Tags: astronomy


Between Sun And Moon

First off, let me just get this out:

Happy Boreal Autumnal Equinox!
(2309 EDT tonight)

OK, so that said, check this out. This Equinox is occurring very close to (within 370 minutes of, in fact) a full moon. This "Super Harvest Moon" makes the usual harvest moon -- the full moon closest to the fall equinox each year -- extra awesome (and this year includes a nice view of Jupiter later on in the evening). NASA writes (in the article linked above):

The Harvest Moon gets its name from agriculture ... [when] farmers depended on bright moonlight to extend the workday beyond sunset. ... The full Moon closest to the autumnal equinox became "the Harvest Moon," and it was always a welcome sight.

This one would be extra welcome because it is extra "Harvesty."

Usually, the Harvest Moon arrives a few days to weeks before or after the beginning of fall. ... The Harvest Moon of 2010, however, reaches maximum illumination a mere six hours after the equinox. ... There hasn't been a comparable coincidence since Sept 23, 1991, when the difference was about 10 hours, and it won't happen again until the year 2029.

For some cool astronomical viewing, consider the following. Find a fairly open public area near you, like a big field in a park (GoogleMaps is helpful), preferably on higher ground (i used MyTopo's map server for that), and go out there somewhere between the moonrise and the sunset (the USNO's sun/moon data tool is handy for US residents).

True, you can see a full moon opposite the sun around the time of any full moon, but isn't having it be within 5 hours of an equinox that much cooler? :)

(Since the moon isn't technically full until later tonight, one can theoretically see the two together again tomorrow morning, just after sunrise. I may well give it a whirl.)

Happy skygazing, and hope the new season brings you peace and Good Things.