Star Parties 101
We Live in a pinwheel of stars
A few things I have learned about BLACK HOLES
A Beginner’s Scope
Looking East in December
Understanding the Phases of the Moon
Star Hopping in Scorpius
Star Hopping in Sagittarius
Nebulae

Web sites for beginners
Books and Magazines
Local Astronomy Related Stores & Outlets
Observing Essentials
Observing Upgrades

Was it or wasn’t it? I had been working on the problem for an hour now, and I was starting to get frustrated. I was looking into the status of Polaris; I knew it was a double star but was it an optical double or a true binary system where the stars were gravitationally bound? And why did I care so much? I was including Polaris in my repertoire for that evening’s star party and, true to my nature, I was adamant about giving people the right information. Skymaps.com listed the companion as “an unrelated magnitude 8 star”, Burnham’s made it sound like a binary star, and Double Stars for mall Telescopes by Sissy Haas claimed its status was “unknown”. In desperation, I finally turned to the one source I dreaded as a graduate student: professional journal articles. These days, however, I actually love journal articles since they were a welcome distraction from the world of Play-Doh, Barbie and SpongeBob.

But I really needed to take a deep breath and focus! In a few hours I would need to pack up the car for the star party. It’s so strange to think that not so long ago I did these star parties all the time. Before my husband Jeff and I had kids, we would take the scope out with friends and invite my astronomy-lab students out for extra credit. Or I would take my students out during class time so that they could observe deep sky objects instead of just watching a slide show. Schools and organizations were always calling UNLV asking for our help. And I would be only too willing to do my part. How did I prepare for a star party back then? Well, back then I didn’t have two very stubborn kids vying for my attention and trying to kill each other every chance they got. Over time, a standard set of procedures evolved. First, I’d think about the environment where we would be viewing so I would know the types of objects that could be seen. Then I’d consider my audience, lick out a list of objects to view, and jot down some interesting facts to wow the folks.

Know Your Environment - A lot of things fall into this category. First and foremost, what is the observing site like? What will be blocking your horizons? How bad is the light pollution? These factors will definitely drive your observing selections. I always make a point of visiting a site at least once before the viewing session so there will be no surprises.

What will the viewing conditions be like during the star party? Keep an eye on the weather forecasts, but remember a forecast of “clear skies” on The Weather Channel doesn’t tell the whole story. I use the Las Vegas Clear Sky Clock (http://cleardarksky.com/c/VegaNVkey.html ) to determine how winds, clouds, transparency, and seeing will limit my observing choices for the night.

If you are addressing a specific group, always have a backup plan in case telescope viewing is out of the question. Have one or two slide shows prepared ahead of time so you always have them ready. Even if you have seen them a million times before, chances are many in the audience are viewing the images for the first time. For school children, you can also plan an activity. I like having the kids act out the Sun, Earth, and zodiac constellations so that they understand why we see different stars at different times of the year and how the Sun “appears” to be in a constellation. When I tell them they catch on faster than my college students, they are quite proud of themselves!

Pick Your Targets - Who is your audience? Are they mostly older adults, school kids, or a mixture of both? If you’re doing a star party for younger children, they may not be as excited with the “dim fuzzies” as an older crowd would. In this situation, you may want to stick to the planets, the moon, and brighter star clusters. Case in point: my college students were “underimpressed” with the Crab Nebula from Sandstone Quarry, but I made them observe it anyway because they needed to get a broad sample of deep sky objects. However, when I showed the Crab Nebula to a more a mature couple at a Red Rock star party – even under less than optimum viewing conditions – they were fascinated when I explained to them what they were seeing.

So now you know what parts of the sky you have to work with, your audience, and the conditions you will be facing. At this point I like to inspect Skymaps.com to get an idea of what types of objects will be up. This website is great because not only does it give you a sky map and lists of naked eye, binocular and telescopic objects to shoot for, but it also gives you basic information about the objects. I print out a couple copies to take with me. I don’t really use the sky maps; I usually end up giving them away to some very inquisitive visitors during the night.

Next, I check for planets. If Jupiter or Saturn is up, I then look at a simulation on Sky & Telescope’s website to determine where their satellites will be during the star party (http://skytonight.com/observing/objects/javascript/jupiter and http://skytonight.com/observing/objects/javascript/saturn_moons). I’ve made a habit of checking the positions of all the planets, even the ones that aren’t visible, just in case someone asks

Questions, anyone? - To me, preparations are not complete until I’ve done a bit of research. People are always asking: What is it?, How big is it?, How far is it? and Where is it? I do my best to have the answers ready. It’s okay if you don’t know or take an educated guess, as long as you’re honest about it. But you can really blow them away if you just snap off the right answers.

