Dean W. Armstrong

The European Space Agency launched an ambitious set of satellites a few days ago: Herschel is a 3.5m diameter infrared telescope, and Planck...

UPDATE 7/06/2009: Here's the current set of passes. There are another set of convenient evening passes of the International Space Stati...

I've heard this strong station several times now over the past year, usually later at night. It always broadcasts at 5900 kHz (or now t...

You can see the sulfur dioxide (SO2) plume from the Galapagos volcanic eruption via the OMI on the Aura satellite (which I'm using to w...

This such an auspicious year. I watched an interview on Chicago Tonight with one of the creators of "400 Years of the Telescope"...

Joe Cottral managed to get a spare 2.5m satellite dish from western Illinois to Chicago. The rest of the RAS had the responsibility of gett...

This has been sitting in one my browser tabs for a little while and too good not to share. Click to enlarge. Original is 4288x2929.

This is definitely the image of the week for the Redoubt eruption. This is from a Japanese weather satellite staring at the Western Pacific,...

You may recall some fantastic sunsets in Chicago this summer from some eruption in the Aleutians . Now, since Redoubt has erupted, I was cu...

Messier 77, a spiral galaxy in Cetus. Click to enlarge. About 30 minutes exposure. This galaxy is about 50 million light-years away. At t...

An old reflection grating When John Crocker and I built the RAS solar spectroscope ( see some of the spectra here ), we had no budget for th...

It's been posted everywhere, and it doesn't acknowledge the source of the idea as far as I can tell, but here's a fantastic lit...

I took this Wednesday evening. Venus is close to the Earth, big in angular size, close to the Sun and getting lower every day. Turbulence,...

I caught one of the ISS/Shuttle passes on Tuesday evening. All the shakiness of the Shuttle is me and not the Space Shuttle, obviously. You...

Leo 1 is a dwarf galaxy located about 800,000 light years away in the constellation Leo. In fact, you can nearly pinpoint the location of t...