Hubble captures comet break-up
The Hubble space telescope, a joint project between the European Space Agency (ESA) and NASA, has captured amazing pictures of a comet disintegrating. The Hubble pictures have shown more comet particles on break-up than were seen from ground-based observatories, once again reaffirming Hubble's worth. The comet, 73P/Schwassmann-Wachmann 3, is disintegrating due to its close proximity to the Sun. The comet will pass the Earth on 12 May and then swing past the Sun on 7 June. The comet has now broken up into several pieces, all travelling on the same course. Hubble has been able to pick out the disintegration of the comet in detail. Chunks of comet have broken off the main nucleus, and those chunks have again broken up. For example, chunk B broke away, and has been pushed further and further down the comet's tail, breaking up as it goes. The smallest pieces are ejected the most quickly. ESA team member Philippe Lamy from Laboratoire d'Astrophysique de Marseille, France, said, 'When we observed the comet in late 2001 we concluded that many small, by then invisible, fragments had to be created by fragmentation to account for the missing mass. The new Hubble observations beautifully confirm and illustrate our past findings.' The pictures of 73P/Schwassmann-Wachmann 3 show that this comet, which orbits the sun every five years or so, may be reaching the end of its life, with fragmentation increasing. Comets meet their end for a variety of reasons - ripped apart by gravitational tidal forces - as happened to comet Shoemaker-Levy 9 when it skirted Jupiter in 1992, flying apart as the nucleus rotates rapidly, crumbling under thermal stresses as they pass near the Sun, or exploding as trapped volatile gases burst out.