Nasa probe strikes comet
Jubilation at NASA's Jet Propulsion Labs in California, as the first picture of the collision comes in from the Deep Impact mother ship. Just before six o clock GMT, the impactor, weighing a third of a ton, smashed into Comet Tempel 1 at a speed of thirty seven thousand kilometres an hour.
Telescopes across the world, and in Earth orbit, will be watching the giant spray of debris thrown out by the impact. The brightened comet in the constellation Virgo may even be visible to the naked eye, allowing members of the public around the world to join in this historic moment in astronomy.
The next twenty four hours could change our understanding of how the solar system formed, as pristine material from inside the comet is revealed for the first time in four and a half billion years.
Jubilation
joyful celebration
Propulsion
pushing forward
collision
impact
mother ship
the ship carrying the projectile
impactor
projectile, probe
the giant spray of debris
the massive flow of scattered fragments
constellation
a number of stars seen from the Earth as a group and often having a name
to the naked eye
without any instrument to help you see
to join in
to share
pristine
untouched, unspoilt