What's that very bright star (south-oriented, appearing at 5 p.m.)? From my home I can see a very bright star (or a planet ?), appearing before 5pm local time, when I look toward South. It's really much more brighter than any other star, it's very often the only one you can see because of ambient light in the neighbourhood. It's even visible when it's a little bit cloudy.

Details:

My Location: N 50° 43.640' E 005° 41.430' (East of Belgium)
Time : 5pm (4pm UTC), December 21st, 2016
Direction : Almost straight on South (190°)
Altitude : 35°


Note that angles are rough estimates.

So, what's that star ?
That star is probably the planet Venus.

It is always close to the Sun, and Stellarium shows it to be in the south and well above the horizon at around 5pm local time.

To check, right above it should be Mars (also a planet).

In general, if you see a very bright star, it is very likely that it is a planet, and most likely to be Venus, Mars, or Jupiter. The latter two can appear at any time during the night, but Venus is always close to the Sun, so it can be seen just after sunset or right before sunrise. All planets appear close to the track of the Sun across the sky.