BBC Homepage World Service Education
BBC Homepagelow graphics version | feedback | help
BBC News Online
 You are in: Sci/Tech
Front Page 
UK Politics 
Talking Point 
In Depth 

Monday, 12 February, 2001, 22:13 GMT
Probing the secrets of Eros
Near-Shoemaker will soon run out of power
By BBC News Online science editor Dr David Whitehouse

Asteroid Eros joins the Moon, Venus and Mars as celestial objects touched by a man-made craft.

Although probes have flown through the tails of comets and even descended into the atmosphere of Jupiter, the Near Shoemaker spacecraft has revealed to us what is perhaps the strangest world ever encountered.

NASA Eros surface detail
Near Shoemaker had a clear view of the asteroid
As it came closer and closer to the 21-mile (33.6km) long, nine mile (14.5km) wide rock, Near Shoemaker's close views showed just how strange and little-understood Eros is.

Everywhere is covered in a layer of fine dust. From a distance, and when shadows are long and the surface relief is prominent, ancient "ghost" craters can be seen, mostly buried underneath the dust layer. Boulders, surrounded by curious "aprons" of debris, also protrude through the dust.

Mysteries remain

No one knows why the surface is covered in dust this way. Perhaps when Eros has been struck by smaller chunks of rock, seismic shockwaves ripple through it causing dust to be dislodged and to "flow" downhill behaving like water.

On a smooth plain, with the Sun a bright point of light almost on the horizon of this strange world, Near gently touched the surface - probably throwing up a shower of dust and rebounding a few metres.

If the scientists had expected to lose contact with the craft, they were wrong.

A signal, albeit at reduced strength, continued to struggle out towards Earth. No one knows how long it will last.


So mankind now has a working science station on one of the multitude of tiny worlds that circle the Sun between the orbit of Mars and Jupiter.

The pictures taken by Near Shoemaker as it descended to the surface of this primordial world will no doubt reveal many of its secrets, especially of its birth when the Solar System was young.

Some day, one of these chunks of rock in space may head for the Earth and threaten us with extinction as one of its cousins did to the dinosaurs.

But Near Shoemaker's triumph has forever demystified the objects. Now, they do not seem so menacing.

The tiny probe's batteries will soon fade, as the dust-streaked solar panels fail to provide power and Near Shoemaker will soon die.

Together it and Eros will circle the Sun, almost forever.

Search BBC News Online

Advanced search options
Launch console
Links to more Sci/Tech stories are at the foot of the page.

E-mail this story to a friend

Links to more Sci/Tech stories