Pluto’s Expanding Atmosphere
By Harman Smith and Laura Generosa (nee Berwin), graphic artists and contractors to NASA's Jet Propulsion Laboratory, via Wikimedia Commons

Pluto’s Expanding Atmosphere

by on
Featured in News to Know

Pluto’s atmosphere is expanding dramatically.

News Sources

Pluto is the only dwarf planet known to have an atmosphere. Its nitrogen-methane atmosphere, previously 60 km thick, has now swelled to 3000 km (1864 miles). It also contains some carbon monoxide.

Pluto made its closest approach to the sun in 1989. Astronomers expected that its atmosphere would diminish as it cooled when Pluto gained distance from the sun. Since the opposite occurred, it is possible that other factors have caused Pluto to absorb heat more efficiently, perhaps a darkening of the surface ice. Solar energy absorbed by the dark frozen surface may be the heat source now causing the atmospheric gases to expand. Another proposed explanation for the rapid expansion is interaction with the sun’s 11-year solar cycle.

These atmospheric changes likely represent a seasonal variation, but with a 248-year orbit, Pluto’s seasons will last for decades. NASA’s New Horizons spacecraft should reach Pluto by 2015 in time to make more observations of Pluto’s atmosphere before the nitrogen gas freezes for the 120-year winter.

Pluto was considered our ninth planet until a tenth one was discovered. Hundreds of other trans-Neptunian objects (TNOs) have since been found, including a few large enough to be called dwarf planets. Pluto was reclassified as a dwarf planet in 2006 because it is much smaller than any planet and shares its region of the solar system with many other similar sized TNOs.

For More Information: Get Answers

Remember, if you see a news story that might merit some attention, let us know about it! (Note: if the story originates from the Associated Press, FOX News, MSNBC, the New York Times, or another major national media outlet, we will most likely have already heard about it.) And thanks to all of our readers who have submitted great news tips to us. If you didn’t catch all the latest News to Know, why not take a look to see what you’ve missed?

(Please note that links will take you directly to the source. Answers in Genesis is not responsible for content on the websites to which we refer. For more information, please see our Privacy Policy.)


Get the latest answers emailed to you.

I agree to the current Privacy Policy.

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Answers in Genesis is an apologetics ministry, dedicated to helping Christians defend their faith and proclaim the gospel of Jesus Christ.

Learn more

  • Customer Service 800.778.3390