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comets

What Is a Comet?
Image: iStockphoto.com/PaulFleet

What Is a Comet?

Comets are more than brilliant streaks of light in the night sky. These icy objects orbiting the Sun are actually fossils, rocky remnants from the early days of our solar system.

Discover how the comet’s coma and tail are formed and why Sun-grazing comets are important to astrophysics.

NASA
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Rosetta Mission: Can You Land on a Comet?

Rosetta Mission: Can You Land on a Comet?

Landing a spacecraft on a spinning comet — that's what the European Space Agency's ambitious Rosetta Mission is trying to do. Play along with this game. More...

Game
BBC
Quest for a Comet

Quest for a Comet

Comets are a huge source of the interplanetary dust that scatters light and creates zodiacal light and gegenschein. In this game, you’ll join the robotic Rosetta mission to land on and study a comet. More...

Game
NASA
Make Your Own Comet

Make Your Own Comet

Create a "dirty snowball" with water, potting soil, ammonia, dry ice, and a few other common items. Then hold it up to a lamp in a darkened room to see the smoking comet tail of melting gases.
More...

Activity
Penn State
Rosetta Mission Lander Set to Explore Surface of Comet

Rosetta Mission Lander Set to Explore Surface of Comet

While the world watched, the Rosetta team navigated a minifridge-size lander onto a spinning comet. Discover how the Philae robotic probe is "set to dig into 67P's frozen secrets." More...

Article
Science News for Students
Comet Siding Spring: Duck and Cover!

Comet Siding Spring: Duck and Cover!

What will happen to the Mars orbiters when a comet just misses the planet on October 14, 2014? Hopefully nothing bad! See how NASA is preparing. More...

Article
NASA
What If an Asteroid or Comet Hits My Town?

What If an Asteroid or Comet Hits My Town?

If you've ever wondered what the answer to that question is, then you should definitely give this a try. Go ahead. Drop a rock on someone! More...

Interactive
Space Science Institute
Comet ISON Interview

Comet ISON Interview

Dr. Alex Young from NASA’s Goddard Space Flight Center talks about comet ISON’s once-in-a-lifetime journey. A Sun-grazing comet, it passed very close to the solar surface. More...

Video
NASA
Comets 101

Comets 101

Comets consist of a nucleus, a coma, and two kinds of tails. Most spend their time on the outskirts of the solar system, then zoom in for a pass by the Sun. More...

Article
NOVA/PBS
Comets: Earth Impact

Comets: Earth Impact

In theory, if a chunk of comet just 300 meters across crashed into Earth, it could change the climate and produce enough dust to block out the sun. Take a look. More...

Video
Science Channel
Educator’s Guide to Kitchen Comets

Educator’s Guide to Kitchen Comets

Want to make your own model of a comet nucleus? Follow this recipe using dry ice, water, ammonia, dirt, and corn starch. More...

Activity
NOVA/PBS
Solar Dynamics Observatory

Solar Dynamics Observatory

Check out these videos, which explain why studying Sun-grazing comets, like Lovejoy, helps us learn about the Sun’s turbulent atmosphere, magnetic field, and the corona. More...

Video
NASA
Ask a Scientist: Speed of Comets

Ask a Scientist: Speed of Comets

NASA scientist Steve Chesley answers a great question about comets: How do they gain speed as they move along through space? Hint: The Sun's gravity has a lot to do with it. More...

Video
NASA/JPL
Asteroids and Comets

Asteroids and Comets

Asteroids and comets are rocky remnants from the solar system's creation 4.5 billion years ago. Explore notable asteroids and comets — and the difference between these two kinds of cosmic rocks. More...

Article
National Geographic
Comet ISON

Comet ISON

An international campaign of scientists has been tracking the comet ISON’s perilous journey around the Sun. Watch videos, check out images and infographics, and learn the fate of ISON. More...

Article
NASA
How to Cook a Comet

How to Cook a Comet

See what happens when you cook a comet in the Sun’s radiation. As it heats, the outer layer turns into gas — a process called sublimation. More...

Video
NASA
Impacts on Jupiter

Impacts on Jupiter

Because of its mass, Jupiter’s gravity pulls in more comets and asteroids than any other planet. See what researchers are learning about these collisions — and how their studies can impact Earth. More...

Video
National Science Foundation
Interactive Comet Animation

Interactive Comet Animation

This interactive animation shows the Churyumov-Gerasimenko comet’s orbit around the Sun. See what happens when you change the orbit’s size or eccentricity (how oval-shaped the orbit is). More...

Interactive
Windows to the Universe
PacSci-Doku: Cosmic Landing

PacSci-Doku: Cosmic Landing

What's 2.8 miles long, 2.1 miles wide, and 300 million miles away? Solve this Sudoku-inspired puzzle to get the answer. More...

Game
Pacific Science Center
Photos: Comet Pan-STARRS Debuts in Southern Hemisphere

Photos: Comet Pan-STARRS Debuts in Southern Hemisphere

Astrophotographers around the world snapped photos of the comet Pan-STARRS as it fell toward the Sun in March 2013. Check out the comet’s bright coma and tail. More...

Images
National Geographic
Solar System Exploration: Comets Gallery

Solar System Exploration: Comets Gallery

See photos of comets soaring through space, including Hale-Bopp, Lovejoy, ISON, and 109P/Swift-Tuttle, which visits the inner solar system every 133 years.
More...

Images
NASA
Studying Comet Contents

Studying Comet Contents

NASA’s Stardust Mission captured dust from the comet Wild-2. The dust contained an amino acid, a building block of life. What does this mean? Listen as astronomer Don Brownlee explains. More...

Profile
NPR/Science Friday

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