A person who studies planets and galaxies is called an astronomer. Is that the answer you were looking for?
Hundreds of billions of stars, some of them with planets.
It makes sense to talk about the climate on other planets, not on other galaxies. Not much is known about the climate on any planet outside the Solar System.
Galaxies are formed by stars, planets, comets, meteors, and other space bodies.Stars have their own source of energy, tones of hydrogen burned into hellyum every second, while planets don't have, and get heat from the nearest star. Stars are the furnace of the universe eventually allowing planets to develop life, like the Earth.
About 30.
At its centre.
Ultraviolet
The path of univers's galaxys
the reason why astronomy was started is that when the astronauts wnet up and found moon rocks new planets, new galaxys they needed people to study them so they could gain further knowledge on what exists in this universe (i think :P)
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the milky wayis the galaxy that our sun is in
Itouch defiantly.