After spending the morning and early afternoon at Fort Davis, we drove out to McDonald Observatory. You can see two of the larger observatories on Mount Locke ahead of us. The Hobby-Eberly telescope is on Mount Fowlkes just to the right of the photo.
Driving up the 6,791-foot mountan is half the fun! More twisty roads with impressive views. We stopped first at the Visitor Center where the girls ran around the courtyard and posed with the sundial. 
We walked the kids through the gift shop while Dad checked out the next available tour time. Then we all drove up higher up Mount Locke to the cluster of observatories on top. In addition to two or three smaller telescopes, the two main observatories are the 1938 Otto Struve telescope with an 82-inch mirror and the 1968 Harlan J. Smith telescope with a 107-inch mirror. At the time each was built, they were the 2nd largest and 3rd largest in the world respectively. Now the Hobby-Eberly telescope is the 3rd largest in the world, specializing in spectroscopy (breaking down light into its component wavelengths.)
Driving up the 6,791-foot mountan is half the fun! More twisty roads with impressive views. We stopped first at the Visitor Center where the girls ran around the courtyard and posed with the sundial. We walked the kids through the gift shop while Dad checked out the next available tour time. Then we all drove up higher up Mount Locke to the cluster of observatories on top. In addition to two or three smaller telescopes, the two main observatories are the 1938 Otto Struve telescope with an 82-inch mirror and the 1968 Harlan J. Smith telescope with a 107-inch mirror. At the time each was built, they were the 2nd largest and 3rd largest in the world respectively. Now the Hobby-Eberly telescope is the 3rd largest in the world, specializing in spectroscopy (breaking down light into its component wavelengths.)Before going into the Smith telescope building, we took in the view from Mount Locke. Below in the valley is one of ten Very Long Baseline Array (VLBA) radio telescopes used to collect extremely faint radio signals from objects in space. (It's a tiny white dot in the upper left portion of the photo, down in the valley.)
Just as viewing telescopes need to be as high as possible in an area of very little light pollution, the VLBA has to be down in the bowl of a valley to avoid picking up stray radio signals from all around.
Our tour actually began outside, on the very windy, cold, side of Mount Locke. (Where he explained about the VLBA and the current observatories.)
Inside the observatory we walked up three or four flights of stairs and gathered in the telescope room. Definitely impressive, the whole room is telescope and computers. I had trouble getting a good photo, so you can't really see the scale of the object. 
The telescope tube is 32 feet long and 12 feet wide. It weighs 160 tons. When most people think of telescopes they think of looking through an eyepiece. This particular telescope isn't necessarily measuring objects seen by the naked eyes.
The end where you might find an eyepiece hooks up to a computer. There are three additional openings that can feed the data straight into one or two specific data collection rooms below.
Our guide rotated the dome ceiling and opened the door in the dome and raised the wind screen. Many factors go into housing these large telescopes, including keeping the inner room approximately the same temperature as the outside during evening hours (so it was pretty cool in there...)
There's even a population of employees that live at McDonald Observatory on Mount Locke, primarily engineers and mechanics tasked with keeping the grounds and telescopes in perfect working order. They have a guest dormitory for UT researchers.
I hope you can read this plaque.
If you know me, you know I work in the UHCL Archives with the Johnson Space Center History Collection. When the guide started talking about lunar laser ranging - basically pinging lasers off of three reflectors left on the moon by Apollo astronauts starting with Apollo 11 - I was thrilled. As a result of this laser ranging, scientists were able to successfully calculate the distance between the Earth and the Moon within... centimeters.
After our tour, headed back into Fort Davis where we stopped at this big green Caboose for ice cream.
Yep, this real-life, formerly working, Burlington Northern was brought to Fort Davis to become the town's first Blue-Bell Ice Cream shop in 2004.
See that "wall" in the center left? Kind of behind Ashley? That's the original "2nd story" Conductor's Chair mounted in the cupola. 
Pretty cool, right!
After ice cream, the rest of the family drove back to Indian Lodge. Completely on a whim, Bryan and I stopped with our girls at the Rattlers and Reptiles museum. No kidding, this is supposedly the largest live rattlesnake museum in the world with over 100 snakes, spiders and scorpions.
It didn't look like much on the outside--especially with a car repair shop on the side--and inside wasn't the Smithsonian, if you know what I mean, but it was very interesting! It's one thing to read about the many various kinds of rattlesnakes in the world, but it's quite another to go from one case to another to see them - alive - big, small (some were tiny) from all over the world!
About six weeks ago I remembered what kind these were, but now I've forgotten. (I should always write down everything when it happens.)
Brenna wanted me to take a photo of the Gila Monster.
After our very busy day (remember this started with a 14 mile hike for Bryan) we picked up pizza for everyone at Murphy's Pizza, which wasn't bad... I especially liked looking at the Ellis Island registration forms mounted on the wall. We have a couple of those in our family as well.
So this concludes Thursday. Friday we headed to Sonora, but I'll tell that tale another night.
