An Amazing Model of the 200-inch Telescope

I recently picked up some old Sky & Telescope magazines off of eBay with Palomar Observatory on the cover.

Shown below is the November 1947 issue.

That's not the 200-inch telescope on the cover. It is a model of the telescope - a very impressive model that was built by Clifford E. Raible.

The finished 1/16 scale model was really quite huge. With the model pointed at the zenith it stood nearly six feet high and the telescope's "tube" weighed 95 pounds. The north pier, made of steel, weighed over 300 pounds. It had 12.5-inch primary mirror with a 22.5-inch focal length and a 4-inch secondary mirror. Like the real telescope, all of the mirrors were made of Pyrex glass. The model also contained auxiliary flats mirrors (like our coude flat) that would allow for the light passing through the telescope to be focused at the lower end of the south polar axis, just like the real thing. The model could also have an eyepiece attached midway up the declination arms, making it a working 12.5 inch telescope.

Like the real 200-inch telescope this telescope was motorized and had it's own oil bearings.

Except for a few nuts, bolts & motors, Raible made all of the parts himself, actually casting aluminum parts in his basement on weekends "often working from breakfast to midnight, quitting only at his wife insistence" .

As the parts for the real telescope were being fabricated at Westinghouse, Cliff "was a frequent visitor, spending many hours watching the operation and talking with the workers." This was especially useful for him as he made his own horseshoe bearing for the model.

Here is a photo of the model that ran in the article:

Notice the scaled person in the lower right.

The more I read about this model, the more impressed I got about the amazing work done by Cliff Raible. All of this made me wonder what has happened to the model in the 62 years since the article was published. Does it still exist today? I am not really sure if it does or not.

There were a few clues in the article that sent me scurrying to Google to try to find some answers. Apparently the model was exhibited at the Buhl Planetarium in Pittsburgh and Raible was a member of the Amateur Astronomers Association of Pittsburgh. Thankfully, the AAAP (founded in 1929) is still around and a few of its members had some clues for me.

It seems that 20 or 30 years ago the model telescope was given up by Buhl Planetarium and in the early 90s sold at an auction held at VernonScope. Don Yeier from Vernon Scope confirmed this for me, but I do not know who bought the model or where it resides.

If anyone out there knows of the current whereabouts of the model, please comment or drop me an email to wsk@astro.caltech.edu. I would love to see a modern photo of this. Of course if the current owner does not want it, I am sure that we can find a good home for it here on Palomar.

Thanks to Don Yeier and for the good folks over at Amateur Astronomers Association of Pittsburgh for helping me with some of the pieces on this mystery.

Autumn on Palomar

Here's the view from yesterday morning looking out from next to the 60" telescope out across the valley to the ridge on the other side:

The oak leaves are just now at their peak of color. The color is better this year than it has been in a while because it has been such a mild autumn with no rain or wind events to help get those leaves to drop.

Flight Suit Follow-Up

In a follow-up to yesterday's post of the manual for the F3-A electrically heated flying suit, here is where the astronomers would plug in their flight suits to keep warm:

As you can see there is a nice rheostat so that the astronomer could dial in the correct temperature to counter the cold of the night.

Thanks to Drew from the Palomar Day Crew for providing me with this photo! No one has used them in decades, but the rheostat and outlets are still up in prime focus.

The Return of Flying Electric Trousers

About a year and a half ago I did a post about Flying Electric Trousers, the heated flight suits that astronomers used to wear on cold nights while observing at Prime Focus. The flight suits were surplus F3-A electrically heated flying suits used by the U.S. Army Air Force during World War II.

In addition to having some of the old flight suits hanging around (one is on public display now) we also have one original F3-A manual. The flight suits are a unique piece of astronomical and aviation history. By request, I am posting scans of the entire manual.

The front cover:

Pages 2 & 3:
Pages 4 & 5:
Pages 6 & 7:
The back cover:
The images are posted in full resolution, just click on them to embiggen and read the text.

"Winter" Visiting Hours Return

It is not winter yet, but our "winter" visiting hours resume on Monday, November 2. Until the end of March the observatory will be closing an hour earlier. Our "winter" visiting hours:

From November through March: 9:00 a.m. - 3:00 p.m.

From April through October: 9:00 a.m. - 4:00 p.m.

High Flying Over Palomar

On warm days when the thermals are just right we often see a lot of gliders flying around the observatory. From time to time they pass close enough that you can actually hear them flying.

I guess that is why Pilot Getaways magazine was interested in featuring the observatory in an article on the local community Ramona, CA. That, and the fact that they had this amazing photo of a glider over the observatory:


That is a pretty awesome shot. You'll find it on the cover of the September/October issue of Pilot Getaways magazine.

