Phycisists said:
Ok, thanks! But how do I know the location of the space stuff?
By the way, just to be clear regarding the planets, you should be able to Venus, Mars, Jupiter and Saturn (and even Mercury if you catch it at the right time of its orbit) with your naked eyes alone -- no binoculars or telescope required.
This of course assumes that it's not cloudy, and the planet in question is presently on this side of the night sky. If the planet you are looking for is not on this side of the sky at the moment, it probably will be eventually if you wait until morning (unless its angular position is right next to the Sun). Planets rise and set just like the moon and the Sun (well, almost "just like." 'Slightly different timing, but only slightly).
You should be able to see the planets with your naked eye even in the most light-polluted cities in the world. These planets are
really bright (compared to other celestial objects besides the Sun and Moon).
The easiest way to spot them if you don't know what to look for, and if you have a smart phone, is to download an app such as Google Sky Map (for Android -- there are other, similar apps for the iPhone). Just point your smartphone at the sky, and it shows you what's what.
Another option is to use a astronomy, computer program like davenn mentioned.
Baring those, here is some general advice:
- Planets do not twinkle like stars do. If you see a stationary, star-like thing but it's not twinkling like the rest (and it's on the ecliptic -- see below), it's likely a planet. The reason stars twinkle is because even with huge optical telescopes with incredible magnification, they still appear very point like, and are thus subject to even the tiniest atmospheric aberrations, as the light passes through the Earth's atmosphere. Planets on the other hand, although subject to the same atmospheric aberrations, have a much larger angular size, from our perceptive. By that I mean when viewed with a telescope, the planet looks like a disk, not a point. So when viewed with the naked eye, the atmospheric aberrations tend to be averaged across the disk, eliminating the "twinkle."
- Planets follow a path along what is called the ecliptic. This is the same general path through the sky the Sun moves through. The ecliptic extends more-or-less from East to West and is tilted toward the South, since you are in the Northern hemisphere. The amount of "tilt" also depends on the time of year. The ecliptic will extend higher in the night sky during the winter months and lower (more toward the South) in the summer months. (That's related to, yet effectively opposite, the reason the sun is higher in the sky during the summer and lower in the sky during the winter.)
- Venus and Mercury (especially Mercury) will never stray too far from the Sun. Venus will always be either in the West after sunset or in the East before sunrise. For example, you will never see Venus in the East just after sunset. The same applies to Mercury, but to a greater extent. It's actually pretty tough to spot Mercury only because it is always so close to the Sun.
By all that, I mean to say that you don't need a telescope or binoculars to see the planets and figure out where they are. [Edit: Except for Uranus and Neptune -- you'll need binoculars or a telescope for those. But the rest you should be able to spot with the naked eye.]
But a telescope, even a small, inexpensive telescope,
can allow you to see details on the planets, such as the four Galilean moons of Jupiter, the rings of Saturn, the phases of Venus (yes, Venus has phases, not dissimilar to that of our Moon), possibly ice caps on Mars (don't hold your breath on that, but if you catch Mars at opposition you might have a good chance), and the craters on the Moon.
[Edit: and since you have a comparatively high latitude in Gothenburg, Sweden, the ecliptic will be tilted quite a bit to the South. So, when planet hunting, pick a location that doesn't have a lot of obstructions (trees, buildings, etc.) when looking South.]
