Wow, I've just noticed a load of asteroids appearing in KSP's space center. My first thought isn't "What if they hit Kerbin and wipe out the entire Kerbal race?". It's "How much science can I get from them?"
Can I get science from asteroids?
Just like any other experiment part (since Asteroids, too, are just parts), you can dock with the Asteroid using the Claw and then take a sample of it.
Just like other experiments, the result depends on the current location of your craft (altitude, sphere of influence, orbital parameters) with each such situation for each asteroid individually (unlike other experiments) yielding 60 Science.