Knightridge Observatory

30 05 2011
Knightridge Observatory, Bloomington, Indiana.

Knightridge Observatory, Bloomington, Indiana. Photo credit: JR.

In my earlier post about (then upcoming) events at the New Jersey Astronomical Association, I mentioned that the telescope at the Paul H. Robinson Observatory used a frame and mount acquired from Indiana University in the mid-1960s.  The images of the frame in its previous home on the NJAA website inspired me to make the ten-minute trip over to Knightridge to inspect the abandoned IU observatory.

As you can see from the photo above, the rather squat building is now surrounded by a small, young wood in suburban Bloomington. At the time of its construction in 1936-37, however, this was a relatively remote site. In fact, it’s far enough outside the (then) city limits that I was surprised to see the obvious signs of electrical connections on the outside of the building (below).  My neighborhood, which is closer to town, didn’t get electricity until 1960, so I guess I’m envious that IU managed to run a line out into the fields of Knightridge.

West approach, Knightridge Observatory.

Approach from West, Knightridge Observatory. Photo credit: JR.

The building is in remarkably good condition.  The mortar between the bricks is holding up well, and although the roof is highly oxidized, it’s still keeping the rain water outside where it belongs—for the most part, that is.  The southeast roof of the building, including one of the shutter doors in the dome, was hit by a falling tree, unfortunately. If this hadn’t happened, the interior would still be dry and tight. Now, as you can see, not only are daylight and water making their way inside, so are plant seeds.

Storm Damage, Knightridge Observatory.

Storm Damage, Knightridge Observatory. Photo credit: JR.

From the outside, the dome looks truly round, but the construction details inside tell a different story. Underneath the sheet metal is a dome constructed of jointed wood ribs in-filled with flat lumber that diminished in length as it approached the apex of the dome. It’s not quite a corbeled beehive vault, but it gives a good approximation of the effect, rendered in wood.

Wooden dome, Knightridge Observatory.

Dome Interior, Knightridge Observatory. Photo credit: JR.

The dome was raised on steel tracks that rested on wheels attached directly to the brick walls of the observatory.

Wheel, Knightridge Observatory.

Wheel, Knightridge Observatory. Photo credit: JR.

All of the wires and most of the mechanics that supported the rotating dome have been stripped from the observatory, leaving behind interesting but non-functional bits and pieces on the second story of the building.

Abandoned Knightridge Observatory.

Abandoned Knightridge Observatory. Photo credit: JR.

Because the dome is no longer water tight, this upper floor is starting to rot. The rectangular opening that once held the mount for the telescope frame is dangerous territory, and I can only hope the people who’ve been using the observatory for late night séances are being very, very careful.

Second Floor, Knightridge Observatory.

Second Floor, Knightridge Observatory. Photo credit: JR.

Despite the weather damage, it’s clear that this is one sturdy little building. It’s also clear that Professor Cogshall wasn’t all that concerned about aesthetics.  Reconsider the Lick Observatory: a dome painted to resemble the heavens, walls finished in California redwood, floor finished with a high-polish mahogany. This modest university observatory bears no trace of a finish plaster or floor varnish. Cogshall was here to get the job done, apparently, and saw no need for embellishments that probably wouldn’t look like much under a red light at night, anyway.

You can view a few more photos of the abandoned building on my flickr site.

NRAO Green Bank

27 05 2011
Howard E. Tatel 85-foot Radio Telescope, NRAO, Green Bank, West Virginia

Howard E. Tatel 85-foot Radio Telescope, NRAO, Green Bank, West Virginia

Wednesday’s mail brought me this “vintage” postcard of the Howard E. Tatel Radio Telescope.  Built in 1958, the Tatel was the first major radio telescope at the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia.  Also known as “85-1,” the scope has served as a fixed element in the Green Bank Interferometer (GBI) since 1964.

Back of Postcard, NRAO, Green Bank, West Virginia

Back of Postcard, NRAO, Green Bank, West Virginia

Lick Observatory Historic Photos

26 05 2011

A look at a few of the photos I picked up in California last week:

Great Lick 36" Refractor Telescope

Great Lick 36" Refractor Telescope. Copyright: UC Regents.

Anna Nickel 40" Telescope

Anna Nickel 40" Telescope. Copyright: UC Regents.

Shane 120" Telescope

Shane 120" Telescope. Copyright: UC Regents.

Wallpaper Wednesday

25 05 2011
Alpha Magnetic Spectrometer-2

Alpha Magnetic Spectrometer-2. Photo credit: NASA.

Today’s wallpaper shows the Alpha Magnetic Spectrometer-2 (AMS-02) holding steady in its new home on the integrated truss structure of the International Space Station. Delivered to the ISS on May 19th by STS-134 under the command of Mark Kelly, the AMS-02 will be the first magnetic spectrometer used in space.  From its orbital position, the instrument will gather and measure cosmic rays as part of the on-going search for primordial antimatter and dark matter in the universe.  At the heart of the AMS-02 is a large magnet, the field of which will be used to distinguish matter from anti-matter. As particles and anti-particles pass through a uniform magnetic field, they bend in opposite directions.  The specific particle curvature (positive or negative) identifies the particle as electron or positron.  In addition, the radius of the curvature allows scientists to measure the particles momentum at the time of collection. More on the science (dark matter, anti-matter, strangelets, and cosmic rays) and technology (instruments) of the AMS-02 can be found on the instrument’s website. You can also follow the instrument on twitter @AMS-02.

Lick Observatory

22 05 2011
36" Lick Reflector

36" Lick Refractor. Photo Credit: JR.

Life unexpectedly detoured me through central California last week, so I thought I would take advantage of its (relative) proximity to visit Lick Observatory. The observatory is draped across the uppermost peaks of Mt. Hamilton in the Diablo Range east of San Jose. It’s open to the public on most days of the year, but hours and days are restricted during the winter months, so check the opening schedule before making the drive.

The daytime public program is focused on the historic instruments of the observatory, especially the Great Refractor installed under the dome custom-built for it in 1887.  This 36″ telescope, the lenses for which were ground by Alvan Clark & Son (the same workshop that ground the lenses for the refractors at the Yerkes and Cincinnati observatories), lives in the largest of two domes flanking the Main Building of the observatory.  A 12″ reflector that had been purchased second-hand from Alvan Clark originally lived in the smaller dome at the opposite end of the building; it now houses the 40″ Nickel Reflector. One has to wonder what instrumental astronomy would have looked like in the U.S. at the end of the nineteenth century had Alvan Clark not been around to polish the needed lenses and mirrors.

Interior, Dome at Lick Observatory

Interior of Great Refractor Dome, Lick Observatory. Photo credit: JR.

As you can see from the photo above, the Great Refractor was protected by a dome that was designed with a concern for aesthetics as much as functionality. The underside of the dome was tinted with a color meant to evoke the heavens and the walls were finished with California redwood paneling. James Lick might’ve been an odd guy, but he knew his woodworking.

Observatory floor and gears, Lick Observatory

Observing floor and vertical gear, Lick Observatory. Photo credit: JR.

The floor of the observatory, which was finished with mahogany and ringed with brass railings, was designed to move up and down along a vertical system of spur gears. This cleverness allowed observers to stand on a solid surface while looking through the eyepiece of the telescope, rather than on top of a ladder as was customary with large instruments.

Looking East to Shane 3-meter Reflector, Lick Observatory.

Looking East to Shane 3-meter Reflector, Lick Observatory. Photo credit: JR.

In addition to the guide-led program in the Main Building, there is also a small viewing gallery open to the public in the dome of the Shane 3-meter Reflector. I thought the gallery was under-used, in that the interpretive materials were limited, and public view of the instrument was partially blocked by unidentified objects. The most interesting part of the display was the absolutely ancient black-and-white publicity movie that talked about the early history of the instrument. The corners on Mt. Hamilton Road are so tight that they had to use a relay system to get the 120″ glass for the mirror to its destination, using a crane to transfer the glass from the bed of the truck approaching the corner to the truck waiting on the other side of the corner. You can see below that many of the corners are more than just simple switchbacks, they actually start to double-back on themselves.

Approach to Lick Observatory.

