Our night sky appears to us like an overarching dome sprinkled with bright points of light. Some of those points of light appear to be very close to each other, and indeed the ancients envisioned the stars as all being the same distance away on that dome. But this is a two dimensional picture, when in fact the universe beyond the Earth’s surface is very much three dimensional.
https://en.wikipedia.org/wiki/Orion_(constellation)#/media/File:Orion_3008_huge.jpg
Take for example the three stars that make up the “belt” in the constellation of Orion. From left to right in the image, they are Alnitak, Alnilam, and Mintaka. Their distances from Earth are respectively, 800, 1340, and 915 light years. The diagram below is a rough representation of how we would see these three stars if we were taken far “above” our current location in the galaxy.
The same is true for much closer objects in our solar system. Take a look at this image—a genuine, not photoshopped photograph.
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The moon is a quarter of a million miles away, while Saturn’s distance ranges from three quarters of a billion to nearly a billion miles—more than a thousand times that of the moon. Clearly, these two objects only appeared to be close on this particular occasion.
On the night of December 21, the winter solstice, Jupiter and Saturn will appear closer to each other than at any other time since 1623—just a few years after Galileo first turned his handmade telescope to the sky. Their separation will be about one-fifth the width of the full moon. It will even be possible to see them together in a single telescopic view.
https://cdn.mos.cms.futurecdn.net/2ArJe7CScK7CeKwwxtWZYo-970-80.jpg.webp
Here is a view from “above” the solar system showing the positions of the planets on that night. From the northern hemisphere, Jupiter and Saturn will be low in the southwest sky just after sunset. Let’s hope for clear skies!
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