History of Blank and Missing Things: Telescope Tubes

JF Ptak Science Books  Post 1127

One of the greatest missing things in the history of astronomy thankfully never came to be.  When the Hubble space telescope was having its very early problems, Senator Barbara Mikulski (D, MD) suggested and pursued the idea for bringing the Hubble down and end the program rather than repair it–for financial reasons, or something, I dunno.  It was an toweringly bad idea that keep itself alive for too long (and was just so bad that NASA I recall had a hard time getting their head around such a bizarre problem-solving approach to a fixable problem)–Mikulski went on to not think about other things, the Hubble was fixed, resulting in a simply astonishing amount of discoveries and data that could absorb astronomers worldwide for generations. (In another part of the wanting-to-make-things-disappear is House Speaker Dennis Hastert, who wondered why exactly in the days after Katrina if we should rebuild New Orleans.  But that’s another story.)  Hubble is still there; so is Mikulski, who now is the champion of “the people’s telescope” and who chairs the committee responsible for NASA’s funding. 

One of the most powerful blank/missing or empty things in the history of astronomy that did come about may very well be Christiaan Huygen’s telescope¹ without a telescope tube. Presented to the Royal Society in 1691, Huygens instrument (also known as an “aerial telescope”) was meant to perform the world’s most powerful optical observational instrument, having a focal length of 122'.  Monster telescopes were not practical at that time given the weight and flexure and movement of what would be a massive multi-hundred-foot-long telescope tube.  And so Huygens came up with the idea of doing away with the cumbersome part of the large telescope.

Huygens was a very smart man, and one of very few people acknowledged in Newton’s Principia (along with “Dr. Hollis” and Christopher Wren, the three referred to as “the greatest geometers of our time”)), a man who Newton found to be “the most elegant of any mathematical writer of modern time”. He was extraordinarily accomplished, almost so as much as the half-forgotten Robert Hooke...Huygens was by far Hooke’s superior in mathematics, but Hooke was probably more accomplished across a wider variety of fields, which is saying mounds because Huygens did about everything..  In any event, Newton found Huygens to be an extraordinary scientist, even though Huygens didn’t really quite ever get Newton’s universal gravitation–a high elevation, perhaps among the highest, coming from the cranky Newton. 


Getting back to the telescope–its missing section was perhaps one of the most important developments in astronomy in the second half of the 17th century.  Its arrangement was very elegant, and simple–the mast held the object glass whose position could be changed with a series of simple pulleys and pulls; the eyepiece was placed on a table, aligned with string and rope.  And that was it.  By the first third of the 18th century, James Bradley was able to construct a telescope of this type with a focal length of 212 feet, and used it to measure the diameter of Venus.

Technology would soon catch up to the Huygens invention, but not really for another 75 years. 

Notes.
See:  “Christian Huygens and the Development of Science in the Seventeenth Century”, by E. N. DA C. ANDRADE, in Nature 162, 472-473 (25 September 1948). 

1. Astroscopia Compendiaria tubi optici molimine liberata (compound telescopes without a tube), published 1684.

Comments

[Jeff Donlan]

Can something be called missing if it's not needed?

[John F. Ptak]

Jeff--yes. Especially if it suits the purposes of my category. Seriously though, I see your point, but sure, things can be not needed and missing--I think today we actually have collection places of the missing unneeded thing: television and stores.