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3D Supernova Simulation! September 27, 2009

Posted by jcconwell in Astronomy, supernova.
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What’s a simulation? It’s a computer model, usually of a complicated system, that can’t be solved using pencil and paper. You tell the computer what the physical laws are, usually in the form of differential equations, and let the computer try to solve them.  They are also used in design and prototypes of airplanes, buildings and complicated systems. Simulations are also used in cases where doing lab measurement might not be possible, think nuclear detonations, and their big brother, type Ia Supernova.

Type Ia supernova are thought to be caused by a white dwarf stealing mass from a companion star. If it exceeds Chandrasakar’s limit of 1.4 Solar Masses, it will start to compress and detonate. They have found a new importance in astronomy as standard candles to measure distance. It is thought that since they detonate at the same mass they will have the same brightness. They’ve been used to measure Hubble’s constant in the distance past and are the foundation for the existence of the accelerated universe and the existence of dark energy.  BUT  it not KNOWN if all behave the same. Maybe small variations of  chemical abundance or rotation change the energy given off by the supernova. That’s were the simulations are important.

3D simulations take a big computer. The computational requirements can go up like the 4th power of the grid size (how finely divided do chop up a linear dimension in the star). So up until this point most simulations have been 2D or 1D. When simulations went from 1D to 2D new physics appeared. Asymmetric explosions and other effects not seen in simpler simulations. It is expected that going to 3D we’ll be able to see new effects. If you are interested in Computational Physics, Eastern has a an option in its physics major. Contact either me ( Dr. Conwell) or Dr. Zou for more information.

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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.

Sunspots at last & Astronomy Club tonight! September 23, 2009

Posted by jcconwell in Astronomy, IYA 2009, Solar and Space weather.
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After many months of a dry season the first major group of sunspots for this solar cycle 24 have appeared around the bend. Now we can try our new solar filter for the 16 ” telescope….if only it would stop raining. To see more live pictures go to SOHO’s web site.

SUNSPOTs from SOHO 9/23/2009

SUNSPOTs from SOHO 9/23/2009

Also telescope training tonight at teh Astronomy club. Room 2153 physical science building at 8:00 PM.

“WHEN STARS ATTACK” September 16, 2009

Posted by jcconwell in IYA 2009, supernova.
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THURSDAY, Sept 17 in the Phipps Lecture Hall at 7:00 P.M

Crab Supernova.

Crab Supernova.

“When Stars Attack! In Search of Near-Earth Supernova Explosions,” a presentation by a University of Illinois faculty member, will continue Eastern Illinois University’s yearlong celebration of the International Year of Astronomy.

Brian Fields, associate professor of astronomy and physics at the U of I, is to speak at 7 p.m. Thursday, Sept. 17, in the EIU Physical Science Building’s Phipps Lecture Hall. The event is free and open to the public.

In a supernova, a massive star is destroyed in an extremely powerful explosion, leaving behind a neutron star or a black hole. A shock wave carries the star’s ashes — newly created heavy elements — through space, stirring interstellar gas and, at times, spurring the formation of new stars. Fields will discuss how recent evidence suggests that radioactive iron atoms found deep in the Earth’s ocean are debris from a star exploding near Earth about 3 million years ago.

In addition to giving scientists a clue of what powers supernovae, the findings suggest that the explosion’s proximity to Earth might have had major results on the planet, Fields wrote. “An explosion so close to Earth was probably a ‘near-miss,’ which emitted intense and possibly harmful radiation,” Fields wrote on his Web site. “The resulting environmental damage may even have led to extinction of species which were the most vulnerable to this radiation.”

Fields’ presentation will be the first event of the fall semester in EIU’s yearlong celebration of the International Year of Astronomy. IYA is a worldwide commemoration of many historic astronomical achievements, including the 400th anniversary of Galileo’s first look through a telescope and the 40th anniversary of man’s first steps on the moon.

EIU’s IYA events are sponsored by the EIU College of Sciences and the EIU Department of Physics.

New Podcast: Planet-Searching at the Gemini Observatory September 9, 2009

Posted by jcconwell in Astronomy.
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Sponsored by the Physics Department of Eastern Illinois University

The Gemini Observatory consists of twin 8-meter optical/infrared telescopes built and operated by a consortium consisting of the United States, United Kingdom, Canada, Chile, Brazil, Argentina, and Australia. Scientists from around the world utilize the twin telescopes to explore the universe from both hemispheres of our planet.

http://365daysofastronomy.org/2009/09/09/september-9th-planet-searching-at-the-gemini-observatory/

365_iya

http://365daysofastronomy.org/2009/09/09/september-9th-planet-searching-at-the-gemini-observatory/

Astronomy Club Tonight! September 9, 2009

Posted by jcconwell in Astronomy.
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Room 2153 in the Physical Science Building at 8:00 PM. We will learn about IYA events and be the first to see the poster for our IYA speaker next week. See what a 42″ wide printer can do!

At the Tarbel Art Center: Art and Archeoastronomy ! September 7, 2009

Posted by jcconwell in Art, Astronomy, IYA 2009.
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M33 Summer Solstice

Summer solstice setting at an Anasazi Ruin (Credit: J Krebhiel)

 

 

We are lucky to be having a return visit from one of our IYA speakers from the spring. Professor Jim Krehbiel, chair of the Department of Fine Arts at Ohio Wesleyan University. This month EIU’s Tarbel Art Center will be showing an exhibit of Jim’s work. The digital art prints by Jim Krehbiel are based on his exploration and photography of the architecture, art and astronomy of the ancestral Pueblo peoples; presented in conjunction with the International Year of Astronomy; funded in part by the College of Arts & Humanities Excellence in Fine Arts Visiting Artist Fund. The opening artist lecture will be Tuesday, September 8th, at 7:00PM, in the Tarbel Atrium with refreshments.

Mt Wilson time-lapse film looking East September 5, 2009

Posted by jcconwell in Astronomy, Observatory.
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This clip is from Professor Mike Brown professor of planetary science at Caltech. A time lapse view from the Mt Wilson Towercam looking East into the fires from last night. It looks very much like lava flows in Hawaii. The bright object rising near the end of the clip is Venus.

Mt. Wilson back on line and OK ….for now. September 5, 2009

Posted by jcconwell in Astronomy, Observatory.
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The internet connection that was put out by the backfires (lit to burn up fuel around Mt Wilson) was back up on Friday afternoon.

Mt Wilson 9/5/09

Mt Wilson 9/5/09

As a result of the events of the last week, Mt Wilson is  going to be sorely pressed for resources to take care of cleanup and further preparation and mitigation activities. If you are interested in helping out with the process of transitioning back to normal operations, They would welcome your tax-deductible donation in any amount. Donations can be sent to: The Mount Wilson Institute, Fire Recovery Program, P.O. Box 1909, Atlanta, GA 30301-1909.

More news can be had at http://www.mtwilson.edu/fire.php

EIU Observatory on WTHI TV September 3, 2009

Posted by jcconwell in Observatory.
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Vodpod videos no longer available.

more about “WTHI Observatory Clip“, posted with vodpod

Last Thursday we got a nice little television spot on WTHI TV,  Terra Haute , Indiana.

So if you have never been to the observatory just look at this little mini tour with Bob Gacki (president of the Astronomy Club) and myself.