Featured Research

from universities, journals, and other organizations

Diamond planets may be more common than astronomers thought

Date:
May 27, 2014
Source:
Yale University
Summary:
Carbon-rich planets may be more common than previously thought, according to new research. Some of these planets, all located far beyond Earth's solar system, could contain vast deposits of graphite or diamonds, and their apparent abundance prompts new questions about the implications of carbon-intense environments for climate, plate tectonics, and other geological processes, as well as for life.

Diamond planets may be more common than astronomers thought.
Credit: Illustration by Haven Giguere

Carbon-rich planets may be more common than previously thought, according to new research by Yale University astronomers.

Some of these planets, all located far beyond Earth's solar system, could contain vast deposits of graphite or diamonds, and their apparent abundance prompts new questions about the implications of carbon-intense environments for climate, plate tectonics, and other geological processes, as well as for life.

"Despite the relatively small amount of carbon on Earth, carbon has been critical for the emergence of life and the regulation of our climate through the carbon-silicate cycle," said Yale doctoral candidate John Moriarty, who led the research, recently published in Astrophysical Journal. "It's an open question as to how carbon-rich chemistry will affect the habitability of exoplanets. We hope our findings will spark interest in research to help answer these questions."

Moriarty collaborated with Yale astronomy professor Debra Fischer and Nikku Madhusudhan, a former Yale postdoctoral researcher now at Cambridge University.

Exoplanets are planets outside Earth's solar system. In October 2012 Madhusudhan published a paper arguing that 55 Cancri e, a rocky exoplanet twice Earth's size, is likely covered in graphite and diamond.

Astronomers generally believe that rocky exoplanets are composed -- as Earth is -- largely of iron, oxygen, magnesium, and silicon, with only a small fraction of carbon. In contrast, carbon-rich planets could have between a small percentage and three-quarters of their mass in carbon. (Earth has 0.005%.)

Moriarty, Madhusudhan, and Fischer developed an advanced model for estimating exoplanet composition. Previous models were based on static snapshots of the gaseous pools (or disks) in which planets form. Their new model tracks changes in the composition of the disk as it ages.

The researchers found that, in disks with carbon-oxygen ratios greater than 0.8, carbon-rich planets can form farther from the center of the disk than previously understood. They also found that carbon-rich planets can form in disks with a carbon-oxygen ratio as low as 0.65 if those planets form close to their host star.

Previous models predicted carbon-rich planets could only form in disks with carbon-oxygen ratios higher than 0.8. This is important, the researchers said, because there are many more stars with carbon-oxygen ratios greater than 0.65 than there are with carbon-oxygen ratios greater than 0.8.

Said Madhusudhan, "Our study shows that extraterrestrial worlds can be extremely diverse in their chemical compositions, including many that are drastically different from our earthly experience."

The Yale Center for Astronomy and Astrophysics provided support for the research.

There are more than 1,000 confirmed exoplanets and more than 3,000 exoplanet "candidates."

"An important question is whether or not our Earth is a typical rocky planet," said Fischer. "Despite the growing number of exoplanet discoveries, we still don't have an answer to this question. This work further expands the range of factors that may bear on the habitability of other worlds."


Story Source:

The above story is based on materials provided by Yale University. The original article was written by Eric Gershon. Note: Materials may be edited for content and length.


Journal Reference:

  1. John Moriarty, Nikku Madhusudhan, Debra Fischer. CHEMISTRY IN AN EVOLVING PROTOPLANETARY DISK: EFFECTS ON TERRESTRIAL PLANET COMPOSITION. The Astrophysical Journal, 2014; 787 (1): 81 DOI: 10.1088/0004-637X/787/1/81

Cite This Page:

Yale University. "Diamond planets may be more common than astronomers thought." ScienceDaily. ScienceDaily, 27 May 2014. <www.sciencedaily.com/releases/2014/05/140527220554.htm>.
Yale University. (2014, May 27). Diamond planets may be more common than astronomers thought. ScienceDaily. Retrieved September 3, 2014 from www.sciencedaily.com/releases/2014/05/140527220554.htm
Yale University. "Diamond planets may be more common than astronomers thought." ScienceDaily. www.sciencedaily.com/releases/2014/05/140527220554.htm (accessed September 3, 2014).

Share This



More Space & Time News

Wednesday, September 3, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: NASA Captures Solar Flare

Raw: NASA Captures Solar Flare

AP (Sep. 1, 2014) NASA reported the sun emitted a mid-level solar flare, on August 24th. NASA's Solar Dynamics Observatory captured the images of the flare, which erupted on the left side of the sun. (Sept. 1) Video provided by AP
Powered by NewsLook.com
Space Shuttle Discovery's Legacy, 30 Years Later

Space Shuttle Discovery's Legacy, 30 Years Later

Newsy (Aug. 30, 2014) The space shuttle Discovery launched for the very first time 30 years ago. Here's a look back at its legacy. Video provided by Newsy
Powered by NewsLook.com
Experiment Tests Whether Universe Is Actually A Hologram

Experiment Tests Whether Universe Is Actually A Hologram

Newsy (Aug. 27, 2014) Researchers at Fermilab are using a device called "The Holometer" to test whether our universe is actually a 2-D hologram that just seems 3-D. Video provided by Newsy
Powered by NewsLook.com
SpaceX’s Falcon 9 Rocket Explodes After Liftoff

SpaceX’s Falcon 9 Rocket Explodes After Liftoff

Newsy (Aug. 23, 2014) The private spaceflight company says it is preparing a thorough investigation into Friday's mishap. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins