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Welcome to the Utah Skies Report.
Brought to you from beautiful Park City, "View-tah".

The Week in Review
The first Utah Skies Star Party of the season took place last  Friday night and it was awesome. The evening was quite warm and the skies could not have been better. Dark, clear, steady. We kicked the night off with a quick view of the planets Mercury and Jupiter and then we went deep. The galaxy pair M81 & M82 started things off. We saw The Owl Nebula as well. Then we moved on to the Globular Cluster M3. It just about blew people off the ladder. Wow! Globulars rule! We cruised south to the Sombrero Galaxy M104. Then back up to the Hercules Cluster M13 and The Ring Nebula M57. Finally we took some views of Mars which was beginning to rise in the southeast.

Weekend Viewing Conditions Outlook

 

Astronomical Times

Sunrise: 6:07 am	Sunset: 8:40 pm
Astronomical Twilight Ends: 4:13am	Astronomical Twilight Begins: 10:34 pm
Moonrise: 4:09am	Moonset: 4:07 pm

Planetary Report

In our planetary report today we'll focus on a recent arrival on the scene. Fleet footed Mercury is rising rapidly in the western sky shortly after sundown. Mercury passed Saturn last week and Jupiter earlier this week to be the most easily visible planet in the early evening sky. Mercury will continue to rise until the 24th when it will begin its rapid descent. Mercury is the closest planet to the sun. Because of this, it has the smallest orbit of any of the planets. Mercury moves quickly from the nighttime sky to the morning sky and back, typically spending no more than a few weeks in either. Mercury is currently moving away from the sun and will be at its greatest distance (referred to as greatest elongation) on May 24th. So, you've got another couple of weeks to catch a glimpse. After that, Mercury will move too close to the sun to be seen.
	Venus is rising in the east about 3:15am. If you're an early riser, you may have noticed the intensely bright star to the east. Well, that's no star. It's the second planet, Venus. Blazing at a -4.5 magnitude, Venus is by far the brightest star-like object in the sky. I viewed Venus briefly just before sunrise the other morning. It's currently sporting a "half-moon" phase. Venus is so bright that it can actually be seen during the daylight hours if you know where to look.
Mars is rising in the southeast about 10:10pm. It has grown to an amazing 17" on it's way to almost 21" in Mid June. Mars reaches its Zenith, or highest point in the sky, at 2:30am. This is providing us with some of the best views of the planet in over a decade. If you own a telescope, take it out and use it, you'll be amazed at what you can see. Details comparable to the image at right are achievable on good nights. Modest telescopes will reveal normally invisible details including Martian clouds and icy polar caps.  Why is all this happening you ask? Well, let me tell you. Earth and Mars are converging at about 22,000 mph as the pair head for a close encounter next month. On June 21st Mars will lie about 40 million miles from Earth -- the nearest it's been in a dozen years. The planet is easy to pick out near the spout of the teapot-shaped constellation Sagittarius. Mars is bright and doesn't twinkle like a real star -- its steady copper-hued gaze is unmistakable.

Telescope Talk

The art and science of astrophotography has made great strides in recent years. Probably the single most important reason for this has been the advent of the CCD. CCD cameras allow astronomers, both professional and amateur, to image fainter objects than ever before. Today, many amateur images reach deeper and show more detail than images taken by the largest observatory telescopes just a generation earlier. The 2 CCD cameras shown above are among the most popular models available to amateur astronomers. The Santa Barbara Instruments Group (SBIG) ST series and the Apogee AP series provide high performance imaging at a reasonable price. As you'd expect from the leaders, their cameras work with most commercially available hardware and software. In addition, most of the deep sky images displayed in this report were captured using CCD cameras.

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 on the constellation Ursa Major.

Ursa Major is home to the most familiar asterism in the sky, The Big Dipper. Ursa Major, the Greater Bear, walks upright beneath the North Celestial Pole. The dominant figure, the Big Dipper (Plough in Britain), mark its hindquarters and tail (the stars, in order left to right, Dubhe, Merak, Phecda, Megrez, Alioth, Mizar, and Alkaid).

Deep Sky Report
The focus of our efforts this week will be the many deep sky objects in Ursa Major. 

