Report for 2002-01-11

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

Astronomical Times

Sunrise: 7:51 am	Sunset: 5:19 pm
Astronomical Twilight Begins: 6:13 am	Astronomical Twilight Ends: 6:56 pm
Moonrise: 6:24 am	Moonset: 3:44 pm

Viewing Outlook

Space Weather Update

Hubble Vision

Thackeray's Globules in IC 2944 Strangely glowing dark clouds float serenely in this remarkable and beautiful image taken with NASA's Hubble Space Telescope. These dense, opaque dust clouds - known as "globules" - are silhouetted against nearby bright stars in the busy star-forming region, IC 2944. These globules were first found in IC 2944 by astronomer A.D. Thackeray in 1950.   Although globules like these have been known since Dutch-American astronomer Bart Bok first drew attention to such objects in 1947, little is still known about their origin and nature, except that they are generally associated with large hydrogen-emitting star-formation regions, called "HII regions" due to their glowing light of hydrogen gas.   The largest of the globules in this image is actually two separate clouds that gently overlap along our line of sight. Each cloud is nearly 1.4 light-years (50 arcseconds) along its longest dimension, and collectively, they contain enough material to equal over 15 solar masses. IC 2944, the surrounding HII region, is filled with gas and dust that is illuminated and heated by a loose cluster of O-type stars. These stars are much hotter and much more massive than our Sun. IC 2944 is relatively close by, located only 5900 light-years (1800 parsecs) away in the constellation Centaurus.   Thanks to the remarkable resolution offered by the Hubble Space Telescope, astronomers can for the first time study the intricate structure of these globules. The globules appear to be heavily fractured, as if major forces were tearing them apart. When radio astronomers observed the faint hiss of molecules within the globules, they realized that the globules are actually in constant, churning motion, moving supersonically among each other. This may be caused by the powerful ultraviolet radiation from the luminous, massive stars, which also heat up the gas in the HII region, causing it to expand and stream against the globules, leading to their destruction. Despite their serene appearance, the globules may actually be likened to clumps of butter put onto a red-hot pan.   It is likely that the globules are dense clumps of gas and dust that existed before the massive O-stars were born. But once these luminous stars began to irradiate and destroy their surroundings, the clumps became visible when their less dense surroundings were eroded away, thus exposing them to the full brunt of the ultraviolet radiation and the expanding HII region. The new images catch a glimpse of the process of destruction. Had the appearance of the luminous O-stars been a bit delayed, it is likely that the clumps would actually have collapsed to form several more low-mass stars like the Sun. Instead they are now being toasted and torn apart.    The hydrogen-emission image that clearly shows the outline of the dark globules was taken in February 1999 with Hubble's Wide Field Planetary Camera 2 (WFPC2) by Bo Reipurth (University of Hawaii) and collaborators. Additional broadband images that helped to establish the true color of the stars in the field were taken by the Hubble Heritage Team in February 2001. The composite result is a four-color image of the red, green, blue and H-alpha filters.  Image Credit: NASA and The Hubble Heritage Team (STScI/AURA) Acknowledgment: Bo Reipurth (University of Hawaii)

Lunar Phase

The moon will be new Sunday morning. This is a great time to view. You can go DEEP, since the moon won't overwhelm those extremely faint targets. You can also view the moon itself, as it's relatively low brightness makes it less difficult to observe. You won't need any lunar filters or anything like that. To catch the moon though, you might have to wake up early. The moon is rising about 6:30. Look for a tiny sliver of a crescent moon low in the east just before sunrise. Checkout this awesome shot of a tiny crescent Moon by astro-photography wiz Jerry Lodriguss. I've mentioned this before, but.. if you haven't been to Jerry's site... you're really missing out. He does amazing work!

Planetary Report

Pluto, the 9th planet, is rising at about 4:55 am. At mag 13.93, Pluto is a tiny, faint little spec in a telescope... any telescope. It is currently almost 3 billion miles from Earth. It's size varies between 0.11" and 0.065" and it's brightness between mag 13.6 and mag 16. Mag 13.6 is pushing the limits of a 6" just to detect it, while mag 16 is doing the same to a 16".   As the accompanying Hubble Space Telescope image shows, imaging Pluto is tough.

