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Tonight’s Sky – Feb/Mar P a g e | 1

Materials for Show: Clear weather Dimly Lit, Open area Binocular Print outs of Messier Objects or have them loaded on a tablet M82 Cigar : https://astropix.ipac.caltech.edu/image/esahubble/potw1201a M101 Spiral Galaxy: https://astropix.ipac.caltech.edu/image/esahubble/opo0907h M42 Orion : https://astropix.ipac.caltech.edu/image/stsci/STScI-PRC-1995-45-a M1 Crab Nebula: https://astropix.ipac.caltech.edu/image/esahubble/heic1614a M51 Whirlpool Galaxy: https://astropix.ipac.caltech.edu/image/esahubble/opo1103c Optional: Telescope, Green Laser pointer

Welcome to ______. The beauty of our night sky is best experienced in total darkness, so I’m going to ask you to silence all digital devices.

Since I was a kid, I’ve always wanted to learn how to find , and in the night sky. What do you see? There are a few here and there, but it seems kind of dull. Any guesses as to why that is? This is due to light pollution which hinders our ability to see the stars as we used to before the abundance of city lights. A Dark Sky location is defined as anywhere you can see the Milky Way with the naked eye. I’d like you to think about what it was like through most of human history: before cell phones, the internet, television, even before radio. We humans have looked to the sky and used the stars, not only to tell stories, but also to find our way around. Though we no longer use them for navigation, stars and constellations continue to influence our culture today.

The easiest constellations to locate, especially this time of , are Orion and the . Take a moment and see if you can find them without my help. (Wait) Did you find it?

Point out Ursa Major.

There it is, Ursa Major (or the Great Bear) AKA the Big Dipper, with the possible exception of Orion, no other is as well-known or has more stories about it. The Big Dipper is the third largest constellation and is known for the seven bright stars that form the . Ooooooo there is a big word. A constellation’s asterism is a distinct, easily recognizable group of stars. The Big Dipper is so recognizable it has many names including Ursa Major, the Plough, the Wain, or the Wagon. In the Big Dipper, some of the main stars are Mizar, Dubhe (Pronounced “Dub”) and Merak. Tonight’s Sky – Feb/Mar P a g e | 2

Point out Mizar, circle Dubhe and circle Merak.

Interestingly, Mizar was used by both Native Americans and as a test of eyesight. Regardless, The Big Dipper is always connected with the Little Dipper.

Point out Ursa Minor.

Ursa Minor (or the Little Bear) is more commonly known as the Little Dipper and it is quite important mainly because of one , Polaris.

Point out Polaris

Have you ever heard of the North Star? The North Star marks the celestial north pole. While not the brightest star in the sky (actually it is the 49th brightest), The North Star never sets and will reliably mark North for the next few thousand . An easy way to find the North Star, because the Little Dipper is sometime drowned out by light pollution, is to use some of the stars in the Big Dipper, namely, Dubhe and Merak. If you were to draw a line from these two, five times the distance between them, they will point to Polaris.

Next, let’s focus our attention on the other easily found constellation, Orion.

Point out “Orion”

No other group of stars looks so like its name (The Hunter) or contains so many bright stars. Orion’s alpha star, marks Orion’s eastern shoulder and is a noticeably red star.

Point out Betel/Rigel

The beta star, Rigel, is among the top 6 brightest stars. Orion also contains Bellatrix (Point out Bellatrix) at his western shoulder. Now where have I heard that name before…?

We need one more constellation and we’ll have all the tools we need now to form a celestial clock. This constellation is called Cassiopeia (Point out Cassiopeia) and she looks like a big W in the sky. Picture Polaris as the center of a clock. See how Cassiopeia and Orion are opposite of each other? The sky over time seems to rotate around Polaris, remember the Tonight’s Sky – Feb/Mar P a g e | 3

North Star doesn’t move. So in 12 hours, Cassiopeia and Orion will switch places. If you find these constellations at dusk and correlate them with a stationary landmark…like a tree…then you can infer dawn as they trade positions.

A line drawn to the northwest from Orion’s belt points to Aldebaran (hit “Line to Aldebaran”) a bright orange-red star (Point out Aldebaran) that is the eye of the bull, Taurus.

Point out on Taurus

Taurus is amongst the oldest constellations of the Zodiac. See different cultures had different constellations and different names for those constellations. On the bull’s shoulder do you see that cluster of stars that looks like another dipper? That is the Seven Sisters, also known as the Pleiades.

