It’s the meeting of the century. This month, Earth’s inhabitants will, with a little luck, be able to embrace the gaze of the solar system’s seven other planets, close to each other so rarely. At least four of them – Venus, Mars, Jupiter and Saturn – as well as the Moon can be admired at the same time with the naked eye in the night sky. A pair of binoculars should be sufficient to complete the picture with Mercury, Uranus and Neptune in the same pocket square.
Bad weather will hardly ruin the party: the show lasts almost two weeks! According to calculations by the Institute of Celestial Mechanics and Ephemeris Calculation (IMCCE), the planets and the Moon will form a line that will be fully visible late at night between 14 and 27 June. The maximum tightening will take place on June 22, still according to this laboratory located in the Paris Observatory. A great gift for the summer: The last time a similar phenomenon occurred was in December 1997, but one has to go back to January 1984 to find a spectacular event, as there are few per millennials. The next opportunity to see this bouquet of planets will take place in November 2124, in 102 years …
If the curious want to see a line, it would be misleading to talk about alignment of planets! This would then mean that they are physically located on the same axis from the Sun to Neptune, which is not the case. But like Earth, these planets orbit the star on the same plane called the ecliptic. This is how they appear from our planet to wander over the weeks over a very narrow strip of sky, in the zodiac signs. In rare cases, the Earth is positioned so that all of its “companions” are located on the same side of the firmament and appear to be in line. The event is rather called “parade of the planets”.
” Be alert “
To observe the entire range of stars between east and south, get ready very early, around 4:30 in the morning, or even 4 in the morning, if you choose one of the last dates of the period. It is important to find a place where the horizon is free, state sine qua non to see Mercury, which will appear shortly before sunrise. “We have to be on the lookout because it does not last for hours. I would say about 15 minutes from when Mercury is high enough to be visible until the end of twilight. We will no longer be in the dark, ”warns Pascal Descamps, head of the astronomical calculation and information department at IMCCE.
Mercury can be a challenge. “It’s always quite difficult to see her. It is the planet closest to the Sun. It is completely bathed in sunlight “, continues Pascal Descamps. ‘It will be impossible to see it with the naked eye. It will be necessary to use optical means such as binoculars or a small telescope. We can find it by where it is: between the Sun and Venus. Conversely, the latter will exhibit a rude sheen, impossible to miss. There will also be no trouble spotting the red Mars on its right side, then the giants Jupiter and Saturn, and why not guess the latter’s rings with binoculars or a telescope.
However, these instruments will primarily be used to locate two small bluish dots. The far left, Uranus, will be embedded between Venus and Mars. As for Neptune, it will be located between Jupiter and Saturn. “This is one of the interests of this approach: using the big bright planets to find the small ones that are not. Uranus and Neptune are not spectacular because they are very far apart, but their appearance is different from a star, “says Pascal Descamps.” We can try to distinguish them with binoculars. The difficulty is always to find a very stable support. Even to observe a shiny body, it is necessary to be wedged in well. It is better to use a telescope on a tripod, “he notes. Depending on whether you choose to observe this large approximation around June 14 or 27, a full moon or a thin crescent moon will appear in the family picture.