What is the nature of the astrological phenomenon expected at the start of the week?
Daniel Dubois (secretary of the Alnitak astro-club): “This is what we call a conjunction or an alignment. This means that objects – planets, stars or others – will find themselves aligned next to each other. What is exceptional in the present case is that this conjunction will concern seven planets (Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune) of which five will be visible simultaneously to the naked eye (Mercury, Venus, Mars , Jupiter and Saturn)”.
How does this happen?
“All these planets revolve around the Sun. On Earth, it takes us 365 days to complete this rotation. But, there are planets that are faster and others that are slower. The closer they are to the Sun, the faster they circle it. In short, the planets rotate in their orbit, while the Sun also moves. Everything is in motion. Then, after a while, these planets find themselves visible from our point of view as if they had arranged to meet in our field of vision. If we know that Halley’s Comet passes every 76 years, I think that such an alignment is even rarer (once every 150 years according to NASA, Editor’s note).”
When will we be able to see this alignment?
“It should be observable over several days at the start of the week. Probably Monday January 20 and Tuesday January 21, and maybe even Wednesday January 22. Each time from 7:30 p.m., 8 p.m. However, an essential condition must be met: that there are no clouds, which is not guaranteed. The rest, we don’t care. Because, generally speaking, observation is easier in winter, with a calmer sky and the absence, for example, of heat haze.”
The club will be mobilized…
“This Monday, January 20, we will be on the Family esplanade from 7:30 p.m. with a telescope and at least one pair of binoculars to help the population observe the phenomenon. If there are no clouds, you are sure to be able to see it. And normally, this Monday, it should be fine.”
-What if I want to try observing from home without the help of the enlightened astronomers in your club?
“The problem is that if you don’t know where to look, you risk spending a little while there! Fortunately, there is a fantastic application, free on computer (paid on mobile): Stellarium. Once our position is entered, it will tell us that of the planets in our sky. Other than that, no need for special equipment. Always provided there are no clouds, it will be possible to observe the phenomenon with the naked eye. Afterwards, with a pair of binoculars, it’s even better.”
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