Matias Delacroix/AP/File
A telescope can help spot Uranus and Neptune when they appear to be aligned with other planets early Monday morning in most of the world; Sunday is ideal for viewers in North America and Europe.
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A “parade of the planets” is being prepared, during which six planets will appear to line up in the sky before dawn, but only three planets will be visible to the naked eye – and the phenomenon is more common than it sounds.
“You’ll be able to see Mars, Saturn and Jupiter,” said Dr. James O’Donoghue, a planetary astronomer and researcher at the University of Reading in the United Kingdom. “If you have binoculars and know where to look, you could probably see Uranus, but there’s not much point in waiting until near sunrise – you can do it earlier in the night. The bottom line is that you can only see about half of the planets in this planet array with the naked eye.”
The best day to see the spectacle in Europe and North America will be Sunday, about half an hour before sunrise, according to O’Donoghue. Aiming for that time frame would give you a chance to spot Mercury, too, though it might not be easy even with binoculars, he said.
“The problem is that the sun will light up the sky in that area,” O’Donoghue added. “It’s just before sunrise, but it’s still going to be very, very bright in the sky, and you probably don’t want to point your binoculars near the sun either.”
If you have one, a telescope would help, especially if you’re hoping to spot Uranus and Neptune. “But to actually see them, you have to zoom in so much on one target that you can’t see the others anyway, so you’d get rid of your field of view,” he said.
The order in which the planets will line up on Sunday is Jupiter, Mercury, Uranus, Mars, Neptune and Saturn, followed by the crescent moon. Later in the week, by Thursday, the Moon will move out of the way — reducing light pollution, O’Donoghue noted — and Mercury will switch positions with Jupiter.
The alignment will be visible to sky watchers everywhere, but ideally the date to see the planets at their closest alignment may vary depending on where you are in the world.
It is important to note that this alignment does not occur in space, but only in the sky as seen from our planet.
“From the vantage point of someone standing on Earth looking up at the sky, it will look like there is a more or less straight line of planets, what you might call a planetary alignment or a planetary parade,” said Dr Kate Pattle, a lecturer in the Department of Physics and astronomy from the University of London.
“But physically there is no real alignment happening. It’s just that most of the planets are more or less on the same side of the sun at the moment. If the planets actually aligned with each other in space, it would be called a syzygy, which is a much, much rarer event,” she added.
This type of planetary alignment is actually not rare at all. “There will be a few more in the next few years, as the outer planets move in the sky more and more slowly the further away they are from us, creating a lot of chances for alignments like this to happen,” Pattle said. “Actually, a better one will probably happen next February, when we’ll have all the planets in the sky at the same time, including Venus, which is missing from this one.”
Pattle recommends Monday, about an hour before sunrise, as the best time to see the show in most of the world, and she is more optimistic about Mercury joining the group of planets visible without instruments.
“Mercury is usually visible to the naked eye if you’re somewhere with low light pollution, but it’s better with binoculars because (the planet) isn’t particularly bright and is only visible just before dawn, so it’s usually against a fairly bright background,” she said.
An app like Stellarium Mobile or Night Sky can come in handy if you’re not sure where to look, ideally somewhere with low light pollution and a low horizon, as Jupiter, Mercury and Uranus won’t be very far above that, he said. Pattle.
You should also try to be somewhere with a good view to the east, as it will be more or less in the direction of sunrise. “Jupiter will be the easiest to spot, because it will be the brightest thing in the sky after the Moon,” Pattle said. “Other planets are not easy to distinguish, but they don’t twinkle in the same way as stars, so that’s one way to spot them.”