USNO astronomer Dr. William Hartkopf kindly offered to give me a tour of the observatory, and I enthusiastically accepted.
I arrived at the USNO, and parked in front of the main building. The gold time signal ball is recent, installed for ushering in the new millenium, but it has only been used twice.
The old 6 inch transit sits in the foyer of the main building.
Only after Hipparcos had proved itself was the transit retired.
The six inch eyepiece and micrometer.
The six inch transit looking south.
Bill then ushered me into one of the most beautiful rooms I have ever seen. The library is filled with wonderful old books, ancient clocks, and other memorabilia.
Another wide angle view of the library.
Here's Asaph Hall's discovery log of the Martian moons, along with various awards he received for the discovery. You can read the log in the high res version of this photo.
A book of Tycho Brahe's observations published during his lifetime.
Brahe himself wrote and published this one, including the manufacture of the paper it's printed on.
Bill and librarian Sally Bosken describe the details of the Tycho book exhibit.
Next we went upstars to have a look at the 12 inch Clark. Before we entered the dome, I had a glance at the observatory roof. Bill points out it's a great place to watch the July 4 fireworks.
Here's the 12 inch Clark with Bill for scale.
Another view of the 12 inch Clark.
We then left the main dome to walk to the 26" Clark. Here's a parting view of the 12 inch dome from the west.
The 26 inch Clark. The largest refracting telescope in the world, in 1873.
I was wondering how one reached the eyepiece on this telescope. Then Bill pushed a button, and the largest elevator in Washington DC and the surrounding suburbs lifted us towards the telescope. Impressive!
The 26 inch Clark, looking west. The small room just to the south of the telescope is an old photographic darkroom.
Years ago, an assistant was trapped inside the darkroom when the door handle failed. He managed to do considerable cosmetic damage before someone let him out.
Finally, here's the old micrometer, now put out to an honorable retirement, as an exhibit. USNO astronomer Charles Worley made some 40,000 measurements of double stars with this, and it stands ready to work again, in the event of a cataclysmic computer failure. That's an impressive number of measurements. In the past 8 years, I've only made 2332 double star observations, and far fewer accurate measurements!
Another view of the old micrometer. You can see how it looked, mounted on the 26 inch Clark.
The office of a working astronomer.
