A page from the "Calendars" exhibit...

A month of moons

With this interactive moon phase calendar, you can choose a month and year and see why lunar months aren’t an exact match with calendar months.

September 2015

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Choose Month and Year:
MonTueWedThuFriSatSun
 
1
Waning Gibbous Moon
2
Waning Gibbous Moon
3
Waning Gibbous Moon
4
Waning Gibbous Moon
5
Last Quarter Moon
6
Waning Crescent Moon
7
Waning Crescent Moon
8
Waning Crescent Moon
9
Waning Crescent Moon
10
Waning Crescent Moon
11
Waning Crescent Moon
12
Waning Crescent Moon
13
New Moon Crescent Moon
14
Waxing Crescent Moon
15
Waxing Crescent Moon
16
Waxing Crescent Moon
17
Waxing Crescent Moon
18
Waxing Crescent Moon
19
Waxing Crescent Moon
20
Waxing Crescent Moon
21
First Quarter Moon
22
Waxing Gibbous Moon
23
Waxing Gibbous Moon
24
Waxing Gibbous Moon
25
Waxing Gibbous Moon
26
Waxing Gibbous Moon
27
Waxing Gibbous Moon
28
Full Moon
29
Waning Gibbous Moon
30
Waning Gibbous Moon
    
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For millennia, calendars were constructed according to the phases of the moon. We can only imagine what ancient astronomers thought as they scanned the night sky and saw the constantly changing appearance of this large celestial body.

Step outside! Keep track of the moon in your night sky, and chart the changes yourself. See our tips on how to chart the moon in the sky and explore the phases of the moon over the course of its 29.53-day cycle. In the process, you’ll discover why lunar months aren’t an exact match with calendar months.

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