That one is called the eyepiece, and the other one
is called the declination setting circle.
A spyglass or a telescope.
It is the one kind of telescope use in space. The Hubble Space telescope, is the one of the most common used-technology in space. The Hubble Space telescope was named after Edwin Hubble.
a telescope.
It was called a "Spyglass". Or, it was also called a telescope.
That telescope you are refering to is called a refracting telescope.
There are not synonyms for nouns. Nouns do not have synonyms. The closest thing to telescope would probably be eyeglass.
It is called a refracting telescope.
the hubble telescope
It gathers more light than a refractor type of telescope can, of the same size.
A spyglass
Hubble space telescope and international space station!
Usually it's simply called a "solar telescope, but there are other names such as "helioscope" (specialising in sunspot observation).