Sun and Moon, April 2015


The Sun


The length of daylight grows nearly 90 minutes during April.  By month’s end, the sun is in the sky for almost 14 hours in the Chicago area.  Now rising north of east and setting north of west, the sun’s daily arc across the sky grows longer each day with about 3 minutes added each day.  The blue area on the chart above shows the daylight during the month compared to the bell-shaped curve that indicates the length of daylight for the entire year.

The Moon

NASA Photo
Phase Date/Time Moonrise Moonset
Full Moon 04/04/15 (7:06 a.m.) 6:46 p.m. (04/03) 6:34 a.m.
Last Quarter 04/12/15 (10:44 p.m.) 2:11 a.m. 12:35 p.m.
New Moon 04/18/15 (11:57 a.m.) 6:07 a.m. 7:42 p.m.
First Quarter 04/25/15 (6:55 p.m.) 11:54 a.m. 2:05 a.m. (04/26)
Times are Central Daylight Time for Chicago, Illinois, from US Naval Observatory calculations. (For mjb)

Lunar Eclipse

Photo:  National Geographic

On the morning of April 4, there is a lunar eclipse, part of which is visible from the Chicago area.  The moon sets before the full eclipse occurs.  Here are the events of April 4 for Chicago:

  • April 3, 2015:  The moon rises at 6:46 p.m. CDT
  • During the night as the earth rotates the moon rises higher in the sky and then begins to descend in the west.
  • April 4, 2015:  At 4;01 .m. CDT, the moon begins to move into the outer layer of the shadow.  The moon starts its “penumbral” eclipse phase.  For most observers, they cannot see much darkening.
  • April 4, 2015:  5:15 a.m.  The moon is now low in the west, less than two hours from setting, and the best part of the eclipse begins.  As the eclipse proceeds, the moon moves into the earth’s shadow and begins to darken, and the sky begins to darken because of the approaching sunrise.  Approximately 50% of the moon is immersed in the shadow and eclipsed as the sky brightens and the moon descends toward the horizon.
  • April 4, 2015:  6:58 a.m. CDT.  The moon sets as seen from the Chicago area.

For locations farther west, more eclipse is seen.  Observers California, Oregon and Washington can see the entire eclipse.

The Griffith Observatory’s (Los Angeles) link to a life stream of the eclipse beginning at 4 a.m. CDT:

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