Blue moon? Friday's celestial event comes with a catch
This Saturday, Jan. 30, 2010 file photo shows the full moon from Nairobi, Kenya; as the second one of the month, it is also called a "blue moon." A blue moon is expected to appear at 6:43 a.m. EDT Friday, July 31, 2015. (AP Photo/Sayyid Azim)
This is an astronomy story that comes up only once in a blue moon, like on Friday. Maybe.
When the full moon appears at 6:43 a.m. EDT Friday, it will become the second full moon of July. Geoff Chester of the U.S. Naval Observatory said the traditional definition of a blue moon is two full moons in a month.
It happens about every 2½ years and has nothing to do with color.
But there's a catch that may disqualify this as a blue moon.
Chester said an older definition from a Maine almanac calls a blue moon the fourth full moon in an astronomical season. This is only the second full moon of summer, so by that definition no blue moon.
Light from the setting sun reflects off the One World Trade Center tower as the moon rises in its waxing stage seen from The Heights neighborhood of Jersey City, N.J., Wednesday, July 29, 2015. The moon will reach its full stage Friday in a phenomenon known as the blue moon. (AP Photo/Julio Cortez)
Citation:
Blue moon? Friday's celestial event comes with a catch (2015, July 30)
retrieved 12 December 2019
from https://phys.org/news/2015-07-blue-moon-friday-celestial-event.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.
Your feedback will go directly to Science X editors.
E-mail the story
Blue moon? Friday's celestial event comes with a catch
Your Privacy
This site uses cookies to assist with navigation, analyse your use of our services, and provide content from third parties.
By using our site, you acknowledge that you have read and understand our Privacy Policy
and Terms of Use.
User comments