Approach to Lick Observatory, Mt. Hamilton Road. Photo credit: JR.

As an architectural historian, I thought the public program was fascinating; I stood through it twice, in fact. As I was wandering around the larger complex, however, I couldn’t help but wish that public programs spent more time explicating current research and observing practices. I suppose it’s not very practical to demonstrate the Automated Planet Finder or the Katzman Automatic Imaging Telescope; most observational data is crunched with computers manned by tired postdocs. (Take a look at a panoramic view of the control room for the Shane 3-meter during an observing run, for instance. Not enough drama for tourists, I’m pretty sure.) But sometimes I wonder if programs focused on the historical leave the public with the feeling that little has changed in instrumental astronomy in the last century, or if it has, that those changes aren’t important or comprehensible. There are at least ten domes at Lick Observatory and new instruments are being added or adapted on a regular basis. I think if the University of California is depending on public dollars to fund the research at the observatory, it might be good to put more information about current research in visitors’ hands. I enjoyed the slide displays of recent discoveries and accomplishments that lined the halls of the Main Building, but I think it would be more effective to have some of those research goals articulated by the guide during public presentations.

Just a side note: if you’re driving up to Lick Observatory from San Jose, be careful. This is a very popular training route for cyclists (in fact, the Amgen Tour of California passed through the day before I went up), so don’t whip around those blind curves—it’s not nice to run over cyclists with your car.

Wallpaper Wednesday

18 05 2011

Atacama Large Millimeter/submillimeter Array (ALMA) antennae

Atacama Large Millimeter/submillimeter Array (ALMA) antennae. Photo credit: ESO/José Francisco Salgado.

Today’s wallpaper comes to us courtesy of the European Southern Observatory (ESO) in Chile.  What you see are four antennae completed as part of the Atacama Large Millimeter/submillimeter Array (ALMA). ESO and its international partners are in the process of constructing sixty-six of these antennae, all tuned to observe cold-body radiation with wavelengths of a millimeter or less. Radiation with such short wavelengths comes mostly from cold gas and dust clouds, in which stars are being born, or from early, cooling galaxies. Astronomers hope that the information gathered from these cold objects will bring us one step closer to understanding the origins of the universe.

ESO has provided a four-minute “trailer” about the project, available in multiple formats (HD always recommended if your system can handle it) in the video archive. Look for the brief glimpses of the construction equipment.

New Jersey Astronomical Association

16 05 2011

If you’re anywhere near Voorhees State Park in Lebanon Township, New Jersey, make plans to visit the Paul H. Robinson Observatory at 8:30 p.m., May 28, to hear  Robert Zimmerman give a talk, “Unknown Stories From Space: Tales of Space Adventure Few Know About.” The observatory is located about an hour west of NYC, an hour east of Allentown, and an hour north of Trenton—accessible to more people than I can probably count. I’m not sure of Mr. Zimmerman’s exact topic (because the stories are unknown, of course), but if I had to guess, I’d say he was going to be talking a bit about the Hubble Telescope.

The Paul H. Robinson Observatory houses a 16-inch Cassegrain reflector, currently the largest telescope open to the public in New Jersey. I first noticed this instrument when I was doing local history research and discovered the massive mount and frame now in the Paul Robinson observatory was originally installed here in Bloomington at the Knightridge Observatory.  The NJAA website doesn’t mention it, but according to IU history sources, the frame never operated properly.  Even so, the founders of the NJAA paid $100 for the frame and mount (I think we can assume that it would cost considerably more for the system today). If the weather is clear, the telescope will be open to the public after Mr. Zimmerman’s talk. If you do happen to attend, please report back on the state of the frame and mount!

The Astrolabe

14 05 2011


My doctoral research focused on instruments derived from Ptolemaic principles. However, one of the observatories on which I based my project was also associated with an astrolabe foundry during the first half of the 18th century. Technically, astrolabes aren’t Ptolemaic. The stereographic projection on which the astrolabe depends was first described by Hipparchus c. 150 BCE, some 250 years before Ptolemy described it in his Planisphaerium (2nd c. CE). All the same, I could see needing to explain functionality of the instrument to my dissertation committee, so I started keeping track of the better resources on the instrument in my research notes.

