18 Dec 2020

Jupiter and Saturn align in the skies for Christmas

From Afternoons with Jesse Mulligan, 1:30 pm on 18 December 2020

Over the next few days, Jupiter and Saturn will appear to be closer together than they have for 400 years. While they’re technically 730 million kilometres apart, from the Earth’s vantage point they’ll be almost bumping together.

Gisborne astronomer John Drummond is going to be showing the rare event to as many people as he can and joined Jesse Mulligan to explain the phenomenon.

Jupiter and Saturn

Jupiter and Saturn Photo: NASA

“It’s very rare to see two bright planets like Jupiter and Saturn coming close together – it’s called a conjunction.”

He says when it last happened 400 years ago, it happened during the daytime so nobody could have seen it.

While it might be hard to imagine how people throughout human history thought of what they were seeing in past conjunctions, it’s thought that the Christmas star said to be visible when Jesus Christ was born was the alignment of Jupiter and Saturn.

“So it’s quite a good time of year, for this to happen around Christmas.”

Drummond says Jupiter has been quite bright for the last few months as it passes closer to the Earth and it’s typically the most visible planet after Venus.

He says that for the average person without a telescope who wants to observe, the planets will be closest together this coming Monday.

“This will be one of those events where you need to start looking around 8.30pm in the low west near where the sun has set and you’ll see them sitting there in the twilight.”

Monday also happens to the summer solstice, which Drummond says is an intriguing coincidence.

“It’s one of those quirks in nature, and sometimes in astronomy, where everything happens in one day.”

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