Airplane of the Day - Boeing E4

KC-46A refueling a Boeing E-4 Advanced Airborne Command Post
at 25,000' MSL over Lone Pine, California on February 19, 2021

The E4's function is to serve as a command post in case of nuclear war. Yes, with a zillion nuclear bombs on hand, nuclear war is still a possibility. Wikipedia has a long article about the E-4. Here's some more pictures.

An E-4B approaching a KC-10 Extender of Travis AFB in preparation for aerial refueling

An E-4 airborne command post on the nuclear  EMP (electromagnetic pulse) simulator for testing

I didn't know there was an EMP simulator, though I should have known. I mean, if nuclear war is a possibility, you want to be prepared, right?

The EMP simulator is at the Kirtland AFB (Air Force Base), Albuquerque, New Mexico. Kirtland AFB uses the same runways as the Albuquerque civilian airport.

National Emergency Airborne Command Post internal configuration, April 1976

We've been playing this game for a long time.

The Night Watch - Rembrandt van Rijn - 1642

The E-4 is the current "Nightwatch" aircraft.  The name "Nightwatch" originates from the richly detailed Rembrandt painting, The Night Watch, that depicts local townsfolk protecting a town; it was selected by the Squadron's first commanding officer.
Wikipedia's digital copy of the painting is available in several different sizes, most of which are suitable for display on a digital display. I don't know what you would do with the largest size, unless you were trying to reproduce the original. It measures 57,813 × 48,438 pixels and requires 274 megabytes of storage space. The original painting is more than 12 feet square, so the resolution works out to about 325 pixels per inch, which is probably good enough to produce a reasonable facsimile. 
Wikipedia's description also names all of the people in the painting:

• Frans Banning Cocq, heer van purmerlant en Ilpendam, 
• Capiteijn Willem van Ruijtenburch van Vlaerdingen, heer van Vlaerdingen, Luijtenant, 
• Jan Visscher Cornelisen Vaendrich, 
• Rombout Kemp Sergeant, 
• Reijnier Engelen Sergeant, 
• Barent Harmansen, 
• Jan Adriaensen Keyser, 
• Elbert Willemsen, 
• Musketier Jan Clasen Leydeckers (behind the Lieutenant in Yellow blowing into the powder pan of a musket which once belonged to Jan Snedeker), 
• Jan Ockersen, 
• Jan Pietersen bronchorst, 
• Harman Iacobsen wormskerck, 
• Jacob Dirksen de Roy (the Governor on far left of the cut off section of the painting), 
• Jan vander heede, 
• Walich Schellingwou, 
• Jan brugman, 
• Claes van Cruysbergen, 
• Paulus Schoonhoven

The order does not seem to have anything to do with the placement of the figures in the painting.