Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New planet found: Icy ’super-Earth’ dominates distant solar system

14.03.2006


An international collaboration of astronomers has discovered a "super-Earth" orbiting in the cold outer regions of a distant solar system about 9,000 light-years away. The planet weighs 13 times as much as Earth, and at -330 degrees Fahrenheit, it’s one of the coldest planets ever discovered outside our solar system.



Andrew Gould, leader of the MicroFUN collaboration and professor of astronomy at Ohio State University , pointed to two key implications of the discovery. "First," Gould said, "this icy super-Earth dominates the region around its star that in our solar system is populated by the gas-giant planets, Jupiter and Saturn. We’ve never seen a system like this before, because we’ve never had the means to find them."

"And second," he added, "these icy super-Earths are pretty common. Roughly 35 percent of all stars have them."


The astronomers have submitted a paper on the planet to Astrophysical Journal Letters, and posted a copy on the Internet preprint server arXiv.org.

MicroFUN searches for planets using a phenomenon called gravitational microlensing, which occurs when a massive object such as a star crosses in front of another star shining in the background. The object’s strong gravity bends the light rays from the more distant star and magnifies them like a lens. Here on Earth, we see the magnified star get brighter as the lens star crosses in front of it, and then fade as the lens gets farther away.

The OGLE (Optical Gravitational Lensing Experiment) collaboration initially discovered the microlensed star in April 2005. Piecing together their observations, Gould and OGLE leader Andrzej Udalski of Warsaw University Observatory suddenly realized on May 1 that the star was brightening extremely quickly, meaning that it would be exceptionally fertile ground for planet hunting. "It was 4:00 a.m.," Gould said. "I was very excited and frantic to get someone to observe that star."

So Gould called the MDM Observatory in Arizona, where the astronomer on duty happened to be Ohio State graduate student Deokkeun An.

Gould asked An to spare a few minutes during his night’s work to occasionally measure the star’s brightness. But when An and his co-observer Ai-ying Zhou of Missouri State University heard how intense the signal was, they decided to put aside their own project to take more than 1,000 measurements of the event.

"It’s a good thing that they did -- their observations turned out to be critical to our determination that there was a planet," Gould said.

"I thought this was a good chance to take many images of the event, to erase any doubt as to whether this was a planet signal," An remembered. "Since the target could only be seen through the telescope during a short time window, we did not hesitate to follow it."

The event was also observed by astronomers in New Zealand and Hawaii.

But after the astronomers gathered all the data, they faced more difficulties. There remained a chance that the tiny warping they saw in the signal wasn’t caused by a planet, and Ohio State graduate student Subo Dong had to write special software to speed their computer models to weed out the other possibilities.

Finally, the models confirmed the presence of a Neptune-mass planet, 13 times heavier than Earth, orbiting a star about half as big as our sun.

Gould suspects that the planet is a bare, icy terrestrial one -- a cold super-Earth. Judging from the absence of Jupiter-like planets in its vicinity, that solar system may lack the gas necessary to make gas planets, he said.

"We can’t really tell for sure," he admitted. "If we start getting more statistics on this type of planet, we could piece together a better story."

Until a decade ago, scientists had no evidence of what other solar systems were like. Since then, some 170 planets have been discovered, and most of them have been gas giants similar to Jupiter.

Only a handful of Neptune-mass planets have ever been detected, and only two in the cold outer regions of their solar systems. "The next step is to push the sensitivity of our detection methods down to reach Earth-mass planets," Gould said, "and microlensing is the best way to get there."

The technique is the only one sensitive enough to detect these types of planets, he added. To increase the chance of finding planets like Earth, he would like to see a new generation of telescopes dedicated to microlensing planet searches.

Gould’s work was supported by the National Science Foundation and NASA.

Andrew Gould | EurekAlert!
Further information:
http://www.astronomy.ohio-state.edu

More articles from Physics and Astronomy:

nachricht A 100-year-old physics problem has been solved at EPFL
23.06.2017 | Ecole Polytechnique Fédérale de Lausanne

nachricht Quantum thermometer or optical refrigerator?
23.06.2017 | National Institute of Standards and Technology (NIST)

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: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>