Venus is rising about 8:00 am, but, this is almost exactly the same time as the sun... Still shining at mag -3.92 Venus is being completely overwhelmed by the Sun which shines at mag -26.74. Venus will return as the Evening Star late in the winter and into the spring. Checkout this cool image of Venus taken by Brian Colville of the Maple Ridge Observatory.

Neptune, the 8th planet, is rising around 8:50. Shining at mag7.98, Neptune is a relatively easy target. However, at only 2", it displays absolutely no surface detail. Almost star-like in binoculars, it shows it's beautiful blue color in telescopes. Neptune gets this beautiful blue coloring from a layer of Methane in its upper atmosphere. Located almost 3 billion miles from Earth, Neptune has a huge circular orbit -- taking just over 164 years to orbit the Sun. In fact, Neptune's orbit varies by less than 1% from circular. Neptune has a couple of other claims to fame... It has the fastest wind speeds in the solar system with gust at almost 1500 mph. Similar to Jupiter, it is categorized as a gas giant. Neptune is roughly 17 times more massive than the Earth. In another similarity to Jupiter, Neptune has a  Great Dark Spot. William Herschel is credited with the discovery of Neptune in 1781. However, it had been recorded in several catalogs as a star as far back as 1690.

Mercury is rising at about 9:05 am. This is about 65 minutes after the sun rises. You know what that means??? Yup. Mercury will be visible "for a while" in the western sky just after sunset. Have you found it yet? Mercury should be an easy target now. But you'd better hurry. Mercury has already started to slide back towards the sun. Last week it was rising about 9:10. Next week it will rise at about 8:40. Now's your chance. Get out there in view Mercury. Then.. mark it off your list of objects. It's not the most impressive object in a telescope, but... you've got to see it all :) Mercury is currently spanning 5" and shining at mag-0.70.  The accompanying image shows the incredible amount of meteor bombardment which Mercury has gone through in its history. Since Mercury has no atmosphere, the marks of each and every strike are still visible on the planets surface.

Uranus, the 7th planet, is rising at 9:40. Shining at mag5.91, Uranus is a relatively easy target. However, this is another tiny planet at only 3".  It simply displays absolutely no surface detail. It does however show it's beautiful aquamarine color. Uranus also gets its beautiful coloring from a layer of Methane in its upper atmosphere. Located almost 2 billion miles from Earth, Uranus has a huge orbit -- taking just over 84 years to orbit the Sun. It is categorized as a gas giant as is Jupiter, Saturn and Neptune. Uranus is roughly 14 times more massive than the Earth. Discovered by William Herschel in March of 1781, Uranus was the first planet to be "discovered". All the others are plainly visible, and hence have been known since antiquity. The name Uranus was suggested for mythological reasons. Since Jupiter was the father of Saturn, it made sense to name the next planet out Uranus -- the father of Saturn.

Mars is rising in the southeast around  10:55 am. The Earth continues to pull away from Mars in it's orbit. In fact, the distance between the two planets has grown from about 40 million miles this summer to almost 140 million miles. This has cause Mars' apparent diameter to shrink. It is currently down to a measly 6" as compared to its 21" in June. It has dimmed significantly as well - currently shining at magnitude 0.86 down from -2.4 in June.  Mars will return for an even better pass in 2003. In the mean time, we can live vicariously through the works of astro-photographers like Al Kelly, who takes some of the most amazing astro-images that I have ever seen. If you haven't checked out his site, I'd highly recommend it. He has many awesome planetary and deep sky image that'll blow your mind.

Saturn joins us now about 2:20 pm. Look for Saturn in the east-northeast. Saturn has grown to an an impressive 20" -- this is almost as large as it ever gets and is currently shining at magnitude -0.20 -- which is also close to the brightest it gets. NOW is your best time to view Saturn. It will stick around through the winter and into the spring, but.. it is close to its biggest and brightest RIGHT NOW.  The accompanying image The accompanying image shows Saturn with two of its many moons. Pretty cool, huh?  Saturn is, as mentioned above, a gas giant. This means that it is large and composed mainly of gas. How large? Well, Saturn is over 95 times more massive than the Earth and has a diameter that is more than 9 times that of the Earth. If you throw in the diameter of the rings, that number jumps to over 20 times that of the Earth. Wow! Checkout this beautiful image of Saturn by Al Kelly. Make sure you checkout Al's site. He has one of the most amazing deep sky image collections on the web.

