Featured Research

from universities, journals, and other organizations

New planet-weighing technique found

Date:
June 27, 2012
Source:
Carnegie Institution
Summary:
Although there have been about 800 extra-solar planets discovered so far in our galaxy, the precise masses of the majority of them are still unknown, as the most-common planet-finding technique provides only a general idea of an object's mass. Previously, the only way to determine a planet's exact mass was if it transits. Astronomers have, for the first time, determined the mass of a non-transiting planet.

Although there have been about 800 extra-solar planets discovered so far in our galaxy, the precise masses of the majority of them are still unknown, as the most-common planet-finding technique provides only a general idea of an object's mass. Previously, the only way to determine a planet's exact mass was if it transits -- has an orbit that periodically eclipses that of its host star. Former Carnegie scientist Mercedes L๓pez-Morales has, for the first time, determined the mass of a non-transiting planet.

Related Articles


The work will be published in Astrophysical Journal Letters.

Knowing a body's mass is essential first to confirm it is a planet and if so, to determine whether it is rocky and possibly habitable or large and gassy. Until now, only the masses of transiting planets have been measured. Transiting planets are also the only type of extra-solar objects on which atmospheres have been detected.

L๓pez-Morales, along with her colleagues Florian Rodler and Ignasi Ribas of the Institute of Space Sciences, ICE (CSIC-IEEC, in Barcelona, Spain) measured the exact mass of a non-transiting planet. They did this using a new method that involves studying the carbon monoxide signature of the planet's atmosphere -- detecting, in the process, the atmosphere of this non-transiting planet.

The planet is called Tau Boo b, located in the constellation of Bootes, and it orbits a star about 50 light years from Earth that's bright enough to be visible to the naked eye. The planet is similar in size to Jupiter and is so close to its star (only 8 stellar radii), that a year for this planet asts only 3.3 Earth days. Furthermore, its surface temperature reaches 1,500 ฐ C, making it inhospitable to life.

Discovered in 1996, Tau Boo b was one of the first planets originally detected by the radial velocity method. This planet does not transit, but its presence and characteristics were initially determined by the wobble of its host star. This technique only provides a rough indication of a detected planet's mass.

In June 2011, L๓pez-Morales' team conducted five hours of observations at near infrared wavelength (2.3 microns). They obtained data from the high-resolution spectrograph CRIRES, an instrument mounted on one of the four 8.2m Very Large Telescopes (VLT) of the European Southern Observatory (ESO) in Chile.

The observations and subsequent data analysis revealed the presence of carbon monoxide in the planet's atmosphere. In addition, by studying the planet's orbital motion through the displacement of spectral lines of carbon monoxide, the team was able to calculate its exact mass -- 5.6 times Jupiter -- a first using this particular method, and also a first for a non-transiting planet.

An independent study conducted by researchers at the University of Leiden in the Netherlands obtained a similar result for the same planetary system, confirming the potential of this technique.

"This method represents a strong advance in the field of exoplanets," said Lopez-Morales. "It opens a new path to determine masses of exoplanets and the composition of their atmospheres"

The research team expects many more planets will be weighted using this new technique. They are also convinced that in the future, they will be able to detect molecules that are associated with the presence of life in non-transiting distant planets."

This work has been partially supported by the NSF.


Story Source:

The above story is based on materials provided by Carnegie Institution. Note: Materials may be edited for content and length.


Cite This Page:

Carnegie Institution. "New planet-weighing technique found." ScienceDaily. ScienceDaily, 27 June 2012. <www.sciencedaily.com/releases/2012/06/120627142516.htm>.
Carnegie Institution. (2012, June 27). New planet-weighing technique found. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2012/06/120627142516.htm
Carnegie Institution. "New planet-weighing technique found." ScienceDaily. www.sciencedaily.com/releases/2012/06/120627142516.htm (accessed October 31, 2014).

Share This



More Space & Time News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Antares Liftoff Explosion

Raw: Antares Liftoff Explosion

AP (Oct. 29, 2014) — Observers near Wallops Island recorded what they thought would be a routine rocket launch Tuesday night. What they recorded was a major rocket explosion shortly after lift off. (Oct 29) Video provided by AP
Powered by NewsLook.com
Raw: Russian Cargo Ship Docks at Space Station

Raw: Russian Cargo Ship Docks at Space Station

AP (Oct. 29, 2014) — Just hours after an American cargo run to the International Space Station ended in flames, a Russian supply ship has arrived at the station with a load of fresh supplies. (Oct. 29) Video provided by AP
Powered by NewsLook.com
Journalist Captures Moment of Antares Rocket Explosion

Journalist Captures Moment of Antares Rocket Explosion

Reuters - US Online Video (Oct. 29, 2014) — A space education journalist is among those who witness and record the explosion of an unmanned Antares rocket seconds after its launch. Rough Cut (no reporter narration) Video provided by Reuters
Powered by NewsLook.com
Rocket Explosion Under Investigation

Rocket Explosion Under Investigation

AP (Oct. 28, 2014) — NASA and Orbital Sciences officials say they are investigating the explosion of an unmanned commercial supply rocket bound for the International Space Station. It blew up moments after liftoff Tuesday evening over the launch site in Virginia. (Oct. 28) Video provided by AP
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:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

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