The Moon and (most of) the planets are the brightest objects in the sky, and they are the first things to interest most people when they have access to a telescope. Because they are bright, we can run "Lunar and Planetary" observing nights in acessible locations without being greatly concerned about the amount of light pollution. Typically, we run one or two of these nights each year, coinciding with times when the best selection of planets are "up" at the one time (in the evening).
So what can we see of the planets ?
- The Moon, being by far the closest object to the Earth, provides the best opportunity to see the surface of another object - craters, mountains, mare...
- Jupiter and Saturn are always favourites, being big and bright whenever they are visible. Both have visible moons and cloud belts (particularly Jupiter) and of course Saturn has its spectacular ring system
- Mars is of considerable interest when it is close to the Earth - at opposition, roughly every 2 years - but most of the time it is a rather small, dim, orange dot.
- Venus is always bright, and through a telescope, you can see it has "phases", like the moon, but with its thick cloud cover, no detail can be seen apart from its shape
- Mercury never appears far from the sun, so it is hard to observe. It also shows phases like Venus, but they are less marked. Being not so very much bigger than the Moon, and much farther away, it is hard to see any surface detail
- Uranus and Neptune, the outermost (known) planets, never appear as more than small, bluish-green discs through amateur telescopes.
Keeping the observing site dark
We do not need to be particularly strict about white light on lunar and planetary nights, but we still want to keep it as dark as possible