National Aeronautics and Space Administration Logo
Follow this link to skip to the main content NASA Banner
Solar System Exploration
News & Events
More Planets Emerge with Solar System-Like Orbits
More Planets Emerge with Solar System-Like Orbits
15 Oct 2001
(Source: NASA Headquarters)

Don Savage
Headquarters, Washington
(Phone: 202/358-1547)

Amber Jones
National Science Foundation, Arlington, Va.
(Phone: 703/292-8070)

RELEASE: 01-197

An international team of astronomers has discovered eight new extrasolar planets, bringing to nearly 80 the number of planets found orbiting nearby stars.

The latest discoveries, supported by NASA and the National Science Foundation (NSF), uncovered more evidence of what the astronomers are calling a new class of planets. These planets have circular orbits similar to the orbits of planets in our solar system.

At least two of the recently detected planets have approximately circular orbits. This characteristic is shared by two planets (one of them the size of Jupiter) previously detected by the same team around 47 Ursae Majoris, a star in the Big Dipper constellation, and one around the star Epsilon Reticulum. The majority of the extrasolar planets found to date are in an elongated, or "eccentric," orbit.

The further a planet lies from its star, the longer it takes to complete an orbit and the longer astronomers have to observe to detect it.

"As our search continues, we're finding planets in larger and larger orbits," said Steve Vogt of the Lick Observatory, University of California at Santa Cruz. "Most of the planetary systems we've found have looked like very distant relatives of the solar system - no family likeness at all. Now we're starting to see something like second cousins.

"In a few years' time we could be finding brothers and sisters," he added.

"This result is very exciting," said Anne Kinney, director of NASA's Astronomy and Physics Division at Headquarters in Washington. "To understand the formation and evolution of planets and planetary systems we need a large sample of planets to study. This result, added to others in the recent past, marks the beginning of an avalanche of data which will help to provide the answers."

The recently detected planets range in mass from 0.8 to 10 times the mass of Jupiter, the largest planet in our solar system. They orbit their stars at distances ranging from about 0.07 AU (astronomical unit, or the distance from the Sun to Earth), to three AU.

The astronomers - from the United States, Australia, Belgium and the United Kingdom - are searching the nearest 1,200 stars for planets similar to those in our solar system, particularly Jupiter-like gas giants. Their findings will help astronomers assess the solar system's place in the galaxy and whether planetary systems like our own are common or rare.

For most of their discoveries, the astronomers have used the Keck 10-meter telescope on Mauna Kea, Hawaii; the Lick three- meter in Santa Cruz, Calif.; and the 3.9-meter Anglo- Australian Telescope in New South Wales, Australia. To find evidence of planets, the astronomers use a high-precision technique developed by Paul Butler and Geoff Marcy of the University of California at Berkeley to measure how much a star "wobbles" in space as it is affected by a planet's gravity.

The team also receives support from the UK and Australian governments.

News Archive Search  Go!
Show  results per page
Awards and Recognition   Solar System Exploration Roadmap   Contact Us   Site Map   Print This Page
NASA Official: Kristen Erickson
Advisory: Dr. James Green, Director of Planetary Science
Outreach Manager: Alice Wessen
Curator/Editor: Phil Davis
Science Writers: Courtney O'Connor and Bill Dunford
Producer: Greg Baerg
Webmaster: David Martin
> NASA Science Mission Directorate
> Budgets, Strategic Plans and Accountability Reports
> Equal Employment Opportunity Data
   Posted Pursuant to the No Fear Act
> Information-Dissemination Policies and Inventories
> Freedom of Information Act
> Privacy Policy & Important Notices
> Inspector General Hotline
> Office of the Inspector General
> NASA Communications Policy
> NASA Advisory Council
> Open Government at NASA
Last Updated: 15 Oct 2001