Posts by pwsbuilder
“A Deed of More Perilous and Romantic Courage has Perhaps Never Been Undertaken …”
Ormsby MacKnight Mitchel was a tireless scientist and engineer who deserves a share of the credit for shaping American astronomy. He was an institution builder and a self-taught astronomer responsible for starting both the Cincinnati Observatory and our own Dudley Observatory. He was also an inventor, and his chronograph allowed a single astronomer to both make…
Read MoreMaking New Mirrors
This doesn’t look like much, but it was the start of something that was going to revolutionize the field of astronomy. This is a disk of silicon dioxide, also known as silica. Since it is made from very clean quartz sand, it is also known as “fused quartz”. You can think of silica as being…
Read MoreHow to Measure a Mountain Without Leaving Your Observatory
Nineteenth century observatories were more than just places to look at the stars. They were packed with scientific instruments that were useful for all sorts of purposes: highly accurate clocks, barometers, thermometers, transits and other surveying equipment, and so on. Many observatories were staffed by people eager to reach out to the public, either as…
Read MoreInstruments
In regards to the last post, here’s Verplanck Colvin himself, taking notes on the right. The instrument he’s using is called a theodolite, which is essentially a small rotating telescope for measuring horizontal and vertical angles. Well, I guess in this case it’s not really a small telescope at all. That looks like a brass…
Read MoreGoulds all the way back
There’s one advantage to inheriting a library; you don’t just get the books, you also get the bookmarks. This bit of paper was found in one of the books used by Benjamin Gould. On one side are some calculations. On this side is a rough family tree. Like any good Boston pure-blood, Gould was very interested…
Read MoreThe Total Eclipse of 1878
As we gear up for the Eclipse Across America this summer, it’s worth looking back at the history of eclipse viewing and the role it played in modern astronomy. Treks out to some remote location to view a solar eclipse were a type of pilgrimage for American astronomers, bringing together large numbers of scientists in one remote…
Read MoreFrom the Collection: Velocity Model
Image collections can be an entertaining headache. Imagine someone going through the shoebox of old photographs that your parents keep in the closet and trying to figure out each picture. Sometimes the subject of the photo will be obvious. Other times it will be something that no one will ever be able to puzzle out…
Read MoreDr. Boss and the Martians
By now, you’ve probably seen our Outreach Astronomer, Dr. Rapson, talking about the new discovery of exoplanets around the TRAPPIST-1 system. Or maybe you’ve heard her talking about the coming solar eclipse, or the discovery of water on Mars, or any of a number of astronomical topics. She’s fulfilling a role that the representatives from Dudley have…
Read MoreFrom the Library: “A Plan for Securing Observations of the Variable Stars”
Pamphlets were the blog posts of the nineteenth century. They could be quickly and cheaply produced, then distributed either for free or for a few pennies to cover printing costs. If popular, they could be bound and go from being ephemera to being permanent. One fan of the preserving the media, Samuel Johnson, explained the…
Read MoreFrom the Library: Solar Cooker
Here’s another “what is it?” from the image collection: If you’re like me, you associate the phrase “solar cooker” with a summer camp construction project made out of cardboard and aluminum foil, used to toast a marshmallow. But that’s not the limit of solar ovens. At the extreme end of the range, the Odeillo solar furnace…
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