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Your Daily Dose of Astonishment

By Diane K. Fisher

  
  
The January 20, 2013, Astronomy Picture of the Day is one that might fall into the “quirky” category. The object was found at the bottom of the sea aboard a Greek ship that sank in 80 BCE. It is an Antikythera mechanism, a mechanical computer of an accuracy thought impossible for that era. Its wheels and gears create a portable orrery of the sky that predicts star and planet locations as well as lunar and solar eclipses.
Click image for larger view
As a person vitally interested in astronomy, you probably have the Astronomy Picture of the Day website at http://apod.nasa.gov set as favorite link. APOD has been around since practically the beginning of the web. The first APOD appeared unannounced on June 16, 1995. It got 15 hits. The next picture appeared June 20, 1995, and the site has not taken a day off since. Now daily traffic is more like one million hits.

Obviously, someone is responsible for picking, posting, and writing the detailed descriptions for these images. Is it a whole team of people? No. Surprisingly, it is only two men, the same ones who started it and have been doing it ever since.

Robert Nemiroff and Jerry Bonnell shared an office at NASA’s Goddard Space Flight Center in the early-90s, when the term “World Wide Web” was unknown, but a software program called Mosaic could connect to and display specially coded content on other computers. The office mates thought “we should do something with this.”

Thus was conceived the Astronomy Picture of the Day. Now, in addition to the wildly popular English version, over 25 mirror websites in other languages are maintained independently by volunteers. (See http://apod.nasa.gov/apod/lib/about_apod.html for links). An archive of every APOD ever published is at http://apod.nasa.gov/apod/archivepix.html. Dr. Nemiroff also maintains a discussion website at http://asterisk.apod.com/.

But how does it get done? Do these guys even have day jobs?

Dr. Nemiroff has since moved to Michigan Technological University in Houghton, Michigan, where he is professor of astrophysics, both teaching and doing research. Dr. Bonnell is still with NASA, an astrophysicist with the Compton Gamma Ray Observatory Science Support Center at Goddard. APOD is only a very small part of their responsibilities. They do not collaborate, but rather divide up the calendar, and each picks the image, writes the description, and includes the links for the days on his own list. The files are queued up for posting by a “robot” each day.

They use the same tools they used at the beginning: Raw HTML code written using the vi text editor in Linux. This simple format has now become such a part of the brand that they would upset all the people and websites and mobile apps that link to their feed if they were to change anything at this point.

Where do they find the images? Candidates are volunteered from large and small observatories, space telescopes (like the Hubble and Spitzer), and independent astronomers and astro-photographers. The good doctors receive ten images for every one they publish on APOD. But, as Dr. Nemiroff emphasizes, being picked or not picked is no reflection on the value of the image. Some of the selections are picked for their quirkiness. Some are videos instead of images. Some have nothing to do with astronomy at all, like the astonishing August 21, 2012, video of a replicating DNA molecule.

Among the many mobile apps taking advantage of the APOD feed is Space Place Prime, a NASA magazine that updates daily with the best of NASA. It’s available free (in iOS only at this time) at the Apple Store.

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
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Tackling the Really BIG Questions

Astro ImagingBy Diane K. Fisher

  
  
Clusters of galaxies collide in this composite image of “Pandora's Cluster.” Data (in red) from NASA's Chandra X-ray Observatory show gas with temperatures of millions of degrees. Blue maps the total mass concentration (mostly dark matter) based on data from the Hubble Space Telescope (HST), the European Southern Observatory's Very Large Telescope (VLT), and the Japanese Subaru telescope. Optical data from HST and VLT also show the constituent galaxies of the clusters. Such images begin to reveal the relationship between concentration of dark matter and the overall structure of the universe.
Click image for larger view
How does NASA get its ideas for new astronomy and astrophysics missions? It starts with a Decadal Survey by the National Research Council, sponsored by NASA, the National Science Foundation, and the Department of Energy. The last one, New Worlds, New Horizons in Astronomy and Astrophysics was completed in 2010. It defines the highest-priority research activities in the next decade for astronomy and astrophysics that will “set the nation firmly on the path to answering profound questions about the cosmos.” It defines space- and ground-based research activities in the large, midsize, and small budget categories.