Let's start things off with an interesting treat. Take a look at the handle of the Big Dipper and you'll see that it has a kink in it. This star is called Mizar (mag2.2) Look closely and you'll notice that Mizar has a faint companion. This is Alcor (mag4). Under decent skies, Alcor is readily visible. Now, if you have access to a telescope, point it in their direction. You'll notice that Mizar is in fact a double star itself. Cool, huh?  Mizar, at a distance of 78 light years from the Sun, and Alcor at 81 light years, while appearing to be a double star, are actually only an optical double. An optical double star is not a true double star where the components are gravitationally bound together and orbit around each other, but rather a chance alignment along our line of sight. I can't wait any longer... Let's Go Deep!

Ok, first off, lets visit one of the more well known galaxy pairs, M81 & M82 At magnitudes 6.8 and 8.4, these galaxies are well within the reach of the smallest telescopes and binoculars. Additionally, their close proximity typically places them within the same low power field of view. Whenever I view this pair, I'm always struck by how completely different the look. M81 is the bigger and brighter of the two. It displays the more typical spiral shape we have come to associate with galaxies. M82 on the other hand is clearly different. At first glance it might look like a spiral viewed edge-on, but there's more to it. M82 is clearly bisected. It appears split almost 60/40. It also display a bit of clumpiness near this point. Of the two, I always find myself drawn to M82. To find this pair, draw a line from Phecda (gamma) thru Dubhe (alpha) and continue for almost exactly the same distance. Its interesting to note that while these two galaxies appear so close, M82 is actually 12 light years more distant.

Moving on, we come to spiral galaxy M108 (mag 10.1). This odd shaped spiral galaxy looks somewhat like M82. It's core is not quite as bright, though it also has a somewhat mottled appearance. M108 is quite easy to locate sitting a mere 1 degree southeast of Merak (Beta)

Continuing along in a slightly more southerly direction for almost another degree, we come to a rather interesting planetary nebula, M97 The Owl Nebula (mag ??) I question the actual brightness because the 3 sources I checked each listed a different value. O'Meara in his book "The Messier Objects" listed it at mag 9.9. NGCView, a software tool I regularly consult listed it at mag 11.25 and Red Shift (discussed last week) listed it at mag 12. In any case, the Owl Nebula has two dark holes which appear to be eyes in the middle of a round face. The nebula itself is easy to find, but the eyes require dark skies. In a larger scope, you almost get the feeling that the Owl is looking at you as you study its intricate details. I have read reports of this being visible in 7x35 binoculars. This may be true, but I'd certainly throw as much aperture at this object as I could get my hands on. Once you spot this object, try using averted vision and see if you can pull some extra details out.
	Next we come to spiral galaxy M101 (mag7.9) also known as the Pinwheel Galaxy. This beautiful galaxy can be a bit harder than its magnitude 7.9 might indicate. The reason for this is that M101 covers are relatively large area. It's large size spreads out its brightness making it somewhat difficult to observe. To really get the most of this galaxy requires dark skies. Under moderately light polluted skies here in Park City, M101 is less than impressive. When viewed under the dark skies of the say the Uintas or the deserts of southern Utah, however, M101 is impressive. From dark skies its numerous arms become quite apparent. It looks as if it is tumbling through space with pieces falling off as it goes. M101 sits at the top of an almost perfect equilateral triangle with Alkaid and Alcor/Mizar. Now is a great time to view these objects as they are almost directly overhead when it gets dark.
Moving on we come to our Utah Skies Challenge of the week. Located 1 degree southeast of Phecda, is Barred Spiral Galaxy M109(mag9.8). This interesting galaxy looks almost like a Star Wars fighter craft swooping in for an attack. Its central core with clearly defined bar seems to wrap at the ends like the wings of a futuristic space craft.  If you are able to find these 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

Many people believe that they have a right to illuminate their property as brightly as they feel is "necessary". Well, like so many other rights, there are limits. Your right to illuminate ends at your property line. If lights from your property shine onto my property, you are violating my rights. We really need to show a bit of thought and consideration for what we are doing. There is absolutely no need to leave half a dozen lights on from dusk to dawn. It is extremely wasteful of both money and natural resources, causes the unnecessary release of pollutants into our atmosphere and often annoys our neighbors. Remember to think before you illuminate.

Next Weeks Report
Next week, we'll continue our journey through the cosmos and focus on the constellation Canes Venatici. 

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. While you're there, sign up to receive the free, fully illustrated Utah Skies Report. Many of our up coming star parties will only be announced to people on our e-mailing list. Sign up today.


 

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