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AVAS News &
Meetings |
Next AVAS Stargazing Opportunity
The AVAS will meet at the home of Jim Konowitz, about mid-way between Buena Vista and Salida with the primary evening being Friday, February 17th and a backup of Saturday, the 18th if the weather does not cooperate on Friday.
People with telescopes or those who would like to observe preparations can begin arriving around 7:00 PM and observing will start shortly after that as equipment is set up. Given the expectation of cold weather, breaks will be taken inside as needed to warm up.
The highlights for January include:
- Brilliant Venus is visible all month shortly after sunset in the southwest. Even a small telescope will show its moon-like phases.
- Jupiter will be high in the southwest in a very good position of observing.
- The Perseus Double Cluster (NGC869 and NGC884), two open star clusters located very close together will be to the north high overhead. Seen together in a telescope, they present a stunning sight with their bright, young and very hot blue stars.
- The Andromeda Galaxy (M31) and Dwarf Galaxy neighbor (M32) will also be very high in the west for ideal viewing.
- The Great Orion Nebula (M42), the brightest nebula in our sky, will be easily visible as it will be all winter.
- The asterism (a group of stars other than a constellation) Pleiades (M45), also known as the Subaru or Seven Sisters, is a beautiful naked eye open star cluster with some nebulosity (glowing clouds of dust and gas) that is visible once dark after sunset almost directly overhead. Using binoculars is actually the best way to view this cluster.
- The brightest star of all stars in the night sky, Sirius in the constellation Canis Major (The Big Dog) is also known as the Dog Star. Sirius appears to the southeast of the constellation Orion and rises around 7 PM early in the month and around 5 PM (although masked by sunlight until later) by the end of the month.
Everyone, of all ages and knowledge levels, with or without equipment, is always welcome to join in stargazing with AVAS. At the meeting everyone will have the opportunity to view a variety of deep sky objects such as other galaxies, open star clusters, globular star clusters, nebulae, and even some multiple star systems from binary stars up to sextuplet (6) stars. Meetings are informal and are held to provide a group stargazing opportunity. Telescopes will be set up for everyone to enjoy our night sky and members will provide descriptions and interesting facts about the celestial wonders being viewed.
If you are not already on our mailing list you can use our simple Contact Form to ask any questions about AVAS or to be added to the list for notification of the time and location of our next opportunity for group stargazing.
For more information you can contact Jim Konowitz at (719) 539-6839.
To get to Jim Konowitz’s house:
>From Salida:
Heading north on US 285, beyond the intersection of CO 291 and shortly after what was the Purple Sage restaurant the northbound highway changes from 1 lane to 2. At this point stay in the left lane, turn on your left signal, begin to slow down and watch behind you that if anyone is behind they notice you are turning. Make the left turn (on the road -- not the single driveway next to it) which is the combined County Roads 258 & 260.
Immediately after you make the left turn bear a hard right on CR 260. If you miss this turn or prefer having a left turn lane, continue north a couple of miles to the top of Dump Hill and make the first left on County Road 260 at the Centerville gas station. Then follow the directions as though you came from Buenie.
If you successfully made the left/then right turn onto 260 proceed north and just after 1.1 miles is Coyote Valley Road on your left. There are 2 large USPS neighborhood pedestal mail boxes on the left at the intersection.
Turn left/west on Coyote Valley Road. You will be making the 2nd left with the first (which you skip) being South Coyote Valley Road and the second being my driveway. Just past 0.7 miles from the county road is his driveway on the left at 12080 Coyote Valley Road. There is a single blue reflector at the drive. There is also a small sign "Hidden Springs" over the entry.
>From Buena Vista:
Go south on US 285. At the Centerville gas station turn right on County Road 260. As soon as you've made your right on 260 it immediately makes a hard left. Proceed south just past 1.4 miles to Coyote Valley Road. There are 2 large USPS pedestal mail boxes on the right at the intersection.
Turn right/west on Coyote Valley Road. You will be making the 2nd left with the first (which you skip) being South Coyote Valley Road and the second being his driveway. Just past 0.7 miles from the county road is his driveway on the left at 12080 Coyote Valley Road. There is a single blue reflector at the drive. There is also a small sign "Hidden Springs" over the entry.
About Arkansas Valley Astronomical Society Meetings
Arkansas Valley Astronomical Society monthly meetings are always open to the public. Weather permitting, we typically meet once a month on the Friday or Saturday closest to the new moon. This strategy allows for a dark sky and some predictability of when each meeting might be scheduled.
Your Feedback
To help the AVAS provide the most positive stargazing experience an anonymous survey has been created. You can respond to the survey using the following link: AVAS Stargazing Survey
Feedback, positive or negative, about AVAS is always appreciated. To submit any comments, please use our Contact Form. Since the Name field is required, it is optional as to whether you provide your real name. The other fields are optional.
Community Star Parties
We welcome inquiries from schools, community organizations and groups who may have an interest in our assisting you in conducting a “star party” as part of your activities. Feel free to contact us using our Contact Form for more information.
Need Help Using your Telescope?
If you or someone you know received a telescope or one of the newest stargazing instruments as a gift, or even if you have had one tucked away in a closet unsure about taking it out, AVAS members will gladly try to help you get started with your it if we can.
If you would like to have an opportunity to learn how to use a telescope that is new to you contact Jim Konowitz (719) 539-6839 or by using our Contact Form to initiate a possible get together.
Orientations are usually best conducted in a lit (daytime or indoors) environment. If your new scope is a Go To or computerized model it is always helpful to bring your scope's manual. If you do not have a copy of the manual check on the web to see if you can get a version.
Free Software for the Night Sky
If you have used astronomy related free software and would like to have it added to the information below please contact Jim Konowitz to share your experience.
The following software programs are available on the web and are free. They are quite different in both how they work and the information that they represent in the night sky. Each has different advantages and disadvantages but can help anyone with learning the about what is up there ane where it is.
As with any software for working with the sky, after downloading and installing it it is important to define your initial use parameters such as location and timezone. Until that is done, the information presented will not be very useful.
Halo Northen Sky (for Windows) presents entire the sky similar to the way star charts do. After setting the initial parameters it is relative simple to use. For most people, especially novices or those with limited computer resources, the Small Basic Package should be adequate. It is available at Halo Northern Sky Web Site.
Some of the many possible display formats are available as screen shots at Halo Northern Sky Screen Shots.
Stellarium (for Windows, Linux, Mac OS) presents the sky in a more realistic way, trying to make it appear as it does when you are outside looking up. It is a bit more complicated to use than Halo Northern Sky but has the advantage of displaying the sky in a way that is more like it naturally appears.
Most users will find the Default Catalog of Stars of over 600,000 objects to be adequate. Loading the additional available catalogs could significantly slow the program’s startup on slower or more resource taxed computers.
Stellarium is available at Stellarium Home Page. Screen shots of Stellarium are available at Stellarium Screen Shots.
The Time of Twilights
When we plan a stargazing session we obviously need to especially consider when the sky will be dark. Between sunset and maximum darkness we have 3 categories of twilight. Horizon in these cases is 90 degrees from zenith (directly overhead) and not the mountains to our west.
Civil Twilight is the time between sunset and the point where the sun is below the horizon 6 degrees. This is the period most of us consider to be twilight. At our latitude, Civil Twilight usually ends about 30 minutes after sunset and is referred to as Civil Dusk. When reasonable, this is the period we use for setting up our telescopes with some natural light still available.
Nautical Twilight is the time between the Civil Dusk (the sun is 6 degrees below the horizon) and the point where the sun is below the horizon 12 degrees. It is called "nautical" twilight because during this time most of the brighter, navigation stars become visible. Nautical Twilight ends about 1 hour after sunset with Nautical Dusk.
Finally we have Astronomical Twilight that starts with Nautical Dusk (the sun is 12 degrees below the horizon) and ends when the sun is 18 degrees below the horizon with Astronomical Dusk. At this point the sun is no longer effectively illuminating the atmosphere above us, or about 1.5 hours after sunset.
Typically we can start viewing the brightest objects such as the planets and brightest stars during Nautical Twilight. We have to be later into Nautical Twilight to begin viewing dimmer objects such as open star clusters. The dimmest objects like globular star clusters and nebulae generally need Astronomical Twilight to really be appreciated.
A convenient web site that provides the twilight times along with other related information is at Custom Sunrise Sunset Calendar - Colorado Location Selection.
What constitutes a "good" viewing night?
Of course, there is no exact answer to the question. However, there are some things that will help you see the heavens more clearly. And some simple checks you can make. If you want to see, photograph, or just explore the sky, there are some nights that are better than others. That is especially true if you are looking for faint objects, or if you would like to do some photography.
First, it should be dark. That means that the moon, especially if it is nearly full, should not be up. Many of us have to tolerate street lights, signs or fearful neighbors who feel better with the yard brightly lit. Those things are bad, but if the moon is shining also, almost everything else can be wiped out.
There are three technical terms astronomers use to describe the quality of conditions in the night sky. These are darkness, seeing and transparency. Darkness is just as it sounds. For instance, the moon or city lights degrade darkness. Seeing refers to how still the air is from the ground to the top of the atmosphere. Turbulent air makes for degraded seeing. Finally there is transparency. This refers to how clear the air is. Smoke and haze are some of the causes of degraded transparency.
AVAS is listed with a web site called the Clear Sky Chart. Our summer meeting site at Stone Bridge has been registered. The site not only goes into much greater detail about these terms, but also provides a chart of what the conditions are predicted to be at Stone Bridge. You can visit the Stone Bridge Clear Sky Chart at http://cleardarksky.com/c/StnBrCOkey.html?1 or by clicking =>Stone Bridge Clear Sky Chart.
There are a couple quick checks I use:
First, the stars should not be twinkling very much. Stars low in the sky may twinkle, but those higher up generally should not. If wind or rising warm air are stirring the atmosphere, the images will "dance", and you will not be able to see close star pairs, any detail of a planet or diffuse objects.