The recommended activities are meant to advance three science objectives:

Deepening understanding of how the first stars, galaxies, and black holes formed, Locating the closest habitable Earth-like planets beyond the solar system for detailed study, and Using astronomical measurements to unravel the mysteries of gravity and probe fundamental physics.

For the 2012-2021 period, the highest-priority large mission recommended is the Wide-field Infrared Survey Telescope (WFIRST). It would orbit the second Lagrange point and perform wide-field imaging and slitless spectroscopic surveys of the near-infrared sky for the community. It would settle essential questions in both exoplanet and dark energy research and would advance topics ranging from galaxy evolution to the study of objects within the galaxy and within the solar system.

Naturally, NASA’s strategic response to the recommendations in the decadal survey must take budget constraints and uncertainties into account.

The goal is to begin building this mission in 2017, after the launch of the James Webb Space Telescope. But this timeframe is not assured. Alternatively, a different, less ambitious mission that also address the Decadal Survey science objectives for WFIRST would remain a high priority.

The Astrophysics Division is also doing studies of moderate-sized missions, including: gravitational wave mission concepts that would advance some or all of the science objectives of the Laser Interferometer Space Antenna (LISA), but at lower cost; X-ray mission concepts to advance the science objectives of the International X-ray Observatory (IXO), but at lower cost; and mission concept studies of probe-class missions to advance the science of a planet characterization and imaging mission.

For a summary of NASA’s plans for seeking answers to the big astrophysics questions and to read the complete Astrophysics Implementation Plan (dated December 2012), see http://science.nasa.gov/astrophysics/. For kids, find lots of astrophysics fun facts and games on The Space Place, http://spaceplace.nasa.gov/menu/space/.

This article was provided by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
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Holloway Comet Observatory To Show Astrophotography

Comet C2001-Q4 (NEAT)
Comet C2001-Q4 (NEAT)
Copyright © 2001 - Mike Holloway
Comet 17/P Holmes
Comet 17/P Holmes – 11/16/2007
Copyright © 2007 - Mike Holloway
Mike Holloway, noted comet hunter and one of the most prolific digital astrophotographers of the Arkansas Oklahoma Astronomical Society will be showing a select group of his best work at the Fort Smith Art Center in downtown Fort Smith during the entire month of October, 2009.

These special photographic prints will be on display in the Staircase Gallery at the Fort Smith Art Center from Thursday, October 1, 2009 through Saturday, October 31, 2009.

Comet 17/P Holmes
Comet 17/P Holmes – 11/06/2007
Copyright © 2007 - Mike Holloway
Many of Mike’s images have been used by well-known scientific research groups in the US as a part of their on-going research efforts. Some of these images have revealed data and details about comets that the researchers could not get in any other way. Mike has honed his craft over a period of many years, and he has spent a great deal of effort, time, and funds in perfecting his techniques.

As an example of Mike’s collaboration with the scientific community, have a look at Mike’s story A Comet Caught By Its Trail on the Sky and Telescope web site. Mike is also a member of the CARA Project, or Cometary Archive for Amateur Astronomers. Mike’s images are found on a number of scientific web sites. Holloway Comet Observatory also maintains a Gallery on FotoTime that contains some great images by Mike.

To set up the showing, Mike has chosen eight different comets, starting in 2001, and he has been working to put this together since October of last year.  There are multiple images of a few comets and a 6-image set of Comet 17/P Holmes showing the evolution of the explosion.  Most are large prints of as large as 36” x 36”, so all the detail can be seen.  Mike has also put in a couple of Moon shots “just because I like them.” We’re sure we’ll like them as well.

It is Mike’s hope that this shows well for the community of amateur astronomers in this area and what can be accomplished.  Mike says it will hopefully show as art as well. This is a first for Mike, and as members of AOAS, we want to show him strong support from the amateur astronomy community and our wishes for his continued success.  So please attend the showing at some point in October if at all possible. The Fort Smith Art Center is located at 423 N. 6th Street in Fort Smith, AR, and can be reached at 479-784-2787.

