Featured Research

from universities, journals, and other organizations

NASA's WISE survey finds thousands of new stars, but no 'Planet X'

Date:
March 7, 2014
Source:
NASA/Jet Propulsion Laboratory
Summary:
After searching hundreds of millions of objects across our sky, NASA's Wide-Field Infrared Survey Explorer (WISE) has turned up no evidence of the hypothesized celestial body in our solar system commonly dubbed "Planet X."

A nearby star stands out in red in this image from the Second Generation Digitized Sky Survey.
Credit: DSS/NASA/JPL-Caltech

After searching hundreds of millions of objects across our sky, NASA's Wide-Field Infrared Survey Explorer (WISE) has turned up no evidence of the hypothesized celestial body in our solar system commonly dubbed "Planet X."

Researchers previously had theorized about the existence of this large, but unseen celestial body, suspected to lie somewhere beyond the orbit of Pluto. In addition to "Planet X," the body had garnered other nicknames, including "Nemesis" and "Tyche."

This recent study, which involved an examination of WISE data covering the entire sky in infrared light, found no object the size of Saturn or larger exists out to a distance of 10,000 astronomical units (au), and no object larger than Jupiter exists out to 26,000 au. One astronomical unit equals 93 million miles. Earth is 1 au, and Pluto about 40 au, from the sun.

"The outer solar system probably does not contain a large gas giant planet, or a small, companion star," said Kevin Luhman of the Center for Exoplanets and Habitable Worlds at Penn State University, University Park, Pa., author of a paper in the Astrophysical Journal describing the results.

But searches of the WISE catalog are not coming up empty. A second study reveals several thousand new residents in our sun's "backyard," consisting of stars and cool bodies called brown dwarfs.

"Neighboring star systems that have been hiding in plain sight just jump out in the WISE data," said Ned Wright of the University of California, Los Angeles, the principal investigator of the mission.

The second WISE study, which concentrated on objects beyond our solar system, found 3,525 stars and brown dwarfs within 500 light-years of our sun.

"We're finding objects that were totally overlooked before," said Davy Kirkpatrick of NASA's Infrared and Processing Analysis Center at the California Institute of Technology, Pasadena, Calif. Kirkpatrick is lead author of the second paper, also in the Astrophysical Journal. Some of these 3,525 objects also were found in the Luhman study, which catalogued 762 objects.

The WISE mission operated from 2010 through early 2011, during which time it performed two full scans of the sky -- with essentially a six-month gap between scans. The survey captured images of nearly 750 million asteroids, stars and galaxies. In November 2013, NASA released data from the AllWISE program, which now enables astronomers to compare the two full-sky surveys to look for moving objects.

In general, the more an object in the WISE images appears to move over time, the closer it is. This visual clue is the same effect at work when one observes a plane flying low to the ground versus the same plane flying at higher altitude. Though traveling at the same speed, the plane at higher altitude will appear to be moving more slowly.

Searches of the WISE data catalog for these moving objects are uncovering some of the closest stars. The discoveries include a star located about 20 light-years away in the constellation Norma, and as reported last March, a pair of brown dwarfs only 6.5 light-years away -- making it the closest star system to be discovered in nearly a century.

Despite the large number of new solar neighbors found by WISE, "Planet X" did not show up. Previous speculations about this hypothesized body stemmed in part from geological studies that suggested a regular timing associated with mass extinctions on Earth. The idea was that a large planet or small star hidden in the farthest reaches of our solar system might periodically sweep through bands of outer comets, sending them flying toward our planet. The Planet X-based mass extinction theories were largely ruled out even prior to the new WISE study.

Other theories based on irregular comet orbits had also postulated a Planet X-type body. The new WISE study now argues against these theories as well.

Both of the WISE searches were able to find objects the other missed, suggesting many other celestial bodies likely await discovery in the WISE data.

"We think there are even more stars out there left to find with WISE. We don't know our own sun's backyard as well as you might think," said Wright.

