Paris, Nov 14: Rosetta, the ESA's (European Space Agency) comet chaser, successfully swung by Earth on Novemeber 13, which was the scheduled date decided by astronomers for the passing by of the spacecraft.

The comet chaser flew directly above 63 DEG 46' south and 74 DEG 35' west, at 21:57 CET (above the Pacific ocean, south-west of Chile). It whizzed past 5295 km overhead, at a velocity of 45 000 km/h (12.5 km/s).

Around closest approach, Rosetta took a good look at Earth for observations of its atmosphere and magnetosphere, imaged urban regions, and looked for meteors from space.

Shortly before midnight, Rosetta will turn to observe the Moon at about 11:00 pm today. Following this, Rosetta will observe the Earth-Moon system from a distance on 15, 16, 18 and 20 November on its outbound trajectory.

Scientists are now eagerly awaiting some of the first data to become available during the course of the night.

This was Rosetta's second swing-by, speeding past at 45000 km/h relative to Earth. It will be followed by the third and last swing-by, on November 13, 2009.

Swing-bys like these make use of the gravitational attraction of planets to modify a spacecraft's trajectory and to gain the orbital energy needed to reach the final target.

Similarly, Rosetta is using the gravitational pull of the Earth to be catapulted towards the outer solar system with a newly gained energy.

The passage of the spacecraft would be through an asteroid belt in September 2008 to observe the asteroid Steins, which is one of its scientific targets.

The increased energy from this Earth swing-by will also help Rosetta cross the asteroid belt for a second time, observe Lutetia (its second target asteroid) and finally rendezvous with comet 67/P Churyumov-Gerasimenko. This rendezvous will take place about 4 astronomical units or 600 million km from the Sun in 2014.

Europe's comet chaser has now flown a little over three thousand million km of its 7.1 thousand-million-km journey on its way to its destination comet. (ANI)