By Zbigniew Koziol

Eros - is not only a name of the Greek god of love, son of Mercury and Venus. On Aug. 13, 1898, Gustav Witt, director of the Urania Observatory in Berlin, discovered on the sky a new asteroid and gave it that ancient mythological name. The same day, it was independently observed by Auguste H.P. Charlois in Nice, France. Eros is now known as one of the closest to Earth asteroids in Solar System and the second largest.

It's relatively large size and closeness to Earth helped astronomers in determining precise distance between Earth and Sun and in measuring the mass of Earth-Moon system. The asteroid closest approach to Earth was observed on January 23, 1975. At that time, a large international research was performed, with participation of a team of Polish astronomers. Then, 25 years ago, the decision was made to send a spacecraft to that astral body in order to perform deeper investigation of its physical properties. The outcome of that research is supposed to throw more light on origins of Solar System, since the matter there must posses properties similar to these during its formation.

A space probe NEAR was actually launched four years ago, as a project managed by The Johns Hopkins University, Applied Physics Laboratory in Laurel, Maryland. Right now, NEAR after gradually descending tighter to this space rock, orbits on a distance of 100 km only from its surface.

Scientists are planning to turn on additional NEAR instruments: a laser scanner to help calculate Eros' exact shape and a spectrometer to determine its chemical composition. Other onboard instruments are measuring density and magnetic fields.

In the next step, at the end of this year, an attempt will be made to perform a controllable fall down of the craft onto the surface of Eros. The task is risky but would allow to carry on additional experiments. Eros has a low mass and its gravitational forces are very week - that's why this unusual operation is planned. However, irregular, patato-like shape of asteroid (see the picture above, courtesy of Jet Propulsion Laboratory, NASA) makes the landing operation dangerous - if a small mistake is made, the space craft could smack into the asteroid or get flung out into deep space and lost for ever.