One of the best purchases I ever made was the two-volume Finder Charts of the Messier Objects published by Sky Spot (http://www.sky-spot.com). If you have a telrad on your scope, then you need these books. It has finder charts for all 110 (ok, really 109) Messier objects, showing you where to point the telrad reticule. Additionally, it tells you what type of deep sky object it is, its size and distance – all common questions. I found that some of the information is outdated due to recent HST observations, but it is definitely in the ballpark.

I’ve also started carrying a small notebook with me to star parties. In it I jot down some numbers, diagrams, and interesting tidbits regarding the objects I plan to observe that night. I’m pretty good at remembering facts and figures, but this way I can relax knowing that I have the information close at hand.

Keep an eye out for current astronomical events (http://science.nasa.gov/headlines, http://skytonight.com/news/wires). Last August there was an email hoax making the rounds claiming Mars was very close to Earth and that the planet appeared as large as the full moon. Since this made headlines in two newsletters I receive, I was prepared at that month’s Red Rock Star Party. When a guy came up and asked if I had seen Mars lately, I replied excitedly, “Yeah……oh man, it’s as big as the full moon!” He answered breathlessly, “Really??!!!” to which I stated, “No, not really. It’s just a hoax.” Luckily, he had a pretty good sense of humor!

The Big Show - So you’re at the scope, and the crowds are about to materialize. What do you look at first? I have always viewed star parties (and teaching, for that matter) as sort of being “on stage”. I like to entertain the masses. That way, people are having too much fun to realize they are actually learning. So I build up to a grand finale. First, maybe a double star or an open star cluster to whet the appetite. Next, perhaps a nice planetary nebula followed by a globular star cluster to get the crowd going. I’d definitely leave crowd pleasers like the Orion Nebula or the Lagoon Nebula for the end, followed only by Saturn or Jupiter. I usually don’t like to observe when the moon is out – a throwback to my professional days I suppose – but if it is up, I’ll save the moon for the very end. Try close-up views of the terminator as it crosses mountain peaks.

I’ll be the first to admit that public star parties can sometimes get old. That’s why I work so hard at preparing for one. I like to learn new things about celestial objects, or find an interesting factoid to throw out that puts things in perspective. Each time I take out the telescope I try to find an object I’ve never located before. These things keep it exciting for me, even when it’s the thousandth time I’ve looked at the Andromeda Galaxy. And if you’re excited, it shows. Even in the dark.

We Live in a pinwheel of stars
By Bob Sherman

On dark, clear, moonless nights, far from city lights, you can see a hazy band of light stretching across the sky. If you look at this glow with binoculars, you will see that it is light from millions of stars. These stars, and all the stars you see in the night sky, are part of a huge system of stars called the Milky Way galaxy.

Our sun is a star in the Milky Way, too. So, when you look at the sky from Earth, you are looking at the Milky Way from the inside. If you could view our galaxy from far away, it would look very different.

Imagine that you are a space traveler in a rocket ship far from our galaxy. From your spaceship window, the Milky Way looks like a glowing pinwheel. In the center of the pinwheel, you see a bright yellow bulge. Spiraling out from the center, the arms of the pinwheel look light blue against the darkness of space.

Old Stars, New Stars

As you rocket closer, you see the Milky Way is made up of stars and clouds of glowing gas. The center of the galaxy is a mass of old yellow, orange, and red stars, formed when our galaxy was young. They have been burning for a long time. In the outer spiral arms of the galaxy, new stars are being formed. The brightest of these young stars are very hot and, like a really hot flame, they give off a blue light.

Our sun is a yellow, middle-aged star about halfway out from the galactic center in one of these brilliant spiral arms. But you probably wouldn’t even be able to pick out our sun in the blaze of starlight coming from the galaxy. That dazzling light comes from more than 200 billion stars!

As your spaceship finally reaches the outer edges of the galaxy, you may worry that you will crash into some of those stars. But the stars are spread across a lot of space. The Milky Way is so big that it takes light more than 100,000 years to travel from one side of the Milky Way pinwheel to the other. If you built a scale model of the Milky Way with each star the size of a grain of salt, your model would have to be twenty-five times wider than the Earth. In this model, the grains of salt in the spiral arms would be seven miles apart. So even though our galaxy is enormous, it is mostly empty space.

