Planets race tonight and year

Jupiter and Saturn visibility has travelled across the southern sky over the year, westward from south-east to middle now: that’s because they’re on the ‘outside lane’ and we’re overtaking on the inside. In contrast to our year (365 days; time measurement created by humanity of course) orbit it takes Jupiter 11.86 years to orbit the sun, and Saturn 29.50, so they are not always seen close together like that; Jupiter will ‘race’ ahead of Saturn.

They also look like they’re travelling westwards each night, but that’s because of our planetary spin. In contrast, Venus is on our inside, taking only 224 ‘days’ to orbit the sun, so is racing ahead, looking as if it’s travelling eastward on our horizon over the year.

It was Galileo’s observations of the full planetary phases of Venus in 1610 that determined planets orbit the sun, rather than Earth.

Venus still looks as if it’s travelling west through the night though, because that’s defined by our planetary spin. As Jupiter lags behind us we see it earlier as our planet twists around anti-clockwise:

Jupiter 12.49 (November 5th) to 11.07 (December 5th)
As Venus races ahead, we see it later:
Venus 3.54 (November 5th) to 5.32 (December 5th)

Eventually, Venus will go out of sight behind the sun, reappearing in our evening as it catches up with us again. This year (2020), space.com writes Venus was in our: Evenings in the western sky at dusk from January 1st to May 24th; mornings in the eastern sky at dawn from June 13 to Dec. 31.

https://www.theplanetstoday.com/
https://www.timeanddate.com

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