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Open House Tonight! September 25, 2009

Posted by jcconwell in IYA 2009, telescopes.
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Rain or Shine! Come rotate the dome, and if the weather clears, which it looks like it will we will be looking through the 16″ telescope. There will also be other smaller  telescopes and giant binoculars. So come on by.

EIU Observatory

EIU Observatory

We’ve also had a lot of astronomy events last week.  Our thanks to Dr. Brian Field who packed the house with 88 people for last Thursday’s  IYA talk,  “When Stars Attack” .  Last Friday we had the faculty appreciation picnic and afterword, we opeded up the dome and had 98 faculty and staff, with their families, look at the majesty of Jupiter.

Wow… those are some big telescopes! July 18, 2009

Posted by pjhsci in Astronomy, Observatory, telescopes.
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Matthew Sanders has his blog at:   http://pjhsci.wordpress.com/

You know, most people think that the Hubble Space Telescope with its 2.4 meter mirror is the best window into the universe because it resides in orbit, has no atmosphere to mess with the view, and above all, it is almost always the only telescope that you hear about through regular media venues.  This will change within the decade.  There is a new breed of telescopes that are Earth-based that can deliver images ten times sharper than Hubble is capable of.  In the works are reflectors that will provide images up to 100 times sharper than that!

How we adjust for our shortcomings, being here on Earth and all…

Most of the largest scopes today use reflectors measuring 8-10 meters across that may be segmented into many smaller mirrors such as the Keck system of Hawaii.  Keck II Mirror showing segmentationThese scopes benefit not only from the fact that the mirrors can gather a large amount of light, but also the use of adaptive optics systems. (The AO system in the photo of Keck II is at the top of the photo partially housed on the frame skeleton along the right-hand side.)  These systems are what allow Earth-based telescopes to compensate for one of the plagues of astronomers on Earth:  the atmosphere,  more specifically, the turbulence within the atmosphere.  That turbulence is what makes the stars appear to twinkle.  AO systems reduce, if not eliminate, most of that issue.  The simplified version of how AO systems is rather neat.  A laser is fired from the telescope into a thin layer of sodium atoms that exists in the atmosphere, causing them to glow.  This glow is monitored by the AO system to adjust for the atmospheric interference more than 1000 times per second.  This technology turns distant stars from pretty, fuzzy-edged smears to clear, tiny points of light.  Without AO, astronomers could differentiate between objects that were 1/3600th (1 arc second) of a degree apart.  Now, using AO on current scopes like Keck, astronomers can identify multiple objects within that single arc second!

Wait, only an 8.4 meter mirror?  What is so special about that?!

Courtesy www.lsst.org/News/ 0501/050111.shtml
The LSST will provide a generous field of view to explore. Courtesy www.lsst.org/News/ 0501/050111.shtml

In August of 2008, under the football stadium at the University of Arizona, a spinning furnace cast the 8.4 meter mirror that is going to be the eye of the Large Synoptic Survey Telescope.  The LSST will be unique, not in the size of the mirror, but in the field of view it should provide.  Conventional scopes have a field of view of around 0.5° per side.  The LSST will provide astronomers a field of view that is 10° per side.  That means that the LSST can take images of the entire visible night sky over the course of a few days rather than months or years.  It will be located on a mountaintop in Cerro Pachón, Chile.  This will allow astronomers to observe objects and events at distances over 10 billion light years!  The ability to record the entire sky repeatedly and quickly will give astronomers the chance to build a motion picture of sorts of short-term events that are missed using conventional telescopes.  Over the course of many cycles, new near-Earth asteroids could be located, flares on dim stars could be identified, and perhaps some of the mysteries of dark matter and energy could be brought into clearer focus.  Innovative telescopes like the LSST could be the key to unlocking those riddles that drive astrophysicists bonkers with uncertainty.

Okay, how big are we talking here?

If one 8.4 meter mirror is good, why not use two?  The Large Binocular telescope on Mt. Graham in Arizona boasts two 8.4 meter mirrors that produce an effective light gathering ability of an 11.8 meter telescope.  With some of the new adaptive optics enhancements coming down the pipe, it is hoped that the LBT will have the effective ability of a 23 meter scope in a smaller package.
If one 8.4 meter mirror is good, why not use two? The Large Binocular telescope on Mt. Graham in Arizona boasts two 8.4 meter mirrors that produce an effective light gathering ability of an 11.8 meter telescope. With some of the new adaptive optics enhancements coming down the pipe, it is hoped that the LBT will have the effective ability of a 23 meter scope in a much smaller package.

There are two schools of thought on this matter:  single reflector or multiple reflectors.  The Large Binocular Telescope in Arizona uses a tandem mirror (Keck I and Keck II can be used in tandem, as well) to provide an image greater than the sum of its parts. (see sidebar)  These arrangements can be constructed in smaller spaces where area is at a premium.  A tandem system takes images from both mirrors and uses computer programs to combine the images, adjusts them with the AO system and produces a composite image.  Other multiple reflector systems are on the slate as well.  In 2018, it is projected that the Giant Magellan Telescope will be functional in Chile.  This composite telescope will utilize not two, but seven 8.4 meter mirrors to produce an image!  The Very Large Telescope array will use a total of eight reflecting units when fully operational.  There will be four 8.2 meter stationary units and four 1.8 meter moveable units to compile images.

This is really interesting technology, but really, just how large a single reflector telescope are astronomers trying to construct?  The Thirty Meter Telescope is to be located in either Chile or Hawaii and scheduled to be online in 2018, but that is small potatoes compared to another monster slated for 2018.

This image portrays the proposed European Extremely Large Telescope with its 42 meter reflector.  This giant is actually a scaled down version of the budget-crippled Overwhelmingly Large Telescope that was to utilize a 100 meter reflector!
This image portrays the proposed European Extremely Large Telescope with its 42 meter reflector. This leviathan is actually a scaled down version of the budget-crippled Overwhelmingly Large Telescope that was to utilize a 100 meter reflector!

The Extremely Large Telescope is just that; an extremely large telescope!  This 5500-ton reflector system will be housed in an observatory 80 meters tall and 100 meters in diameter.  The mirror will be a staggering 42 meters across… yes, 42 meters! Imagine the distance that our puny human optics will be able to penetrate into space with this behemoth as our tool!  What new worlds could we discover?  What origins of the universe could we unveil?  Just imagine what we will be able to see…

LBT Photo – www.kosmologs.de/
ELT Photo – www.spacedaily.com/

Information gathered from:

National Geographic, June 2009

European Space Organization

Bill Arnett’s Nine Planets.org

Five New Supernovae Before Breakfast June 15, 2009

Posted by jcconwell in Astronomy, telescopes.
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In a preview if the new superautomated survey telescopes that are appearing in the next few years…this from Palomar observatory. The venerable 48″ Schmidt telescope, the largest in the world, that was responsible for the grandfather of all surveys , the original Palomar sky survey has been automatated and given a  new life as the  48-inch Samuel Oschin Telescope.

Edwin Hubble using the 48" Schmidt Telescope

Edwin Hubble using the 48" Schmidt Telescope

An innovative sky survey has begun returning images that will be used to detect unprecedented numbers of powerful cosmic explosions-called supernovae-in distant galaxies, and variable brightness stars in our own Milky Way. The survey also may soon reveal new classes of astronomical objects.

All of these discoveries will stem from the Palomar Transient Factory (PTF) survey, which combines, in a new way, the power of a wide-field telescope, a high-resolution camera, and high-performance networking and computing, with rapid follow-up by telescopes around the globe, to open windows of discovery for astronomers. The survey has already found 40 supernovae and is gearing up to switch to a robotic mode of operation that will allow objects to be discovered nightly without the need for human intervention.

The Palomar Transient Factory is a collaboration of scientists and engineers from institutions around the world, including the California Institute of Technology (Caltech); the University of California, Berkeley, and the Lawrence Berkeley National Laboratory (LBNL); Columbia University; Las Cumbres Observatory; the Weizmann Institute of Science in Israel; and Oxford University.

During the PTF process, the automated wide-angle 48-inch Samuel Oschin Telescope at Caltech’s Palomar Observatory scans the skies using a 100-megapixel camera.

The flood of images, more than 100 gigabytes every night, is then beamed off of the mountain via the High Performance Wireless Research and Education Network¬-a high-speed microwave data connection to the Internet-and then to the LBNL’s National Energy Scientific Computing Center. There, computers analyze the data and compare it to images previously obtained at Palomar. More computers using a type of artificial intelligence software sift through the results to identify the most interesting “transient” sources-those that vary in brightness or position.

Within minutes of a candidate transient’s discovery, the system sends its coordinates and instructions for follow-up observations using the Palomar 60-inch telescope and other instruments.

Soon all of the steps in the process will be completely automated, including decisions about which transients merit a second look. When follow-up observations indicate that candidate transient detections show promise, a prioritized list of candidates is brought to the attention of astronomers from the PTF member institutions. Finally, an astronomer becomes personally involved, by performing detailed observations using telescopes such as Palomar’s 200-inch Hale Telescope, a Keck Telescope in Hawaii, or other partner telescopes around the world.

Upgraded 48" Oschin Telescope

Upgraded 48" Oschin Telescope

The PTF is designed to search for a wide variety of transient sources with characteristic timescales ranging from minutes to months, giving astronomers one of their deepest and most comprehensive explorations of the universe in the time domain.

“By looking at the sky in a new way, we are ushering in a new era of astronomical discovery,” says PTF principal investigator Shrinivas Kulkarni, MacArthur Professor of Astronomy and Planetary Science at Caltech and director of the Caltech Optical Observatories. “Nimble automated telescopes and impressive computing power make this possible.”

“No one has looked on these timescales with this sensitivity before. It’s entirely possible that we will find new astronomical objects never before seen by humans,” says Nicholas Law of Caltech, the project scientist for PTF.

Because it looks for anything changing in the sky, the PTF survey covers a vast variety of different astronomical targets. The wide range of the survey extends across the entire universe. Astronomers expect to discover everything from stars exploding millions of light-years away to near-Earth asteroids that could someday impact our planet.

Much of the survey’s time is spent searching for so-called Type Ia supernovae. These supernovae, formed from the explosion of a class of dead star known as a white dwarf, are very useful to astronomers because they can help determine the distance to galaxies located across the universe. Those distances allow astronomers to probe the origin, structure, and even the ultimate fate of the universe.

By operating more rapidly than previous surveys, PTF will also detect objects of a completely different nature, such as pulsating stars, different types of stellar explosions, and possibly planets around other stars.

PTF’s innovative survey techniques also have raised astronomers’ expectations of finding new, unexpected, astronomical objects.

The PTF already has found many new cosmic explosions, including 32 Type Ia supernovae, eight Type II supernovae, and four cataclysmic variable stars. Intriguingly, PTF also has found several objects with characteristics that do not exactly match any other objects that have been seen before. PTF astronomers are eagerly watching these objects to see how they change, and to determine what they might be.

The quantity and quality of incoming data have astonished astronomers working in the field. On one recent night, PTF patrolled a section of the sky about five times the size of the Big Dipper-and found 11 new objects. “Today I found five new supernovae before breakfast,” says Caltech’s Robert Quimby, a postdoctoral scholar and leader of the PTF software team. “In the previous survey I worked on, I found 30 in two years.”

Source: California Institute of Technology

Herschel telescope wakes up! June 14, 2009

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Hershel space  telescope opened its hatch that has protected its sensitive instruments from contamination, allowing  light collected by its  3.5m mirror to enter its supercold instrument chamber, or cryostat, for the first time The observatory’s quest is to study how stars and galaxies form, and how they evolve through cosmic time. The command sent on Sunday to fire two pyrotechnic bolts holding down the hatch was arguably the key moment in the European Space Agency (Esa) mission since the 14 May launch from Earth.

Herschel

For more information go to the BBC NEWS. Also see an earlier article form May’s Blog  here.

New Documentary “400 Years of the Telescope” Now Airing April 14, 2009

Posted by jcconwell in Astronomy, IYA 2009, telescopes.
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I was lucky enough to be at the   “400 Years of the Telescope” world premiere at Long Beach in January at the American Astronomical Society. It’s now being aired locally on PBS.

Tuesday, April 14 — 09:00pm on WILL-TV, with a reproadcast at Tuesday, April 14  —  09:00pm on WEIU. If your not in this region go to here for a local time.

Observatory Open House Tonight January 30, 2009

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It looks like it’s going to be clear! So on come out and view the wonders of the constellation of Orion. Beginning with M42 the Great Nebula of Orion! Viewing begins at 8:00PM

Hubble Back Online! October 30, 2008

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From the NASA news Center:

NASA’s Hubble Space Telescope is back in business. Just a couple of days after the orbiting observatory was brought back online, Hubble aimed its prime working camera, the Wide Field Planetary Camera 2 (WFPC2), at a particularly intriguing target, a pair of gravitationally interacting galaxies called Arp 147. The image demonstrated that the camera is working exactly as it was before going offline, thereby scoring a “perfect 10″ both for performance and beauty.

The two galaxies happen to be oriented so that they appear to mark the number 10. The left-most galaxy, or the “one” in this image, is relatively undisturbed apart from a smooth ring of starlight. It appears nearly on edge to our line of sight. The right-most galaxy, resembling a zero, exhibits a clumpy, blue ring of intense star formation. The galaxy pair was photographed on October 27-28, 2008. Arp 147 lies in the constellation Cetus, and it is more than 400 million light-years away from

Clear skies & 110 vistors last night. August 30, 2008

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My thanks to all the people who helped make EIU’s first observatory open house of the semester a success. 110 visitors saw Jupiter through the 16″ telescope last night! I saw some faces that were back for their second or third visit. When you do this in the center of Illinois the last Friday of every month, you may have to wait to get a clear sky. Most people are quite content, the first time, to talk astronomy and look at the big scope, instead of through it. And rotating a 10 foot dome just never gets old, no matter what your age!

My thanks to Tim McCollum for bring his science class and his 8″ scope. Thanks also to Dr. Tim Camden and John Pratte for bringing their big light buckets. Thanks also our Astro Club’s VP, Maggie McAvoy for running the tripod binoculars, and all the members of the EIU Astro Club. It takes more than one big telescope to make a star-party go.

Tim Camden, John Pratte, Tim McCollum

Tim Camden, John Pratte, Tim McCollum

Astronomy in Charleston, Illinois August 26, 2008

Posted by jcconwell in Astronomy, IYA 2009, Observatory, telescopes.
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The second day of class.

Welcome to EIU! For those interested, the Society of Physics Students and the Astronomy Club will be having a joint meeting and cookout this Wednesday at 6:00 PM, anyone interested just contact me through email.

Later on this week, on Friday August 29th, we will be having the first public open house at the observatory. Rain or shine, we’ll be there, and if the skies are clear the object for that night will be Jupiter. If you don’t know where the observatory is, you can download a map at: http://www.eiu.edu/~physics/observatory.php

Which bring me to the main part of this blog. What’s going on in Charleston for astronomy? Well, as I mentioned above, we have a observatory on campus, run bythe physics department. It has a 16″ Schmidt -Cassegrain telescope. Most of the time we don’t have an eyepiece in it, but a CCD camera. The camera is an SBIG8, with a filter wheel, for doing color pictures or photometry. When we aren’t taking pictures, we’re using our new spectrometer. Spectra is where much of our knowledge of the universe comes from. The whole place is run by myself and the students of the astronomy club, and our new astronomy option-physics majors.

If you look down to some earlier posts, you’ll see a picture of both the telescope and the outside of the observatory. But … that’s not all that is around !!

We are also lucky to have, just on the edge of Charleston, ARI, the Astronomical Research Instituite. This is a private observatory run by Robert Holmes. It has a 32″ and a 24″ telescope, with plans for a 50″ telescope. The major project there, is the NEO project, short for Near Earth Asteroid project. It’s the search for those large asteroids that have the potential to hit Earth. The wonderful thing about this is that high school teachers and students can become involved in this. If you’re a high school teacher that might be interested in getting your students involved go to:

http://ari.home.mchsi.com/neo_followup_project.htm

http://aer.noao.edu/cgi-bin/article.pl?id=258

For students out there interested in coming to Eastern to study physics an Astronomy here’s a picture

ARI’s 32″ telescope.

Clear skies, and I hope to see you Friday.

Looking through the telescope the wrong way. June 27, 2008

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Living in East-central Illinois means that when people visit the EIU observatory you have to contend with weather. At night, about half the time, it will be cloud covered and you just get to look at the telescope. If you come in the day its even worse. We can actual still see the football stadium light that are about 3000 feet away in the day.

On these occasions one of the things that I do is to lower the telescope and let people look down the tube and see the 16″ mirror, which acts like a really BIG makeup mirror. Since I have a Schmidt-Cassegrain telescope, with a front corrector plate, one of the thing people comment on is how DIRTY the front plate looks.

Don’t I ever CLEAN it!!!…….

Nope…. well not quite as often as you might think I should… and there’s a reason.

Most telescope lenses , and camera lenses, come with an anti-reflection coating, typically a coating of MgFl. You can tell when you look at it because it gives the lens a slight purple, or sometimes yellow color. The coating is put there to increase the transmission of light, to the eye or camera, by using the wave properties of light to eliminate reflection.

The coating is very thin, quite delicate, and can be easily scratched, and is expensive. Our 16″ telescope cost about $500 to get it recoated. So cleaning it is a very big project … distilled water…lots of care and can take several hours to make sure the dust doesn’t scratch the coating when it’s removed.

Also, you don’t need to do it very often. Even on a very dusty lens the light is only cut by a few percent. The dust on the lens is so much closer than what your looking at, the dust is out of focus, so you don’t notice it with your eye. A digital CCD camera is more sensitive, especially if the dirt is not uniform. We can compensate for that by taking what is called a “flat field” briefly, this is a photo through the telescope of the dirt! This is then digitally subtracted from the from any photo! Electronically cleaning it up.

So the short answer is I don’t clean it often , cause it’s tricky and I don’t need to.