Speeding Stars

The Milky Way not only looks like a pinwheel, it spins like one, too. All the stars are speeding around the galactic center. Our Sun is traveling at 140 miles per second. That’s three hundred times faster than a speeding bullet. The Earth moves with the Sun in its rapid journey around the galaxy. We don’t feel as if we are moving for the same reason airline passengers feel no motion when their plane is cruising at a steady speed.

The Milky Way is one of 100 billion galaxies in the universe. Most of these galaxies are too far away for us to see without a telescope. The Andromeda galaxy, one of the Milky Way’s closet neighbors, is more than 10 billion, billion miles away. When seen through a powerful telescope the Andromeda galaxy is a beautiful swirl of flowing gas and billions of stars. No one has ever seen the whole Milky Way through a telescope. It’s not possible to take a rocket ship to Andromeda to look back at the Milky Way. So how do we know what our galaxy looks like?

“Seeing” the Milky Way

Even without a telescope we can see that the stars have different colors: light blue, white, yellow, and orange. We can easily see that some stars are brighter than others. But to understand what our galaxy looks like, we have to know the distance from Earth to each star. That is the hard part. To determine distance for each star, astronomers compare the positions against the back drop of distant stars and galaxies. As the Earth moves around the Sun, the stars appear to move, much as trees appear to whiz past your car window as you drive by. The closer the tree, the faster it appears to move. Using this idea, astronomers have been able to determine the distance of stars from Earth.

By carefully plotting the positions, color, and brightness of each star, astronomers discovered that a large number of yellow stars were clustered in one place, surrounded by bands where younger blue stars are being formed. That is exactly what they saw in their telescopes when they looked at distant spiral galaxies such as Andromeda and M100. Seen from far away, the Milky Way would look similar to these galaxies. You may not be able to take a rocket ride into deep space, but you can see the Milky Way galaxy. All you need to do is look up at the night sky.

How the Milky Way Got Its Name

Thousands of years ago the Greeks saw a faint band of light in the night sky and thought it looked like spilled milk. So they named it the Milky Way! In fact, our modern word for a large collection of stars, galaxy, comes from gala, the Greek word for milk. We now know that this band of light is one of the spiral arms of the Milky Way, our home galaxy.

A few things I have learned about BLACK HOLES
By Bob Sherman

No known force can destroy it. Over time, it only grows larger as it swallows everything that comes close. Eating away at the known universe, it consumes mass, heat, light, structure, and even information - it is a one-way exit door out of our universe.

Presently, research is still being done to uncover the exact features and characteristics of black holes. Since no electromagnetic radiation comes from a black hole, observers on Earth cannot see them. The only way astronomers have been able to determine the structure of a black hole is through the use of equations of general relativity.

There are a few things that astronomers have surmised. One is an area called the event horizon, which is the boundary between the endless darkness of a black hole and the rest of the universe. Second, we can detect black holes by observing gravitational waves, which are caused by massive stellar bodies losing their magnetic fields when collapsing into a black hole. Third, astronomers have been able to assign classifications to black holes.

One type of black hole, called a Schwarzschild black hole does not rotate. The second type of black hole, which does rotate, is called a Kerr black hole. The Kerr black hole is not so much spherical as the Schwarzschild black hole as it is more doughnut shaped, with the ergoregion surrounding the event horizon.

In the past decade, a few things have occurred that have helped further research in this area of black holes. A positive byproduct of new technology came in the form of new ways of measuring black holes. The traditional method of measuring black holes was to observe the effect of gravitation by the black holes on nearby stars. The problem with this was that uncertainty arose when dealing with distant stars. The new method deals with the observation of the amount of gas entering a black hole. By measuring the mass that enters a black hole, the mass that the black hole contains can be determined.

The black hole is an area of physics and astronomy that is still controversial, but has been cleared some by new research and constant debating. These enigmatic stellar objects may never be fully understood, because they are only truly explained by theories and mathematical equations. Since the average person on Earth cannot observe black holes, they may not care to understand more about them. But through understanding more about the black hole and the science that explains it, we understand more about the history of our universe, as well as the fate of most stars. Black holes may never directly affect us, but they represent the embodiment of what astronomy is all about:

A Beginner’s Scope
By Rob Lambert

What telescope should I buy? The first question often asked when the public visits one of our LVAS star parties is not easily answered. If you were to ask 10 people what should a beginning astronomer consider as their first telescope, you would most likely get 10 different opinions. The number of opinions would probably decrease if you were to only ask members of the LVAS, since we seem to be inclined toward similar opinions. Well, I’m going to attempt to give you the opinion of a relatively new amateur astronomer, since I’ve only been enjoying this fascinating new hobby for less that a year and a half. Hopefully, you’ll find some helpful guidance in what follows.

