Differences
1.An astroid is more rough an bumpy while the comet is a small bit smoother,
2.A comet is more likely to be able to see while astroids you are not able to see,
3.A astroid is more likely to come more than comets.
Same
1.Comets and astroids are from outer space
2.Astroids and comets are very easy to see with a telescope
3. Astroids and comets are part of the solar system
I hope I helped