The Arkansas Oklahoma Astronomical Society is proud to have Mike as a member, and proud of his valued contributions to both amateur astronomy and the scientific community.
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The Spike in the Ball - Saturn's Rings Edge-On

Astro ImagingThe first time that I saw Saturn's rings go edge-on after I began my sojourn into astronomy in 1984, it was during the latest disappearance of the rings back in 1996. I actually missed the days when the rings seemed to disappear, but I did see it when it looked like a spike through a tennis ball. So odd seeing the rings like that.....what would Galileo have thought if he'd taken his first views of Saturn during one of these edge-on episodes and then watched as the rings re-developed over a three-to-five month period? Actually, Galileo DID see the edge-on event of 1612. Here are his own words from his notes. "I do not know what to say in a case so surprising, so unlooked for and so novel." So it says on the Astronomy Picture of the Day website image for August 1, 1995.
Don't miss your current opportunity to see Saturn's rings as they go "edge-on" this September 4. It is a view to behold! HST/NASA images
Two other comparison images from Hubble Space Telescope showing the 1996 edge-on event.
There is also a link on this page to learn more about the process of the rings going edge-on to our line-of-sight.

Well it's that time once again. Saturn now appears through virtually all telescopes as a tennis ball with a long spike through the center. Of course, the bigger the telescope and the more power you're able to apply to the view, the better you'll see it. Any 60mm telescope at about 40X to 50X will do. Just try to keep it as steady as you can if it has the conventional "cheapie" tripod and eyepieces. But in just a few more weeks, that magical time will occur when the rings seem to disappear for a week or so before once again tilting the other way from our line-of-sight, and slowly tilt farther and farther each week until it again resembles the iconic image of Saturn and its magnificent rings that we're all used to. If you've never seen Saturn like this, you owe yourself the opportunity to do so and then watch carefully every time you're out viewing to see how much more the rings have grown since your previous time seeing them. Its a sight you might not ever forget.

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The Canary's Eyes

Astro Imaging
This incredibly detailed image of the Trifid Nebula helped me learn about an observatory on a mountaintop on the island of Tenerife in the Canary Islands of Spain. All images in this story used by permission from Daniel Lopez.
On a recent Astronomy Picture of the Day submission, I saw an incredibly detailed image of the familiar Trifid Nebula, M-20, in Sagittarius. Details in the image were better than almost any other image I'd ever seen of this object, and I did what I frequently do....I started clicking on the links associated with this particular image. These are the words and phrases of text which we see in blue, each connected to certain types of information about the image. Some dealt with the facility which took the image, its astronomer, the imaging equipment, all sorts of varied information linked to the APOD of the day.

By clicking on these links, I learned about an observatory in a little-known corner of the world, where other images with similar fine detail are regularly produced by one of the resident astronomers, Daniel Lopez. I clicked on Mr. Lopez's name and promptly sent him an email to ask permission to use his images for this story. Within only a couple of hours, Daniel had replied to my query and had given me permission to use not only his pictures, but also other images from the Observatorio del Teide.
The IAC 80 telescope of the Observatorio del Teide. Its a 32" f / 11.3 Classical Cassegrain. Click here for a zoomable image of the IAC 80. Images used by permission.
I had discovered the Observatorio del Teide on the island of Tenerife in the Atlantic Ocean, located off the coast of northern Africa in the Spanish Canary Islands.


What incredible detail this image had. The dusty innards of the distinctive trisecting lanes show more fine resolution than most of us have ever seen. Surely, the telescope and camera that took this image must have been one of the world's larger instruments, using a mega-sized CCD camera, I thought, but I was SOOO, wrong!

I had until that time never heard of the IAC telescope (IAC being the Instituto de Astrofísica de Canarias). What amazed me was that this was a telescope of LESS than 1 meter in diameter! Its actually a .8m mirror, of a Cassegrain design with a focal ratio of 11.3. Translation, its a 32" f/11.3 Classical Cassegrain truss-tube OTA on a German Equatorial Mount. Simply amazing!

Click "Read More" for more technical details and more images
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Perfect Afocal Digital Astrophotography, Part 1

By Leonard Lynch

Figure 2
Top to Bottom - Coolpix 950, Coolpix 990, Coolpix 995, Coolpix 4500
A few months ago, I developed a renewed interest in astronomy and joined this fine club. I can''t express how fortunate I feel to have such a fine group of people to share an interest with. Every event that I have attended, from the Astronomy In The Park events last year, to the club meetings and star parties (that weren't rained out) this year, were like “Family Events.”

Figure 1
Example of Vignetting
One of my interests is astrophotography. I have an excellent Nikon 35mm camera and one day, I will buy the necessary attachments and take the time to figure out polar alignment. For now, Perfect Afocal Digital Astrophotography is my goal in life.

For the “newbies” that don't know the term, afocal astrophotography is simply the act of focusing an image in your eyepiece on the telescope, and then positioning a digital camera at the eyepiece and snapping away. The eyepiece focus, camera alignment, camera steadiness and camera/eyepiece proximity are all critical for good pictures, but I have seen some really good pictures taken by holding the camera to the eyepiece by hand.

I have a Sony CD500 digital camera, that takes wonderful pictures of everything terrestrial. When it comes to the afocal use of this camera, however, there is a problem. The lens moves in and out during focusing and manual zooming, and this, combined with the large diameter lens, causes a phenomenon called “vignetting” (pronounced vin-YET-ing.)

Vignetting means that the camera image looks similar to tunnel vision, that is, a small round image surrounded by blackness — like looking into a toilet paper roll. See Figure 1. I will not go into what causes this, as it is a little confusing to me, but I will try to work around it. Zooming the camera IN will eliminate most, if not all, of this in most digital cameras — but NOT with mine. Perfect Afocal Digital Astrophotography is not possible using this camera.

So, I searched the Internet to see how other like minded Amateur Astronomers were doing it. Most agree that the “only way to go” is with a Digital SLR camera. “Forget about afocal astrophotography, take your shots at prime focus, with a DSLR camera.”

Basically, like many of you, I cannot afford a thousand-dollar Digital SLR camera. I have too may other telescope accessories to buy, and recurring bouts of “aperture fever” to think about. Some of the most popular cameras for afocal astrophotography are the Nikon Coolpix 950, 990, 995, and 4500 model digital cameras. The 950 has a 2.1 mega-pixel chip and it is the oldest camera model. The 990 and 995 are 3.2 mega-pixel. The 4500 model is the newest model, with a 4 mega-pixel chip. The more mega-pixels, the more resolution the final picture will have. These cameras have small lenses that do not move externally when focusing and zooming, and have another feature that I like, a swivel in the middle of the camera so the LCD Screen can be adjusted to view the image when held at odd angles. Vignetting can be completely eliminated on these camera by zooming in slightly. Unfortunately, none of these cameras have been manufactured for several years. They are only available on the used market. See Figure #2.
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How do I take astronomical pictures?

Astro ImagingI have long wished to take pictures of the moon, planets, galaxies and nebulae with my telescope. How can I afford this, you ask? Isn't this extemely complicated? No! You can start taking astronomical pictures today.

You can use a simple film camera, or an inexpensive digital camera. Today a 4- or 5- mega pixel camera can be had for less than $200. With that said, you are probably saying "Prove It!" OK. Let's try a Kodak Easyshare Z730 camera. This one can be obtained from numerous online retailers for less than $170 and is capable of up to 64 second exposures. With this camera, and a $35 adapter that clamps on to your telescope eyepiece at one end and then screws in to your tripod mount hole on your camera, you are ready to go. With this set up you are able to photograph the moon and planets through your telescope.

You can do this with a telescope as small as 4.5 inches across. You also never need to buy film since you can keep reusing your digital film. I will follow up with articles showing you how to do more complex astro photographs with simple equipment. In my next article I will offer some simple examples. Have fun. That is what our hobby is all about. Any questions you are welcome to email me. Simply click on my byline above, and send me an e-mail.
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The Most Wonderful Hubble Image EVER!

Astro ImagingReleased on January 11, 2006, this Hubble Space Telescope image is the most impressive image ever taken of the "Great Nebula in Orion". The image covers a larger area of sky than any other HST image ever made, and the image has been painstakingly processed by "stitching" a large number of single images together to create this huge mosaic image. This nebula will be the highlight of our public observing nights on January 21st and 28th at Coleman Observatory. Come see this one for yourself!

Click image for larger view.
Isn't this a magnificent object? By way of AOAS's association with the NASA/JPL sponsored program known as Night Sky Network, we are among the first in the nation to offer up these images, links, and related details about this special Hubble Space Telescope Orion Treasury Project effort. This nebula is located in the constellation of Orion where it demarkates the middle star in the sword (see below) which hangs from the belt of the Mighty Hunter. It can be seen with binoculars, small telescopes, even the naked eye, but only the venerable Hubble Space Telescope could have given us this exceptionally detailed image.

