ESA's satellite sends data for development of best gravity map ever

Paris, October 1 (ANI): Reports indicate that the European Space Agency's (ESA's) GOCE (Gravity field and steady-state Ocean Circulation Explorer) has started sending data that will lead to the development of the best gravity map ever, providing a better understanding of Earth's gravity.

The GOCE satellite was launched on March 17 from northern Russia.

It is often assumed that gravity exerts an equal force everywhere on Earth.

However, owing to factors such as the rotation of the planet, the effects of mountains and ocean trenches, and density variations in Earth's interior, this fundamental force is not quite the same all over. Over two six-month uninterrupted periods, GOCE will map these subtle variations with extreme detail and accuracy.

This will result in a unique model of the 'geoid' - the surface of an ideal global ocean at rest.

A precise knowledge of the geoid is crucial for accurate measurement of ocean circulation and sea-level change, both of which are influenced by climate.

The data from GOCE are also much-needed to understand the processes occurring inside Earth.

In addition, by providing a global reference to compare heights anywhere in the world, the GOCE-derived geoid will be used for practical applications in areas such as surveying and levelling.

A little over six months after launch, GOCE is now delivering the first set of data that will build into the most detailed map of Earth's gravity field ever realised.

Before entering this mode, the satellite was tested thoroughly. It was then gently brought down from an altitude of around 280 km to its current orbit slightly below 255 km, which is extremely low for an Earth observation satellite.

It turns out there is very little solar activity at the moment, which means a calmer environment for GOCE.

So, its current orbit of 255 km is a few kilometres lower than engineers had originally planned.

This is good news as the gravity measurements being made at the moment will be even more accurate.

According to Rune Floberghagen, ESA's GOCE Mission Manager, "The completion of the commissioning and first in-flight calibration marks an important milestone for the mission. We are now entering science operations and are looking forward to receiving and processing excellent three-dimensional information on the structure of Earth's gravity field." (ANI)