It's been a memorable week for astronomers. Last Saturday NASA's Deep Space 1 survived a treacherous venture into the halo of dust surrounding Comet Borrelly and captured over thirty images of it's icy nucleus. This is only the second time a comet has been observed from close up - the first time being when Halley's comet appeared in 1986. The new images reveal what looks like an "eerie cosmic potato" - an icy pockmarked landscape with weird jets of gas escaping from the surface. The biggest surprise is that the comet's 5 mile long nucleus is not where we expect it to be - it is off-centre. The images come as a real bonus to astronomers - few people expected Deep Space 1 to survive the encounter since it had absolutely no shielding against comet's dust halo. NASA scientists are ecstatic and say our knowledge of comets has doubled overnight.