Believe it or not, you can see a considerable amount of the detail captured in this image with your own eyes through our largest telescope here at Coleman Observatory.
The constellation Orion by one of the world's most reknowned and respected wide-field astrophoto- graphers, Akira Fujii of Japan.Click Here for original image and more Fujii/DMI images. Used by permission.
What our eyes have trouble seeing are the beautiful colors associated with this image. Our eyes don't work well on the colors of very dim objects. But CCD images are very capable of gathering all the various subtle colors seen here, and with special processing software, the colors can be made to stand out even more.

The colors themselves also reveal a great deal of scientific information about what chemical elements are present in the Orion Nebula. There's hydrogen associated with the reddish hues, and oxygen associated with green and some blue hues, as well as sulfur, calcium, silicates and other elements are detected through the combinations of the colors seen here. The darker brown and black areas are simply dust which in some places is dense enough to completely block the ionized light from the brighter parts of the nebula.

The main site where you'll find much more information and additional images about this exciting mosaic may be found at the Hubble site. There is also a site highlighting this image specifically for kids by clicking on Amazing-Space.

For a link to our downloadable PowerPoint associated with this image, and for the rest of the story, click READ MORE.
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AOAS Member Mike Holloway Contributes to Deep Impact

Astro ImagingMike Holloway observes and images from his home observatory north of Van Buren, Arkansas. With his 4" Takahashi FSQ-106 refractor and an SBIG ST-2000 CCD camera piggybacked on a Meade fork mounted SCT, he regularly submits images that garner world recognition. One of his most impressive feats to date is to have his image of Deep Impact Comet 9P/Temple1 from July 29, 2005 shown on the Deep Impact website. He has actually made quite a number of submissions to the overall effort on Deep Impact.
Periodic Comet 9/P Temple 1 on July 29, 2005. The comet has settled back down from it's flare-up just before, during and immediately after the Impactor craft slammed into the leading edge of Temple 1 on the evening of July 3-4 just three weeks earlier. Mike tracked on the comet making the stars trail in this image which appears in the Deep Impact website.


Mike loves comets! * That's what I said in the first article I wrote about him many months ago, and he hasn't slowed down one iota in his quest to image every available comet that swings around the Sun if at all possible, and there aren't very many that he misses. I just received this notice today about his image from July 29 appearing on the Deep Impact website and wanted to once again brag a little on the most successful astrophotographer in AOAS!

Observations of Temple 1 were made by amateur and professional astronomers from around the world during this historic first-of-its-kind mission from NASA. The Deep Impact website lists some impressive numbers of observers as well as their inclusion of Mike's image which they chose to use for a comparison to another set of four images. (To go directly to this page) Click here

I believe that Mike Holloway is in the process of making quite a name for himself in the world of astrophotography. I encourage everyone to leave a comment on Mike's achievements by clicking on "comment" at the bottom of this story. Whether you're an AOAS member, or a visitor from another country, please help us all show how much we respect Mike's work and how proud we are that he's one of our own! Make a comment now.

*Click on that first statement to see my first article on Mike.

"Comets on the Doorstep...." Here is another AOAS web story with more images and LOTS of links to Mike's and other comet watchers imaging handywork from around the world. ENJOY!
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Comet Breakup!

Astro ImagingOn June 12th, 2005, as usual, I was imaging comets. I had two comets which I wanted and a third if possible before it became lost in the horizonal muck. I started with 9P/Tempel 1 and found a comet not changed. Hopefully the smack of the impactor will change that. I then slew to a new comet. C/2005 K2 was discovered on May 19th, 2005 (I think) and has been breaking the brightness rules ever since. The close position to Earth has the comet moving very fast and it never seems to be where it is listed to be. I took a series of images on 06/12/2005 and after combining found a small extention in the same area as the Ion tail was to be found.

http://fototime.com/B22278DAE63CCCF/orig.jpg

I asked some questions but received no response with these images. Then on the 14th in the afternoon the first reports that I saw started coming in of a possible split. It was early afternoon here so I started planning my attack. The Moon was a factor but after taking 23 - 45 second images and doing a combine I had what I was after. It was a real thrill to be able to image a comet in the process of splitting. To think that a 4" Refractor and ccd camera in Van Buren could record such an event just flips my trigger. Here is the comet fragmented from the 14th at about 10:30 pm local central time. Thanks, Mike Holloway

http://fototime.com/DE1E32878056371/orig.jpg

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