WISE was put into hibernation upon completing its primary mission in 2011. In September 2013, it was reactivated, renamed NEOWISE and assigned a new mission to assist NASA's efforts to identify the population of potentially hazardous near-Earth objects. NEOWISE will also characterize previously known asteroids and comets to better understand their sizes and compositions.

JPL managed and operated WISE for NASA's Science Mission Directorate. The mission was selected competitively under NASA's Explorers Program managed by the agency's Goddard Space Flight Center in Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah. The spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA. More information is online at: http://www.nasa.gov/wise and http://wise.astro.ucla.edu and http://jpl.nasa.gov/wise.


Story Source:

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


Journal References:

  1. K. L. Luhman. A Search for a Distant Companion to the Sun with the Wide-field Infrared Survey Explorer. The Astrophysical Journal, 2014; 781 (1): 4 DOI: 10.1088/0004-637X/781/1/4
  2. J. Davy Kirkpatrick, Adam Schneider, Sergio Fajardo-Acosta, Christopher R. Gelino, Gregory N. Mace, Edward L. Wright, Sarah E. Logsdon, Ian S. McLean, Michael C. Cushing, Michael F. Skrutskie, Peter R. Eisenhardt, Daniel Stern, Mislav Baloković, Adam J. Burgasser, Jacqueline K. Faherty, George B. Lansbury, J. A. Rich, Nathalie Skrzypek, John W. Fowler, Roc M. Cutri, Frank J. Masci, Tim Conrow, Carl J. Grillmair, Howard L. McCallon, Charles A. Beichman, Kenneth A. Marsh. The AllWISE Motion Survey and The Quest for Cold Subdwarfs. The Astrophysical Journal, 2014; 783 (2): 122 DOI: 10.1088/0004-637X/783/2/122

Cite This Page:

NASA/Jet Propulsion Laboratory. "NASA's WISE survey finds thousands of new stars, but no 'Planet X'." ScienceDaily. ScienceDaily, 7 March 2014. <www.sciencedaily.com/releases/2014/03/140307160630.htm>.
NASA/Jet Propulsion Laboratory. (2014, March 7). NASA's WISE survey finds thousands of new stars, but no 'Planet X'. ScienceDaily. Retrieved August 2, 2014 from www.sciencedaily.com/releases/2014/03/140307160630.htm
NASA/Jet Propulsion Laboratory. "NASA's WISE survey finds thousands of new stars, but no 'Planet X'." ScienceDaily. www.sciencedaily.com/releases/2014/03/140307160630.htm (accessed August 2, 2014).

Share This




More Space & Time News

Saturday, August 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Study Says The Moon Was Deformed Early In Its History

New Study Says The Moon Was Deformed Early In Its History

Newsy (July 31, 2014) Scientists say when the moon was young, it was deformed by the Earth's gravitational pull, which gave it a lemon-like shape. Video provided by Newsy
Powered by NewsLook.com
Supply Ship Takes Off for International Space Station

Supply Ship Takes Off for International Space Station

AFP (July 30, 2014) The European Space Agency's fifth Automated Transfer Vehicle (ATV-5) is takes off to the International Space Station on an Ariane 5 rocket from French Guiana. Duration: 00:34 Video provided by AFP
Powered by NewsLook.com
Raw: Rocket Launches Into Space With Cargo Ship

Raw: Rocket Launches Into Space With Cargo Ship

AP (July 30, 2014) Arianespace launched a rocket Tuesday from French Guiana carrying a robotic cargo ship to deliver provisions to the International Space Station. (July 30) Video provided by AP
Powered by NewsLook.com
In Virginia, the Rise of a New Space Coast

In Virginia, the Rise of a New Space Coast

AP (July 30, 2014) Every summer, tourists make the pilgrimage to Chincoteague Island, Va. to see wild ponies cross the Assateague Channel. But, it's the rockets sending to supplies to the International Space Station that are making this a year-round destination. (July 30) 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:
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