Featured Research

from universities, journals, and other organizations

Sun Will Vaporize Earth Unless We Can Change Our Orbit

Date:
February 24, 2008
Source:
University of Sussex
Summary:
Astronomers predict that the Earth will be swallowed up by the Sun in about 7.6 billion years unless the Earth's orbit can be altered. Previous calculations had suggested that the Earth would escape ultimate destruction, although be battered and burnt to a cinder. But this did not take into account the effect of the drag caused by the outer atmosphere of the dying Sun.

Scientists have shown that the Sun's slow expansion will cause the temperature at the surface of the Earth to rise. Oceans will evaporate, and the atmosphere will become laden with water vapour, which (like carbon dioxide) is a very effective greenhouse gas. Eventually, the oceans will boil dry and the water vapour will escape into space.
Credit: iStockphoto/Sunagatov Dmitry

New calculations by University of Sussex astronomers predict that the Earth will be swallowed up by the Sun in about 7.6 billion years unless the Earth’s orbit can be altered.

Related Articles


Dr Robert Smith, Emeritus Reader in Astronomy, said his team previously calculated that the Earth would escape ultimate destruction, although be battered and burnt to a cinder. But this did not take into account the effect of the drag caused by the outer atmosphere of the dying Sun.

He says: "We showed previously that, as the Sun expanded, it would lose mass in the form of a strong wind, much more powerful than the current solar wind. This would reduce the gravitational pull of the Sun on the Earth, allowing the Earth's orbit to move outwards, ahead of the expanding Sun.

“If that were the only effect the Earth would indeed escape final destruction. However, the tenuous outer atmosphere of the Sun extends a long way beyond its visible surface, and it turns out the Earth would actually be orbiting within these very low density outer layers. The drag caused by this low-density gas is enough to cause the Earth to drift inwards, and finally to be captured and vaporised by the Sun.”

The new paper was written in collaboration with Dr Klaus-Peter Schroeder, previously at Sussex, who is now in the Astronomy Department of the University of Guanajuato in Mexico.

Life on Earth will have disappeared long before 7.6 billion years, however. Scientists have shown that the Sun's slow expansion will cause the temperature at the surface of the Earth to rise. Oceans will evaporate, and the atmosphere will become laden with water vapour, which (like carbon dioxide) is a very effective greenhouse gas. Eventually, the oceans will boil dry and the water vapour will escape into space. In a billion years from now the Earth will be a very hot, dry and uninhabitable ball.

Can anything be done to prevent this fate? Professor Smith points to a remarkable scheme proposed by a team at Santa Cruz University, who suggest harnessing the gravitational effects of a close passage by a large asteroid to "nudge" the Earth's orbit gradually outwards away from the encroaching Sun. A suitable passage every 6000 years or so would be enough to keep the Earth out of trouble and allow life to survive for at least 5 billion years, and possibly even to survive the Sun's red giant phase.

“This sounds like science fiction,” says Professor Smith. “But it seems that the energy requirements are just about possible and the technology could be developed over the next few centuries.” However, it is a high-risk strategy - a slight miscalculation, and the asteroid could actually hit the Earth, with catastrophic consequences. “A safer solution may be to build a fleet of interplanetary 'life rafts' that could manoeuvre themselves always out of reach of the Sun, but close enough to use its energy,” he adds.

Journal reference: "Astronomical engineering: a strategy for modifying planetary orbits". D G Korycansky of the University of California at Santa Cruz, with colleagues Greg Laughlin and Fred Adams: (Astrophysics & Space Science, 275, 349-366, 2001)


Story Source:

The above story is based on materials provided by University of Sussex. Note: Materials may be edited for content and length.


Cite This Page:

University of Sussex. "Sun Will Vaporize Earth Unless We Can Change Our Orbit." ScienceDaily. ScienceDaily, 24 February 2008. <www.sciencedaily.com/releases/2008/02/080223130020.htm>.
University of Sussex. (2008, February 24). Sun Will Vaporize Earth Unless We Can Change Our Orbit. ScienceDaily. Retrieved January 31, 2015 from www.sciencedaily.com/releases/2008/02/080223130020.htm
University of Sussex. "Sun Will Vaporize Earth Unless We Can Change Our Orbit." ScienceDaily. www.sciencedaily.com/releases/2008/02/080223130020.htm (accessed January 31, 2015).

Share This


More From ScienceDaily



More Space & Time News

Saturday, January 31, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Video Shows Stars If They Were as Close to Earth as Sun

Video Shows Stars If They Were as Close to Earth as Sun

Buzz60 (Jan. 30, 2015) Russia&apos;s space agency created a video that shows what our sky would look like with different star if they were as close as our sun. Patrick Jones (@Patrick_E_Jones) walks us through the cool video. Video provided by Buzz60
Powered by NewsLook.com
Dog-Loving Astronaut Wins Best Photo of 2015

Dog-Loving Astronaut Wins Best Photo of 2015

Buzz60 (Jan. 30, 2015) Retired astronaut and television host, Leland Melvin, snuck his dogs into the NASA studio so they could be in his official photo. As Mara Montalbano (@maramontalbano) shows us, the secret is out. Video provided by Buzz60
Powered by NewsLook.com
NASA Holds Memorial to Remember Astronauts

NASA Holds Memorial to Remember Astronauts

AP (Jan. 29, 2015) NASA is remembering 17 astronauts who were killed in the line of duty and dozens more who have died since the agency&apos;s beginning. A remembrance ceremony was held Thursday at NASA&apos;s Marshall Space Flight Center in Alabama. (Jan. 29) Video provided by AP
Powered by NewsLook.com
Asteroid's Moon Spotted During Earth Flyby

Asteroid's Moon Spotted During Earth Flyby

Rumble (Jan. 27, 2015) Scientists working with NASA&apos;s Deep Space Network antenna at Goldstone, California discovered an unexpected moon while observing asteroid 2004 BL86 during its recent flyby past Earth. Credit to &apos;NASA JPL&apos;. Video provided by Rumble
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins