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 2020

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Choose Month and Year:
MonTueWedThuFriSatSun
 
1
Waxing Gibbous Moon
2
Full Moon
3
Waning Gibbous Moon
4
Waning Gibbous Moon
5
Waning Gibbous Moon
6
Waning Gibbous Moon
7
Waning Gibbous Moon
8
Waning Gibbous Moon
9
Waning Gibbous Moon
10
Last Quarter Moon
11
Waning Crescent Moon
12
Waning Crescent Moon
13
Waning Crescent Moon
14
Waning Crescent Moon
15
Waning Crescent Moon
16
Waning Crescent Moon
17
New Moon Crescent Moon
18
Waxing Crescent Moon
19
Waxing Crescent Moon
20
Waxing Crescent Moon
21
Waxing Crescent Moon
22
Waxing Crescent Moon
23
Waxing Crescent Moon
24
First Quarter Moon
25
Waxing Gibbous Moon
26
Waxing Gibbous Moon
27
Waxing Gibbous Moon
28
Waxing Gibbous Moon
29
Waxing Gibbous Moon
30
Waxing 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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