NASA is shooting things at comets, just to see what happens

And they're naming their devices after cheesy disaster movies.

From their press release:

The Deep Impact spacecraft's 820-pound 'impactor' is scheduled to
smash into the Tempel 1 comet on July 4, Eastern Daylight Time (late
July 3, PDT). Scientists hope to learn more about comets by observing
the resulting cloud of debris following the impact. Scientists believe
the impact will form a crater on the comet.

Ames' Vertical Gun Range is used to simulate the physics and
mechanics of planetary 'impact cratering' and micrometeorite impacts.
For Deep Impact, studies included crater-scaling experiments.

The Vertical Gun has been used to conduct tests related to many other
space missions including Apollo, Mariner 9 to Mars, Mariner 10 to
Venus and numerous others.

Earlier: "It is not appropriate for the U.S. to not be the world's prime space-faring nation."