To begin with, I must agree with our President, Geary Keilman and many other LVAS members. Stay away from the department store offerings that tout 500x or greater magnifying power for less than $200. Buying one of these cheap, and I mean cheap department store scopes will quickly place you on the road to frustration and disappointment. These scopes use inexpensive components and have very flimsy mounts. Fortunately, this was the first piece of sage advice I received from LVAS members when I first began considering what scope to buy. Unfortunately, some of my friends didn’t listen to this advice and they have been sorely disappointed in what they got or better yet, didn’t get for their money.

When considering what scope you should buy, you have to first decide how much you are willing to spend. Most new amateur astronomers don’t have an unlimited budget and must set a limit on what they can spend on a hobby. Deciding how much you can spend will determine which route you can take. I’ll base my recommendations on this premise.

If you want to get started in amateur astronomy and have only around $100, don’t fret; there’s even a path for you that will benefit you in the long run. For your $100 you should start with a set of binoculars. Some decent binoculars can even be purchased from WalMart, but I would recommend you buy your binoculars from Orion Telescopes and Binoculars. Your binos should be 7 x 50 or 10 x 50, where the first number is the magnification and the second number is the size of the objective lens. I have a set of 15 x 50 binos, but any binos over 10x are difficult to hold still enough for stable viewing. Orion has several binos for $100 or less. For $99.95 there are two choices of Orion Scenix binos, either 7 x 50 or 10 x 50.

If you feel you must have a telescope right way, most LVAS members would suggest that a Newtonian reflector on a Dobsonian mount provides the best value for the beginning astronomer. Some tripod mounted scopes are difficult to set up and align and are too complex for youngsters to operate. A Dobsonian reflector may not look like the beginner’s idea of a telescope, but they offer more viewing capability and ease of use per dollar spent. Following are some suggested telescopes you might consider, depending on your budget. These are only suggestions from one relatively new amateur astronomer and before running out to buy a scope, spend some time at LVAS star parties and check out our scopes.

Under $200 - The Orion StarBlast Astro Telescope. This is a basic Newtonian reflector on a modified Dobsonian mount - a simple point and view tabletop telescope. It’s a great little scope for viewing the Moon, planets, and even many brighter deep sky objects like the Messier Objects. Since it is not computerized, you’ll need a sky chart to help you navigate to viewable objects (See last paragraph). The same scope can also be purchased on an equatorial mount for those that may prefer a little more advanced setup. Orion and other manufacturers offer other scopes in this price range, but there are tradeoffs in ease of use and quality.

Between $200 and $400 - There are several scopes you might consider in this price range, depending on whether you require computerized object location. If you think you can learn the night sky well enough to find its treasures, you can get more viewing capability (larger aperture) if you forego a scope with “Goto” capability. For example, you can buy a 6-inch SkyQuest Dobsonian scope for $260 plus tax and shipping whereas a Meade ETX 80 (3-inch) tripod mounted Goto scope would cost you $280 plux tax and shipping. A 4.5-inch Goto scope will cost you about $400 plus tax and shipping. Remember, the larger the aperture, the brighter objects will be.

If you have $550 to spend, I would recommend the Orion SkyQuest XT6i Intelliscope. This is a 6-inch Dobsonian telescope with a computerized Object Locator. This is not a Goto scope, but is what we call a “Push To” scope. The object locator tells you how to position the scope left and right, up and down to find objects after you’ve aligned it on two bright stars. It requires you to be familiar enough with the night sky to identify and move the scope to two bright stars for the alignment process.

If you have between $600 and $900, I would recommend the Orion XT8i or the XT10i. These two scopes are larger versions of the Intelliscope. The obvious difference is cost and size of the objective mirror. Both give you a tremendous amount of light gathering capability for your money. The XT10i was my first scope and is still my primary telescope. When I step up to a larger scope this next year, I plan to keep my 10-inch. I can easily move it from the front door out into the yard, fully assembled, for a quick look at the night sky. The Object Locator helps me find deep sky objects under the light polluted skies here in Vegas. I wouldn’t recommend a scope any larger than the 10-inch Intelliscope as your first scope. Anything bigger becomes more difficult to transport and setup.

