News / Science & Technology

Astronomers Discover Earth-sized 'Lava Planet'

An artist's conception of Kepler-78b orbiting its parent star once every 8.5 hours. Credit: David A. Aguilar (CfA)
An artist's conception of Kepler-78b orbiting its parent star once every 8.5 hours. Credit: David A. Aguilar (CfA)

Related Articles

'Super Earth' Exoplanet May Have Water Atmosphere

Planet, detected by Japanese astronomers, is located 40 light years from Earth in constellation Ophiuchus

Journal: Life on Earth Will End in 1.75 to 3.25 Billion Years

British researchers looked at planets outside our solar system to come up with estimate of how long Earth will be habitable

Water Discovered in Extrasolar, Rocky World

Scientists think system had potential to contain Earth-like exoplanets
VOA News
Two teams of astronomers have, for the first time, measured an Earth-sized exoplanet, a planet they say should not exist.

But the planet, known as Kepler-78b, is not likely to support any kind of life as we know it. The temperatures on the planet would be scorching as it circles its star every eight-and-a-half hours at a distance of less than one million miles – one of the tightest known orbits.  The orbit is 40 times closer than Mercury’s, for example.

Temperatures on the surface would likely reach an infernal 2,000 to 2,800 Celsius.

Astronomer Francesco Pepe of the University of Geneva in Switzerland, who led one of the teams, said the planet can be “imagined like a lava planet rather than an Earth-like planet.”

The planet, which is 400 light-years from Earth in the constellation Cygnus, has a similar mass to Earth, leading astronomers to believe that it has a similar make up of iron and rock. Kepler-78b is 20 percent larger than Earth and weighs about twice as much, meaning it’s likely to have a similar density.

According to current theories of planet formation, it couldn’t have formed so close to its star, nor could it have moved there.

Because it’s so close to its star, Kepler-78, the planet is doomed, astronomers say. Gravitational tides will continue to draw it even closer to its star. Eventually, it will move so close that the star’s gravity will rip the world apart.

Theorists predict the planet will vanish within three billion years. Our solar system could have held a planet like Kepler-78b. If it had, the planet would have been destroyed long ago leaving no signs for astronomers today.

Astronomers were able to measure the planet’s orbit and size by studying the light from its star as the planet transits, or passes in front of the star. Each time the planet passes, there is a small decrease in the amount of light from the star. Measuring this decrease can determine the planet’s size.

Measuring the mass of an exoplanet involves measuring the slight wobble the planet’s gravity causes on its star as it orbits.

The results from two independent teams were published in the journal Nature on Wednesday.

Sara Seager, a planetary scientist at the Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts, who was not part of either team, told Nature that the results represented “an inevitable march towards other Earths.”

You May Like

N. Korea Sentences American to 6 Years Hard Labor

Matthew Miller's brief trial Sunday comes two weeks after 24-year old Miller and two other American detainees appealed to the US government to help free them More

Pakistan Rejects Afghan Criticism of 480-kilometer Border Trench

Military spokesman tells VOA the project is part of administrative and security measures taken to secure the mountainous border with Afghanistan More

Photogallery Typhoon Kalmaegi Makes Landfall in Philippines

Storm makes landfall late Sunday, cutting power and communications lines and forcing people to flee to higher ground More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Scotland Independence Bid Stokes Global Interesti
X
Henry Ridgwell
September 12, 2014 8:35 PM
The people of Scotland are preparing to vote on whether to become independent and break away from the rest of Britain, in a referendum being watched carefully in many other countries. Some see it as a risky experiment; while others hope a successful vote for independence might energize their own separatist demands. Foreign immigrants to Scotland have a front row seat for the vote. VOA’s Henry Ridgwell spoke to some of them in Edinburgh.
Video

Video Scotland Independence Bid Stokes Global Interest

The people of Scotland are preparing to vote on whether to become independent and break away from the rest of Britain, in a referendum being watched carefully in many other countries. Some see it as a risky experiment; while others hope a successful vote for independence might energize their own separatist demands. Foreign immigrants to Scotland have a front row seat for the vote. VOA’s Henry Ridgwell spoke to some of them in Edinburgh.
Video

Video Washington DC Mural Artists Help Beautify City

Like many cities, Washington has a graffiti problem. Buildings and homes, especially in low-income neighborhoods, are often targets of illegal artwork. But as we hear from VOA’s Julie Taboh, officials in the nation's capital have come up with an innovative program that uses the talents of local artists to beautify the city.
Video

Video Palestinians Turn to Rebuilding Gaza

After almost two months of conflict in Gaza, Palestinians are preparing to rebuild the isolated Mediterranean enclave with assistance from abroad. Meanwhile, an international human rights group has found that Israel likely violated international laws of war during some of its attacks on Gaza. Zlatica Hoke has more.
Video

Video US Muslim Leaders Condemn Islamic State

Leaders of America's Muslim community are condemning the violent extremism of the Islamic State group in Iraq and Syria. The U.S. Muslim leaders say militants are exploiting their faith in a failed effort to justify violent extremism. VOA correspondent Meredith Buel reports.
Video

Video Middle Eastern Church Leaders Highlight Christians’ Plight

Patriarchs of Eastern Rite churches came to Washington this week to draw attention to the attacks against Christians in Syria, Iraq and elsewhere in the Middle East. VOA’s religion correspondent Jerome Socolovsky has more.
Video

Video Americans' Reaction Mixed on Obama Strategy for Islamic State Militants

President Barack Obama’s televised speech on how the United States plans to “degrade and destroy” the group known as the Islamic State reached a prime-time audience of millions. And it came as Americans appear more willing to embrace a bolder, tougher approach to foreign policy. VOA producer Katherine Gypson and reporter Jeff Seldin have this report from Washington.
Video

Video Authorities Allege LA Fashion Industry-Cartel Ties

U.S. officials say they have broken up crime rings that funneled tens of millions of dollars from Mexican drug cartels through fashion businesses in Los Angeles. Mike O'Sullivan reports that authorities announced nine arrests, as 1,000 law enforcement agents fanned out through the city on Wednesday.
Video

Video Bedouin Woman Runs Successful Business in Palestinian City

A Bedouin woman is breaking social taboos by running a successful vacation resort in the Palestinian town of Jericho. Bedouins are a sub-group of Arabs known for their semi-nomadic lifestyle. Zlatica Hoke says the resort in the West Bank's Jordan Valley is a model of success for women in the region.


Carnage and mayhem are part of daily life in northern Nigeria, the result of a terror campaign by the Islamist group Boko Haram. Fears are growing that Nigeria’s government may not know how to counter it, and may be making things worse. More

AppleAndroid