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Welcome to the Utah Skies Report.
We’re broadcasting this morning from beautiful Park City, "View-tah".

Weekend Viewing Conditions Outlook
Viewing conditions have been spotty at best all week. I got some amazingly sharp views the other night. Star images were textbook perfect.
With the weekend forecast to be dry, I'm hoping things will clear tonight and remain clear Saturday and Sunday night.

Astronomical Times
 

Sunrise: 6:26am	Sunset:6:42pm
Astronomical Twilight Ends: 4:54am	Astronomical Twilight Begins:8:14pm

Saturday evening brings us a new moon. This is typically the ideal time for deep-sky astronomical observing as there is no interference from the moon all night.

Planetary Report
In our planetary report today we focus on Saturn.
 

(This image was taken by a spacecraft passing Saturn. Notice how thin the rings appear. They are not the solid structure as was once thought, but are actually made up of countless particles of ice, dust and rock)

Saturn can be seen overhead shortly after sunset. To find Saturn, simply face towards the west and look up. The brightest object you’ll see is Jupiter, which we discussed last week. Saturn is about 10* to the west of Jupiter. To gauge the distance, it will be about the width of your outstretched fist. Shining at a visual magnitude of about 0, Saturn is one of the brightest "star-like" objects in the sky. Saturn orbits the sun at a distance of almost 1 billion miles. This is about 9 times the separation of the earth and the sun.

Saturn is the 2^nd largest planet. In fact, Saturn’s mass is greater than all the other planets combined excluding Jupiter. It weighs over 90x more than the earth and has a diameter over 9x larger than the earth.

Saturn’s most notable feature of course is its beautiful ring system, which is easily visible in a small telescope.
 

(The image to the left is readily achievable in amateur telescopes on nights of good seeing!  By this, I mean nights where the skies are clear, transparent and steady.  We regularly have such nights here in Utah. The high desert climate we live in is ideal for astronomical observation. Were it not for the cold stormy winters, there would undoubtedly be numerous observatories located in the state.)

A view of Saturn through a telescope is stunning. I always hear lots of oohs, aahs and "oh my gods" as people look into the eyepiece. "It really does have rings" is another typical comment. Yes, it does have rings, and in almost any telescope, they are clearly and prominently displayed. Saturn is currently tipped at roughly 25* to our line of site, making the rings stand out even more.

Saturn has dozens of moons. Several of these moons can be seen orbiting Saturn nightly in telescopes of modest aperture.

If you own a telescope or know someone who does, set it up this weekend! You’ll be glad you did.
Best views of the planet will be in the 150x and above range.
Remember to always set the telescope outside at least 30 minutes prior to observing this will ensure that the scope has reached thermal equilibrium and provide you with the best possible views your telescope is capable of delivering.

Constellation Report
Our Constellation report is an easy way for people to become familiar with the nighttime sky. We’ll discuss myths associated with the various constellations as well as describing the numerous deep sky objects residing in the area. No equipment is required to view the constellations, though a star chart can be quite helpful. This ease of observing makes constellations a natural place to begin your journey to the stars. This weekend we’ll focus in on the constellation Perseus.

 

Perseus To find Perseus, turn again to the west and look up. You should be staring straight up at Perseus. Perseus is high in the sky to the northwest. It sits just below or to the south east of the big W (No not the president) the other big W, the constellation Cassiopeia. I often describe Perseus as resembling the mathematical pi symbol. It has two sides running basically north/south capped with an arc running east to west along the upper or northern edge.  Perseus is full of many beautiful and interesting deep sky objects, which we’ll visit shortly. Mythical Perseus was one of the greatest of the ancient Greek heroes and the grandfather of the mighty Hercules. As was typical of Greek heroes, he was partially descendant of the gods. His father was reputed to be none other than Zeus himself.

Deep Sky Report
Our Deep Sky report examines Perseus in more detail.

First stop is Alpha Persei. At mag 1.8 this is the brightest star in the constellation Perseus. This star is a giant among stars, with a luminosity or brightness of over 4000 suns. Alpha Perseus lies directly in the Milky Way, appearing at the center of a beautiful star field. Point your binoculars at this object for a nice treat.

Stop number 2 is Algol or Beta Perseus. Algol is another bright star shining at about 100 times the brightness of the sun. The diameter of this giant is estimated at about 2.6 million miles. As a point of reference, the earth is about 8,000 miles in diameter. So we are talking really huge here.

Algol, also known as the “Demon Star” is what astronomers refer to as an eclipsing variable star. The brightness of Algol varies from magnitude 2.3 to 3.5 in only 4.5 hours. As each jump in magnitude represents a change in brightness equivalent to roughly 2.5x, Algol’s brightness fluctuation is about a factor of 3 . That means that Algol is 3 times brighter at its brightest than at its dimmest. This fluctuation occurs about every 3 days.

 

Double Cluster in Perseus

Moving on, we come to our next stop on the journey…the Double Cluster in Perseus. The Double Cluster is made up of the rich star clusters NGC 869 at mag 4.3 and NGC 884 mag 4.4.  NGC, for those who don’t know stands for New General Catalog.  The famous astronomer William Herschel created this catalog of deep sky objects back the late 18th century. The NGC contains over 13,000 deep sky wonders. The Double Cluster in Perseus is one of the most spectacular objects in the night sky. Visible to the naked eye just north of the body of Perseus, the Double Cluster is an impressive site in binoculars or a telescope. It resembles two handfuls of diamonds on a black velvet background. Each cluster contains dozens of visible stars. This is truly a must see object, so… dust off your telescope this afternoon as this object is at its best visibility early in the evening. Choose a low power eyepiece so that you can see both objects in the same field of view.

