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Solar System

An artist's impression of the collision between the early Earth and Theia, which may have formed the moon

A Planet Slammed Into Earth 4.5 Billion Years Ago, Forming the Moon. The Projectile May Have Been Our Neighbor

Little is known about the long-destroyed moon-forming planet, Theia. But it may have been born in the inner solar system—just like Earth—a new study suggests

This image was captured by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter in October. 

More Than a Dozen NASA Spacecraft Have Glimpsed Interstellar Comet 3I/ATLAS. Now, You Can View New Images That They Captured

The space agency got a close look at the interstellar visitor over the past few months as it zipped by Mars and the sun

This glimpse of the northern lights was captured in Missouri on November 11, 2025.

The Sun Erupted With the Year’s Largest Solar Flare This Week, and Space Weather-Fueled Aurora Activity Could Continue

The last in a series of three coronal mass ejections hit Earth on Wednesday, so experts are keeping an eye on geomagnetic storm potential

A supermoon in July 2022

November’s Full Beaver Supermoon Peaks on Wednesday—and It Will Be the Year’s Biggest

Supermoons occur when full moons coincide with the moon’s closest position to Earth in its orbit

The European Space Agency’s ExoMars Trace Gas Orbiter captured images of 3I/ATLAS on October 3.

A Rare Interstellar Comet Just Flew by Mars—Here Are the Photos Captured by an Orbiting Spacecraft

The images offer the closest view yet of comet 3I/ATLAS, famous for being only the third known interstellar object to pass through our solar system

Comet C/2025 A6 (Lemmon) moves closer to the sun, as captured on October 2.

Here’s How to See Two Comets and a Meteor Shower Light Up the Sky This Month

Skywatchers are anticipating prime viewing conditions for an annual showing of shooting stars and two comet flybys

Saturn’s E ring contains grains of water ice from the underground ocean on its moon Enceladus.

Decades-Old Data From Saturn’s Moon Enceladus Hints at Favorable Conditions for Life

The Cassini spacecraft flew by the small, icy moon in 2008, collecting information that suggests it shoots out molecules that could enable life

Seismic data from marsquakes provide insight into the Red Planet's interior.

How Marsquakes Have Helped Researchers Investigate the Depths of the Red Planet’s Interior

Two recent studies used seismic data from NASA’s retired InSight mission to shed light on what lies beneath Mars’ surface and what it means for the planet’s history

The three missions launched on a SpaceX Falcon 9 rocket the morning of September 24.

‘Ultimate Cosmic Carpool’ Sends Three New Missions to Monitor Space Weather and the Protective Bubble Around Our Solar System

The spacecraft will map the boundaries of the heliosphere, study how Earth’s outer atmosphere reacts to solar activity and provide continuous monitoring of space weather

An artistic rendering depicting dozens of exoplanets

Exoplanet Discoveries Pass the 6,000 Mark, Shedding Light on How Our Solar System Compares With the Rest of the Universe

The rate of finding these distant worlds has recently increased, with astronomers scrambling to accommodate the data

Quasi-moons follow heliocentric orbits, centered around the sun, that are similar to Earth's.

Cool Finds

Astronomers Say Earth Has a Newly Discovered ‘Quasi-Moon,’ a Companion That Shares Its Orbit Around the Sun

Researchers are discussing 2025 PN7, a small celestial body that’s following a similar orbital path to our planet’s without being gravitationally tied to Earth

A coronal mass ejection erupts from the sun in 2013.

How Prepared Are We for a Rare and Powerful Solar Event?

A coronal mass ejection could knock out power and disrupt communication on Earth

Saturn will be at its brightest on September 21. 

Here’s How to See Saturn at Its Best and Brightest This Month

The giant planet will enter opposition, when the Earth will be between Saturn and the Sun, this weekend

The dwarf planet Ceres, the only dwarf planet in the main asteroid belt, might have once been hospitable for life, according to a recent study.

Did the Dwarf Planet Ceres Once Host Life? Astronomers Suggest Chemical Energy Could Have Fueled Microbes Long Ago

Though no direct evidence of life has been found, models suggest Ceres had hot water shooting into its underground oceans billions of years ago, offering potentially hospitable conditions

A solar flare with the Earth for scale.

Solar Flares May Be Way Hotter Than Researchers Previously Thought

Scientists recalculated the temperature of solar flares using modern data and new models

The Hubble Space Telescope captured this image of 3I/ATLAS with its Wide Field Camera 3.

Telescopes Reveal Surprising Chemistry of a Rare Interstellar Object Passing Through Our Solar System

Called 3I/ATLAS, the object is only the third of its kind known to astronomers, and it’s likely been heading our way for billions of years, carrying pristine material from another star system

New moons are only visible during solar eclipses. This visualization of a tiny sliver, for example, is technically a crescent moon.

What Is a Black Moon? The Unusual Sky Phenomenon Will Occur Later This Month, but Don’t Expect to See It

A seasonal black moon, to appear on August 22 or 23, is the third of four new moons within an astronomical season

The trans-Neptunian object nicknamed Ammonite moves across the sky over several hours in May 2023. Its diameter is estimated to be between about 135 and 235 miles.

Cool Finds

Astronomers Discover ‘Ammonite,’ a Mysterious Distant Object That Could Shed Light on Our Solar System’s History

The celestial body’s unusual orbit “implies that something extraordinary occurred” in the early days of the solar system—and throws a wrench in the Planet Nine idea

An image from the ALMA telescope array in Chile shows jets of silicon monoxide blowing away from the young star HOPS-315. The blue jet is moving towards Earth, and the red jet is moving away from us.

For the First Time, Astronomers Capture ‘Smoking Gun’ of Early Solar System Formation

Telescopes detected the first stages of hot minerals condensing from gas around a young star called HOPS-315

The meteorites could open up a new avenue to understand Mercury, pictured, which is notoriously hard to study due to its proximity to the sun.

Scientists Have Never Confirmed a Meteorite From Mercury. Could These Space Rocks From the Desert Be the First?

Two meteorites found in the Sahara show tantalizing similarities to the innermost planet, and while researchers say they are likely not direct samples, “one cannot rule out” the idea

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