notation in <http://sd-www.jhuapl.edu/NEAR/ESB/perseus.html>

Mike_Spreitzer.PARC@xerox.com
Wed, 21 Jan 1998 13:21:24 PST

What are the little numbers by the cities?  My first guess was the time (only
the minutes part), but that doesn't work in the examples nearest to my location
(Sacramento, San Francisco).