Aptly called “The Harvest Moon,” the first full moon nearest to the autumn equinox earned its name from farmers who would use the early moon rise for harvesting crops. During the course of the year, the moon will appear faster and faster. By the time the autumn equinox comes, the moon has gone from a fifty minute elapse from sunset to a twenty-five minute elapse. Meaning that the timing of the moon’s appearance gives the illusion that the moon is closer to earth. This is known as the “moon illusion.”
Harvest Moons are more common between September 8th and October 7th at least in the northern hemisphere of the world. In the southern, Harvest Moons appear during March and April. What made September 23rd, 2010’s Harvest Moon so special was it appeared on the same night of the autumn equinox. The last time this event occurred was on September 23rd, 1991. Exactly nineteen years ago to the date. Scientist predict the phenomenon will not happen again until 2029.
Three things are characteristic of a Harvest Moon; a signature orange glow, large size, and brightness.
THE GLOW
Not all Harvest Moons are orange. Some are red, the moon reflects color much like the sky. The atmosphere reflects particles back to the viewer and creates a red or orange appearance. Harvest Moons are not so much about the color, but the two Ts… tremendousness and timing.
SIZE- the Tremendousness part.
As stated before the large size of a Harvest Moon is mere illusion. Because the moon appears earlier in autumn, it’s location in the sky makes it appear larger, when it isn’t. “Moon Illusion” refers to the difference of when the moon has just risen and is near the horizon and when the moon is higher in the sky.
BRIGHTNESS- it’s all about the timing.
The brightness of a Harvest Moon is all about timing. Since the sunset and moon rise are so close together, it only appears brighter.
There is a lot of romanticizing of the Harvest Moon. The yearly event is often the back drop for romance movies, horror stories, and sometimes used as a symbol of later life. Much like the season of Autumn itself. It continues to be a star gazer’s delight. Bold and beautiful, the Harvest Moon captures its audience and never lets go. One of the greatest optical illusion you’ll ever see.
Information gleaned from the following sources:
- http://curious.astro.cornell.edu/question.php?number=529
- http://science.nasa.gov/science-news/science-at-nasa/2008/16jun_moonillusion/
- http://www.space.com/spacewatch/super-harvest-moon-earth-seasons-100923.html
- http://science.nasa.gov/science-news/science-at-nasa/2010/22sep_harvestmoon/
- http://www.csmonitor.com/Science/2010/0923/Harvest-moon-on-fall-equinox-won-t-be-seen-again-until-2029
- http://earthsky.org/astronomy-essentials/harvest-moon-2
- http://space.about.com/od/calendarsofevents/a/harvestmoon.htm
- http://www.nj.com/gloucester-county/towns/index.ssf/2010/09/the_strongest_link_shine_on_sh.html
