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Planets

Illustration of a time sequence as the celestial body moves in front of a distant star

This Tiny Celestial Body Past Pluto Shouldn’t Have an Atmosphere—but Astronomers Say They May Have Detected One

Worlds this small and distant are thought to be too cold and have too little surface gravity to hold onto gases. But the findings suggest that icy, rocky objects in the solar system’s outer reaches are more dynamic than we thought

Pluto was considered the solar system's ninth planet for more than 70 years.

Could Pluto Once Again Be Considered a Planet? New Remarks From NASA’s Administrator Highlight an Enduring Debate Among Scientists

Two decades ago, the International Astronomical Union—which defines and names celestial bodies—redefined the criteria for being a planet, putting Pluto into the new category of dwarf planet

Tatooine is a fictional desert planet with two suns. No such planet had been found when this scene in Star Wars: Episode IV–A New Hope ​​​​​​was created.

Astronomers Discover 27 Potential Planets Each Orbiting Two Stars, Just Like the Fictional Tatooine in ‘Star Wars’

The findings could more than double our current database of worlds that loop around binary star systems. But researchers need to analyze more data before they can officially celebrate a new trove of far, far away exoplanets

Comet 3I/ATLAS has much more "heavy" water than comets that formed in the solar system, according to a new study.

Interstellar Comet 3I/ATLAS Came From an Extremely Cold, Lonely Region of the Milky Way Galaxy, New Research Suggests

Astronomers analyzed the vapors coming off the comet when it neared the sun and found it had a lot of “heavy” water. That hints it grew up in a frigid planetary system, possibly before its home star formed

After drilling a rock sample from a spot on Mars nicknamed “Mary Anning,” NASA’s Curiosity rover took this selfie on October 25, 2020. Now, that sample has revealed organic molecules that have never been seen on the red planet before.

A Mars Rover Found Building Blocks of Life Never Seen on the Red Planet Before, Boosting the Case for Ancient Habitability

The organic molecules discovered by NASA’s Curiosity rover could have been formed by life, but they could have also come from geologic processes or meteorites

Artemis 2's Orion capsule splashed down in the Pacific Ocean off the coast of San Diego.

Artemis 2 Astronauts Successfully Return to Earth After Completing a Historic Mission Around the Moon

The crewmembers splashed down Friday after breaking a space-faring record and viewing lunar features never seen by human eyes during their ten-day trip. It marks the first time anyone has left Earth’s orbit in more than 50 years

A violent, swirling storm on Jupiter captured by NASA's Juno spacecraft

Lightning Strikes on Jupiter Are 100 Times as Powerful as Those on Earth, a New Study Suggests

Scientists finally have a clearer picture of the gas giant’s intense storms

The researchers collected samples from the Pilbara region in Western Australia.

When Did the Earth’s Crust Start to Shift? Scientists Uncover Evidence of Plate Tectonics Happening 3.48 Billion Years Ago

A new study provides the oldest direct evidence of tectonic plate movement ever recorded

Illustration of L98-59d (lower left) orbiting its host star, a red dwarf

Scientists May Have Discovered a New Type of Planet Beyond the Solar System. The Catch? It Smells Like Rotten Eggs

L98-59d seems to be a molten planet with an atmosphere full of hydrogen sulfide

The researchers used sound waves to levitate tiny glass spheres as part of their study. 

Scientists Make a Major Breakthrough in Solving a Hair-Raising Mystery About Static Electricity

The findings can help explain the physics behind phenomena like volcanic lightning

An artist’s illustration of the exoplanet HD 219134 b, a rocky world about 21 light-years from Earth. This scorching planet, which orbits extremely close to its host star, might have a partially molten surface and volcanoes.

Alien Life Could Look Nothing Like What We Expect. Here’s How Microbes Beyond Earth Might Live Without Liquid Water

Like the lead character of “Project Hail Mary,” some scientists are proposing ways that life might exist beyond a star’s “habitable zone,” often considered the gold standard of potential livability

Dimorphos, on the lower right, surrounded by debris moments after DART's collision in September 2022. The asteroid's larger companion, Didymos, is on the left. 

NASA’s Asteroid-Smashing DART Mission Changed a Space Rock’s Orbit Around the Sun, Marking a First for Humanity

Studying the 2022 collision’s effects can help scientists protect the Earth from celestial objects that might head toward us

New images of Uranus show the planet in blue, the upper atmosphere in red, auroras in lighter red spots and rings in white.

Take a Look at Uranus’ Weird, Lopsided Upper Atmosphere Bespeckled with Auroras

A new 3D map of gas surrounding the planet will help researchers better understand the strange world

Saturn's rings are surprisingly young

A Smashing New Proposal About Saturn’s History Might Explain Its Iconic Rings and Some of Its Odd Moons

A crash involving the planet’s largest moon, Titan, and a hypothetical moon may have triggered a curious sequence of events

An artistic rendering of the 'inside out' solar system

Astronomers Discover an Exoplanet in the Wrong Place, Hinting at a Planetary System That Was Born ‘Inside Out’

A rocky planet was found orbiting its host star in an unusual location

Earth's core is mostly made of the metals iron and nickel, but it also contains lighter elements like hydrogen, oxygen and silicon. 

Earth’s Core Might Hold Dozens of Oceans Worth of Hydrogen, Hinting at the Origins of the Planet’s Vast Water Supply

Scientists have long debated whether most of Earth’s vital liquid was delivered via icy comets or was homemade

The updated measurements won't take away Jupiter's status as the solar system's biggest planet.

Scientists Say That Jupiter—the Solar System’s Largest Planet—Might Be Slightly Smaller Than Previously Thought

Updated measurements from NASA’s Juno spacecraft could help researchers better understand the planet’s mysterious interior, as well as other gas giants

An artistic illustration of the MAVEN orbiter and Mars

NASA to Resume Search for Missing Mars Orbiter, but Prospects of Re-establishing Communication With It Seem Slim

Scientists haven’t heard from the MAVEN orbiter since December 6. It had been studying the Martian atmosphere for over a decade

A supermoon rises over Washington, D.C., on December 3, 2017.

The Year’s First Bright Supermoon and the Colorful Quadrantid Meteor Shower Coincide This Weekend

The dual celestial events will ring in the new year, although the luminous “wolf” supermoon may hamper skywatchers’ view of the shooting stars

Look up throughout the year to catch a wide array of astronomical sights.

Don’t Miss These Ten Celestial Events in 2026, From Aligned Planets to a Total Solar Eclipse

The upcoming year will offer a blood-red moon, spectacular meteor showers and the first glimpse of the sun’s corona since April 2024

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