A few fragmented astrolabes exist at one of my research sites, mostly in the form of tympani missing the necessary moving parts (the rete, rule and alidade) to make them useful. Staring at the tympani didn’t do me much good and my reading made sense in theory, but lacked practical examples. I really didn’t want to find myself standing in front of my examination committee, stammering for an answer when they asked me to explain how to use an astrolabe to determine local solar time.

Enter Adler Planetarium, the sole purveyor of Roderick S. Webster’s Astrolabe Kit, the solution to my problem.* I’m a great believer in hands-on learning experiences.  If you want to know how something works, try building it for yourself.  Or try putting it back together after you’ve taken it apart. It works with construction methods used in residential design and, as it turns out, it also works with astrolabes.

Front of Astrolabe, showing tympanum, rete and rule

Webster’s kit is a little pricey (around $20) but I think I’ve gotten twenty bucks worth of entertainment and education out of it.  It took me about three days to build the thing because of its complicated glue demands. Without glue, it would’ve required 30 minutes, tops, including sanding the rough edges and assembly. Learning how to use the thing is been a different matter. I’ve spent (literally) hours sitting at my desk working through the various problems it’s supposed to help me solve. Local skies have been persistently overcast, so I’ve been using Stellarium to help me determine the altitudes of various stars (if the skies ever clear up, I’ll be able to sight them through the rule on the back of the astrolabe. IF THE SKIES EVER CLEAR UP.). I’m currently using the tympanum set up for a latitude of 42 degrees.  That gives me the skies about Barcelona (41 23 N), Marseilles (43 20 N), Rome (41 54 N), Sofia (42 40 N), and Vladivostok (43 10 N) with which to play this evening.

Back of Astrolabe, showing rule

And playing is what I’ve been doing. Sidereal time, solar time, time from the sun, sunrise and sunset, the positions of the moon and planets, rising and setting of a few major stars… Some calculations are working better than others, but I’m not quite sure why. Once I’ve determined the latitude of a star and set the rete, I never move it, no matter what problem I’m trying to solve. It’s a bit of a mystery as to why one answer is immediately obvious and the next isn’t, but it’s also a bit of fun.

*N.B. I spent an outrageous amount of time trying to find the kit in the newest version of Adler’s online store, yet still failed to locate it. You might have to call them if you really want one.

Wallpaper Wednesday

11 05 2011

Construction of Mark I Telescope. Photo credit: Jodrell Bank Centre for Astrophysics, University of Manchester.

Today’s wallpaper is a photo taken during the construction of the 76-meter Mark I (Lovell) Telescope at Jodrell Bank.  Designed by Bernard Lovell and completed in 1957, the Mark I was designed for mobility. Lovell had been using a transit telescope, a 66-meter stationary dish pointed at the overhead sky, in his search for cosmic rays.  While the transit instrument was a suitable beginning, Lovell realized fairly quickly that his work was limited by an inability to re-direct the telescope’s attention to other parts of the sky.

The early construction photos are pretty stunning—the photographer(s) did a good job of capturing the complexity of the steelwork needed to support the dish, not to mention the intricacy of the scaffolding used by the construction workers.  Several alterations have been made to the instrument since its completion:  the railroad tracks on which it rotates have been replaced; the support structure has been shored up numerous times; it was given a new reflector in 1970-71 that significantly increased its functionality.  The dish was resurfaced as recently as 2000-2003.

If you’re interested in viewing the Mark I(a)/Lovell telescope in person, check out the Jodrell Bank Discovery Centre online (there is no public access to the research labs at Jodrell Bank Observatory, but you can take a web tour). If you’re curious as to what the Lovell is observing right this moment, you can see a live update on the Jodrell Bank Telescope Status page.  You can even follow the telescope on twitter (@LovellTelescope).

One last note:  if you want to see a truly impressive grant application, read The Blue Book, Lovell’s research and funding proposal submitted to the Department of Scientific and Industrial Research in 1951. Would that everyone could write such a clear explanation of his or her work and its broader impact.

SKA Update

9 05 2011

Good news in the paper this morning:  India gets to join the SKA project, after all!

Observatories and Instruments