Now we are looking at the Master Clock of the United States, accurate to a billionth of a second per day, with a roomful of computers across the hall to serve as a backup. We can get extremely accurate time by measuring the earth's rotation and breaking it down into fractions of a second. Because the earth is slowing down, every 500 days or so we declare a leap second to make up for the lag.
For those who do not need to consider the earth's rotation to measure time, cesium beams and hydrogen maser clocks, or "atomic" clocks, give us an almost perfect reading.
Chester has loved stars since he was 7 years old and saw Willy Ley's book The Conquest of Space with Chesley Bonestell's great illustrations of the planets.
"For the past ten years," he said, "I've been doing summer stargazing programs for the public out at Sky Meadows State Park near Paris, Virginia, 50 miles from Washington, D.C. That's how far out of town you have to go to see stars."
On the other hand, as instructor Richard Schmidt pointed out, for his Smithsonian Associates classes the city starscape will do well enough for instruction. There is always something to look at, a nearby planet or a constellation. There are star maps to study and slides that show what you can't see if it's cloudy.
Believe it or not, you can have too many stars up there if you're trying to point out the important ones, Schmidt said. A whole skyful of stars can be bewildering.
Bewildering but, as my grandson says, awesome.
By Michael Kernan