A telescope
telescopes of course
There are comets all the time, sometimes we can see them with the naked eye.
snowballs
To see planets, stars, comets and to take pictures.
TELESCOPE
See related link for a list of periodic and non periodic comets.
They are. We generally first see comets as they approach the Sun and become visible; if the comet survives the near approach to the Sun, we can continue to see them as they move away from the Sun. Depending on the comet's orbit as compared to the Earth's, we sometimes can't see the comet very well until after it is already moving away from the Sun. And of course, the first three comets discovered in 2010 were all discovered by satellites watching the Sun - as the comets fell INTO the Sun.
when your balls drop
That's a description sometimes given to comets.
Because there aren't always comets!
Yes, because comets are so tiny and dim.
Comets travel in highly elliptical orbits. See link for more.
No. Planets do not have comets. They are not related to planets. They are just objects flying through space that we can see in the sky.