Featured Research

from universities, journals, and other organizations

Cosmic Magnifying Glass: Distant Star Reveals Planet

Date:
April 16, 2004
Source:
NASA/Jet Propulsion Laboratory
Summary:
Like Sherlock Holmes holding a magnifying glass to unveil hidden clues, modern day astronomers used cosmic magnifying effects to reveal a planet orbiting a distant star.

How Microlensing Works: The observatory on Earth sees the source (distant) star when the lens (closer) star and planet pass through the center of the image. The inset shows what may be seen through a ground-based telescope. The image brightens twice, indicating when the star and planet pass through the observatory's line of sight to the distant star.
Credit: Image credit: NASA/JPL-Caltech

ARLINGTON, Va. -- Like Sherlock Holmes holding a magnifying glass to unveil hidden clues, modern day astronomers used cosmic magnifying effects to reveal a planet orbiting a distant star.

This marks the first discovery of a planet around a star beyond Earth's solar system using gravitational microlensing. A star or planet can act as a cosmic lens to magnify and brighten a more distant star lined up behind it. The gravitational field of the foreground star bends and focuses light, like a glass lens bending and focusing starlight in a telescope. Albert Einstein predicted this effect in his theory of general relativity and confirmed it with our sun.

"The real strength of microlensing is its ability to detect low- mass planets," said Dr. Ian Bond of the Institute for Astronomy in Edinburgh, Scotland, lead author of a paper appearing in the May 10 Astrophysical Journal Letters. The discovery was made possible through cooperation between two international research teams: Microlensing Observations in Astrophysics (MOA) and Optical Gravitational Lensing Experiment (OGLE). Well-equipped amateur astronomers might use this technique to follow up future discoveries and help confirm planets around other stars.

The newly discovered star-planet system is 17,000 light years away, in the constellation Sagittarius. The planet, orbiting a red dwarf parent star, is most likely one-and-ahalf times bigger than Jupiter. The planet and star are three times farther apart than Earth and the sun. Together, they magnify a farther, background star some 24,000 light years away, near the Milky Way center.

In most prior microlensing observations, scientists saw a typical brightening pattern, or light curve, indicating a star's gravitational pull was affecting light from an object behind it. The latest observations revealed extra spikes of brightness, indicating the existence of two massive objects. By analyzing the precise shape of the light curve, Bond and his team determined one smaller object is only 0.4 percent the mass of a second, larger object. They concluded the smaller object must be a planet orbiting its parent star.

Dr. Bohdan Paczynski of Princeton University, Princeton, N.J., an OGLE team member, first proposed using gravitational microlensing to detect dark matter in 1986. In 1991, Paczynski and his student, Shude Mao, proposed using microlensing to detect extrasolar planets. Two years later, three groups reported the first detection of gravitational microlensing by stars. Earlier claims of planet discoveries with microlensing are not regarded as definitive, since they had too few observations of the apparent planetary brightness variations.

"I'm thrilled to see the prediction come true with this first definite planet detection through gravitational microlensing," Paczynski said. He and his colleagues believe observations over the next few years may lead to the discovery of Neptune-sized, and even Earth-sized planets around distant stars.

Microlensing can easily detect extrasolar planets, because a planet dramatically affects the brightness of a background star. Because the effect works only in rare instances, when two stars are perfectly aligned, millions of stars must be monitored. Recent advances in cameras and image analysis have made this task manageable. Such developments include the new large field-of-view OGLE-III camera, the MOA-II 1.8 meter (70.8 inch) telescope, being built, and cooperation between microlensing teams.

"It's time-critical to catch stars while they are aligned, so we must share our data as quickly as possible," said OGLE team- leader Dr. Andrzej Udalski of Poland's Warsaw University Observatory. Udalski in Poland and Paczynski in the U.S lead the Polish/American project. It operates at Las Campanas Observatory in Chile, run by the Carnegie Institution of Washington, and includes the world's largest microlensing survey on the 1.3 meter (51-inch) Warsaw Telescope.

###NASA and the National Science Foundation (NSF) fund OGLE in the U.S. The Polish State Committee for Scientific Research and Foundation for Polish Science funds it in Poland. MOA is primarily a New Zealand/Japanese group, with collaborators in the United Kingdom and U.S. New Zealand's Marsden Fund, NASA and National Science Foundation, Japan's Ministry of Education, Culture, Sports, Science, and Technology, and the Japan Society support it for the Promotion of Science.

Images and information about the latest research are available on the Internet at: http://www.jpl.nasa.gov/media/041504


Story Source:

The above story is based on materials provided by NASA/Jet Propulsion Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

NASA/Jet Propulsion Laboratory. "Cosmic Magnifying Glass: Distant Star Reveals Planet." ScienceDaily. ScienceDaily, 16 April 2004. <www.sciencedaily.com/releases/2004/04/040416011141.htm>.
NASA/Jet Propulsion Laboratory. (2004, April 16). Cosmic Magnifying Glass: Distant Star Reveals Planet. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2004/04/040416011141.htm
NASA/Jet Propulsion Laboratory. "Cosmic Magnifying Glass: Distant Star Reveals Planet." ScienceDaily. www.sciencedaily.com/releases/2004/04/040416011141.htm (accessed October 22, 2014).

Share This



More Space & Time News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Russian Cosmonauts Kick Off Final Spacewalk of 2014

Russian Cosmonauts Kick Off Final Spacewalk of 2014

Reuters - US Online Video (Oct. 22, 2014) — Russian cosmonauts Maxim Suraev and Alexander Samokutyaev step outside the International Space Station to perform work on the exterior of the station's Russian module. Rough Cut (no reporter narration) Video provided by Reuters
Powered by NewsLook.com
Comet Siding Spring Grazes Mars' Atmosphere

Comet Siding Spring Grazes Mars' Atmosphere

Newsy (Oct. 19, 2014) — A comet from the farthest reaches of the solar system passed extremely close to Mars this weekend, giving astronomers a rare opportunity to study it. Video provided by Newsy
Powered by NewsLook.com
Latin America Launches Communications Satellite

Latin America Launches Communications Satellite

AFP (Oct. 17, 2014) — Argentina launches a home-built satellite, a first for Latin America. It will ride a French-made Ariane 5 rocket into orbit, and will provide cell phone, digital TV, Internet and data services to the lower half of South America. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
This Week @ NASA, October 17, 2014

This Week @ NASA, October 17, 2014

NASA (Oct. 17, 2014) — Power spacewalk, MAVEN’s “First Light”, Hubble finds extremely distant galaxy and more... Video provided by NASA
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