News / Science & Technology

Exoplanet Could Change Theory on How Planets Form

This graphic shows a gap in a proto-planetary disk of dust and gas whirling around the nearby red dwarf star TW Hydrae.
This graphic shows a gap in a proto-planetary disk of dust and gas whirling around the nearby red dwarf star TW Hydrae.

Related Articles

New Method of Finding Planets Scores First Discovery

Newly-discovered planet was detected using a method that relies on physicist Albert Einstein's special theory of relativity

Volunteer Astronomers Find 15 New Exoplanets

Amateur astronomers say 15 objects circling distant stars may be capable of supporting life

Earth-sized Planet Discovered

Discovery represents major step towards detection of a twin Earth near the Sun
VOA News
What appears to be a planet about 176 light years away from Earth may cause scientists to rethink prevailing theories on how planets are formed.

The potential planet is orbiting the red dwarf star TW Hydrae. According to NASA, it is an astonishing 12 billion kilometers away from its star.

Scientists using NASA’s Hubble Space Telescope spotted a “mysterious gap” in the proto-planetary disk of gas and debris surrounding TW Hydrae. The gap is 3 billion kilometers wide and the disc itself is 66 billion kilometers wide. NASA says gap is likely caused by a “growing, unseen planet that is gravitationally sweeping up material and carving out a lane in the disk, like a snow plow.”

TW Hydrae is a young star at only 8 million years old, and the prevailing theory on planet formation holds that planets take tens of millions of years to form. That this planet is so far from its sun means it would take more than 200 times longer to form than Jupiter because of the distance and the lack of material in the outer parts of the proto-planetary disk. In fact, scientists say that in the area of the suspected planet, there are no large dust grains.

"Typically, you need pebbles before you can have a planet. So, if there is a planet and there is no dust larger than a grain of sand farther out, that would be a huge challenge to traditional planet formation models," said John Debes of the Space Telescope Science Institute in Baltimore, Maryland. Debes is chief of a research team that identified the gap.

According to NASA, this planet may have formed because a part of the disk became gravitationally unstable and collapsed on itself. If true, a planet could form over just a few thousand years.

"If we can actually confirm that there's a planet there, we can connect its characteristics to measurements of the gap properties," Debes said. "That might add to planet formation theories as to how you can actually form a planet very far out."

The planet is estimated to be six to 28 times the mass of Earth, and if it were in our solar system, it would be roughly twice as far as Pluto from our sun.

"It's so intriguing to see a system like this," said Debes. "This is the lowest-mass star for which we've observed a gap so far out."

The team's paper appears online in The Astrophysical Journal.

You May Like

Video One Year After Thai Coup, No End in Sight for Military Rule

Since carrying out the May 22, 2014 coup, the general has retired from the military but is still firmly in charge More

Goodbye, New York

This is what the fastest-growing big cities in America have in common More

Job-Seeking Bangladeshis Risk Lives to Find Work

The number of Bangladeshi migrants on smugglers’ boats bound for Southeast Asian countries has soared in the past two years 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.
Turkey's Main Opposition Party Hopes for Election Breakthroughi
X
May 22, 2015 10:23 AM
Turkey’s main opposition Republican People’s Party has sought an image change ahead of the June 7 general election. The move comes after suffering successive defeats at the hands of the Islamist-rooted AK Party, which has portrayed it as hostile to religion. Dorian Jones reports from the western city of Izmir.
Video

Video Turkey's Main Opposition Party Hopes for Election Breakthrough

Turkey’s main opposition Republican People’s Party has sought an image change ahead of the June 7 general election. The move comes after suffering successive defeats at the hands of the Islamist-rooted AK Party, which has portrayed it as hostile to religion. Dorian Jones reports from the western city of Izmir.
Video

Video Europe Follows US Lead in Tackling ‘Conflict Minerals’

Metals mined from conflict zones in places like the Democratic Republic of Congo are often sold by warlords to buy weapons. This week European lawmakers voted to force manufacturers to prove that their supply chains are not inadvertently fueling conflicts and human rights abuses. Henry Ridgwell reports from London.
Video

Video Class Tackles Questions of Race, Discrimination

Unrest in some U.S. cities is more than just a trending news item at Ladue Middle School in St. Louis, Missouri. As VOA’s Kane Farabaugh reports, it’s a focus of a multicultural studies class engaging students in wide-ranging discussions about racial tensions and police aggression.
Video

Video Mind-Controlled Prosthetics Are Getting Closer

Scientists and engineers are making substantial advances towards the ultimate goal in prosthetics – creation of limbs that can be controlled by the wearer’s mind. Thanks to sophisticated sensors capable of picking up the brain’s signals, an amputee in Iceland is literally bringing us one step closer to that goal. VOA’s George Putic reports.
Video

Video Afghan Economy Sinks As Foreign Troops Depart

As international troops prepare to leave Afghanistan, and many foreign aid groups follow, Afghans are grappling with how the exodus will affect the country's fragile economy. Ayesha Tanzeem reports from the Afghan capital, Kabul.
Video

Video Poverty, Ignorance Force Underage Girls Into Marriage

The recent marriage of a 17-year old Chechen girl to a local police chief who was 30 years older and already had a wife caused an outcry in Russia and beyond. The bride was reportedly forced to marry and her parents were intimidated into giving their consent. The union spotlighted yet again the plight of many underage girls in developing countries. Zlatica Hoke reports poverty, ignorance and fear are behind the practice, especially in Asia and Africa.
Video

Video South Korea Marks Gwangju Uprising Anniversary

South Korea this week marked the 35th anniversary of a protest that turned deadly. The Gwangju Uprising is credited with starting the country’s democratic revolution after it was violently quelled by South Korea’s former military rulers. But as Jason Strother reports, some observers worry that democracy has recently been eroded.
Video

Video California’s Water System Not Created To Handle Current Drought

The drought in California is moving into its fourth year. While the state's governor is mandating a reduction in urban water use, most of the water used in California is for agriculture. But both city dwellers and farmers are feeling the impact of the drought. Some experts say the state’s water system was not created to handle long periods of drought. Elizabeth Lee reports from Ventura County, an agricultural region just northwest of Los Angeles.
Video

Video How to Clone a Mammoth: The Science of De-Extinction

An international team of scientists has sequenced the complete genome of the woolly mammoth. Led by the Swedish Museum of Natural History in Stockholm, the work opens the door to recreate the huge herbivore, which last roamed the Earth 4,000 years ago. VOA’s Rosanne Skirble considers the science of de-extinction and its place on the planet
Video

Video Blind Boy Defines His Life with Music

Cole Moran was born blind. He also has cognitive delays and other birth defects. He has to learn everything by ear. Nevertheless, the 12-year-old has had an insatiable love for music since he was born. VOA’s June Soh introduces us to the young phenomenal harmonica player.

VOA Blogs