Some of these need a properly dark sky and eyes that have had twenty minutes to adjust — which is the single most-skipped step in astronomy. The Sun is here only by projection or through a proper solar filter: never look at it directly.
Binoculars held steady against a fence reach all of these — and so does any telescope. This is where the surprises live: Saturn as an oval, Jupiter’s moons rearranging themselves overnight, and the Orion Nebula resolving from a smudge into a shape.
A 150 mm telescope is one whose mirror is 150 mm (six inches) across. These are hard: dark sky, no Moon, and knowing exactly where to point.
The Earth goes round the Sun, so the night side faces a different direction in each season. That is the whole reason some things are “winter objects” (the seasons here are the northern ones; south of the equator, swap winter for summer):
Colour, mostly. And the arms of galaxies, and the shapes in the famous photographs. Those pictures are hours of exposure through telescopes the size of a house, and colour that your eye cannot collect at low light. The eyepiece views on this site are drawn as things really look through a small telescope, on purpose, so that what you find outside is a surprise rather than a disappointment.