Satellite's gravity-mapping mission is over, ESA says

Oct 21, 2013
Undated artists impression of the Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite which is planned to lift off from Plesetsk on March 16, 2009.

A satellite measuring Earth's gravity since 2009 ran out of fuel Monday and will reenter the atmosphere within three weeks, when it will mostly disintegrate, the European Space Agency said.

Experts have said there will be little risk to humans when about 40 to 50 surviving fragments of the Gravity Ocean Circulation Explorer (GOCE) satellite hit our planet, though where and when this will happen is not yet known.

"The GOCE satellite has run out of and the end of mission has been declared," said an ESA statement.

The one-tonne satellite's stock of 41 kilograms (90 pounds) of fuel finally ran out at about 0320 GMT, GOCE mission manager Rune Floberghagen told AFP.

"We think it will take no less than two weeks, and no more than three weeks" for the satellite to reenter Earth's atmosphere.

GOCE was launched into orbit in March 2009 at an altitude of 260 kilometres (160 miles)—later lowered to 224 km—the lowest ever for a research satellite.

The 350-million-euro ($465-million) mission has lasted twice as long as its initially-scheduled 20 months.

Having now run out of fuel to keep it in orbit, the satellite will lose altitude and become unstable.

Its main gravity-mapping instrument has stopped working, but other gauges will continue gathering data for about two more weeks, according to Floberghagen.

Most of the 5.3-metre-long (17.2-foot) spacecraft will break up at an altitude of about 80 kilometres (50 miles), ESA spacecraft operations manager Christoph Steiger said last week.

But about a quarter of its mass, some 250 kilogrammes (550 pounds), will survive—hitting the Earths' surface in a trail of fragments over an area of a few hundred kilometres. Whether this will be on land or sea is not yet known.

"A few hours before, we will be able to tell with... a few thousand kilometres of precision" where the fragments are likely to impact, said Steiger—insisting the chances of a human being hit were about 65,000 times lower than getting struck by lightning.

In 50 years of spaceflight, there have been no casualties from manmade , despite about 20-40 tonnes impacting somewhere on Earth each year, said Steiger.

Scientists say GOCE has returned the most accurate data yet on Earth's gravity field and .

It was designed and built before 2008, when international recommendations were adopted that a scientific satellite must be able to execute a controlled reentry, or burn up completely after its mission.

Steiger said a global space debris coordinating committee was monitoring the to predict its point of reentry, "and we are passing on the information to national authorities.

Explore further: Out-of-fuel European satellite to come crashing down

add to favorites email to friend print save as pdf

Related Stories

'Ferrari of space' set to fall to Earth

Sep 12, 2013

A science satellite dubbed the "Ferrari of space" for its sleek, finned looks will shortly run out of fuel and fall to Earth after a successful mission, the European Space Agency (ESA) says.

GOCE's second mission improving gravity map

Nov 16, 2012

(Phys.org)—ESA's GOCE gravity satellite has already delivered the most accurate gravity map of Earth, but its orbit is now being lowered in order to obtain even better results.

GOCE's 'heart' starts beating

Apr 08, 2009

GOCE's highly sensitive gradiometer instrument has been switched on and is producing data. Forming the heart of GOCE, the gradiometer is specifically designed to measure Earth's gravity field with unprecedented ...

European science satellite hit by glitch

Aug 23, 2010

A satellite designed to map Earth's gravitational field has been hit by a software glitch and is unable to send its science data back home, the European Space Agency (ESA) said on Monday.

Recommended for you

NASA's space station Robonaut finally getting legs

4 hours ago

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...

Sun emits a mid-level solar flare

Apr 18, 2014

The sun emitted a mid-level solar flare, peaking at 9:03 a.m. EDT on April 18, 2014, and NASA's Solar Dynamics Observatory captured images of the event. Solar flares are powerful bursts of radiation. Harmful ...

Impact glass stores biodata for millions of years

Apr 18, 2014

(Phys.org) —Bits of plant life encapsulated in molten glass by asteroid and comet impacts millions of years ago give geologists information about climate and life forms on the ancient Earth. Scientists ...

The importance of plumes

Apr 18, 2014

The Hubble Space Telescope is famous for finding black holes. It can pick out thousands of galaxies in a patch of sky the size of a thumbprint. The most powerful space telescope ever built, the Hubble provided ...

User comments : 0

More news stories

NASA's space station Robonaut finally getting legs

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...

Cosmologists weigh cosmic filaments and voids

(Phys.org) —Cosmologists have established that much of the stuff of the universe is made of dark matter, a mysterious, invisible substance that can't be directly detected but which exerts a gravitational ...

Ex-Apple chief plans mobile phone for India

Former Apple chief executive John Sculley, whose marketing skills helped bring the personal computer to desktops worldwide, says he plans to launch a mobile phone in India to exploit its still largely untapped ...

Filipino tests negative for Middle East virus

A Filipino nurse who tested positive for the Middle East virus has been found free of infection in a subsequent examination after he returned home, Philippine health officials said Saturday.

Egypt archaeologists find ancient writer's tomb

Egypt's minister of antiquities says a team of Spanish archaeologists has discovered two tombs in the southern part of the country, one of them belonging to a writer and containing a trove of artifacts including reed pens ...

Airbnb rental site raises $450 mn

Online lodging listings website Airbnb inked a $450 million funding deal with investors led by TPG, a source close to the matter said Friday.