Ten questions added this time.
1) What size asteroid would cause a mass extinction ?
A large mountain.
2) Is there anything that could stop a planet from orbiting its star ?
None worth worrying about.
3) Why do we use the Roman names for the planets instead of the Greek ?
Because those idiot Greeks forgot to conquer Europe.
4) Can we see an object after it crosses the event horizon of a black hole ?
5) What are the first extraterrestrials we discover likely to be like ?
Pinky-purple with hats for feet.
6) If space is flat, can we travel into another dimension ?
7) When we measure the Cosmic Microwave Background, does the telescope have to point away from the Galaxy ?
No, but it's better that way.
8) Are planets born in planetary nurseries ?
9) Why do stars born in stellar nurseries have similar compositions ?
Because gas clouds are pretty boring places who don't like variety.
10) Do supernovae influence planet formation ?
Not directly, but they do influence star formation.