The Majestic Clockwork

There's something quite special happening in the evening sky at the moment, something to be shared with your children, grandchildren etc. If you want to observe clearly the movement of planets, do the following:-

At around 6pm, locate Venus. Look at an elevation of about 30 degrees above the western horizon. Venus will be easy to find. It is the second brightest natural object in the night sky; only the Moon is brighter. Having found Venus, observe that there's a bright object just below. That is the gas giant, Jupiter. Whilst it appears that the two planets are in close proximity, this is not the case. Our perspective from Earth makes them appear close. Jupiter is in the distant background to Venus, some 900,000,000 kilometres beyond (approximately).

If you've a good pair of binoculars and clear viewing conditions, you may be able to observe that Venus has phases, just like our Moon. It's in its crescent phase at the moment. You may also be able to see four of Jupiter's sixteen moons.

Now, here's the "wow" thing. Repeat the observations in about a month. Both planets will be lower in the western sky. The relative position of the two planets has clearly changed. They will be side-by-side, whereas before, they were one above the other. Venus is setting (getting closer to the western horizon). Jupiter is also setting, but because of the distance to it, its movements are not as pronounced. Having two bright objects to use as reference points makes the movement easily apparent.

FYI, the word "planet", of Greek origin, means "wanderer". The phrase "majestic clockwork" was coined to summarise the mathematics of planetary motion, discovered by Sir Isaac Newton.

Cheers for that Bristol. I will try to show the kids tonight.

Bloody clouds!

7 days ago they were aligned . first time in 2000 years . some were calling it the the star of Bethlehem. Read something online about it .. I didn't see it but apparently was very bright .