Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

First Earth-Sized, Rocky Exoplanet Found

05.11.2013
A team of astronomers has found the first Earth-sized planet outside the solar system that has a rocky composition like that of Earth.

This exoplanet, known as Kepler-78b, orbits its star very closely every 8.5 hours, making it much too hot to support life. The results are being published in the journal Nature.

This Earth-sized planet was discovered using data from NASA’s Kepler Space Telescope, and confirmed and characterized with the W. M. Keck Observatory.

Every 8.5 hours the planet passes in front of its host star, blocking a small fraction of the starlight. These telltale dimmings were picked up by researchers analyzing the Kepler data.

The team led by Dr. Andrew Howard (Institute for Astronomy, University of Hawaii at Manoa) then measured the mass of the planet with the Keck Observatory on Mauna Kea, in Hawaii. Using the ten-meter Keck I telescope fitted with the HIRES instrument, the team employed the radial velocity method to measure how much an orbiting planet causes its star to wobble, to determine the planet’s mass. This is another excellent example of the synergy between the Kepler survey, which has identified more than 3,000 potential exoplanet candidates, and Keck Observatory, which plays a leading role in conducting precise Doppler measurements of the exoplanet candidates.

A handful of planets the size or mass of Earth have been discovered recently. This is the first one with both quantities measured. “When you have both the size and the mass of an object, you can calculate its density, and thereby determine its composition,” explained Howard.

With a radius about 1.2 times of Earth's and a mass equal to about 1.7 times Earth’s, Kepler-78b has a density the same as Earth’s, suggesting that it is also made primarily of rock and iron. Its star is slightly smaller and less massive than the sun and is located about 400 light-years from Earth in the constellation Cygnus.

Kepler-78b is a member of a new class of “ultrashort period” planets recently identified by the Kepler spacecraft. These newfound worlds all orbit their stars with orbital periods of less than 12 hours. They’re also small, about one-to-two times the size of Earth. Kepler-78b is the first planet in this new class to have its mass measured. It is a mystery how these planets formed and made it so close to their host stars (only 1 percent of the Earth-Sun separation in the case of Kepler-78b).

A companion study led by Dr. Francesco Pepe (University of Geneva, Switzerland) used the same Kepler data but independent radial velocity observations and is being published in the same issue.

The two studies found similar results. “The gold standard in science is having your findings reproduced by other researchers,” explained Howard. “In this case, we did not have to wait for this to happen.”

The other members of Howard’s team are Roberto Sanchis-Ojeda (MIT), who analyzed the transit data taken by the Kepler spacecraft to find the planet and calculate its size, Dr. Geoffrey Marcy (University of California, Berkeley), Dr. John Johnson (Harvard), Dr. Debra Fischer (Yale), Benjamin Fulton and Evan Sinukoff (UHM graduate students), and Dr. Jonathan Fortney (University of California, Santa Cruz).

HIRES (the High-Resolution Echelle Spectrometer) produces spectra of single objects at very high spectral resolution, yet covering a wide wavelength range. It does this by separating the light into many "stripes" of spectra stacked across a mosaic of three large CCD detectors. HIRES is famous for finding planets orbiting other stars. Astronomers also use HIRES to study distant galaxies and quasars, finding clues to the Big Bang.

The W. M. Keck Observatory operates the largest, most scientifically productive telescopes on Earth. The two, 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectroscopy and world-leading laser guide star adaptive optics systems. The Observatory is a private 501(c) 3 non-profit organization and a scientific partnership of the California Institute of Technology, the University of California and NASA.

Science Contact:
Dr. Andrew Howard
howard@ifa.hawaii.edu
808-208-1224

Steve Jefferson | Newswise
Further information:
http://www.keckobservatory.org

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: New proton record: Researchers measure magnetic moment with greatest possible precision

High-precision measurement of the g-factor eleven times more precise than before / Results indicate a strong similarity between protons and antiprotons

The magnetic moment of an individual proton is inconceivably small, but can still be quantified. The basis for undertaking this measurement was laid over ten...

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

IceCube experiment finds Earth can block high-energy particles from nuclear reactions

24.11.2017 | Physics and Astronomy

A 'half-hearted' solution to one-sided heart failure

24.11.2017 | Health and Medicine

Heidelberg Researchers Study Unique Underwater Stalactites

24.11.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>