Edwin Hubble found out that what appeared to be large clouds in space were not gas, but _

A: galaxies
B: the Oort cloud
C: comets
D: large stars

I believe they were the Oort Cloud

Explanation:

this idea is similar to nebulas and similar space features.

i also need this answer for on a project, does anyone know the answer? ?

the answer is: they occur when the sun, moon, and earth are aligned. in spite of their name, these tides occur twice a year in the spring and fall.