Wednesday, 24 January 2018

Upside down moon



We had an upside down moon last night. It was also a bright orange colour, which unfortunately does not show in this photograph. It was spectacular.

An upside down moon is a result of the moon's orbit around the earth, and the earth's orbit around the sun. And exactly when you see the moon in the shape of a U (lit on the bottom) rather than a backward C depends on what latitude you are at.

We see the moon in the night sky because it is reflecting light from the sun. So the lit part of the moon always points towards the sun. As the earth travels around the sun, the tilt of the earth on its axis sometimes points the northern hemisphere towards the sun and sometimes points the southern hemisphere towards the sun. But this also changes the apparent path of the moon across the night sky when you are on earth looking out at it.  Sometimes it travels at an angle towards the horizon and sometimes it travels straight down toward the horizon. When the crescent moon travels straight down the horizon, you will get the U shaped moon. This can happen once or twice a year, depending on the latitude of your location.

2 comments:

  1. I saw this today and saw three constellations

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  2. Thx for the info

    ReplyDelete