On the night of Monday April 26 to Tuesday April 27, the Moon will be closer to Earth than every other night of the year, making it appear larger than usual.

This phenomenon only occurs once or twice a year. But why do we speak of « super moon »? Will it be really pink? What do you need to know to make the most of it?

Why do we speak of a “super moon”? 

This alignment of the Earth, the Moon and the Sun is an astrological phenomenon which owes its name of « Supermoon » in English (super-moon) to the American astrologer Richard Nolle who named it thus in 1979. Since the term remained, it is notably taken over by NASA.

In fact, the moon will appear larger to us than usual because it will  be closer to the Earth . “The average distance between the Earth and the Moon is 384,000 km,” explains Gilles Dawidowicz, secretary general of the Société astronomique de France. The minimum distance of 356,000 km was reached in 2016, a record since 1948 and which will not happen again until 2034 ”.

The 2016 super moon was 30% brighter than usual. « There, it will be less exceptional but it is still a nice spectacle », warns the specialist. 

With the naked eye, it’s quite difficult to see a difference in size between a full moon and a super moon. If we put two photos side by side, it would be like having a lime on one side and a lemon on the other. Gilles Dawidowicz

Will it be really pink? 

No the moon will not be pink

No need to look for the Moon in the hope of seeing it take on a pinkish hue today: it will not have changed color. The expression « pink moon » has no scientific value.

It is an imprint of a North American cultural tradition, probably stemming from the Amerindians. Moon names were applied each lunar month (not just the full moon day), starting with either a new moon or a full moon. Since the 1930s, these names attributed to the Moon have been used in  The Old Farmer’s Almanac  , an American periodical published since the 18th century, popular for its weather forecasts and cooking recipes. For the month of April, the almanac uses the nickname  « Full Pink Moon »  (which was inspired by the spring flowering of the plant  Phlox subulata ).

NASA regularly uses these nicknames in its official communications, which may contribute to maintaining a certain confusion between this cultural tradition and scientific reality. On April 20, for example, the space agency headlined  “  The Next Full Moon Is A Pink ‘Supermoon’ ,  ” referring to the April 27 Full Moon.

How to observe it well? 

To be full of eyesight, it is better to  watch for the sunset or the sunrise . The Earth’s atmosphere creates a magnifying effect on our vision of the Moon, ideal for taking pretty pictures. 

And for a more precise observation, it is advisable to equip yourself with a telescope or a telescope, « a spectacle without danger », certifies Gilles Dawidowicz.

But for the latter, nothing beats an eclipse for total amazement. Note the date: the next lunar eclipse will take place on November 19, 2021.