Weekend Sky Report

This weekend, if we're lucky to get clear enough skies, check out one of the best moon phases

for lunar observation.

Right in the center of Taurus the Bull is the bright orange giant Aldebaran. Aldebaran is close… just over 60 light years away. And because of that, it’s easy to miss what’s behind it… about 90 light years behind it, to be exact. But even then, at over 150 light years away, the Hyades is one of the closest open star clusters. Compare that to the Pleiades at well over 400 light years away.

In Greek mythology, the Hyades are daughters of Atlas. As are the Pleiades… and following the death of their brother Hyas, their grief transformed them into stars. And their weeping for the loss of their brother… makes the rain.

When it’s not raining, you can see the Hyades by finding their sisters, the Pleiades in the eastern sky this evening. When you find the Pleiades, which is a cluster of bright blue stars you can easily see with the naked eye, look beneath it to find the bright, orange Aldebaran. Then grab your binoculars or any telescope and look straight at it… you’ll notice several bright white and yellowish stars just below and to the right of Aldebaran...and there you have it. The Hyades. Now, along with Aldebaran, the four brightest stars of the Hyades make up the head of Taurus the Bull. And since the Hyades is one of the closest and most studied open star clusters in the sky, we’ve known for a while why those four stars are so much brighter than the rest of the cluster. They’ve exhausted their core hydrogen and are evolving into giants. One of the final stages before their demise… in a few million years.

Observations of the bright, open cluster known as The Pleiades have been recorded since the 17th century BC, and likely even before that. It was scientifically and spiritually significant to many ancient cultures across the globe, and continues to educate and inspire observers today.

The Pleiades is a collection of B-type stars, which are bright, hot, and blue in color. And the stars of the Pleiades are close too—around 450 light years away, which contributes to its brightness. And while you don’t need a telescope or even binoculars to appreciate the Pleiades, it certainly helps.

The Pleiades is also known as the Seven Sisters, after the seven daughters of Atlas and Pleione in Greek Mythology. Observers with good eyesight under dark skies will count seven stars in the cluster. It wasn’t until Galileo looked at the Pleiades through his telescope that dozens of other stars were discovered. Since then, further scientific observations and subsequent calculations have estimated over a thousand stars in the cluster.

To see the Pleiades for yourself, look to the eastern sky in the evening—the later it is, the higher it will be. To the naked eye under suburban skies, it could be confused as a small cloud. Under darker skies, it’ll look more like a star cluster. Once you find it, grab your binoculars or a telescope. Once you look at the Pleiades with a little help, you’ll quickly realize why this star cluster has captured the human imagination for thousands of years.

Saturday night is the spookiest night of the year. Not just because it’s Halloween… but also because it’s a Halloween with a full moon. This sort of thing happens about once every 18 or 19 years. Less rare, but still pretty rare is the fact that it’s also a Blue moon, meaning it’s the second full moon in the calendar month. We get a blue moon about every 2.5 years. The last one we saw was March of 2018.

But because Halloween is the last day in a 31-day month, and the lunar cycle is 29-and-a-half days, every Halloween full moon is a blue moon.

And even though the full moon officially happens one night out of the month, it’ll appear full all weekend. On Friday night, it’ll rise just before 7pm. Saturday night, trick-or-treaters will be able to see it just above the horizon around 7:15. On Sunday night, it gets confusing because it’ll rise again before 7pm--yet another trick... the end of Daylight Saving Time.

Of course, the full moon through binoculars or a telescope can be fun, but if you’re looking for more treats, there are plenty of other bright targets to appreciate this weekend as well. In the evenings, bright orange Mars will be high to the southeast, while Jupiter and Saturn will be setting toward the southwest. Grab a telescope--any telescope--even good binoculars, and you’re likely to see Jupiter’s four largest moons, and the rings around Saturn.

So, if we’re lucky enough to have clear skies on Halloween, you’ll have plenty to scream about.