Next, look for Jupiter rising around  4:20pm. Jupiter is the king of the Planets. It is more massive than all the other planets combined. In fact, Jupiter is over 300 times more massive than the Earth. Not surprisingly, Jupiter also has the largest moon in the solar system, Ganymede. Jupiter is currently shining at mag -2.70 and has grown to a whopping 47". This is as big as it will get during this pass and... just shy of it's maximum possible size of 50"..  Jupiter is the second most reflective (a quality know as albedo) planet in the solar system. Only Venus reflects more of the sun's light. Add this fact with Jupiter's immense size, and it's no wonder that Jupiter shines so brightly. Checkout this beautiful image by (who else :)  Al Kelly. You can see two of Jupiter's moons transiting the giant planet. One has also cast an inky black shadow on the surface. Wow!  Many of the features visible in this image are within the reach of modest amateur telescopes. Depending on the size of the telescope and the quality of your skies, you might even do better! In fact, on an amazingly steady night last fall, I did. I'll remind you again. You have to check out the tools section of the Utah Skies website for a cool java applet which depicts the relative position of the four major Jovian moons and their shadows. It's called JavaJup. I regularly refer to JavaJup to help plan my viewing sessions.

Constellation Report

Our Constellation Report is an easy way for people to become familiar with the nighttime sky. We’ll discuss myths associated with a particular constellation as well as describing the numerous deep sky objects residing within its boundaries. 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 move on to the constellation Orion. This is such an awesome constellation, so full of amazing objects that we're going ballistic on the images.  Orion is the nebula capital of the universe. It's a well known fact. Nebulae can be found, seemingly, in every image you'll ever see of Orion. This nebulosity is both the birth and afterbirth of stars. Without nebulae, there would be no star formation.

.	The image to the left is a wide angle shot of Orion by Jerry Lodriguss. Look how busy this constellation is. Bernard's Loop (the big "C" shaped object is really only visible in wide angle shots. Look at all the nebulosity. You could (and probably should) spend days observing in Orion.

Deep Sky Report

 

Ok, let's start things off with THE most amazing object in the whole sky. The one... the only... The Orion Nebula - M42(mag3.7) This "birth place of stars" shows more detail, more color, more everything.. then virtually any object in the entire night sky. I'm having trouble coming up with enough superlatives to properly describe Orion. Checkout the awesome detail in this Robert Gendler image to the left. Wow! And... checkout this Subaru Telescope image of Orion in infrared. Awesome! Orion is visible to the naked eye just below the belt of Orion. It is actually in the center of Orion's Sword. Point a pair of binoculars towards Orion and the nebula instantly jumps into view as a gaseous object engulfing the neighboring stars. Moving up in aperture the views become incredible. In the 25" you see all kinds of 3-D structure and color.  The Orion Nebula is a huge, glowing cloud of gas. Predominantly made of hydrogen, the stars which you see inside the nebula were formed of this gas. And speaking of the stars. The bright stars at the center of the nebula are called the Trapezium. It is the light from these stars which lights the nebula and makes it glow. If you view no other object in your telescope of binoculars, make it Orion!

Moving on, barely...we come to another beautiful nebula, this time it's a Messier Object, M43(mag9.0). This bright diffuse nebula sits right next to M42, The Orion Nebula. In fact, it looks like an offshoot of M42. As such, it's just plain overwhelmed. That said, this would be a showcase object if it were located somewhere else in the sky.

Moving up Orion's sword we come to a beautiful Open Star Cluster NGC1981(mag4.6). Again, notice the nebulosity visible in the image. You'll find nebulosity throughout Orion. Sometimes just little bits and pieces, usually... overwhelming amounts of the most amazing patterns and shapes. This is a large loosely structured cluster. There are about 10-20 true cluster members, plus background stars.

