Solar System

An artist's conception of four of the new planets, orbiting a single dwarf star. These small, rocky worlds are far closer to their star than Mercury is to our sun, but the star is smaller and cooler than our own.

Kepler Just Found 104 New Planets Outside of Our Solar System

Is anyone home?

Galaxy GN-z11 seen in its youth by the Hubble telescope. GN-z11 is shown as it existed 13.4 billion years in the past, just 400 million years after the Big Bang.

If Telescopes Are Time Machines, the JWST Will Take Us the Furthest Back Yet

The James Webb Space Telescope promises to peer back into the making of the first galaxies

A view of twilight on Pluto

New Evidence Strengthens the Case for Pluto's Underground Ocean

Features on the dwarf planet's smooth surface suggest that not all is frozen on that tiny, distant world

An artists' conception of a dust storm on Mars. New research may explain why the truly massive dust storms seem to occur irregularly on the Red Planet.

Mars Weather Forecast Calls for Massive Dust Storms -- Here's Why

Planetary-wide dust storms on Mars, lasting for months, may be linked to the motion of the Red Planet around the solar system.

Mercury’s northern volcanic plains shown in enhanced color to emphasize rocks types. The bottom left portion of the image displays large wrinkle ridges, formed during lava cooling. Near the top of the image, a bright orange region shows the location of a volcanic vent.

See Mercury's Landscape in Stunning Detail

A new map of the planet's surface captures the depths of craters and the peaks of volcanic mountains

An illustration of the path Mercury will take across the sun on  May 9.

For The First Time in a Decade, Watch Mercury Cross the Sun's Face

Next week's transit of Mercury is one of the major astronomical events of the year

The Hale Crater on Mars, one area where slope lineae occur

Boiling Water Could Explain Mysterious Dark Streaks on Mars

Researchers simulate some of the Red Planet's unique features in an Earth-bound chamber

This artist's concept shows the distant dwarf planet Makemake and its newly discovered moon. Makemake and its moon, nicknamed MK 2, are more than 50 times farther away than Earth is from the sun.

Hubble Spies a Tiny Moon Orbiting Dwarf Planet Makemake

Our solar system still has plenty of surprises

Avalanches may have triggered the jets of material spewing from Comet Hartley 2.

Avalanches on Comets May Help Make the Icy Bodies Visible

Tumbling rocks may have lit up Comet Hartley 2, allowing its discovery in 1986

The bright spots of Occator Crater are shown in enhanced color in this view from NASA's Dawn spacecraft.

New NASA Images Shed Light on Ceres’ Bright Spots

Yet the dwarf planet serves up fresh mysteries

Five New Things We Learned About Pluto This Week

A new set of studies paints Pluto as a weirder planet than scientists once thought

An artist's rendering of the sweltering surface of Venus.

A Giant Planetary Smashup May Have Turned Venus Hot and Hellish

A collision with a large object may have triggered changes deep inside the planet that ultimately affected its atmosphere

Happy Leap Day! Brought to You by Julius Caesar

The leap year has a long history, stretching all the way back to 46 B.C.E.

Pluto’s North Pole Is Streaked With Canyons

Enormous pits and frozen valleys straddle Pluto’s northern hemisphere

An artist's rendering of Planet Nine, looking back toward the Sun. This depiction is of a gaseous planet, like Uranus and Neptune, with lightning brightening the clouds on the dark side.

Evidence Stacks Up for a Planet Beyond Pluto

A new paper provides the strongest evidence yet for a real Planet X

The five planets will be visible to the naked eye, but a telescope can add another layer of delight

Don't Miss This Month's Rare Planetary Alignment

Five planets will appear together in the sky—all visible to the naked eye

The back shell of NASA’s InSight spacecraft being lowered onto the lander, last July, in preparation for the mission.

Here's Why NASA Had to Postpone a 2016 Mission to Mars

A leak in a key instrument on board the InSight lander means the team will have to wait for the next launch window in 2018

Left: Alan Stern holds a 2005 Hubble image of the Pluto system on January 19, 2006, two hours after the successful launch of the New Horizons probe. Right: A triumphant Stern holds a full-frame image of Pluto, taken just hours before the New Horizons probe reached its closest point to Pluto.

How Alan Stern Brought Pluto to Earth

The scientist behind NASA's New Horizons mission gave cheering earthlings their first close-up view of the dwarf planet

This composite image features Pluto and its largest moon Charon in enhanced color.

Sorry Pluto, You Still Aren’t a Planet

A new test for planetary status leaves the diminutive world and its dwarf planet kin out of the family portrait

An artist's rendering of the MOA-2011-BLG-262 system, which hosts a potential exomoon orbiting a Jupiter-like planet.

In a Rare Pairing, a Venus-Like Planet Has Been Found Around a "Failed Star"

The system offers clues to the way planets and moons form and may aid in the quest to find habitable worlds across the galaxy

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