Orion, Aldebaran and the Seven Sisters show up in fantasy novels and shows all the time. I mean we’ve already referenced how Bellatrix, Sirius, Nyphadora, and Andromeda influenced names in Harry Potter. Has anyone in here read The Lord of The Rings by JRR Tolkien? In the first installment, The Fellowship of the Ring, Frodo, Sam, and Pippin are beginning their great journey, still in the Shire and already shadowed by Black Riders, when they take refuge for a night with the Elf Gildor and his companions. “On that night, ... high in the East swung Remmirath, the Netted Stars, and slowly above the mists red Borgil rose, glowing like a jewel of fire. Then by some shift of airs, all the mist was drawn away like a veil, and there leaned up, as he climbed over the rim of the world, the Swordsman of the Sky, Menelvagor with his shining belt.” Remirrath (the Seven Sisters) precedes Menelvagor (Orion) and Borgil has been convincingly identified as Aldebaran. Who says making stories about the stars is an old human habit…? Seems to me like it still happens.

And since Taurus is a part of the zodiac, let’s talk about another one, Leo

Point out Leo

Leo, like Orion, is one of the few constellations that look like the characters for which they are named. Denebola (Point out Denebola”), the beta star of this constellation, is also one of Tonight’s Sky – Feb/Mar P a g e | 4 the four stars that form the Spring Diamond. You’ll have to come back in a few months to see that formation.

Another one of the zodiac that has some pretty interesting objects is Cancer (Point out Cancer) along with (Point out Hydra). Hydra is the largest and longest constellation in the sky. It takes more than 6 hours for this whole constellation to rise in the northern hemisphere. The alpha star, Alphard (Point out Alphard), was the only named star in the constellation and by far the brightest. Recently in 2016, Sigma Hydra (Point Sigma Hydra), or Minchir, became the second named star in hydra.

Now here is a simple and funny constellation called Canis Venatici. (Point out Canis Venatici) It’s really just two stars, but a trick I use for finding it is by finding the Great Bear and...yeah…you get the idea.

While looking at the constellations is great, sometimes what looks like a star to the naked eye is something much more. There are also galaxies, nebulas and star clusters that are quite interesting; some can even be seen with nothing more than a binocular or a small telescope.

While the Little Dipper does not contain any such objects, The Big Dipper more than makes up for that. M81, also known as Bode's galaxy, (Point out M81) is a large bright spiral galaxy located 11.8 million light-years away. It's easily visible with binoculars and is a superb target for all sizes of telescopes. In the same area as Bode’s Galaxy is another prominent galaxy, M82 (Point out M82). M82 is fainter than M81 and a very different type of galaxy. It's a starburst galaxy, meaning stars are being formed at exceptionally high rates. M82 is also known as the Cigar galaxy. Here are some images the Hubble Telescope was able to capture of the Cigar Galaxy. (Show M82 Cigar Galaxy”)

M101 (Point out M101) is a large face-on spiral galaxy located 22 million light-years away also located in the big dipper. While it can be glimpsed with binoculars or small telescopes, this galaxy suffers from low surface brightness and in bad seeing conditions or light polluted areas is sometimes difficult to spot. It is best viewed from dark sky sites on the Northern Hemisphere during the months of March, April and May. Locating the part of sky where M101 is positioned is easy, since it's close to the handle of the bowl that forms the spoon of the Dipper asterism. Let’s take a closer look (Show M101 Spiral Galaxy) Tonight’s Sky – Feb/Mar P a g e | 5

Now let’s check out something cool in Orion. Of the many star clusters and nebulae that are within Orion, only M42 is visible with binoculars or telescopes, but you don’t need them. M42 (Point out M42), also known as the Orion Nebula, is easily visible to the naked eye but when you can use a telescope, you are in for a real treat (Show M42 Orion Nebula).

We’ve already talked about the Seven Sisters, a (Point out M45) in the constellation Taurus, however, Taurus also contains the famous Crab Nebula, M1 (Point out M1). These cloudlike remnants of a supernova explosion of a massive star and can be seen in a small telescope although a large telescope is needed to see the central star. (Show M1 Crab Nebula)

Located within Leo are four spiral galaxies M65, M66, M95 and M96 (Point out M65, M66, M95 and M96”) All are visible with binocular on a clear night.

Even though Cancer is the least visible constellation in the zodiac, just a little bit above the fork in the stars is M44 (Point out M44), an open star cluster known as the Beehive. A fine sight with binoculars or a small telescope, it contains about 75 visible stars.

And while it’s a small constellation, Canis Venatici contains a wealth of deep sky objects including M3 (Point out M3), an easily seen star cluster, M51 (Point out M51), the well- known Whirlpool Galaxy, M63 and M106 (Point out M63 and M106), both spiral galaxies. One of the best images taken of the M51 Whirlpool Galaxy was taken by the Hubble telescope. (Show M51 Whirlpool Galaxy)

Our night sky has many, many wonderful sights to share. I am reminded of the words of the late Carl Sagan, “Before we invented civilization our ancestors lived mainly in the open out under the sky. Before we devised artificial lights and atmospheric pollution and modern forms of nocturnal entertainment, we watched the stars. There were practical calendar reasons of course but there was more to it than that. Even today the most jaded city dweller can be unexpectedly moved upon encountering a clear night sky studded with thousands of twinkling stars. When it happens to me after all these years it still takes my breath away.” We just have to remember to look up.

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