Report for 2001-12-21

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

Astronomical Times

Sunrise: 7:48 am	Sunset: 5:02 pm
Astronomical Twilight Begins: 6:09 am	Astronomical Twilight Ends: 6:41 pm
Moonrise: 12:25 pm	Moonset: 11:45 pm

NASA's Mission Control To Help Santa

Viewing Outlook

Hubble Vision

Hubble Peeks into a Stellar Nursery in a Nearby Galaxy NASA's Hubble Space Telescope has peered deep into a neighboring galaxy to reveal details of the formation of new stars. Hubble's target was a newborn star cluster within the Small Magellanic Cloud, a small galaxy that is a satellite of our own Milky Way. The new images show young, brilliant stars cradled within a nebula, or glowing cloud of gas, cataloged as N 81.  These massive, recently formed stars inside N 81 are losing material at a high rate, sending out strong stellar winds and shock waves and hollowing out a cocoon within the surrounding nebula. The two most luminous stars, seen in the Hubble image as a very close pair near the center of N 81, emit copious ultraviolet radiation, causing the nebula to glow through fluorescence.   Outside the hot, glowing gas is cooler material consisting of hydrogen molecules and dust. Normally this material is invisible, but some of it can be seen in silhouette against the nebular background,as long dust lanes and a small, dark, elliptical-shaped knot. It is believed that the young stars have formed from this cold matter through gravitational contraction.   Few features can be seen in N 81 from ground-based telescopes, earning it the informal nick-name "The Blob." Astronomers were not sure if just one or a few hot stars were embedded in the cloud, or if it was a stellar nursery containing a large number of less massive stars. Hubble's high-resolution imaging shows the latter to be the case, revealing that numerous young, white-hot stars---easily visible in the color picture---are contained within N 81.  This crucial information bears strongly on theories of star formation, and N 81 offers a singular opportunity for a close-up look at the turbulent conditions accompanying the birth of massive stars. The brightest stars in the cluster have a luminosity equal to 300,000 stars like our own Sun. Astronomers are especially keen to study star formation in the Small Magellanic Cloud, because its chemical composition is different from that of the Milky Way. All of the chemical elements, other than hydrogen and helium, have only about one-tenth the abundances seen in our own galaxy.   The study of N 81 thus provides an excellent template for studying the star formation that occurred long ago in very distant galaxies, before nuclear reactions inside stars had synthesized the elements heavier than helium.   The Small Magellanic Cloud, named after the explorer Ferdinand Magellan, lies 200,000 light-years away, and is visible only from the Earth's southern hemisphere. N 81 is the 81st nebula cataloged in a survey of the SMC carried out in the 1950's by astronomer Karl Henize, who later became an astronomer-astronaut who flew into space aboard NASA's space shuttle.   The Hubble Heritage image of N 81 is a color representation of data taken in September, 1997, with Hubble's Wide Field Planetary Camera 2. Color filters were used to sample light emitted by oxygen ([O III]) and hydrogen (H-alpha, H-beta).   N 81 is the target of investigations by European astronomers Mohammad Heydari-Malayeri from the Paris Observatory in France; Michael Rosa from the Space Telescope-European Coordinating Facility in Munich, Germany; Hans Zinnecker of the Astrophysical Institute in Potsdam, Germany; Lise Deharveng of Marseille Observatory, France; and Vassilis Charmadaris of Cornell University, USA (formerly at Paris Observatory). Members of this team are interested in understanding the formation of hot, massive stars, especially under conditions different from those in the Milky Way.   Image Credit: NASA and The Hubble Heritage Team (STScI/AURA) Acknowledgment: Mohammad Heydari-Malayeri (Paris Observatory, France)

Space Weather Update

SUNSPOT WATCH: The Sun has been mostly quiet for two days, but that could soon change. Sunspot group 9742 is rapidly growing and poses a threat for strong solar flares. AURORA WATCH: The interplanetary magnetic field (IMF) near Earth is tilting south. This is a condition that lowers our planet's magnetospheric defenses against solar wind gusts and often sets the stage for geomagnetic activity. High-latitude sky watchers should remain alert for auroras.  Currently the Sun is peppered with spots, but none seem to pose a threat for very powerful eruptions. However, magnetic fields above sunspot group 9742 are growing more complex; the active region could become a source of flares in the days ahead. As always, keep an eye on www.Spaceweather.com for late breaking news.