Next stop…M34 (mag5.2) A beautiful open cluster made up of about 80 or so bright stars. The famous astronomer Charles Messier discovered this object in 1764. Actually, the M in M34 stands for Messier. The Messier objects are a group of 110 objects that Messier included in his list of “non-comets”. Messier was a comet hunter. He logged the entries on this list so that if he saw one of them, he would know it was not a comet and hence could be ignored. While Messier found many comets in his career, it is for his list of non-comets that he is most famous. Back to M34. You will find M34 located between Algol and the beautiful double star Gamma Andromeda. From Algol, look about 5 degrees to the northwest. To help you gauge this spread, the width of 3 fingers held at arms length span approximately 5 degrees. Estimates place M34 at a distance of around 1500 light years. As a quick FYI, 1 light year is approximately 6 trillion miles. So 1500 light years translates into 9,000,000,000,000,000 (9 Quadrillion) miles. That’s a 9 with 15 zeros. Sounds pretty far away, huh? Actually this object is relatively close by astronomical standards. M34 resides within our own Milky Way galaxy. This is an easy object for a small telescope or binoculars.

NGC 891, a more challenging but worthwhile object in Andromeda lies 3* to the west-southwest of M34. This 10th magnitude spiral galaxy is seen exactly edge on. It has a dark dust lane running through it’s center. NGC 891 is listed at 43 million light years distant. This means that you are seeing this galaxy as it appeared 43 million years ago. Wow!

NGC 891

Moving back within the bounds of Perseus, we come to our next stop. M76 The Little Dumbbell Planetary Nebula (mag10.1).  This is the faintest object on the Messier list, but due to its small size ought to be relatively easy to find. Small telescopes will reveal this as a squarish smudge of light, while larger instruments should be able to pull out considerable detail. M76 features 2 prominent nebulous patches. In searching for this object, use a low power eyepiece and sweep the sky slowly and use averted vision.

What’s averted vision you ask? Averted vision allows the observer to pick up fainter objects than can be seen by looking at them directly. The technique is simple. Look away from the object under study while continuing to concentrate on it.  Averted vision is most effective if the observer looks at a point halfway from the center to the edge of the field of view. Essentially, you are utilizing some of the more light sensitive areas of your eye, enabling you to see fainter objects than could be view directly.

 

The California Nebula

Next stop is NGC1499, The California Nebula. This is a very large object with low surface brightness. Hence it can be difficult to locate. The California Nebula gets it name from it’s shape. I generally of resembles the state of California. While this might seem like a bit of a stretch, it does have a cutout right where the San Francisco bay is located. Your best chance at spotting the nebula will require dark skies and a nebula filter.

Our final stop in Perseus is our Deep Sky Challenge of the week. NGC1275. This mag 11.9 galaxy requires at least an 8” telescope just to glimpse it. Generally 12 to 16” or more is required for a good look.  With these larger apertures, you’ll notice that NGC 1275 is the largest and brightest of a rather large group of galaxies. These galaxies make up what is known as the Perseus Galaxy Cluster. Hubble Telescope images have revealed in excess of 3000 galaxies in this cluster. To find it, sweep 2 degrees east of Algol, and then ½ degree to the north. If you are able to find this object, you may be one of the few, the proud, the Deep Sky Obsessed. E-mail your findings to DeepSkyObservations@UtahSkies.org.

Light Pollution Update
Speaking of achieving the best possible views, we next move on to a topic that greatly hinders our views… Light Pollution.

(Can you find your town in this mess? Virtually every town and city in the developed world is represented in this picture. It is estimated that light pollution wastes in excess of $2 billion annualy in the United States alone!)

Generally speaking, light pollution is any light that does not fall upon its intended target. Light pollution takes many forms, from bright glowing skies which display few stars, to glare as we drive which reduces our visibility, to light trespass into our homes which keeps us awake at night.

Many people think "Hey,I live in rural Utah, I'm immune from this seemingly urban problem". Not any more!

Rapid growth in the area is threatening our view of the skies. Many homes now have multiple outdoor lights that are left on round the clock. Stores and businesses are illuminating large parking lots from dusk to dawn. The skies over Park City are beginning to resemble the skies over a small city, not a small rural mountain community. We need people to take a more active role in protecting and preserving our skies. The beautiful nighttime skies are part of what makes this a special place to live and vacation. In many parts of the country starry skies are a thing of the past.
 

(The Milky Way, as viewed in the late summer is one of the most awe inspiring views I have ever seen. One can sense of just how tiny our world is in the Universe)

It would be truly unfortunate if we lost this amazing treasure. Let’s not let this happen here.

What can be done to prevent this tragedy?

It’s actually quite simple. We need to begin to use lighting responsibly. That means using it only when and where it is needed. Don’t leave your lights on all night long. When everyone in the family is home, turn your exterior lights off. If you’re on the porch, turn the porch light on only. There is no need to have every light on the house turned on.

Using light responsibly also means using only as much light as is needed. Replace your 100-watt bulbs with 25-watt bulbs. You’ll still be able to see quite well and the exterior of your home will no longer have that harsh penitentiary look typically caused by overlighting. You’ll even save a couple of bucks in the process.

As an added benefit you’ll even be doing your share to protect the air we all breathe by not requiring the needless generation of more electricity. All in all I’d say it’s a "win-win" situation.

Next Weeks Report
Next week, we'll focus on the Constellation Orion and the beautiful Orion Nebula.

Closing

This "Star Cast" has been presented by Utah Skies, View-tah’s Astronomy Home. Utah Skies can be found on the World Wide Web at http://www.UtahSkies.org. Visit our site and discover the cosmos. We have numerous images of deep sky objects such as galaxies, nebulas and star clusters. We also have lots of astronomy-related information as well as links to other astronomy sites. Utah Skies is also your best source of information on light pollution.

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