Need to know exactly what time the sun will set on Sept. 26, 2065? Or when
it rose in 565 BC? How about the length of daylight a week from Tuesday in
Albuquerque, N. M.? Just go to NOAA’s solar calculator, now available on
the Web.

A product of NOAA’s Air Resources Laboratory, in Boulder, Colo, the
sunrise/sunset calculator went on line two years ago, according to John
Augustine, a NOAA meteorologist in Boulder, Colo. The updated version
became available this week.

“We wanted the ability to calculate solar noon in the field,” said Chris
Cornwall, a NOAA/CIRES electrical engineer. “That’s important when you have
instruments that have to be aligned north and south.”

What started out as a purely scientific device has found favor with people
from all walks of life, Augustine and Cornwall said.

“We have photographers who use it to take advantage of the available
daylight,” Cornwall said. “There was also a request from an architect who
was working on solar lighting for a building in Hawaii and needed to know
when and where the sun would be.”

In addition to questions from students, Augustine added that they’ve
received many requests from religious people who need to know the exact
time of sunrise and sunset for the beginning and end of religious holidays.

The original program was developed by Cornwall and Aaron Horiuchi from work
started by Chris Lehman.

Since the calculator has been updated, Augustine and Cornwall estimate that
it’s accurate “from 1,000 BC to 3,000 AD.”

Relevant Web Sites

* NOAA’s solar calculator

* NOAA Research

* NOAA’s Air Resources Laboratory

* NOAA’s Surface Radiation Research Branch