Compared with its dazzling neighbour Orion, Taurus (the Bull) is very much the second cousin when it comes to the glitter stakes. But it has distinguished roots, dating back to Babylonian times.
In legend, Taurus is Orion’s adversary. With his two dogs – Canis Major and Canis Minor – the mighty hunter pursues the Bull across the sky in perpetuity.
Baleful red Aldebaran marks the Bull’s eye. Some 65 light years away, it’s the 14th brightest star in the sky, and is 400 times larger than the sun. Like nearby Betelgeuse, Aldebaran is a red giant: it has consumed its hydrogen fuel, heated up internally, and billowed out in its late middle age. It’s downhill from now on.
The Bull’s V-shaped head is marked by the Hyades star cluster. At 153 light years distant, it’s the closest star cluster to Earth, and its stars have been intensively studied. It’s made up of hundreds of stars, celestial siblings born 625 million years ago.
The Hyades holds a unique place in astronomy. Its stars have been so carefully scrutinised that astronomers know its distance with incredible precision. We can recognise similar star clusters which are more remote, and work out how much further away they lie. This means that the Hyades stars are the first rung on the cosmic distance scale: a ladder that takes us from the familiarity of our local neighbourhood out to the dark recesses of the furthest galaxies.
Alas, in beauty the Hyades can’t hold a candle to the glorious Pleiades, the other major star cluster in Taurus. This sparkling, jewel-like group of stars is part of many of the world’s cultures. Despite their popular name, the “Seven Sisters” are anything but. When you ask people how many Pleiads they can see, the answer is normally six. But some sharp-eyed observers have spotted 11, and the record has gone down as 14.
Telescopes reveal that the total number of Pleiads runs to about 1,000 stars. These are all infants on the astronomical scale – at 75 to 150 million years old, a little younger than the Hyades – and are burning incandescent blue-white in their youth. The cluster is further away than the Hyades, and astronomers are currently divided about its distance: the best money is 444 light years
You’ll see images of the Pleiades wreathed in glowing dust, reflecting the stars’ light. Originally, researchers thought that this was leftover dust from the cluster’s formation; but they now think that the Pleiades have cannoned into a dust cloud as its stars move through space.
The stars themselves are all young, hot and vigorous – a gorgeous sight for the unaided eye, binoculars, or a telescope. One of the Plieads may be busy making planets.
But the Pleiades won’t last forever. The cluster will gradually unravel as its individual stars pursue their own orbits through the galaxy, There’s a bit of a way to go, however – like another 250 million years.
Finally – to Taurus’s best-kept secret. The Bull has two “horns”: the star EI Nath (Arabic for “the butting one”), and below it Zeta Tauri (whose Babylonian name is Shurnarkabtishashutu).
If you observe this star with a moderate-to-large telescope, you’ll see only what can be described as a cosmic mess nearby. This is the tangled shape of the Crab Nebula: the wreck of a star that blew itself apart. Chinese astronomers witnessed the explosion in 1054, and recorded that it was visible in daylight for 23 days, and remained in the night sky for two more years.
Only youthful stars more than eight times heavier than the sun are doomed to their death in a supernova like this. Console yourself with the fact that the sun is just a middle-aged, middle-class star – and it won’t go out with a bang. .
We have a Christmas Star! You can’t miss brilliant Venus low in the southwest after sunset, hanging like a glorious lantern in the darkening sky. To its lower right lies Jupiter, the second brightest planet; but this giant world sinks down below the horizon during December.
The Evening Star is moving upwards, towards Saturn, and passes under it on 10 and 11 December. Venus outdazzles the ring-world, shining almost 100 times brighter than Saturn. There’s a lovely sight on 28 and 29 December, when a narrow crescent moon hangs right next to Venus.
The opposite side of the sky, towards east, is bespangled by the glittering jewels of the winter heavens. Most distinctive is Orion, the mighty hunter, with three stars forming his belt, and Taurus to his upper right. High above is Capella, the brightest star of Auriga (the Charioteer). And to the upper left of Orion you can spot the twin stars of Gemini, Castor and Pollux.
Around the middle of December we’re due for a shower of shooting stars streaming out from this region of the sky. These Geminid meteors are dust from an asteroid, called Phaethon, burning up the Earth’s atmosphere. They are one of the most spectacular meteor showers of the year, but this month all but the brightest will be washed out by bright moonlight.
The new moon on Boxing Day passes right in front of the sun, leaving a bright ring of the solar surface visible around its silhouette. Unfortunately, you’ll have to travel to the Middle East, the Indian Ocean or Indonesia to view it.
10 December: Venus near Saturn; moon near Pleiades and Hyades
11 December: Venus near Saturn
12 December, 5.12am: full moon
13-14 December: maximum of Geminid meteor shower
14-15 December: maximum of Geminid meteor shower
16 December: moon near Regulus
19 December, 4.57am: last quarter moon
20 December: moon near Spica
22 December, 4.19am: winter solstice
26 December, 5.13am: new moon; annular solar eclipse
28 December: crescent moon near Venus
29 December: crescent moon near Venus
‘Philip’s 2020 Stargazing’ (Philip’s £6.99) by Heather Couper and Nigel Henbest reveals everything that’s going on in the sky next year.
Fully illustrated, Heather and Nigel’s ‘The Universe Explained’ (Firefly, £16.99) is packed with 185 of the questions that people ask about the Cosmos.