Next up is The Horsehead Nebula . This nebula is actually created by dark matter between a bright background nebula and the viewer. This object is one of the most fascinating nebula in the sky, in fact, it was recently voted the "Most Popular" object by astronomers. Ok... you're excited, huh? Unfortunately, this object is very difficult to observe visually. So... enjoy the image :) This beautiful image was created by Al Kelly. Have you been to his site? If you haven't, you're in for a treat. Al has taken astro-photography to a new peak.

As if we hadn't seen enough spectacular nebulae, here's another to knock your socks off. This time it's NGC2024 - also known as the Flame Nebula. Check it out! It really does look like a flame.  This object presents a couple of challenges when observing. But... before you get discouraged, let me tell you that you will be able to overcome them all. First off is the bright star in the upper right of the image. This will help you to locate the nebula. Once you've found it though... it'll seriously hinder your viewing efforts. Your goal is to keep the star (Zeta Orionis) just outside your field of view. Next, use a nebula filter. They'll really help on this object. I've used both an OIII and an H-Beta filter. Both provide different perspectives on the object with the OIII being my personal favorite. This beautiful image was created by... yup.. you guessed it... Robert Gendler. Have you been to his site? If you haven't, you're in for a treat. Robert has taken astro-photography to a new peak.

Next we'll hit a related nebula NGC1977(mag5.0) I say related because this object is so close to Orion as to most likely be part of the same nebulous cloud. Due to the placement of stars in front, in back and inside the nebula, we get wildly varying views. Checkout this awesome Robert Gendler image. Is he something else, or what? To find NGC1977, simply move 1/2° north of M42.

Let's wrap things up with this weeks Utah Skies Challenge Object, diffuse nebula M78(mag8.0). We were having so much fun with objects in Orion that we decided to take it easy on you this week. M78 is a relatively easy object to find. I was looking at it in the 10" the other night. This is not the most impressive object when viewed in smaller telescopes (including the 10" :). But, under clear steady skies you'll find the view interesting. As I often do, I'd recommend varying magnification and trying some nebula filters if you have any. Each view will provide a piece of the puzzle you are trying to unlock. Good Luck!

If you are able to find all of these objects, you may be one of the few, the proud, the Deep Sky Obsessed. 
E-mail your findings to DeepSkyObservations@UtahSkies.org.

Light Pollution Update

Positive Steps in Summit County

Utah Skies has been hard at work trying to control the growth of poor lighting in our area. We have contacted numerous county officials and the media to try to bring this issue to resolution. Today, we'd like to pass on the following very positive Summit County update.

Summit County Planning Director Alison Weyher contacted Utah Skies on Wednesday and assured us that Summit County will act to preserve the areas night environment. In her e-mail, she said:

Let me take a minute to address your concerns and the steps the Community Development Department is taking to help resolve them.1. As you know, the County Commission has approved hiring an additional code enforcement officer. This position is currently being advertised and we hope to fill it by the end of the month. Having two enforcement officers will allow us to expand our enforcement actions, including light pollution. 2. I have asked the plans examiners to be sure that exterior lighting fixtures are "called out" in new residential construction plans. In the past we have not conducted a thorough review of the exact specifications of the exterior fixtures. This should help us eliminate some of the violations before they occur.3. Building inspectors will also examine the exterior fixtures as part of the finish inspection. While it is difficult to determine the amount of light coming from a fixture during daylight, the inspectors will be able to check wattage and compliance with the approved drawings. We have also purchased a new light meter to help ascertain accurate readings. Last night I was pleased to see the [Utah Winter] Sports Park turned off their lights. And Home Depot's lights were turned off at ll:00pm as they had promised.  We've ordered new lights for the exterior of the Richins [county library] Building and lowered the fixtures. This is an issue we take seriously and I believe we are working diligently towards a resolution. 

Utah Skies applauds these efforts. We feel that this is a serious quality of life issue and are glad to see the county proactively protecting the night environment. 

Checkout the Light Pollution Section of the Utah Skies website at www.UtahSkies.org for more information on the harmful effects of improper lighting or for ideas on how to improve your lighting. Please contact us with any questions you may have or to Volunteer to help us in the fight to curb light pollution.

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

 

Stay up to date on astronomical happenings by regularly checking the Utah Skies website at http://www.UtahSkies.org

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