Comets

Comets are remnants from the early days of the solar system, billions of years ago. Primarily made of ice and dust, these "dirty snowballs" orbit the sun and in habit the Oort cloud, an area in the outskirts of the solar system beyond Pluto. As comets approach the inner solar system, solar wind from the sun can sweep dust back into a long tail. When these comets are close enough to Earth, they can appear as dazzling objects in the night sky. Space probes from Earth have visited several comets to learn more about their composition. Learn more about comets, icy wanderers in the solar system.

Related Topics: Asteroids, Meteors, Shooting Stars and Fireballs, Rosetta Spacecraft, Stargazer Photos 

Latest Updates

After the sudden outburst in 2007, the coma of comet 17/P Holmes became temporarily wider than the sun.

Skywatchers can see debris from spectacular comet outburst this month

By Tereza Pultarova published

Debris produced by the most spectacular comet outburst ever observed will be visible from Earth later this month even to amateur telescopes. Here is how to look for it.

A bright meteor can be seen in the night sky above a harbor in Sydney, Australia.

Meteor brightens up the sky above Sydney as peak meteor showers arrive

By Tereza Pultarova published

The peak shooting star season has arrived with six meteor showers expected to pepper Earth in the upcoming weeks as the planet hurtles through fields of cometary debris.

star streaks and a blurry comet

Goodbye, Comet K2! Next stop: closest approach to the sun

By Elizabeth Howell published

Mysterious comet K2 made its closest approach to Earth yesterday and is continuing its journey toward the sun.

star streaks and a blurry comet

A huge comet makes its closest approach to Earth today. Here's how to watch it live.

By Samantha Mathewson published

One of the farthest active comets ever spotted will makes closest approach to Earth on July 14, and here's how you can catch the action live.

An image of comet C/2017 K2 PANSTARRS (K2) taken in June 2017 by the Hubble Space Telescope's Wide Field Camera 3.

The massive, strange Comet K2 is touring the solar system, surprising scientists as it goes

By Tereza Pultarova published

K2, the most pristine comet ever observed, makes a visit to Earth this week. Here is what scientists have learned about it since its surprising discovery.

a comet

Why is Comet K2 so hard to see given its huge size?

By Elizabeth Howell published

As a huge comet makes its closest approach to Earth on July 13, you might be curious why it's so hard to spot.

a comet

What time will the huge comet K2 make its closest approach to Earth?

By Elizabeth Howell published

Comet C/2017 K2 (PANSTARRS), called K2 for short, is one of the farthest active comets ever spotted and will whizz by our planet on July 13.

Comet C/2017 K2 PANSTARRS was captured on June 18, 2022 in constellation Ophiuchus, at magnitude 9.7.

Megacomet K2 caught on camera cruising through celestial equator

By Elizabeth Howell published

A megacomet glows in the dark in this long-exposure image captured by an astrophotographer on June 18, before its closest approach to Earth.

comet hale-bopp

James Webb Space Telescope has comets to catch when science begins

By Stefanie Waldek published

The James Webb Space Telescope's powerful infrared instruments will be trained on three types of comets, potentially providing insight into the solar system's early life.

An image of comet C/2017 K2 PANSTARRS (K2) taken in June 2017 by the Hubble Space Telescope's Wide Field Camera 3.

A huge comet will fly by Earth in July and you might be able to see it

By Elizabeth Howell published

A comet first spotted in the distance in 2017 might finally be within view soon of amateur astronomers.

On the left, comet 323P/SOHO observed by the Subaru Telescope in December 2020. On the right, an image of the comet taken in February by the Canada-France Telescope.

Telescopes watch the sun bake a comet to death

By Tereza Pultarova published

Telescopes watch as a comet disintegrates near the sun, gathering data that might help explain why some comets seem to disappear.

The Comet Interceptor mission will wait in the Lagrange Point 2 for a pristine yet unknown comet to arrive.

Europe will launch a 'lurking' probe in 2029 to watch for an interstellar comet

By Tereza Pultarova published

Europe's Comet Interceptor probe will lurk in space, waiting for a pristine interstellar comet to zoom by.

The dramatic outburst of Comet 17P/Holmes, seen in October 2007.

Watch the biggest-ever comet outburst spray dust across the cosmos

By Stephanie Pappas published

The dust trail from the largest comet outburst on record will be visible to amateur astronomers in late July 2022.

A tau Herculids meteor streaks above sandstone formations at the Valley of Fire State Park, Nevada on May 30, 2022. The shooting star came from the shards of comet 73P/Schwassmann-Wachmann, or SW3.

New tau Herculid meteor shower drops bright fireballs, but no 'meteor storm,' for stargazers (photos)

By Elizabeth Howell published

"Shooting stars" from a new meteor shower lit up the night sky in a dazzling display, even if it wasn't a "meteor storm" some stargazers hoped for.

Artist's illustration of a meteor shower.

Possible early tau Herculid meteors caught on camera

By Elizabeth Howell published

Reports are coming in from observers who caught a few early shooting stars.

Artist's illustration of a meteor shower.

Want to see the potential tau Herculids meteor shower? Here's what to expect, according to NASA.

By Elizabeth Howell published

If you're hoping to see the potential tau Herculids meteor shower, NASA advises you to check the weather and be ready for the unexpected.

Artist's illustration of a meteor shower.

Possible outburst of tau Herculids meteors tonight!

By Elizabeth Howell last updated

A potential meteor shower may emerge from Hercules tonight (May 31-31). Keep your eyes peeled and your fingers crossed.

These star trails are from the Eta Aquarids meteor shower of 2020.

A 'meteor storm' of 1,000 shooting stars per hour may light up the skies over North America this week

By Elizabeth Howell last updated

A painting of the Leonid meteor storm of 1833 over the Niagra Falls by Edmund Weiß in 1888.

Fragments of a dying comet might put on a spectacular show — or pass by without a trace

By Jonti Horner, Tanya Hill last updated

Occasionally, Earth runs through a particularly narrow, dense clump of debris, resulting in a meteor storm.

Astrophotographer Sean Parker produced this image of Quandrantid meteors over Tucson, Arizona on Jan. 3, 2013.

A potential new meteor shower from shattered comet has scientists excited

By Rahul Rao last updated

This weekend, Earthlings might be treated to the sight of a new meteor shower. Astronomers certainly hope it happens.