A rare astronomical event is coming next month – on June 3rd, there will be a planetary alignment, and you may actually be able to see six planets align in the sky. So, if you missed the magical display of the northern lights recently, you could get another chance to witness something truly special in the night’s sky in just a few weeks.
We spoke to Kate Pattle, a lecturer at University College London’s Physics & Astronomy Department, to find out a little more about the planetary alignment, and our best chances of seeing Mercury, Mars, Jupiter, Saturn, Uranus and Neptune in the sky together.
What is a planetary alignment?
“A planetary alignment is an astronomical event that happens when, by coincidence, the orbits of several of the planets of the Solar System bring them to roughly the same side of the Sun at the same time,” explains Kate. “This means that they appear in a line on the sky, when we view them from the Earth. In this case, the planets Jupiter, Mercury, Uranus, Mars, Neptune and Saturn will form a line across the sky, in that order.”
Kate points out that, in this instance, ‘planetary alignment’ refers to the planets visibly lining up in the sky – also known as a ‘planetary parade’ – but they won’t be in actual orbital alignment.
“It’s important to emphasise that the planets aren’t forming a straight line in space – that’s a much rarer astronomical event called a syzygy,” she says. “However, because all the planets – including the Earth – orbit around the Sun in roughly the same orientation (moving in which we call the “Plane of the Ecliptic”), when they’re on the same side of the Sun as each other, they appear to form a line in the sky when we view them from Earth.”
Kate also emphasises that although the planets’ orbits have brought them to the same side of the Sun as each other, they aren’t actually close to each in space. “They’re still millions of miles apart,” she adds.
When do the planets align?
The planets are due to line up in the sky in the early morning hours of Monday June 3rd 2024.
How common is a planetary alignment?
Visual planetary alignment, or planetary parade, are quite common, particularly if you’re talking about two, three or even four planets lining up in the sky. However, it’s less common to see five or more planets aligning.
These are the upcoming planetary parades of five or more planets:
- June 3rd 2024
- August 28th 2024
- January 18th 2025
- February 28th 2025
- August 29th 2025
“The February 2025 alignment is a particularly good one,” says Kate, “as all seven of the other planets in our Solar System – Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune – will form a line on the sky (Pluto isn’t a planet, sorry!)”
How to spot the planetary alignment
“Unfortunately, it involves getting up very early in the morning!” says Kate. “The planetary alignment will be most visible about one hour before sunrise on 3rd June, but will also be visible for a couple of days on either side. The planets will be visible in the east of the sky.”
To increase your chances, you need to be in an area with as little light pollution as possible and no obstructions to the horizon, “as Jupiter, Mercury and Uranus will all be low in the sky,” Kate says. “You’ll also need a good pair of binoculars if you want to see all six planets, as Uranus and Neptune are too faint to be visible to the naked eye, and Mercury may also be difficult to spot, as it is quite faint and only rises shortly before the dawn.”
The planets can be difficult to spot in the sky, so try and find yourself a good pair of binoculars (and pray for good weather!)
“Jupiter will be the easiest, as it’s the second brightest thing in the sky after the moon,” Kate adds. “Planets don’t twinkle like stars do, which may help you to identify them. But the best thing to do is to download a night sky app – free options include Sky Map, Star Chart or Sky Tonight, amongst many others – which you can point at the sky to tell you what you’re looking at. Happy planet-hunting!”