We all know about… the dippers. Ursa Major and Ursa Minor—the big and little dippers. We know about them because they’re out every night. But there’s another bright northern-hemisphere constellation you should know about… Swirling around the northern sky year-round are the five bright stars that make up… Cassiopeia.

Cassiopeia is popular with amateur astronomers because it’s large, bright, and the main reference point for several deep-sky objects. Things like Double Cluster, the Andromeda Galaxy, Messiers 52 and 103, both open star clusters, and the Owl Cluster, also known as the E.T. Cluster. Yes, THAT E.T. It’s called that because apparently it looks like the movie character. I don’t really see it, but I do enjoy finding it when I can.

Anyway, this weekend, you can find Cassiopeia high to the northeast after sundown. If you were to draw lines between its five bright stars, it would look kind of like a wonky lowercase “W” on its side.

Interestingly enough, if we were to take a quick trip to nearby star system Alpha Centauri, our own sun would appear in Cassiopeia. It would turn the “W” into a bit of a squiggle, and would be appear to be by far the brightest star in the constellation.

Cassiopeia has inspired novels, movies, TV shows, even songs. If we get a clear night this weekend, maybe look up for a little inspiration of your own.

While the moon is pretty to look at and easy to find, its light outshines a lot of deep sky objects. Galaxies, star clusters, nebulae… So moonless nights are what amateur astronomers live for.

One of the brightest deep sky objects, and therefore a good one to start with, is Messier 22--a globular cluster in the constellation Sagittarius.

M22 was one of the first globular clusters ever discovered. It was found by German astronomer Abraham Ihle (EEL-uh) in 1665, and later added to Charles Messier’s famous list of comet-like objects that we now know are immense, but distant and dim celestial objects. Not so dim though that today’s amateur telescopes can’t find them--especially M22. It’s one of the brightest of all globular clusters. Just about any telescope should reveal it, but you may have to look for a while before you find it. To do so, find Saturn and Jupiter--two bright points of light in the southern sky with Saturn on the left, and bright Jupiter on the right. Trace an imaginary line from Saturn to Jupiter, and continue that straight line about that same distance past Jupiter. Then with a telescope, any telescope, scan just a little further to the right and ever-so-slightly downward. When you see what looks like a fuzzy star, stop. You’ve found it.

Globular clusters are some of the best deep sky objects to start with because they’re easier to spot than galaxies and dimmer open clusters.

If you have any trouble finding Messier 22, find me on Twitter @MattPelsor for a visual guide.

Mars, Jupiter, Saturn, Uranus, AND Neptune will all be in the evening sky this weekend. And so will Pluto, if you still consider it to be a planet, but most amateur telescopes won’t have a chance of spotting it.

To see them all, you’ll need a decent telescope. To see the three brightest ones, you just need your eyes. Let’s go from East to West.

At around 10pm, you’ll notice a bright orange point of light in the night sky that doesn’t twinkle. That’s Mars, but further East, or to the left, is Uranus. In fact, it’ll be almost due east at ten o’clock, and slightly lower in the sky than bright Mars. Now, you can’t see Uranus with the naked eye unless conditions are perfect--dark skies and no atmospheric interference. And even then, it’s tough to spot. But with most telescopes you should be able to see something. If you spot a pale blue-green disc, you’ve found it.

Again, you can’t miss Mars… it’s bright, and has that distinct red-orange hue.

Now for the hardest one to spot… at 10pm, Neptune will be high to the south/southeast. You’ll need a large telescope to find it. Neptune wasn’t even discovered visually--it was discovered mathematically in the mid 19th century by studying the orbit of Uranus. Again, if you have a particularly good telescope, look for a dim, deep blue disc.

And to the southwest, you’ll see two brighter points of light that don’t twinkle. The dimmer yellow one is Saturn. Any telescope will reveal its rings. An amazing sight from your backyard. The brightest point of light to the west or right of Saturn is Jupiter. Binoculars should be enough to see its four Galilean Moons.

Oh, and Pluto? It’s right between Jupiter and Saturn… but you won’t be able to spot it unless you have an enormous telescope and know exactly what you’re looking for.