Lunar Phase

The moon will reach first quarter tomorrow. This means that it rises around noon and sets around midnight. So... basically, you'll have easy access to the moon. It'll be fairly bright, so... it's beginning to impact deep sky observing. Of course for those of you in northern Utah... even the sun has been invisible lately. If you have a telescope, get it out and point it at the moon in the coming days. You will see an incredible amount of surface detail. Watching the moon grow from new to first quarter is quite interesting. Many "hidden" details can be seen during this period. The moon is an especially easy target to view. It's big. It's bright. You just can't miss it. You just might discover (or rediscover) a love for astronomy.  Checkout the accompanying image of the moon taken by Utah Skies' own Don Brown. This was taken last January right here in Park City.

Planetary Report

Saturn joins us now about 3:45 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 -0.34 -- which is also about as bright as 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! What a sweet pair of images taken by Ed Grafton. Checkout the amount of details he's captured in the disk of the planet! Look at how much detail he's captured in the rings. This is awesome work. Very Cool.

Next, look for Jupiter rising around  6:25pm. 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 -2.69 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. This accompanying images were taken by... Ed Grafton. Wow! Ed has again captured some amazing planetary details. If you haven't visited his website yet... what are you waiting for. This guy is good! 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 Taurus the Bull. Taurus the Bull is easily spotted almost overhead. Its head is the Hyades, a beautiful V-shaped star cluster. His horns point outward from the V. Aldebaran is the red eye of the Bull as he charges down upon us.

Deep Sky Report

 

Ok, let's start things off with the first object in the Messier list, Supernova Remnant M1(mag8.0). Also known as the Crab Nebula, this is the object which started Messier's list. Supernova Remnant??? That's a new one.... You're right. We haven't visited one of these before. A supernova is the final stage in the life of a large star. Essentially, the star blows up when it runs out of fuel to keep the nuclear furnace burning. This particular supernova was seen by Chinese astronomers in 1054. It was so bright that it was visible during the day! Located about 1° to the northwest of mag3 Zeta Tauri, this object is pretty easy to find. Keep the star within the outer ring of your Telrad and you're there. You do have a Telrad... don't you :) Don't expect to match the detail captured in this beautiful image by Robert Gendler. This is the result of a long exposure by a truly gifted astro-photographer. In the eyepiece, The Crab appears as a soft, nebulous structure. As you increase aperture, you'll start to pull out more of these details... but... not the color. The eye simply isn't very sensitive to colors at low light levels.

Next we'll hit the most spectacular star cluster in sky, M45(mag1.2). Also known as The Pleiades or Seven Sisters, this is one of the most spectacular deep sky objects of any type. Easily visible to the naked eye from the most light polluted of areas, this beauty is breathtaking from darker skies with some form of optical aid.  The Pleiades look like a tiny version of the big dipper. See the accompanying image... I'm not kidding. Located in the vicinity of mag1 Aldebaran and mag0 Saturn, these are a few easy targets for you.   Notice all the nebulosity in and around the cluster? Does it look this way in your telescope or binoculars? From my viewing site (ok... from my driveway :) the stars were clear and bright. There was definitely some nebulosity that was directly visible. Using averted vision, I was able to detect considerably more. No.. not as much as in the accompanying Robert Gendler image. (That was created by combining several longer exposures.) But...certainly enough that you'd be sure without a doubt that you saw it. By the way.. I was viewing through my Orion Argonaut -- a 6" Maksutov-Cassegrain -- so this should be the case in most small to midsized telescopes. These telescopes provide nice sharp images. The only real drawback is that they take a while to reach thermal equilibrium. So, I have to put mine outside 30-60 minutes prior to viewing on really cold nights.

