Hey, hey, Sky Fans! Thanks for stopping by today on this the, Thursday of October’s World Space Week. If today’s the Thursday, that means this coming Saturday, October 8, is October’s Astronomy Day!
Astronomy Day happens twice a year, once in the spring, and once in the fall, and is a great opportunity to step outside and just look up. It’s all there. This time around, it’s also International Observe the Moon day. Maybe there are some events happening at your neighborhood planetarium, or with a local astronomy club. This is a great chance to meet up with other astronomy lovers, look thorough telescopes or pair of binoculars. Throw in a beer and some pizza and it sounds like paradise if you ask me.
If you don’t have a planetarium or astronomy club close to where you’ll be, and you’re no good with a telescope (believe me, I’m with you on that), you still have your naked eyes. It’s the way most of us get started with astronomy, and the more people I’m lucky enough to talk to, the more agree it’s also the way lots of us fall in love with it. I’m not sure where I’ll be on Saturday, but I imagine I’ll be standing outside with my wife and kids staring at the sky and talking as people walk quickly in the other direction. You know, we can be our own naked-eye astronomy club. What do you want to look at?
If you need a hand, here’s are a few things you can see and talk about with your friends if your skies are good Saturday. Of course, feel free to use lenses if you want. I’ll probably have a pair of binoculars with me, but these are all terrific with just your eye and your love of the sky.
Everything in this list will be out and about much of the night, kind of centered around mid-evening, maybe 9:00 or 10:00, say, though that’ll vary a little depending on where you are. I’ll let you know otherwise.
Kinda sorta in no particular order, away we go:
- The Sun moving across the sky
It is Astronomy DAY isn’t it? Why should everything we talk about be at night? So, when you have a minute a few times during the day, look at where the Sun is. In the morning, as you know, it’ll be in the southeast, and it’ll move across the southern sky until it sets in the southwest. Try to keep where it’s been in mind, and imagine where it’s going. That path it takes across the sky is called the ecliptic, and it’ll come in handy later on. Please please please, no telescopes or binoculars for this. At best, it’ll hurt, and at worst, you could severely damage your eyes. Do not stare at the Sun. Lenses or not, it’s a bad idea. I said please.
- The daytime Moon
You might not have thought about it, but the Moon spends just as much time above the horizon during the day as it does at night. Tonight’s phase, just before first quarter, with the right-hand side lit, rises around midday. So, by around 3:00pm it’ll be high enough in the afternoon blue to be easily seen over the treetops and buildings near your house. I love watching the Moon in the day. It’s like dessert before dinner. There are few things in astronomy that I find more inspiring than seeing the daytime part of the Moon etched into the sky, and nighttime side disappearing into the blue. Stop and stare for a minute. It’s worth it.
- Four of our nearest neighbors stretching across 50 degrees of the sky
As night falls, the planet Venus will appear. It’s making its way higher and more southward into the sky every day. You’ll need to look fairly early, not more than about a half hour after sunset, to see it on Saturday. It’ll be low in the sky, but unmistakably bright. As the night moves on, look for the Moon high in the south. You can use it to find the bright red dot that is the planet Mars a short way below and to its right. Between Mars and where Venus was before it set will be the planet Saturn, which I always love for how understated and subtle it is with the naked eye. I won’t lie; Saturn’s a little tough. It’s not as bright as you want it to be, but cut it some slack, it’s a billion miles away! Remember the path the Sun took in the afternoon, if you can, try to map that same path onto the night sky. The ecliptic will run pretty close to right through the three planets and help you find Saturn if you don’t see it right away. The bright star Antares will be directly below Saturn.
- The Moon as it was on July 21, 1969
When Apollo 11 astronauts Neil Armstrong and Buzz Aldrin shut down the Eagle’s engines, stepped outside, and became the first humans to walk on another world, the Moon was just before its first quarter phase, which is just about where it is Saturday. For those couple of hours, the full Moon phase stopped getting all the attention. With just a quick glance up, you can imagine or remember what it was like that night. Imagine watching them on TV, while, with just a turn of the neck, looking at the place where the most distant humans ever were. I’m too young to have seen any of it, but it’s amazing to think we, people who worked together to make it happen, left footprints there.
