Starwatch: Night sky gets scary in time for Halloween

Diagram A: of the Constellation Perseus the Hero with the Pleiades nearby

If air traffic control is busy next week, it will be more than just ghosts, goblins, ladies in black riding brooms, and possible Halloween drones. Higher up in the heavens there will be a lot of action as well.

First of all, we have the famous, or some would say infamous, Pleiades star cluster, also known as the "Seven Little Sisters." This time of year it's also referred to as the "Halloween Cluster" because it rises in the northeast early in the evening and climbs high in the sky around midnight.

You can't miss it, as it's easily visible to the naked eye, resembling a miniature Big Dipper. Astronomically the Pleiades is actually a group of over 100 young stars, more than 410 light years away, that were born together out of a huge cloud of hydrogen gas 100 million years ago.

Many ancient peoples worshiped and feared the Pleiades because the cluster was associated with death. When it rose high in the sky around midnight this time of year, it was thought to be the appropriate time to honor the dead. Some cultures, like the early Egyptians, believed that whenever the Pleiades reached their zenith in the sky, natural disasters as well as manufactured ones like war could more easily occur.

Snakes alive!


Probably the most sinister constellation on the rise is just above and to the left of the Pleiades, Perseus the Hero. Now, Perseus himself is not all that scary, but it's the monster's head he's toting with him, the evil Medusa, that gives me the shivers. According to Greek and Roman mythology, Perseus was dispatched by Zeus, the king of the gods, to rid the countryside of Medusa, a lady monster who was literally stoning the countryside.

Medusa was truly one of most horrible monsters you ever saw. In fact, you couldn't even look at this beast with a female face, because her hair consisted of dozens of poisonous snakes. Medusa was so ugly that if you even took a brief glance at her you would instantly turn to stone.

Medusa had to be stopped before all of humanity became stone cold. Perseus went in pursuit of the horrible monster. Armed with the wings of Mercury, the messenger of the gods, and the magic shield of Athena, the goddess of wisdom, he managed to kill Medusa by slicing off her snake ridden head with his razor sword without actually looking at it himself. Don't ask me how he pulled that off. It must have been Athena's magical shield.

Star power

To honor Perseus, the gods and goddesses placed his body in the stars as the constellation we see rising this Halloween week. With a little imagination, you can kind of see a crooked stickman about halfway between the horizon and the overhead zenith in the northeastern skies. The Pleiades are just off his feet.

As you look at the constellation be careful, however, because he's still holding up Medusa's severed head, marked by the fair bright star Algol. Be extra careful looking at that star. I want you around to eat that Halloween candy that's left over around your house.

Algol is also known as the "Demon Star" because it actually blinks as it dims in brightness. It's certainly not a strobe light because it only dims about every three days and stays dim for about nine hours before it brightens up again. Astronomically it's known as an eclipsing binary variable star. It's actually a three star system, but two of the larger stars are eclipsing each other in their nearly three-day orbit around each other.

Taurids coming


There's also a minor meteor shower starting up later this haunted week called the Taurids. They actually peak out in early November, but they're getting going this week.

The Earth, in its path around the sun, is running into a fairly sparse debris trail left behind by Comet Encke. Most of this debris is no bigger than pebble size, but when they slam into our atmosphere at over 65,000 mph, they really light up the sky. You probably won't see many of them while you're taking the kids out trick or treating though. They're best seen after midnight, originating from the constellation Taurus the Bull, but be careful after midnight because that's when it can really get spooky around Halloween!

Also during this Halloween week we'll have a growing crescent moon in the western sky as darkness sets that will add to the spooky ambiance of the week. By Halloween night on Friday, however, the first quarter half moon will help light your way with all the haunting going on. Have fun and stay safe!

Celestial hugging

Mars and the new crescent moon will be close together this coming Monday and Tuesday evening in the low southwest sky toward the end of evening twilight.

Diagram B (optional) Mars and the crescent moon Monday and Tuesday evening

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