Asteroids

Asteroids are space rocks thought to be the remains left over from the formation of the solar system. They range in size from tiny (the size of a car or so) to truly giant, with at least one - Ceres - gaining dwarf planet status. In our solar system, billions of asteroids are in the asteroid belt, a region around the sun between the orbits of Mars and Jupiter. Others stray from this region, and can potentially post an impact threat to the Earth. At least one interstellar asteroid, called 'Oumuamua, has passed through our solar system. Learn more about asteroids here.

Related Topics: Comets, Meteors, Shooting Stars and Fireballs, Rosetta Spacecraft 

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An artist's depiction of the OSIRIS-REx spacecraft collecting a sample from asteroid Bennu.

OSIRIS-REx asteroid samples will land on Earth in 2023 and scientists can't wait

By Briley Lewis published

In just under a year, on Sept. 24, 2023, the OSIRIS-REx sample collector — a basket full of asteroid dust and rocks — will return to Earth's surface.

An illustration of the Christmas asteroid as it approaches Earth this December offering amateur astronomers the chance to spot it.

The Christmas asteroid challenge starts tonight. Here's how to join in

By Robert Lea published

The European Space Agency (ESA) issued a challenge to spot the Christmas asteroid and encouraged anyone who does so to share their observation on social media.

The Christmas asteroid, 2015 RN35, poses no threat, but like many middle-sized space rocks out there, we just don’t know that much about it.

Amateur astronomers challenged to spot an asteroid for Christmas

By Robert Lea published

On Thursday (Dec. 15), an asteroid that could be as large as the Great Pyramid of Giza will pass Earth. Amateur astronomers are challenged to spot the asteroid.

An artist's depiction of the NEO Surveyor spacecraft searching for asteroids.

NASA green-lights asteroid-hunting space telescope for 2028 launch

By Andrew Jones published

NASA is moving ahead with the development of a spacecraft to hunt for potentially hazardous asteroids and aims to launch by June 2028.

An artist's depiction of a near-Earth asteroid.

China will launch 2-in-1 asteroid deflection mission in 2025

By Andrew Jones published

China is now looking to launch its first planetary defense test mission a year earlier than planned and on a larger rocket.

An illustration of NASA's asteroid-visiting Lucy spacecraft as it swings past Earth for a gravity assist, with one solar array not fully deployed.

NASA's Lucy asteroid-scouting mission resumes work on solar arrays in deep space

By Andrew Jones published

The team behind NASA's Lucy asteroid mission is resuming work with the spacecraft to fully deploy and latch its second solar array after a recent successful Earth flyby.

A view from NASA's Mars Reconnaissance Orbiter of a crater on Mars that formed in 2012.

Megatsunami swept over Mars after massive asteroid hit the Red Planet

By Charles Q. Choi published

A Martian megatsunami may have raced across the Red Planet after a cosmic impact similar to the one that likely ended Earth's age of dinosaurs, a new study finds.

A bright streak of light caused by a meteor passing above north-eastern U.S.

Hundreds report seeing a bright fireball in northeastern U.S.

By Tereza Pultarova published

Less than two weeks after a bright fireball lit up the sky above the Great Lakes, another spectacular meteor impressed skywatchers in the Northeast.

An artist's depiction of the twin Janus spacecraft.

NASA asteroid smallsats stranded by Psyche delay

By Andrew Jones published

NASA has removed the twin Janus smallsats from the Psyche asteroid mission after launch delays meant Janus would not be able to meet its science goals.

a large silver diamond shape with a beam connecting it to a rock, all against a starry background

NASA's Artemis 1 launched a solar sail cubesat to an asteroid. It may be in trouble.

By Meghan Bartels published

A tiny asteroid explorer that launched on NASA's moon mission last week still hasn't phoned home.

An artist's impression of an ancient Mars rich in water.

Mars' water may have come from ancient asteroid impacts

By Keith Cooper published

Isotopic evidence points to carbonaceous chondrite asteroids bringing enough water to Mars that it could have formed a global ocean some 1,000 feet deep.

A timelapse image of a fireball event over Canada on Nov. 19 from start to finish.

Astronomers spot small space rock just hours before it drops meteorites over Canada

By Tereza Pultarova published

A small space rock was discovered on Saturday (Nov. 19) just a few hours before hitting Earth's atmosphere and landing in Canada's Lake Ontario.

An illustration of an asteroid approaching Earth.

Mystery crater potentially caused by relative of dinosaur-killing asteroid

By Uisdean Nicholson, Sean Gulick, Veronica Bray published

The surprise crater was discovered on Earth's unexplored ocean floor.

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The top space stories of the week!

By Doris Elin Urrutia last updated

These are some of this week's top stories.

an image showing liftoff of osiris rex from asteroid bennu with gray boulders in behind the spacecraft

OSIRIS-REx: NASA's asteroid study and sample return mission

By Nola Taylor Tillman published

Reference NASA's OSIRIS-REx mission will drop off pieces of asteroid Bennu, a carbon-rich rock from our early solar system, in 2023. The spacecraft will then study asteroid Apophis in 2029.

Artist’s impression of the asteroid discovered toward the Sun.

Astronomers have detected another 'planet killer' asteroid. Could we miss one coming our way?

By Steven Tingay published

If you surfed the web this morning, you may have seen news of the latest existential threat to humanity: a “planet killer” asteroid named 2022 AP7.

Artist's illustration showing NASA's Psyche probe approaching its asteroid namesake.

Problems with NASA asteroid mission Psyche delay Venus probe's launch to 2031

By Elizabeth Howell published

A NASA Venus mission will have to wait at least three more years to launch due to issues with the agency's Psyche asteroid probe.

Most asteroids miss Earth at a safe distance.

Confirmed! A 2014 meteor is Earth's 1st known interstellar visitor

By Tereza Pultarova published

Astronomers have confirmed that a suspicious space rock that hit Earth in 2014 came from another star system, predating the famous interstellar visitor 'Oumuamua by three years.

streaking stars with an arrow in the middle that shows a small dot in the middle

Massive 'potentially hazardous' asteroid spotted before safe flyby of Earth today (Nov. 1)

By Elizabeth Howell published

A skyscraper-size asteroid will make a safe flyby our our planet today (Nov. 1) and it showed up on camera with the Virtual Telescope Project ahead of a live broadcast.

This aerial view shows a hole in the dish panels of the Arecibo Observatory in Arecibo, Puerto Rico, on Nov. 19, 2020.

Collapsed Arecibo Observatory reveals final 'treasure trove' to defend Earth from asteroids

By Andrew Jones published

The study is the largest ever on radar observations of near-Earth asteroids.