Ring Nebula with the 24″ Telescope

Last night the Introductory Astronomy (ASTR155) class took over the CCD imager on the 24″ telescope.  We checked out a colorful binary star system, Albireo, through different filters and saw the stars change their relative brightnesses as we switched from blue light to red light (one star is redder and the other is bluer, because they are different temperatures).  We also tried some 3-color observing with famous Messier objects, and were able to reconstruct a full-color image of the Ring Nebula.  Here are two pictures from last night’s observing session: the first uses B, V, and R filters to approximate a true-color RGB image of the nebula, and the second uses a narrow-band Halpha filter to bring out the red color and structure of Hydrogen in the outer layers of the nebula (which works great, but with the unfortunate side effect that the background stars look blue!)M57M57Ha

First light for radio telescope!

Beam map made by scanning the radio telescope across the Sun
First light! Beam map made by scanning the radio telescope across the Sun

The students in Wesleyan’s upper-level Radio Astronomy course have spent the semester assembling a Small Radio Telescope (SRT), designed by Alan Rogers at Haystack Observatory. Today the newest member of Wes’s telescopic arsenal saw first light! We employed the total power capability to detect the Sun and used it to map out the telescope beam (spectroscopy is still in the works). Students in Wesleyan astronomy classes can use this telescope to study bright radio sources like the Sun, Cyg-X, and Cas A; map galactic rotation (detect your own dark matter!); and practice principles of radio astronomy.

Many, many thanks are due to the experts who advised the students on assembling the different system components, and worked on some of the hairier machining and electronics: Jon Wallace (Wes alumnus, SARA member, and radio telescope builder extraordinaire), Dave and Bruce Strickland (of the Wesleyan machine shop), and Mike Koziol (our electronics wizard). Wesleyan is the first university to assemble the upgraded SRT system based on the parts list and plans published by Haystack, rather than buying the system as a kit as other universities were able to do in the past, so we needed all the help we could get.  Sophomore Laiya Ackman also volunteered her free time to help assemble the dish.

Everyone gathers around to cut the ribbon!

 

After the ribbon cutting

 

 

 

 

 

 

 

 

You can see photos from the official Wesleyan photo blog here.  And here are a few pictures from various stages of the construction process:

The completed Feed/LNA!  Note that they are standing in a paraboloid shape with the feed at the focus.  Yes, they did that on purpose.
The completed Feed/LNA! Note that they are standing in a paraboloid shape with the feed at the focus. Yes, they did that on purpose.

 

Hoisting the completed dish onto the observatory roof
Hoisting the completed dish onto the observatory roof
Raising the telescope mast upright.  This photo was only sort of staged (just like the actual Iwo Jima photo it is meant to evoke!)
Raising the telescope mast upright. This photo was only sort of staged (just like the famous Iwo Jima photo it is meant to evoke!)

Up On Top of the Volcano, Down in the Submillimeter Valley

Where engineers build their telescopes, astronomers will inevitably come. One of the great perks of having a career path associated with the night sky is the opportunity to visit places where the stars I study shine the brightest. Thanks to Wesleyan University’s newest Assistant Professor of Astronomy, Meredith Hughes, I (Eric Edelman ’13) was able to assist as a student observer at the Submillimeter Array (SMA) on the big island of Hawaii for spring break. Mahalo, Meredith!

The SMA is a telescope array composed of eight individual antennas that specializes in submillimeter, or radio, wavelengths. It is situated near 13,000 feet above sea level, close to the summit of Mauna Kea, one of Hawaii’s inactive volcanoes. This daunting altitude helps the SMA to avoid many atmospheric issues that particularly stymie ground based submillimeter observations. Fortunately, the observing station has an oxygenated control room, so I was able to remain coherent enough during my stay to absorb and document my nights as half guest observer and half gawking, consistently over-impressed tourist.

My five days on the summit gave me a quick glimpse into the many and varied challenges face by ground-based observers. In particular, the weather during my trip was extremely changeable. On my first night at that dark, isolated summit, the starry night sky was clear and vivid enough to drown in. That night, the SMA engineers worked on installing new hardware and the observers set the antennas’ sights on an AGN (active galactic nucleus), which is an extremely luminous galactic nucleus, thought to be caused by large-scale, energetic accretion of matter into the galaxy’s supremely supermassive black hole. However, by my fifth and last observing night, wind and icy snow buffeted the summit, shaded by thick, unmoving clouds, and observing or testing anything was as far from possible as it ever could be. A big portion of an observer’s job is to keep one’s eyes trained on those weather sites in order to adapt accordingly to whatever challenges the fickle weather patterns end up throwing his or her way.

While the sudden snow storm was certainly exciting, I could not enjoy those nights quite as much as I could the clear ones, when actual observing occurred. On those nights, when everything was in working order, every so often I could not help but lean back in my chair in that chilly control room and try and digest the magnitude of this whole operation. Right in front of me, only about ten yards away, was an array of telescopes pointed at and collecting information on an object most likely millions of parsecs away from us. The scale and finesse of observational astronomy has never ceased to impress me, and seeing the SMA in action was a treat to be remembered.

For any readers local to the Wesleyan campus, keep in mind that public observing is held at the campus observatory on clear Wednesday nights from 8:00-9:00pm. We cannot promise you AGNs, but I would still highly recommend a trip to Van Vleck to see the stars if you can make it!