As the National Air and Space Museum gears up for its All Night at the Museum 40th anniversary celebration July 1-2, I can’t help but recall the night in July 1976 that I almost spent at the newly opened Museum — until the police found me and returned me to my parents, that is.

For more than four decades, the Smithsonian’s National Air and Space Museum has celebrated the greatest achievements in aviation and space history.

I’m snatching moments to write this from Chile, sitting on the floor of the airport, or bouncing up winding mountain roads in a van. I’m here as an Astronomy in Chile Educator Ambassador, with eight other ambassadors.

In our exhibition Time and Navigation visitors can set their watches by a working cesium frequency standard, commonly known as an “atomic clock,” on loan from the National Museum of American History. The exhibit allows visitors to see different methods of measuring time, including mechanical and electrical clocks. A digital display on the atomic clock shows the global reference known as the Coordinated Universal Time or UTC. A separate display connected to the clock shows local time, which visitors can use to set their watches. While the device is not connected to outside time sources, it will keep accurate time within a tiny fraction of a second over the foreseeable future. We jokingly called it our “Box of Time.”

Visitors to our Innovations in Flight Family Day and Outdoor Aviation Display at the Steven F. Udvar-Hazy Center on June 18, are in for a real treat. In addition to the wide variety of aircraft that will fly in for the event and the other special programs planned, Andrew Richardson, the owner of Adams Balloons LLC of Albuquerque, New Mexico, will be making tethered flights with a new Smithsonian hot air balloon, weather permitting. Realizing that we have a beautiful example of a classic Adams wicker balloon basket on display at the Udvar-Hazy Center, Richardson asked if we would accept a modern hot air balloon envelope sporting the Smithsonian logo and colors into the collection. While the Museum has a world-class collection of balloon baskets and gondolas, we did not, in fact, have an envelope. Anxious to fill that gap, we quickly accepted Richardson’s generous offer.

How do you keep time? We use an atomic clock in our exhibition Time and Navigation that is accurate to the tiniest fraction of a second and will remain so for the foreseeable future. Except, of course, when we need to account for a leap second—a second added to the clock to account for Earth’s slowing rotation. Curious how we added that second or how an atomic clock works? Find out in our newest blog post. 

In our exhibition Time and Navigation visitors can set their watches by a working cesium frequency standard, commonly known as an “atomic clock,” on loan from the National Museum of American History. The exhibit allows visitors to see different methods of measuring time, including mechanical and electrical clocks.