, and NASA has just funded a bunch of planetary mission concept studies to see what's feasible to explore in the near future.
These studies will be published in the 2023 Planetary Science Decadal Survey, a US National Research Council publication produced every 10 years or so, identifying key issues and outlining recommendations for the coming decade in planetary science.
Not all of the concept studies will be selected to be developed into full missions; and then, not all the selected missions will end up being fully developed. A Mars mission concept from the 2013 survey, for instance, was cancelled .
What Makes a Planet and How Many Are There in Our Solar System?
What makes a space object a planet? How many are there actually in our solar system? Let's find out.
How many planets are there in our solar system? 9? 8? 12? More? The answer might actually surprise you.
Here we explore the answer to this apparently simple question and take a quick tour of the main primary planets of our home solar system.
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What is a planet? An enormous chunk of stuff (rock or gas), roughly spheroidal in shape that orbits a star and may or may not have a moon, right?
While this is in part true, there are some issues with such a simple definition. What about asteroids? When does an object become large enough to be considered a planet?
Why are Venus and Mercury planets (according to current classifications) but not Pluto? As it turns out, the reasons are pretty straight forward.
'Galaxy of Horrors!' NASA Posters Highlight Spooky Alien Planets (Video) | Space
This Halloween season, NASA wants to open your eyes to the glorious spookiness all around us in the Milky Way galaxy.
The space agency has just released two new "Galaxy of Horrors" posters, which highlight a few of the most bizarre and inhospitable alien planets that scientists have discovered. And NASA created a fun 2-minute video, styled like a trailer for a 1950s horror movie, to promote the posters.
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One of the featured worlds is HD 189733 b , a blue planet where winds whip sharp silicate-shard rain through the air at up to 5,400 mph (6,700 km/h).
"If human or robotic explorers could travel 63 light-years from Earth to get there, they would never survive this planetary hellscape," NASA officials wrote in a statement about the exotic exoplanet.
The other poster focuses on Poltergeist, Draugr and Phobetor, three planets that orbit the pulsar PSR B1257+12, which lies about 2,000 light-years from Earth. Pulsars are fast-spinning stellar corpses that emit beams of radiation from their poles; these beams appear to pulse because of the rotation, which gives pulsars their name.
To Find Baby Planets, Researchers Chase Waterfalls of Gas | Smart News |
Since researchers discovered the first exoplanets in the 1990s , astronomers have gotten pretty good at finding satellites orbiting distant suns, cataloguing 4,000 planets in more than 3,000 planetary systems since then. Now, researchers are interested in learning how these planets form, and a new technique may help them find hard-to-locate baby planets.
Young stars often have a disk of gas and dust swirling around them. Planets typically coalesce from this material, and eventually grow large enough to clear a path through these protoplanetary disks . But researchers aren’t certain that all of the gaps they’ve found actually come from young planets. That’s why a team recently looked at these disks in a new way, as they describe in a new study published in the journal Nature .
Astrophysicist Richard Teague, who conducted the study at the University of Michigan, and his team examined new high-resolution data from the Atacama Large Millimeter Array (ALMA), a radio observatory in Chile. In particular, they were able to observe the velocity of carbon monoxide gas moving within the protoplanetary disc around a young star called HD 163296. While hydrogen makes up the majority of the gas in the disk, carbon monoxide emits the brightest wavelengths, giving researchers the most detailed picture of how gas moves within the disk.
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