The Telescope is a block added by Astral Sorcery. It is used to discover bright and dim Constellations, provided that the appropriate Constellation Papers have been acquired. It functions similarly to the Looking Glass; right-clicking the placed block at night will show a view of the night sky's stars, among which the stars of constellations stand out. Unlike the Looking Glass, the Telescope allows players to draw Constellations immediately; The GUI has arrows on the side that rotates the angle of the telescope to 4 different views of the sky.
There must be no opaque blocks above or directly next to the telescope.
The Looking Glass was all good and fine, but holding still all the time is exhausting and doesn't give a good view. It is also difficult to make out more than one Constellation at a time in one night, so discovering everything those Constellation Papers show would take forever.
The telescope will need a fixture for this. That way, it should be possible to look deeper into the sky, finding stars and Constellations that are even further away in a much easier fashion.
Discovering Constellations is nearly the same as with the Looking Glass, a clear view to the night sky without obstruction is required.
It's only possible to look at one section of the sky at a time, but rotating the telescope's facing with the arrows on the left and right shifts the field of view. Drawing outside the telescope frame or rotating the telescope erases all drawn lines.
Hints of new kinds of Constellations seen within the telescope now appear that are more Dim, and further away, than the major Bright Constellations. Attuning to them may not be possible, but there should still be enough Starlight to create crystals that focus that light.
Attuning yourself should make it easier to track and trace these Dim Constellations.