Prepare to witness a celestial event that’s been dubbed the “star of Bethlehem” in our night skies in coming weeks.
Dr Daniel Cunnama, science engagement astronomer at the South African Astronomical Observatory, confirmed that a spectacular conjunction of Jupiter and Saturn on December 21 will be visible in South Africa.
“You can look to the west just after sunset and you will see them over the next two weeks.”
Download a graphic which shows how this happens here
According to the BBC’s Sky at Night magazine, the closest giant planetary “kiss” since 1623 will see gas giant planets Jupiter and Saturn just 0,06° apart.
“Our Solar System’s two gas giant planets have been edging closer in recent months, and on Monday, December 21 Jupiter and Saturn will be less than a degree apart in the night sky,” says the magazine.
The spectacular sight will be visible in clear skies across the world.
Sky at Night said Jupiter and Saturn won’t really be close to each other at all.
“In fact, on that date — which also just happens to be the date of the December solstice — Saturn will be about twice as far from Earth as Jupiter will be.
“However, our line of sight from Earth will suggest otherwise, as we all get to witness (clear skies allowing) the closest planetary conjunction of Jupiter and Saturn that most of us are ever going to see.
“Saturn and Jupiter appear to pass close to each other, as seen from Earth, every 20 years, and when they do we call it a ‘great conjunction’.”
If you see it, count yourself lucky.
The last time Jupiter and Saturn were this close was on July 16, 1623, though that occurred just 13° east of the Sun so it’s almost certain no one saw it, wrote Sky at Night.
The last time a “great conjunction” occurred that was as easy to see as this year’s was on March 4, 1226.
The magazine writes that where and when you observe it from will be critical.
They advise being at a place with a good westward view without trees or buildings blocking the horizon.
“Through binoculars, the observer will easily see Jupiter and Saturn separately in the same field of view.
“Ditto a small telescope, which will only need a low-power eyepiece (around 50x) to separate the two planets in the same field of view.”
They write that it should also be possible to see Saturn’s rings, its giant moon Titan, and Jupiter’s Galilean moons Ganymede, Io, Callisto and Europa all in the same field of view.
A 200 mm lens will be required to capture a photograph of the planets and possibly Jupiter’s moons in the gathering darkness, they advise.
The next great conjunction will happen on March 15, 2080.