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When I look at the sky I easily recognize Orion, The Big Dipper, and the North Star (in relation to the Big Dipper). Besides these (and the moon^^), what easily identifiable (unaided eye) astronomical objects should I look for? (Latitude = 30 degrees North)

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The basic principle in learning the constellations is to start with the ones you know, and use those to guide you to the ones you don't know. Once you know the basic patterns of the constellations, you can then "fill in the blanks" by learning what's contained in each constellation.

For example, you recognize Orion sitting there in your southern sky. Within the constellation you've got two first magnitude stars at opposite corners: Betelgeuse above to the left, Rigel below to the right. In between are the three stars which form the Belt, and down from these hang the three stars which form the Sword. The middle star of the Sword is actually a nebula, the Orion Nebula, one of the brightest in the sky. To the naked eye, it may look a little blurry; even the smallest binoculars will show its nebulosity clearly in a dark sky.

Use Orion's belt to point you to other constellations. Follow it down to the left to Sirius, the brightest star in the sky, in the constellation Canis Major. The Milky Way runs right through this constellation then continues up to the left of Orion into Gemini, marked by two bright stars Castor and Pollux. Follow Orion's Belt up to the right, and you get to the bright red star Aldebaran, located in the middle of a large star cluster called the Hyades. A little to the right is a smaller brighter star cluster, the Pleiades. Aldebaran, the Hyades, and the Pleiades are all part of the constellation of Taurus, the Bull.

Similarly, use the Big Dipper to locate the fainter stars of the larger constellation of which it is part, Ursa Major, the Great Bear. The Big Dipper forms the body and tail of the Great Bear. In a dark sky, you can see its triangular head to the right of the "Bowl" and its long triangular feet below the Bowl. The stars of the Handle form an arc. Follow this arc away from the Bowl and it "arcs" towards "Arcturus" a bright star in the kite-shaped constellation of Bootes. The middle star of the handle, if you look closely, is actually a double star, used by the ancients as a test of good eyesight. Can you see that the brighter star, Mizar the Horse, has a tiny rider named Alcor?

That's the sort of stuff I talk about when I give sky tours. The key to it all is that all the stars maintain the same positions to each other all the time. The sky rotates, but Orion's belt always points to Sirius and Aldebaran, and the handle of the Dipper always arcs to Arcturus. Once you learn these basic geometric arrangements, they will never let you down.

Once you've learned the basic patterns of the constellations, look for the interlopers, the bright planets, usually brighter than any of the stars beyond them. Just after sunset, Jupiter and Venus are shining brightly in the west, but moving apart quite rapidly. Mars is rising in the east, close to Regulus in Leo, followed a few hours later by Saturn, close to Spica in Virgo.

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If you can see Orion, you should have no trouble finding the Pleiades, and they can't really be mistaken for anything else in the sky.

If the sky is not too dark, or your eyes poorly dark-adapted, they may initially appear as just a dim blur, covering an area roughly comparable to the Moon's disk, but even on a moderately dark night they'll easily resolve to a cluster of individual stars, the brightest of them looking a bit like a miniature Big Dipper:

PICTURE

With even modest binoculars, a lot more detail will become apparent. Also, while looking with binoculars in that general direction, go take a look at Orion's sword, whose middle "star" is actually the Orion nebula; while you need a telescope to really observe the nebula in detail, distinguishing it from a star is just possible even with the naked eye, and easy with binoculars.

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In the summer, at your latitude, you should be able to easily recognize Scorpius as a, well, scorpion-shaped constellation and, right behind it, look for the "teapot" of Sagittarius.

In the fall, you should be able to see the big cross of Cygnus flying south for the winter.

Opposite from the Big Dipper is Cassiopeia, which may look like an "M" or a "W" depending on time.

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Let's take a look tonight around 10 p.m. Daylight Time. Look straight overhead and you will see the three bright stars which form the Summer Triangle. Vega is the brightest in the small constellation Lyra, looking like a small parallelogram. Deneb marks the head of the Northern Cross, or the tail of the Swan, Cygnus. Finally Altair marks the eye of Aquila, the Eagle. South of Aquila is the constellation Sagittarius, which looks more like an old-fashioned teapot.

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You will be able to see a good portion of the ecliptic and therefore the other planets will make an appearance throughout the year.

Unaided you should be able to see Jupiter, Saturn, Mars, Venus, Mercury (close to the sun) with ease when you know where to look.

Have you tried a program like Carte du Ciel? (freeware) which maps the night sky for you.

Also there is M31 the Andromeda galaxy to see if you can get somewhere dark and the band of the milky way is pretty prominent even in suburbs.

Have fun!

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Cepheus is easy to find. It's a square next to Cassiopeia (which is also pretty easy), and it contains the interesting Delta Cephei.

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