Monday, March 19, 2012

Vernal equinox 2012

from EarthSky
At 1:14am Eastern Daylight Saving Time, 20 March 2012, spring begins. This date and time mark the vernal equinox- equal hours of daylight and darkness that occur twice a year in spring and fall.

For more information on this in Ball State's University Libraries and online:

Do keyword searches in CardCat for "vernal," "spring," "autumnal," or "fall" "equinox," or "soltices." You can also type in terms such as "astronomy" or "seasons" for more general information.

You can also find books on this subject and astronomy in general on the shelves under call numbers beginning with Q14 (encyclopedia, dictionaries, glossaries, etc.) or QB63-65 (field guides, star charts, manuals, etc.).

More information...
"The Egg and the Equinox" from Phil Plait's Bad Astronomy
Seasons Calculator for Indianapolis IN, years 2000-2049 from
SkyTonight Almanac from Sky & Telescope
"Everything you need to know: Vernal spring equinox 2012." from EarthSky
Earth's Seasons: Equinoxes, Solstices, Perihelion, and Aphelion from the US Naval Observatory