Just underneath the tail of the glider is the dome of the 48-inch Samuel Oschin Telescope, our one million-gallon water tank, water tower and the Power House. Underneath and to the right of the tail is the Palomar Testbed Interferometer. To the right of that is the dome for the 200-inch Hale Telescope. In front of the Hale is the dome of the 24-inch telescope. Behind and a bit to the right of the Hale is the dome of the 18-inch Schmidt. The observatory's Outreach Center (where I am typing this) is just to the right of the pilots and the Cleveland National Forest's Palomar fire station is to the right of that.

Too Far to Be Seen

Sometimes it is pretty exciting when you look for something and don't see it. Last April there was a gamma-ray burst (GRB 090423) detected by NASA's SWIFT satellite. One of the first ground-based telescopes to look for the visible light afterglow was the automated 60-inch telescope at Palomar. The 60-inch was imaging the source within three minutes of the satellite's detection of the GRB. The result? The 60-inch didn't see it.


You might not expect that I would devote any time or space on this blog for talking about something that we didn't see. But that non-detection (unlike LCROSS) was pretty exciting.

As Brad Cenko said in his report:

The lack of an optical afterglow, together with the fact that the X-ray column density is consistent with the Galactic value (Krimm et al., GCN 9198), make GRB 090423 an interesting candidate high-redshift event. We encourage observations at longer wavelengths to search for a NIR counterpart.

Translation: This object should be bright, but it wasn't seen in visible light. That means it could be an extremely distant event. So distant, that the expansion of the universe shifted its light completely out of the optical and into the infrared. That was indeed the case.

Telescopes observing the object in the near infrared and radio wavelengths did indeed see the optical afterglow of the event and it is the most distant object ever observed.

How far is it? Just over 13 billion light-years from Earth. GRB 090423 occurred 630 million years after the Big Bang, when the universe was only four percent of its present age of 13.7 billion years. Explosions like this give us a glimpse into the early universe and confirm the idea that massive stars, like the one that blew up creating the gamma-ray burst, existed even back then.

Goodbye to Sleuth

From 2003 - 2007 the tiny, robotic 4-inch sleuth telescope spent its nights at Palomar Observatory hunting down exoplanets. The telescope was part of the Trans-Atlantic Exoplanet Survey (TrES), a network of three such telescope dedicated to looking for exoplantes that are seen to directly transit across the face of their parent star.

At the time the survey began, there was just one known transiting exoplanet. TrES added four more exoplanets to the list. Not bad for such little telescopes.

The project was set up by then Caltech postdoc David Charbonneau (now with Harvard) who returned to Palomar earlier this week to to retrieve his little telescope. Even though the telescope had already been out of service for almost two years it was a bittersweet moment. Nobody like to see a telescope retired. The good news is that Dr. Charbonneau is leaving behind a 10-inch telescope ("Sherlock") that was also used for the project. This telescope, which helped to remove false detections from the list of possible exoplanets, will eventually be used for our public outreach programs.

The enclosure that was occupied by Sleuth will be put back into use again. More on that later.

Last Tours of the Season

This weekend (Oct. 31 & Nov. 1) will be the last Hale Telescope public tours of the season. If you have been putting off coming for one of the tours this will be your last chance until they resume in April.

The temperature inside the dome is running about 40 degrees right now and will likely stay in the 40s for the weekend. So if you attend, be sure to bring a warm layer (or two)!

The tours will be held at 11:30 a.m., 1:30 p.m., & 2:30 p.m.

Borego's Dark Sky Day

Last Saturday was the big day in Borrego Springs, CA. A number of people were on hand as it was time for the International Dark-sky Association to officially present Dark-sky Community status to Borrego Springs. Here are a few photos from the event, which was held just outside the Borrego Springs Library.


Bill Horn, a San Diego County Supervisor, spoke about the importance of the dark-skies designation to the community and presented an official proclamation for the event.


Click on the image to embiggen. That way you can actually read the proclamation.


Kim Patten of the International Dark-sky Association spoke on the importance of preserving dark skies and the wonderful skies over Borrego Springs.

Here is the Borrego Springs Dark-skies Coalition as they received the framed certificate from Kim Patten of the IDA. Yes, I am in that shot. I worked with this group for two years to help make this a reality.

Astrophotographer Dennis Mamanna spoke eloquently about the value of seeing the sky from the desert that surrounds Borrego Springs and then presented one of his astrophotos, taken from the area, for display in the town's public library.