Second, the two stars that make the inside of the bowl of the Little Dipper, which are dimmer than 4'th magnitude, should be visible. Another clue is the nucleus of the Andromeda Galaxy, should be visible if someone shows you where to look (it is also 4'th magnitude, but is more difficult to see, since it is a diffuse patch, not a sharp point).
And What to do if There is Haze, Light Pollution, and Such?
There are still things to do unless it is clouded over. The bright planets, namely Venus, Jupiter and Saturn are worth looking at, if you can see them at all. Venus is always a bit of a washout since it is completely shrouded in clouds. But, what you can see is that it has phases -- a thin crescent when it is close to the earth, an almost full disk when it nears opposition (i.e. the other side of the sun), and everything in between. Jupiter and Saturn put on a good show almost any time you can see them.
A personal anecdote from our past President, Frank Snively: I didn't do much star gazing until I went out to California to attend graduate school. A friend of mine who knew his way around campus (he had been an undergraduate at Caltech, also) asked me, one evening, "What's that bright thing in the sky?" "I dunno." "Let's take a look", he said.
Like most graduates of Caltech, he had a collection of keys, and we went to the 1/10 scale model of the Palomar telescope, which had been built to support detail design of such things as the pointing and tracking system. It was always used as a Cassegrain, since only 20 inches diameter would not support a built-in observer's cage at prime focus.
Using the spotter scope, which needed cleaning badly, we located the bright object and looked in the main scope. There, with the rings glowing nicely, was Saturn. I still remember the thrill. And with the collecting area that comes with 20 inch diameter, it was quite bright. In later years, with lesser telescopes (my own is 8 inch diameter) I have also looked at Jupiter on many occasions.
And the moon is well worth looking at, as well. That is especially true several days before or after full moon. The craters near the terminator (i.e. the shadow line) are thrown into sharp relief by the sun which is close to the local horizon. Most of the larger ones have been named, and you can look at a diagram of the moon's surface to try to answer the question "What's that one called?" Of course, a good many smaller ones remain nameless.
A good many people stick a dark filter into the eyepiece of their scope when they are looking at the moon. It enhances the contrast, especially when the moon is nearly full. Note well, however, that there is no danger of actually harming your eye. The actual surface brightness of the moon is about the same as that of old worn pavement with the sun shining on it.
Something well worth watching
There is a very interesting web site you can take a look at. Dr John Dubinski, a professor at U. of Toronto, happens to have the largest "supercomputer" in Canada, and has used the facility to model the dynamic behavior of galaxies. No, he can't analyze all the hundred billion stars in something like our Milky Way or Andromeda, but he can track the behavior of, perhaps, several hundred thousand stars as they interact through gravity with each other. He has several simulations of colliding galaxies - note that the average separation of stars is so large that the galaxies pass through each other - and then "bounce" and ultimately form giant elliptical galaxies.
It is quite wonderful to watch.
The URL for the visual treats is:
http://www.galaxydynamics.org/gravitas.html
Rather than feel bad about inclement weather, and doing something desperate like watching TV, it is well worth using the computer for a look at several of the dynamic simulations.
The Sloan Digital Sky Survey Is Available
You might be interested in looking at a bit of the data from the Sloan Sky Survey. The data from the Sky Survey is processed at Fermilab in Illinois, and is available to the public. There is far too data much for any single astronomer or group to study in detail. The reduced data are available On Line, for public access. The URL is
http://www.sdss.org
There is a good bit of information on the web site which is accessable to the "normal" Mac and Windows users, which is most of us. I was personally reluctant to try to get into the UNIX oriented data files, since they would tie up a "home use" broadband connection (I use a cable modem, myself), and rapidly exceed the capacity of my Hard Drives. Maybe some day..
It would be nice to find something worth publishing in "Astrophysical Journal". The data are there. All we need is a dedicated (fast) home computer and plenty of storage capacity. Well a 1000 baseT Ethernet connection would be handy, also.
Two AVAS Astronomy Articles!
Frank Snively, past President of AVAS, discusses how we know if the color in a photo taken from space is accurate. Also, Jeff Beaty presents an interactive panorama of the surface of Mars as seen from the Spirit rover. Check out the Astronomy Articles Page.
A New Observatory Has Arrived In A Valley Near You
The Gunnison Valley Observatory is operational and open to the public!
The primary mirror of the telescope (about 30 inches diameter) is ground from a disk of low expansion glass, and is carefully mounted for vibration isolation and thermal isolation. The Cassegrain reflector is mounted on a number of steel posts which extend from the primary support. It is interesting to note that the Cassegrain position has a motor control - necessary because the thermal expansion of the support is quite different from that of the mirrors, and the telescope would go out of focus as the temperature changes.
The local promoters have made arrangements with a faculty member at the University of Dallas to procure CCD imaging and spectroscopic equipment, which will make the telescope useful for a variety of research programs.
For more information, use the link on the AVAS home page, to go to "coloradoskies.org" or click =>Gunnison Valley Observatory.
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Buena Vista Area Sky Chart