As you can see, it doesn’t require a huge budget to get started in amateur astronomy. There is a  starter system that will fit almost everyone’s budget. Now, that doesn’t mean that you can’t put a lot of money into this hobby. As you observe and become more involved in this great hobby, there will be accessories and upgrades that will entice you to spend additional dollars. And beware the dreaded bane of amateur astronomers the world over - Aperture Fever - the absolute need for a larger telescope.

One last thing, before I close. There are some supplemental accessories you should consider as part of your starter kit. These include a set of binos mentioned above, a star chart - either free from Skymaps.com or the Pocket Sky Atlas - for locating popular deep sky objects, and a red-lens flashlight to provide light for seeing your star chart without destroying your night vision.

Hopefully, these recommendations will provide a little

Looking East in December
By Rob Lambert

In the short time I’ve been an amateur astronomer, December’s evening skies have quickly become my favorite for early evening observing.  As the sky darkens after sunset, some of my favorite heavenly targets come into view. The first open cluster I learned to recognize, the Pleiades (M45), rises almost due east. This cluster is easy to locate, even in the light polluted skies of Las Vegas. Directly below it is the bright star Aldeberan in Taurus, the bull.  At first, Taurus isn’t easy to picture in the sky, but if you locate Aldeberan and the Hyades cluster associated with it, you have located the bull’s head. Aldeberan is one of the bull’s eyes and point of the “V” in the cluster is his nose. The tops of the “V” point toward the stars that represent the tips of the bull’s horns.

Following Taurus from the horizon is my favorite constellation, and next to the Big Dipper, the most recognized constellation or asterism in the sky, Orion, the Hunter. It was the treasures in Orion that hooked me on astronomy. Most impressive is the Great Orion Nebula (M42), but other treasures lie in wait for those interested in seeing more than just the Messier Objects. The Horsehead and Flame Nebulae lie just north of Alnitak in Orion’s belt.  Further to the north lies the smaller and lesser know M78, a diffuse nebula. Orion also has some interesting stars.  The two most know are Betelgeuse (Orion’s right shoulder) and Rigel (his left knee or foot). These two stars are great stars for illustrating stars of different color. Betelgeuse is a giant red star while Rigel is a brighter smaller blue white star.

I use Orion to introduce people to the winter night sky. You can use Orion as a pointer to other constellations and stars. Drawing a line from Betegeuse through and beyond Meissa (Orion’s head) points you to Aldeberan and the Pleiades. Drawing a line from Mintaka (right star in Orion’s belt) through Betelgeuse points you to the constellation Gemini and its bright stars Castor and Pollux.  Another line from Alnitak through Meissa points you to the constellation Auriga and its bright star Cappella.  And a line from Mintaka along Orion’s belt through Alnitak points you to Canis Major and the Dog Star, Sirius.Take some time to become familiar with Orion and let it be your guide to other constellations.

Taurus (Click for larger image)

Understanding the Phases of the Moon
by Rob Lambert

One of the questions I am most frequently asked by the public is, “Why does the moon have different shapes?” If one has never studied the moon in any detail, this is an understandable question. And with the help of this diagram, I hope to shed some light on the subject.

It’s important to understand that while the earth is rotating counterclockwise (eastward) on its axis, the moon is revolving counterclockwise around the earth. And because the moon is gravitationally locked to the earth, we always see the same side or half of the moon from our earthly perspective.  The lunar halves that are in sunlight and dark are the hemispheres that face toward and away from the SUN respectfully, and are always changing as the Moon moves around the Earth. A New Moon occurs when the near side faces away from the Sun. A few days later the Moon is a Waxing Crescent, where the bright area, seen from our perspective, is getting larger. As the Moon moves around its orbit and the Earth-Moon line is at right angles to the Earth-Sun line, we see a Half Moon, which we call a Quarter Moon. As it continues around the Earth and the bright part of the Moon is larger than Quarter, but smaller than full, it is called a waxing Gibbous Moon. When the Moon is opposite the Sun, the lunar hemisphere that faces Earth is fully lit and known as a Full Moon. As the Moon continues around its orbit, it becomes a waning Gibbous, Last Quarter, and then Waning Crescent. Waning means getting smaller. It then becomes a New Moon and the cycle of phases starts over again.