Let's quickly recall a few facts: the Moon, the Earth's natural satellite, revolves around the planet in approximately one month, while the latter completes its revolution around the Sun in one year. When these three stars are aligned, we then witness an eclipse, explains astrophysicist Robert Lamontagne.
“In the case of a solar eclipse, the Earth, the Moon and the Sun are aligned” in this precise order, explains the man who has long been director of the telescope at the Mont-Mégantic Observatory. “So the Moon is exactly between us and the Sun. It’s a bit like when we walk outside and it’s sunny: we see our shadow [on the ground]. In this case, it is the shadow of the Moon which happens to touch the Earth. »
The dimensions of the Moon and the Sun as well as their respective distance from the Earth mean that the two stars appear to be approximately the same size in the sky. During a total eclipse, the Moon perfectly covers the Sun, completely hiding it from view for a period of time. That of April 8 will last approximately three minutes.
We can sometimes witness an annular solar eclipse, where the Moon takes up less space in the sky and reveals a ring of light around it as it passes in front of the Sun. The next eclipse visible from Quebec will take place in 2048.
The opposite phenomenon, that is to say when the Earth is aligned between the Sun and the Moon, gives rise to a lunar eclipse (the next one will take place in March 2025 in Canada). The portion of the Moon hidden by the Earth then takes on a reddish tint, the result of solar rays refracted by the Earth's atmosphere. Given the larger size of planet Earth compared to its natural satellite, it is much more common to observe lunar eclipses than solar eclipses, underlines Mr. Lamontagne.
(to be continued)
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