Raise your eyes to the sky this week: as of Monday, you will be able to see a “supermoon” in Quebec, which means that it will look bigger and above all brighter. Our natural satellite will be at its perigee, the closest point to Earth.
This phenomenon is due to the fact that the moon does not rotate in a circular orbit, but rather “elliptical”, explains Space for Life on its website.
A full moon occurs at least once a month, but only occasionally, a few times a year, coincides with when it reaches perigee in its orbit, its closest point to Earth. It is therefore at this precise moment that we speak of a “super moon”.
According to NASA, the star then appears 14% larger and 30% brighter. Also known as the “perigean full moon”, this event is an opportunity each year for the curious to photograph the moon with greater clarity, provided of course that the weather conditions are also in the game.
The full moon is expected at 6:39 a.m. on Monday. However, it will only wait for its perigee during the night of Monday to Tuesday. Nuances are also needed in relation to our perception of this spectacle, the human eye being often ill-equipped to assess the size and brightness of the Moon.
“The term supermoon suggests that the lunar disc appears on this occasion much larger than usual. But think again. The Moon’s apparent size, which averages 31 arcminutes, an average distance of 384,400 km, increases to 33 arcminutes at perigee, a distance of 356,700 km. This difference of just over 5% is too subtle to be detected simply with the naked eye. On the other hand, the tides will certainly be more spectacular,” notes Space for Life.
Moreover, several other factors such as light pollution or the presence of mist or clouds can also affect our perception of the supermoon.
If all goes well, this will be the very first “supermoon” of the year 2023. Two more are currently planned for August, and one for September.
In January 2018, a rarer phenomenon occurred when a total lunar eclipse occurred at the time of a second full moon in a month – known as a “blue moon” – even as our satellite natural was closest to Earth.
Result: there was then what astronomers call the “super blue blood moon”. Its next occurrence is predicted in more than ten years, on January 31, 2037.