Timekeepers!

May 2:
On Monday we drove through a crazy thunderstorm,

including a deluge of HAIL....

to get to the US Naval Observatory in downtown DC.  

The observatory is home to a very large (and somewhat old) telescope which is famous for its role in discovering the moons around Mars.   Because of the aforementioned storm, we didn't actually get to see anything  through the telescope, but we did learn a lot about it.   For instance, it was built in the 1873 and was the largest refractive telescope in the world when it was first built.

Later on the tour guide took us  to the USNO library, which in addition to holding one of the world's most premier collections of books on astronomy and physics, was also a very architecturally beautiful building.

It was difficult to capture the scope of this amazing round room in my camera lens, but suffice it to say, this room ended up one of our favorite parts of the tour. 

The last part of the tour was about what the USNO is most famous for (besides being the site of the home of the Vice President of the United States).....keeping time!  It was fascinating to learn about how time keeping has changed over the years.  As they've moved from tracking the  movements of the earth, to pendulums in vacuums,  and finally to cesium based atomic clocks, time keeping accuracy has gone from 1/10 of a second per day of variation to 1/1000 of a 1/1,000,000,000,000 of a second per day.    

It ended up being a late night, but, heck, since time is apparently  a human invented concept anyway,  we could all sleep more soundly knowing that the timekeeping ability of our clocks are in good hands! 

************************

Random Quotes of the Day: 

"If you have one clock, you think you know what time it is, but can never be sure.  

If you have two clocks, you don't know which one is correct.

So you need at least three clocks, so you can find a mean average time."   

Fact:   The US Naval Observatory has hundreds of atomic clocks.   

"NASA determines how long a second officially is.  USNO determines how many seconds have elapsed.   Therefore NASA is like a stopwatch and USNO is a clock."  

************************