Moving on, we come to another beautiful open star cluster, The Hyades(mag0.5). Spanning over 5°, this is another easy naked-eye target. Checkout this sweet image of both The Pleiades AND The Hyades by Jerry Lodriguss. If you haven't been to Jerry's website... follow the link! This guy does amazing work! The Hyades is a rather loose star cluster made up of around 100 member stars. The brightest star in the cluster, Aldebaran, is not actually a cluster member... merely a bright foreground star.  The Hyades is a GREAT target for binoculars. As I mentioned above, it spans over 5°. This is much wider than a telescope can view. So... the only way to view the whole thing is to use a pair of wide angle binoculars. This of course presents you with an amazing view.  Actually, this pair of clusters is a great way to get started on deep sky observing. Both objects are easily spotted with the naked eye... so... there's no difficult searching involved. Both objects look great with minimal investment in optics. ANY telescope or binoculars will do. Check it out! This was another of my targets on Wednesday night. I preferred the view of the Hyades through my binoculars, a pair of 10x50's with a 7° field of view. Unless you have an extremely wide angle telescope, you'll probably feel the same way.

Let's wrap things up with this weeks Utah Skies Challenge Object,  Irregular Galaxy NGC1552(mag14). This faint little galaxy will put your deep sky searching skills to the test. Fortunately, it's pretty small -- 1.9'x1.4'. This raises it's surface brightness to a whopping mag 13 per arcmin2. Not exactly blazing, but it should be within the reach of an 8"-10" telescope. While you're there (you did find it... didn't you :) Anyway... While you're there, see how many of NGC1552's neighbors you can find. As the accompanying image shows, there are a handful of faint neighboring galaxies to be seen as well. Aperture requirements will climb rather quickly for these. I'd throw in clear dark skies as well. 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

The True Cost of Outdoor Lighting

Anybody who's ever received an electric bill knows that lighting your home or business can be fairly expensive. Well, the bill you get from your power company is only a small portion of the total cost. True, you are the one who pays the utility company. But, society foots a substantial bill for other "hidden" costs.

For example: to power five 100-watt light bulbs from dusk to dawn for one year costs about $150. Yup... $150 to light up the neighborhood every night for a year.
Now, let's look at the "hidden" costs

To produce the electricity to run those five lights from dusk to dawn the utility company must burn about one ton of coal. Hmmm.. You may already see where this is going.

Burning one ton of coal releases the following toxins into the environment:

• 6600 lbs of Carbon Dioxide - a greenhouse gas

• 50 lbs of sulfur dioxide - a prime ingredient in acid rain

• 30 lbs of nitrogen oxide - a ground level ozone

• trace amounts of Mercury - even the tiniest amounts are harmful to ones long term health and has also been linked to birth defects.

Many respiratory problems are caused by or intensified by these airborne toxins. How many of you suffer from, or know somebody who suffers from asthma? According to The Mayo Clinic, there are a number of factors which may increase the chances of developing asthma. High on their list was exposure to environmental pollutants. As if this wasn't bad enough, researchers at Johns Hopkins University found that death rates rose with increasing levels of particulate matter. This is probably not a surprise to anyone, but... to hear this from some of the world's premier medical researchers just drives the point home.

So. How are you feeling about your exterior lights now? 
We're using the same tired, old solutions to solve our problems. 
We have got to use our heads. 
We need to devise some new solutions. 

Lest you think we're only raising an issue and walking away...Let us throw out a few suggestions:

• Examine your goals. Not every situation requires lighting. Once you have determined a need for lights,
• Install full cut-off lights. These fixtures restrict light to the target area, making the most effective use of your lighting energy, enabling you to:
• Use lower wattage bulbs and still get the same "on the ground" illumination
• Install motion detectors. This will allow you to have an increased sense of security while at the same time consuming substantially less energy

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.

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

 

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

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