Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Astronomers are First to Successfully Predict Extra-Solar Planet

Astronomers, including one at The University of Arizona, have successfully predicted the existence of an unknown planet, the first since Neptune was predicted in the 1840s. This planet, however, is outside our own solar system, circling a star a little more than 200 light years from Earth.
The UA's Rory Barnes and his associates predicted the unknown planet from their theoretical study of the orbits of two planets known to orbit star HD 74156. Barnes announced the discovery today at the American Astronomical Society meeting in Austin, Texas.

Barnes, who was an astronomy and physics undergraduate at UA, is now a post-doctoral associate at the UA's Lunar and Planetary Laboratory. He and his colleagues studied the orbits of several planetary systems and found that planets¹ orbits tend to be packed as closely together as possible without gravity destabilizing their orbits. They reasoned that this tight packing resulted from universal processes of planetary formation.

But the two planets, named ³B² and ³C², orbiting the star HD 74156 had a big gap between them. They concluded that if their ³Packed Planetary Systems² hypothesis was correct, then there must be another planet between planets B and C, and it must be in a particular orbit.

³When I realized that six out of seven multiplanet systems appeared Œpacked,¹² Barnes said, ³I naturally expected there must be another planet in the HD 74156 system so that it, too, would be packed.²

Jacob Bean and his colleagues from the University of Texas observed the planetary system carefully and confirmed that a new planet was located where Barnes had predicted. The new planet is named, by convention, HD 74156 D.

Those who collaborated with Barnes in making the successful prediction are Sean Raymond, now a post-doctoral associate at the University of Colorado, and professor Thomas Quinn of the University of Washington. The discovery team, from the University of Texas at Austin, includes Jacob Bean¹s adviser, professor Barbara McArthur, and professor Fritz Benedict.

Steven Soter, astronomer with the American Museum of Natural History in New York, has been following the discoveries of "extra-solar" planets, or planets orbiting other stars beyond our solar system. Soter noted that Barnes, Raymond and Quinn are the first to successfully predict the existence of an unknown planet since Neptune was predicted more than 160 years ago. Mid-19th century astronomers John Couch Adams in England and Urbain-Jean-Joseph Le Verrier in France independently calculated the position of Neptune based on irregularities in the motion of Uranus.

"As well as providing a way to predict planet discoveries, the Packed Planetary Systems hypothesis reveals something fundamental about the formation of planets," Barnes said. "The process by which planets grow from the clouds of dust and gas around young stars must be very efficient.
Wherever there is room for a planet to form, it does."

The Packed Planetary Systems hypothesis also predicts that gaps between known planets in other systems are probably occupied by other, still undiscovered planets. Barnes noted that shortly after the discovery of HD
74156 d, a different team of astronomers found a planet orbiting the star 55 Cancri, again in an orbit that Barnes and Raymond predicted.

Barnes and colleagues also have predicted a specific planet orbiting a third system, HD 38529. So far, no planet has been discovered there. However, the scientists say they expect future observations may confirm another successful prediction by the Packed Planetary Systems hypothesis.

CONTACT: Rory Barnes (520-626-3154;

Lori Stiles | UA Science news
Further information:

More articles from Physics and Astronomy:

nachricht First results of NSTX-U research operations
26.10.2016 | DOE/Princeton Plasma Physics Laboratory

nachricht Scientists discover particles similar to Majorana fermions
25.10.2016 | Chinese Academy of Sciences Headquarters

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Greater Range and Longer Lifetime

26.10.2016 | Power and Electrical Engineering

VDI presents International Bionic Award of the Schauenburg Foundation

26.10.2016 | Awards Funding

3-D-printed magnets

26.10.2016 | Power and Electrical Engineering

More VideoLinks >>>