Penn State has hand in discovery of most Earth-like planet yet
Astronomers have discovered what they say is the most Earth-like planet yet detected — a distant, rocky world that's similar in size and exists in the “Goldilocks” zone where it's not too hot and not too cold.
The team includes Penn State scientists using data from NASA's Kepler Space Telescope, which examines the heavens for subtle changes in brightness that indicate an orbiting planet is crossing in front of a star. From those changes, scientists can calculate a planet's size and make certain inferences about its makeup.
Researchers have collected data about more than 3,900 possible planets, but of the 961 they've confirmed, all but this newfound object are at least 40 percent larger than Earth, Penn State professor of astronomy and astrophysics Eric Ford said.
Ford, who co-authored a paper in the journal Science announcing the find, said the planet, dubbed Kepler-186f, circles a red dwarf star 500 light years from Earth in the constellation Cygnus. A light year is nearly 6 trillion miles.
The planet is about 10 percent larger than Earth and may have liquid water on its surface, scientists said. Its star is much cooler than Earth's sun and emits most of its radiation as infrared light rather than visible light.
Questions linger about the planet's atmosphere, surface temperature and possible life forms, Ford said.
The planet probably basks in an orange-red glow from its star and is likely cooler than Earth, with an average temperature slightly above freezing, “similar to dawn or dusk on a spring day,” said University of California, Berkeley astronomer Geoff Marcy, who had no role in the discovery.
Lead researcher Elisa Quintana at NASA's Ames Research Center said she considers the planet to be more of an “Earth cousin” than a twin because it circles a star that is smaller and dimmer than Earth's sun. While Earth revolves around the sun in 365 days, this planet completes an orbit of its star every 130 days.
Kepler-186f is part of a system of five planets, all of which are about Earth's size. The other planets are too close to their star to support life.
The planet is too far away for further exploration, even for next-generation space telescopes.
The Associated Press contributed. Megan Harris is a staff writer for Trib Total Media. Reach her at 412-388-5815 or email@example.com.
Add Megan Harris to your Google+ circles.
Show commenting policy
TribLive commenting policy
You are solely responsible for your comments and by using TribLive.com you agree to our Terms of Service.
We moderate comments. Our goal is to provide substantive commentary for a general readership. By screening submissions, we provide a space where readers can share intelligent and informed commentary that enhances the quality of our news and information.
While most comments will be posted if they are on-topic and not abusive, moderating decisions are subjective. We will make them as carefully and consistently as we can. Because of the volume of reader comments, we cannot review individual moderation decisions with readers.
We value thoughtful comments representing a range of views that make their point quickly and politely. We make an effort to protect discussions from repeated comments either by the same reader or different readers.
We follow the same standards for taste as the daily newspaper. A few things we won't tolerate: personal attacks, obscenity, vulgarity, profanity (including expletives and letters followed by dashes), commercial promotion, impersonations, incoherence, proselytizing and SHOUTING. Don't include URLs to Web sites.
We do not edit comments. They are either approved or deleted. We reserve the right to edit a comment that is quoted or excerpted in an article. In this case, we may fix spelling and punctuation.
We welcome strong opinions and criticism of our work, but we don't want comments to become bogged down with discussions of our policies and we will moderate accordingly.
We appreciate it when readers and people quoted in articles or blog posts point out errors of fact or emphasis and will investigate all assertions. But these suggestions should be sent via e-mail. To avoid distracting other readers, we won't publish comments that suggest a correction. Instead, corrections will be made in a blog post or in an article.
- Script is it: Classic Pitt helmet design to return
- Steelers notebook: Shazier returns just in time
- Penguins notebook: Carcillo has no hard feelings after failing to make roster
- Zappala impersonator arrested; stores offered reimbursement
- Fire at Dollar General in Rostraver under control, dispatchers say
- Running against Obama
- Line painting on I-79 set for weekend
- News Alert
- America’s manufacturing comeback
- NFL notebook: Colts WR Wayne out for Sunday’s game at Steelers
- An Obama clone