The moon will rise just after 8pm Eastern Time on Friday night. Just to the left of it will be a bright orange dot. The planet Mars. The two objects will be close enough that you should be able to see both in the same field of view through a modest pair of binoculars, depending on the magnification. Most telescopes get too close to see both in the eyepiece, but if you have a telescope--even a small toy telescope, you know just how striking the moon can be. If you haven’t gotten yours out in a while, get it out this weekend. Not only do you have the moon and Mars, but also Jupiter and Saturn. Jupiter is the brightest object behind the moon, but Mars isn’t far behind in brightness. Thankfully, Mars is on the other end of the southern sky, and has a distinctively orange hue. And of course it’ll be right next to the moon on Friday night, so there’s no confusing which one’s which. However, if you observe on Saturday or Sunday, look for Jupiter and Saturn due south around 8:30, and west of that if you go out later with Jupiter on the right and dimmer, yellowish Saturn on the left.

If you have a larger telescope, and you plan on being up late on Saturday night, scan just above and to the left of the moon with the scope and look for a light blue disc. That’s Uranus. And if you have a really big telescope, you probably already know that Neptune is also out and will be due south just after midnight.

So, with the right equipment, you can see all of the outer planets this weekend. But you’ll see half of them, plus Mars… with just your own two eyes.

On Friday night, the moon rises just before 5pm, so by dark it will be high to the south/southeast. If you look at the moon on Friday night with a telescope or binoculars, look toward the shadow--what’s called the terminator, for details on craters and mountains--especially one of its more famous craters, the Tycho crater. One of the only craters you can really make out with the naked eye during a full moon--it’s the one with the spikes of impact ejecta coming off of it. On Friday night, that crater will fall right along the lunar terminator, so you’ll see a lot of good definition, including the central mountain peaks from the impact. Once you’re done looking at the moon on Friday night, you may notice a pale yellow point of light right above it. That’s Saturn. Just about any telescope, and even some binoculars will reveal Saturn’s rings and some of its moons. Larger telescopes will even show the Cassini Division--the dark gap between the two most visible rings. Once you’re done with Saturn, look just to the right, or further south for the second brightest object in the sky behind the moon. That’s Jupiter. A pair of modest binoculars will reveal its four largest moons--the ones Galileo discovered when he first looked at Jupiter through one of the earliest telescopes. If you have a larger telescope, you may want to observe Jupiter on Sunday night around 8pm when the Great Red Spot will be in view. Now these days, the Great Red Spot is more of a pale orange, but you can still make it out through decent telescopes with good magnification.

Oh, and Fall is a great time to watch the full moon rise. Look due East this coming Thursday October 1st just before 8pm for a dazzling show.

Tonight’s target has been known since LONG before the telescope was invented. This of course means it can be seen WITHOUT a telescope, but ONLY under very dark skies. And it wasn’t until the early 1800s that, THANKS to the telescope, it was identified as two separate clusters instead of one.

The aptly named Double Cluster is a favorite among budding amateur astronomers. Not only because its brightness makes it easy to find, but also because its beauty keeps observers coming back.

And here in the Northern Hemisphere, Double Cluster never dips below the horizon… so depending on your view, it’s out all night!

To find Double Cluster, look for Cassiopeia. You’ll find it in the northeastern sky in the evening. The later you’re out, the higher it will be... Cassiopeia looks like an elongated, oddly-proportioned “W.” Once you find it, look for the two stars closest together in the constellation. If the “W” were on its side, as it will be tonight, it’s the second and third stars from the bottom. Trace a line between those two stars, then scan down with binoculars or a telescope… following that same line. When you see a double cluster of stars, guess what… you’ve found it. Two brilliant clusters of mostly bluish white stars—but there are a few bright yellow and orange stars for variety.

When you find it, you’ll be looking at one of the younger star clusters you can easily find in the night sky… at only about 13 million years old. To give you an idea, Kangaroos evolved on Earth about two million years BEFORE these stars formed.