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Planets

An artistic rendering of the MMX spacecraft next to the potato-shaped Martian moon Phobos

Scientists Don’t Know How Mars Acquired Its Two Moons. Japan Just Launched a Historic Space Mission That Will Fetch Samples to Find Out

The Japan Aerospace Exploration Agency’s spacecraft is expected to reach the Martian system in August 2027 and return samples from the moon Phobos to Earth in 2031

This artist’s concept shows the Beta Pictoris system, about 63 light-years away.

Researchers May Have Directly Glimpsed an Exoplanet’s Magnetic Field for the First Time, Building Hope of Peering Deeper Into Faraway Worlds

Radio signals emanating from Beta Pictoris b suggest that this young and massive exoplanet has a strong magnetic field and intense auroral show

An artistic concept of the second-generation planet orbiting the white dwarf HS 0209+0832

Like a Mythical Phoenix, This Planet May Have Risen From the Ashes of a Dead Star

The “second-generation” world, predicted from telescope data, could be the first known planet of its kind, and it may shed light on the future of our own solar system

Mercury as seen by NASA’s MESSENGER spacecraft during a flyby in 2008, before it began orbiting the planet.

Mercury Has Wrinkles That Show It’s Shrinking. Now, Scientists Say the Planet Has Shriveled Far More Than Previously Thought

A new study suggests that our solar system’s smallest planet has shrunk by up to 30 percent since its birth roughly 4.5 billion years ago

An image of the crater captured by NASA’s Lunar Reconnaissance Orbiter on March 3, 2026.

The Moon Just Got a Massive New Crater That’s Wider Than Two End-to-End Football Fields. It’s a ‘Once-in-a-Lifetime Observation’

The impact crater was formed in 2024 when an object the size of a multistory building crashed into our lunar companion. The resulting divot is about 728 feet wide and 141 feet deep

Venus is one of only two planets in our solar system that lack a moon. (Mercury is the other.)

Billions of Years Ago, Venus May Have Had a Moon—Which the Planet Promptly Gobbled Up, Study Suggests

Scientists have puzzled over why the planet dubbed “Earth’s twin” doesn’t have a moon. Computer simulations hint that if Venus ever did have one, it probably would’ve cannibalized its companion

An artistic rendering of the ESA's Mercury Planetary Orbiter in the foreground and JAXA's Mercury Magnetospheric Orbiter in the background near Mercury.

After an Eight-Year Journey, Two Spacecraft Have Begun Their Arrival to Mercury, the Inner Solar System’s Most Mysterious Planet

The BepiColombo mission, by the European Space Agency and the Japan Aerospace Exploration Agency, is only the third to study our smallest planetary neighbor

Observations by amateur astronomers and imagery from the Hubble Space Telescope have revealed a ten-sided shape around Saturn’s south pole.

A Mysterious Decagon Unexpectedly Appeared Around Saturn’s South Pole. The Ten-Sided Shape Seems to Be a Wave in the Atmosphere

Decades ago, scientists found a hexagon around Saturn’s north pole. Now, recent images reveal a decagon in the planet’s southern hemisphere—and it seems to have recently formed

The new study examined Mars' gravitational field to infer its interior structure.

Mars’ Southern Half Is Weirdly Warm Underground. The ‘Thermal Anomaly’ Might Explain Why the Planet’s Hemispheres Look So Different

Researchers used a novel technique to figure out what’s going on inside the Red Planet. The work suggests that the interior of the southern hemisphere is hundreds of degrees hotter than that of the northern hemisphere and partially molten

NASA has been planning and developing the Roman Space Telescope for 16 years.

NASA’s Nancy Grace Roman Space Telescope Launches to Find Exoplanets and Unravel Mysteries of Dark Matter and Dark Energy

The new observatory will complete three surveys of the universe in five years, although it’s designed to function at least twice as long. Its data could change scientists’ basic understanding of the cosmos

A view of Pluto from NASA’s New Horizons spacecraft shows the planet’s signature heart-shaped feature.

Once the Solar System’s Ninth Planet, Pluto Was Reclassified 20 Years Ago. Here’s Why Planetary Scientists and the Public Alike Love the Small, Icy Body

Pluto is now the most well known of the outer worlds beyond Neptune—and the darling of the solar system

The Falcon 9 rocket's upper stage left its mark on the moon's surface. 

A SpaceX Rocket Part Just Slammed Into the Moon, Creating a Dust Plume and Crater. Here’s What Some Scientific Instruments Saw

The Korea Aerospace Research Institute captured before-and-after images of the impact site, and a telescope in Chile detected signs of the plume. However, no one was able to watch the collision live

A 2022 image of Neptune, captured by the James Webb Space Telescope's Near-Infrared Camera

Neptune May Have Once Witnessed a Lunar Massacre That Turned Its Original Moons ‘Inside Out’

A new study identifies an unexpected mineral in two of the planet’s inner moons, pointing to a destructive past in which a large object got pulled into the system and obliterated the former, larger satellites

Betelgeuse, the inset image in the middle, is located in the constellation Orion, on the right. New images hint at a small companion star, shown in the inset image on the left, orbiting the supergiant star.

New Images Provide the Best Evidence Yet That Supergiant Star Betelgeuse Does, Indeed, Have a Long-Theorized Stellar Companion

The research team is mostly convinced by the data, but they want to capture additional observations in 2027 to confirm what they’ve found

An artist's impression of the CD-35 2722 star system

Is This Giant Celestial Body a Moon, a Planet or Something in Between? The Strange Object Calls Astronomical Labels Into Question

The newly found object, estimated to be roughly as massive as Jupiter, orbits a brown dwarf—a “failed star”—which in turn circles a small star. For now, researchers are calling the puzzling body an “exosatellite”

An artistic rendering of LHS 1140 b and its host star, with another smaller exoplanet orbiting nearby.

Could Life Exist on This Nearby World? In a First, Astronomers Find an Atmosphere on an Earth-Like Exoplanet in the Habitable Zone

While the celestial body seems to host three features that could make a livable environment—an atmosphere, a rocky composition and a temperature that could allow liquid water to sit on the surface—researchers have not currently detected any residents

An illustration of the Beta Pictoris system features the newly discovered planet, Beta Pictoris d, at the right. Its orbit is wider than those of the two other known planets moving around its star.

Astronomers Noticed a Mysterious Spot Appearing in Telescope Images. It Turned Out to Be the Faintest Exoplanet Ever Imaged From Earth

The gas giant, called Beta Pictoris d, had been hiding in plain sight for more than a decade, until two independent teams verified its existence

Asteroid Torifune as seen by Hayabusa2 from a little more than half a mile away

New Images Reveal That This Asteroid Is Actually Two Conjoined Space Rocks. They Form a Peanut-Shaped Object Called a ‘Contact Binary’

A flyby conducted by the Japanese spacecraft Hayabusa2 uncovered the asteroid’s strange shape. Data gathered by the probe will also help defend the planet against potentially threatening space rocks

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This Giant Planet May Have Survived the Death of Its Star. The James Webb Space Telescope Just Found Its Atmosphere

New observations of WD 1856 b, a gas giant closely orbiting a white dwarf, offer a preview of what could happen to Jupiter and Saturn after the sun dies in about five billion years.

The Perseverance rover inspects a Martian rock called Cheyava Falls using its Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals (SHERLOC) instrument.

Mars Rover Spots Complex Carbon on the Red Planet, Marking Yet Another Detection of a Building Block of Life

Along with other recent discoveries, the new finding from Perseverance boosts the case that Mars once hosted conditions that could support living things—but it isn’t a definitive sign of ancient organisms

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