- The Sea of Tranqulity
As if just being able to see the Moon isn’t enough, you can see where Apollo 11 landed, on the edge of Mare Tranquillitatis, the Sea of Tranquility. The seas on the Moon aren’t full of water; they’re huge basins filled with solidified lava, and NASA decided to land the first mission there. “Houston, Tranquility base here. The Eagle has landed.” If you have pair of binoculars, this would be even better. You won’t be able to see the Apollo space-flying stuff, but the view will be wonderful.
- The Draconid Meteor Shower
The October Draconid Meteor shower happens each year when the Earth runs through bits of crud leftover from the flamboyantly named comet 21P/Giacobini–Zinner, and they burn up in the Earth’s upper atmosphere. These things are about the size of grains of sand for the most part, but fire in the sky makes for quite a show. Most of the meteors appear to be coming from the constellation Draco, which is in the northern sky near the Big Dipper, but they can really come from anywhere. Once the skies are good and dark, find yourself a nice patch of northern sky, a place to sit, and wait for the fun to start. You never know how many you’ll see, but it could be amazing, especially after the Moon has set and the sky’s that much darker.
- The Big Dipper and the Horse & Rider
The Big Dipper, in the constellation Ursa Major, speak of the devil, is one of the most famous asterisms—recognizable star patterns—in the night sky. That doesn’t mean it’s not worth stopping to enjoy, though. Those seven stars are among the brightest in the northern part of the sky, and can be used to jump off to some other great things, and there are loads of deep-sky objects to see if you have a telescope. I don’t care how often I see it; just like a great pop song, I never get tired of looking at it. It’s the “Take on Me” of asterisms. There; I said it. Plus, this time of year, it sits bowl-up, like a real spoon, and looks like it takes up almost the entire northwest sky. See that second star from the end of the handle? That’s Mizar. Look a little closer (so, you’re three inches closer than many trillions of miles). It’s not just one star, but two. Can you see it? That second, fainter one is called Alcor. Mizar is actually four stars, and Alcor two, and together they’re sometimes called the horse & rider. If you can see them, congratulations, you’ve passed an ancient vision test!
Arcturus is the brightest star in the constellation Boötes, the brightest in the northern celestial sky, and fourth brightest in the entire night sky (behind Sirius, Canopus, and Alpha Centauri). It’s also one of my favorites. This time of year, it’s sort of medium-high in the western sky after sunset, and looks to be sitting alone in the deepening dusk. As you look at it, you’re seeing a red giant star, about 37 light years (LY) away. Billions of years from now, the Sun will swell up and become a red giant. To find Arcturus, all you need to do is follow the curve of the Big Dipper’s handle over to it. As the mnemonic goes, “Arc to Arcturus.”
For those of us in the northern hemisphere, there’s probably no star more famous than Polaris. It’s the north star. It’s always above the Earth’s north pole (well, 433 light years above the north pole), so you can tell what direction you’re going when you see it. If you can measure how far off the horizon it is, you know your latitude. Lots of people are surprised at how dim and unremarkable it appears in our nights; it’s only 48th brightest. Its constellation, Ursa Minor, the Little Dipper, is faint it’s hard to see for many people, which makes Polaris look like just one lone star in a mostly empty gap between the Big Dipper and Cassiopeia. To find it, use the right-hand most two stars in the Big Dipper’s bowl to lead you right to it.
- The Pleiades
Last but not least, one of the greatest things in the entire night sky is the Pleiades cluster (M45) in the constellation Taurus, the bull. It’s usually thought of as a winter sky object, but this time of year, the Seven Sisters are just starting to show their faces. To find them, look low to the east for a small, tiny, tiny dipper-shaped object. It’s not the Little Dipper (see above for Polaris), but an open cluster of hot, young stars that were formed in the same cloud of dust millions of years ago. It’s remarkable with the naked eye, but if you ever have the chance to see it through a pair of binoculars or a small telescope, it’s an astounding treat, and one that I hope I never get tired of. I can say without irony, I can’t wait for winter.
So, what about you? What do you want to see Saturday night?
Thanks, as always, for reading. I know this was a long one. I hope everyone who is in the path of Hurricane Matthew will be safe, and are as ready as they can be. That storm is incredibly dangerous, so please be safe. For everyone, as always, clear skies, and I hope to see you out there on Saturday, and have a great astronomy day whatever you do.