Report for 2002-01-18

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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: 5:26 pm
Astronomical Twilight Begins: 6:12 am	Astronomical Twilight Ends: 7:03 pm
Moonrise: 10:51 am	Moonset: 10:32 pm

Viewing Outlook

Space Weather Update

Solar activity is quite high again. There have been numerous solar flares detected in the last week or so. Let's hope one of these brings us some beautiful northern lights. Look at all the sunspots in this Spaceweather.com image. Several of the sunspots, especially 9773 and 9782 harbor twisted magnetic fields which could easily flare up. Let's hope so :)

Hubble Vision

A Cosmic Searchlight Streaming out from the center of the galaxy M87 like a cosmic searchlight is one of nature's most amazing phenomena, a black-hole powered jet of electrons and other sub-atomic particles traveling at nearly the speed of light. In this NASA Hubble Space Telescope image, the blue of the jet contrasts with the yellow glow from the combined light of billions of unseen stars and the yellow, point-like globular clusters that make up this galaxy.  At first glance, M87 (also known as NGC 4486) appears to be an ordinary giant elliptical galaxy; one of many ellipticals in the nearby Virgo cluster of galaxies. However, as early as 1918, astronomer H.D. Curtis noted a "curious straight ray" protruding from M87. In the 1950s when the field of radio was blossoming, one of the brightest radio sources in the sky, Virgo A, was discovered to be associated with M87 and its jet.   After decades of study, prompted by these discoveries, the source of this incredible amount of energy powering the jet has become clear. Lying at the center of M87 is a supermassive black hole, which has swallowed up a mass equivalent to 2 billion times the mass of our Sun. The jet originates in the disk of superheated gas swirling around this black hole and is propelled and concentrated by the intense, twisted magnetic fields trapped within this plasma. The light that we see (and the radio emission) is produced by electrons twisting along magnetic field lines in the jet, a process known as synchrotron radiation, which gives the jet its bluish tint.   M87 is one of the nearest and is the most well-studied extragalactic jet, but many others exist. Wherever a massive black hole is feeding on a particularly rich diet of disrupted stars, gas, and dust, the conditions are right for the formation of a jet. Interestingly, a similar phenomenon occurs around young stars, though at much smaller scales and energies.   At a distance of 50 million light-years, M87 is too distant for Hubble to discern individual stars. The dozens of star-like points swarming about M87 are, instead,themselves clusters of hundreds of thousands of stars each. An estimated 15,000 globular clusters formed very early in the history of this galaxy and are older than the second generation of stars, which huddle closer to the center of the galaxy.   The data were collected with Hubble's Wide Field Planetary Camera 2 in 1998 by J.A. Biretta, W.B. Sparks, F.D. Macchetto, and E.S. Perlman (STScI). The Hubble Heritage team combined these exposures of ultraviolet, blue, green, and infrared light in order to create this color image.  Image Credit: NASA and The Hubble Heritage Team (STScI/AURA)  Acknowledgment: J.A. Biretta, W.B. Sparks, F.D. Macchetto, E.S. Perlman (STScI)

Lunar Phase

The moon will reach first quarter on Monday 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. Best of all, you won't have to stay up late, or wake up early. The moon will rise around 10am and won't set until 10pm. What could be easier? Checkout this image. I took this image at the end of a viewing session. Clouds were just starting to roll in when I noticed this eerie site. Anyway... given the way the weather has been lately, it just might look like this :)

Planetary Report

Pluto, the 9th planet, is rising at about 4:30 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 8:05 am. This is five minutes after 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 8:25. 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 8:40 am. This is about 50 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 8" and shining at mag0.54.  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 9:15am. Shining at mag5.92, 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  10:40 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 0.92 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 1:50 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 -0.16 -- 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  3:45pm. 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 -2.67 and has grown to a whopping 46". This is just about 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 Auriga. This should be an easy constellation to find. You're probably familiar with several of it's neighbors and it's a fairly bright collection of stars.

Checkout this awesome Jerry Lodriguss image of Auriga. Notice the detail he's captured. THIS is what Auriga would look like under truly dark skies. Jerry captured this image using a 85mm f/1.4 Nikkor lens for a 5 minute exposure. I've mentioned it several times, but... for any newcomers, you have to checkout Jerry's site. He does amazing work!

Deep Sky Report

 

Ok, let's start things off with the first of three Messier Objects residing within Auriga, Open Star Cluster M38(mag6.4). Estimates place this object about 4,200 light years distant. And, with a diameter of about 20', astronomers estimate an actual diameter of about 25 light years. M38 is believed to be about 220 million years old and contains a yellow giant of mag 7.9 as the brightest of its roughly 100 member stars.  While you're enjoying M38, see if you can spy tiny open cluster NGC1907. It's only minutes away, but it's diminutive appearance leads many to overlook it. When  you spot it, pump up the magnification a notch. This will make it the only object in the field of view, and allow for better observation.

Moving on about 2.5° to the southeast, we come to another fine Open Star Cluster Open Star Cluster M36(mag6.0). M36 is about 4,100 light years distant and spans approximately 12'. It has about 60 member stars, the brightest of which are about mag 9. Estimates of the age of M36 point to about 25 million years. This is quite young for a star cluster. M36 is the smallest of Auriga's Messier clusters.

Next up is yet another beautiful Open Star Cluster M37(mag5.6). M37 is the brightest of the 3 open clusters in Auriga. It is also the richest of the 3, containing roughly 150 member stars brighter than mag 12.5. Some estimates suggest upwards of 500 stars. Astronomers estimate its age at about 300 million years. This number is derived from the high number of red giant stars found in the cluster. Its distance is estimated to be between 3,600 and 4700 light years. Its diameter is 24' which corresponds to about 20 to 25 light years across. M37 is always my favorite stop in Auriga. The  bright, reddish star at it's center immediately becomes visible as my eyes lock on. It's quite a beautiful site.

Next we'll hit a cluster loaded with nebulosity, NGC1931(mag11.3) In fact, it's got so much nebulosity, you'll almost lose the cluster. Anyway... this whole object is kind of small... about 3'x3' so once you've found it, you'll want to crank up the magnification a bit. I'd also compare the views with and without various nebula filters.

Let's wrap things up with this weeks Utah Skies Challenge Object, IC405 also known as the Flaming Star Nebula. We've got another beauty from Jerry Lodriguss for you. Look at the amount of nebulosity he's captured. No wonder its called the Flaming Star Nebula. It really does look like the star is on fire. This object is a combination reflection and emission nebula. To best view the nebula, you'll want some aperture, dark skies and an H-Beta filter.  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 Canis Major.  

 

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

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