Friday, April 01, 2011

GOCE shows what Earth would look like if all gravity were created equal Read more: http://www.news.com.au/technology/sci-tech/goce-shows-what-earth-w

GOCE geoid

ESA's staellite (right) has delivered the most accurate model of the "geoid" ever produced. Credit: ESA

AFTER nearly two years in space, the European satellite GOCE has collected the raw data needed to map variations in Earth's gravity field.

The data will help scientists better understand the impact of climate change on sea levels, ice sheets, and ocean circulation systems.

More importantly, it's also helped them create this alternate version of what the Earth would look like if gravity exerted an even pull across the entire planet.

As it stands, Earth's slightly flattened shape and the irregular distribution of heavy rock leads to inconsistent gravitational forces across different regions.

Scientists at ESA have used the new data to generate this planetary "geoid", a model of what they say is an "ideal planetary ocean".

ESA launched the 5m long, 1050kg satellite in 2009 as part of its "Earth Explorer" programme.


From its relatively low orbital position 260km above the planet, GOCE can detect minute changes in Earth's gravity field, something in the order of one part in ten million million.

Why?

Because scientists say the geoid will allow for a far more accurate measure of ocean circulation, massive ice sheet in Greenland and Antarctica and changes in sea level, all of which are influenced by global warming.

An improved knowledge of gravitational discrepancies will also contribute to a clearer view of Earth's interior, as well as the physics behind volcanoes and earthquakes.

GOCE (Gravity field and steady-state Ocean Circulation Explorer) is slated to continue its mission until the end of 2012.

- with AFP



Read more: http://www.news.com.au/technology/sci-tech/goce-shows-what-earth-would-look-like-if-all-gravity-were-created-equal/story-fn5fsgyc-1226031866464#ixzz1IEvaNBAG

No comments: