Sunday, July 02, 2006
NSA and domestic phone spying before 9/11
Bloomberg has the story, and I'm guessing Radio Havana picked it up from there.
That said, I wouldn't trust Radio Havana Propaganda for ANY news, which is why I went looking for proof of the existence of the story as soon as it crossed the airwaves.
Friday, June 30, 2006
The Moon on June 29th
Michael Milligan blogged his viewing of the Moon through the University of Minnesota's 10-inch refractor last evening. A great coincidence (aka clear skies for us both) had me at Ryerson viewing the Moon that evening too. It was a useful starting point to Saturn, Mars, and even the elusive Mercury. I also looked at Jupiter to add to the planet list.
I too photographed it, although I waited until the sun had set, taking the first image at 8:45PM with the intention of getting some of the twilight blue in the image.
This second image is a point-of-view image through the viewfinder.
Earlier I also branded a piece of wood with an "R" for Ryerson using the sun's setting rays.
Thursday, June 29, 2006
The Antennae galaxy from Chicago
I am guessing that the Astronomy Picture of the Day for tomorrow, with the title "cosmic antennae", is likely to be about the Antennae Galaxy, an interacting pair 63 million light-years away in Corvus the Crow, visible now as a compact quadrilateral to the far lower-right of Jupiter blazing in the south after sunset. So, I'm posting a poor image of them now, because otherwise the APOD gets me every time in posting something I should have posted earlier.
I imaged the Antennae (also known as NGC 4038/4039) on April 26th from Ryerson Observatory. The total exposure time was about 85 minutes. My light-polluted skies overwhelmed the faint antennae structure of stars thrown out of the galaxies during the collision. I can see the individual superclusters of bright blue supergiants formed during intense starbirths from the compression of gas clouds during the collison. The two brightest knots in the galaxy (oriented roughly vertical in my image) are actually the cores of the original pre-collision galaxies.
Any variations in the dark gray background are dust donuts from the telescope, and leftovers of a smoothing feature I used to help get rid of the vignetting. My flats were not good enough to use for this processing.
Friday, June 23, 2006
A color illusion
Click here for the illusion:
http://www.lib.uchicago.edu/~dean/blog/illusion.html
The idea is from John Sadowski
I need to find a better horizontal image for this illusion.
Wednesday, June 21, 2006
Pluto's new moons named: Nix and Hydra
Forbes article
Blog post about discovery
Cute:
"The 'P' and the 'L' in Pluto are in honor of the Percival Lowell, who instigated the search that resulted in the discovery of Pluto," Stern told Space.com. "The 'N' and the 'H' are exactly parallel to honor New Horizons which instigated the search that led us to [the new satellites]."
Info from the Southwest Research Institute
Monday, June 19, 2006
A triple junction in the Sky
I called the entry "A Triple Junction in the Sky" because of three distance scales that converge at this place in the sky. Leo I, being a (barely) extragalactic source, is that of all things outside of our own galaxy. It's not the farthest thing in the image; there are many angularly small galaxies that are quite a distance aways. The second scale is stellar: Regulus shines at 75 light-years away. One of the four Royal Stars of Persia, it quarters the sky with Aldebaran, Antares, and Fomalhaut.
The third scale, not visible in the image, is the the planetary scale. Regulus lies nearly on the ecliptic, the plane of the solar system, and the moon frequently occults Regulus. In fact other planetary objects can occult Regulus: the asteroid Rhodope covered it for a few seconds in Europe in 2005. Astronomers can use these occultations to measure the sizes of asteroids.
Be sure to see the large-sized image.
Image copyright: © 2005 Russell Croman, www.rc-astro.com
Wednesday, June 07, 2006
Yerkes Observatory sold
Sure enough, the University has sold Yerkes Observatory to Mirbeau Spa for $8 million. They get most of the land surrounding the observatory for their 72 house development and spa and donate the observatory building and nearby grounds to the city of Williams Bay, which has to agree to this. A non-profit will run the observatory, although the University is paying for the operation for 5 years and the claim is that special taxes of an unknown sort will fund the observatory's mission after that.
Chicago Tribune story archived via U of C News Office.
Official University Press Release
Tuesday, June 06, 2006
Yerkes Observatory News
Friday, June 02, 2006
The Permian-Triassic Extinction: a source?
Ralph von Frese argues that a structure in the crust under Antarctica is a 500km wide impact crater and speculates that is was the source of the Permian-Triassic Extinction event which killed off 90% of all marine species.
Confirmation of this theory would require at least two things: the presence of shocked minerals near the impact crater, and dating of the crater to near the boundary (245 million years ago). It has been assumed by many that if there was an extraterrestial impact that caused the extinction it had hit in an ocean basin, and the evidence on the sea floor had long been subducted (the maximum age of oceanic crust in the Pacific is Jurassic in age).
Some images are here.
EDIT: There is some counter-arguments at Nature. Link via The Esoteric Science Resource Center.
Monday, May 29, 2006
Noctilucent clouds: A volcanic ash cloud from Mt. Pinatubo
I have never seen a noctilucent cloud.
I've been far enough north before, roughly the arctic circle, but I
was up there in September and the clouds are entirely summer events, lit up by sunlight streaming over the pole.
I believe though, that I've seen what they would look like. In late
June of 1991 I was living in Las Vegas with my parents (that's what being in high school will do for you) and was in complete harmony with celestial cycles. Sunrise, sunset, moon phases, etc. There is room for another post in that, but the point I am trying to make was that I was very sensitive to the timing of the sunset and the fading of the daylight.
Mount Pinatubo in the Phillipines blew itself apart in one of the largest eruptions of the 20th century on June 15th. The explosion sent cubic kilometers of material high into the atmosphere, breaking into the stratosphere. Once material is in the stratosphere, the only way of removing it is by gravity or ultraviolet light destruction. Small particles fall really slowly, yah? I didn't think an explosion located literally on the other side of the globe would be so evident.
The sun had just set and I was in my bedroom reading with the fading twilight that was still coming through the windows. After about fifteen minutes, I noticed that instead of getting darker, it had suddenly brightened outside. I went out and was shocked to see a broad glowing cirrus cloud covering the western horizon up to about thirty degrees above the Spring Mountains. The cloud was glowing eerie white-yellow against the deepening blue. I was shocked enough to get my father and showed him
the cloud. It was like a spiderweb of cirrus. The color deepened into fluorescent pink and then faded away nearly an hour after sunset. For a few weeks details in the cloud could still be seen--although it spread and faded away. The nights were not as clear for a year afterward, as the ash slowly fell out of the stratosphere.
The Cocteau Twins "Heaven or Las Vegas" album art reminds me of this period and of the glowing cloud in the west that night.
P.S. This entry was originally written two years ago. I finally found an image I took of it and Venus.
Tuesday, May 23, 2006
Geiger counter for Regenstein back up
89. Find the most radioactive place you can get on campus without breaking any rules, laws, or safety regulations. Record the radioactivity level in μrad/h. [5 points. -100 points if we have to call radiation safety].
Saturday, May 20, 2006
Monday, May 08, 2006
Comet Schwassmann Wachmann 3 passes the Ring Nebula
A fragmenting comet passed the Ring Nebula yesterday:
Animation from Horace Smith
Color image from Stefan Seip / Steffen Brückner.
Spaceweather has many images of the conjunction.
EDIT: This one by Johannes Schedler is great.
SECOND UPDATE: Even Better.
Saturday, May 06, 2006
The old telescope maintenance routine -- a Carl Bamberg transit
One of things we decided to do was to move our Carl Bamberg transit telescope down to the office to decide on cleaning and to see if we can put it out on display somewhere. It's a historical instrument, being the first transit at Yerkes Observatory and on campus here at the University of Chicago for over a hundred years. It's not in use and suffers a harsh life in a box on the roof.
Transit telescopes are meticulously aligned to the meridian (a line running north-south) and are designed to measure the exact moment a known star crosses that line. When that happens, the stellar time is exactly the Right Ascension coordinate of that star. Once you have the stellar (or sidereal) time, it's easy to convert into solar time. This was the premier method of accurate time measurements until atomic clocks appeared. The one we have is called a broken transit because the light is bent 90 degrees in the middle of the instrument. It is also known as a geodetic transit.
Inscribed on the brass objective lens assembly is "Carl Bamberg Friedenau No. 1300."
Also noted, after hearing falcon cries for two days in a row, was I discovered that we are hosting a peregrine falcon's nest just below our office windows. They didn't pick the best of sites: it's in a rain gutter. I wonder if I can get a non-obtrusive webcam pointed at them.
I see the Smithsonian also has a Bamberg transit.
Somebody in Germany has one too (slow link).
Instructions on running University of Washington's transit is here.
And let it be known, any proper Scientific Instrument should be made of brass and green felt.
UPDATE: After looking a NMAH Geodetic Transit, I think the filar micrometer floating around the office could be originally from the transit. Look at the right side of the transit in the image.
Monday, May 01, 2006
Oligarchic Growth of the large planets: from systemic
Wonderously descriptive imagery of the earliest moments of the gas giants by Greg Laughlin at systemic:
The atmosphere bulks up fast. Liberated hydrogen and helium gas bubbles up from the layers of denser materials in the interior. The oligarch passes several Earth masses in size, and grows massive enough to grab gas directly from the disk. Meanwhile, new planetesimals are arriving all the time. Kilometer-sized projectiles streak through the exosphere, exploding as they slam into the atmosphere. The unsettled skies are continuously ablaze with meteors. The temperature rises, becoming so warm that the atmosphere glows a dull coal-red in the darkness of the nebula.
When the growing oligarch, now a full-fledged protoplanet, reaches seven or ten times the mass of the Earth, it is pulling in gas as fast as it can. The atmosphere has swelled and bloated to a thickness of literally hundreds of thousands of kilometers. The gas glows fire-engine orange, and pours infrared light out into space. This radiation is accompanied by slow settling of the lower layers, providing room at the top for more gas to flow in.
Oligarchic Growth