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chornedsnorkack
2016-Jan-08, 05:16 PM
Did anyone see it?
I couldnīt. My time was too late in the morning.
No one has a thread about it here. So what was the conjunction like? How big were Venus (small, gibbous) and Saturn (with rings) compared to each other? Compared to their separation (quoted as 5 minutes - how many seconds? From which point to which?)? How did the surface brightness of Saturn and rings compare to dawn sky?
How fast is Venus moving relative to Saturn?

Next conjunction closer than this would be 27th of August, 2016 - but Venus and Jupiter are at elongation of just 22 degrees.
Then 1st of January 2017 - but itīs Mars and Neptune.

Centaur
2016-Jan-09, 12:09 AM
Did anyone see it?
I couldnīt. My time was too late in the morning.
No one has a thread about it here. So what was the conjunction like? How big were Venus (small, gibbous) and Saturn (with rings) compared to each other? Compared to their separation (quoted as 5 minutes - how many seconds? From which point to which?)? How did the surface brightness of Saturn and rings compare to dawn sky?
How fast is Venus moving relative to Saturn?

Next conjunction closer than this would be 27th of August, 2016 - but Venus and Jupiter are at elongation of just 22 degrees.
Then 1st of January 2017 - but itīs Mars and Neptune.

Geocentric minimum separation of 5.1 arcminutes between the planets' centers actually won’t occur until JAN 9 at 04:15 UT (JAN 8 at 22:15 CST). That’s later this evening for those of us in North America, but the pair will not be rising for us until the predawn hours when the separation will have grown wider.

Robert Tulip
2016-Jan-09, 02:48 AM
How fast is Venus moving relative to Saturn?
Venus orbits roughly annually with the sun, while Saturn takes 29 years, so Venus moves in the sky on average 29 times as fast [?] as Saturn. [eta, venus is about φ times as fast as Earth, so its apparent speed relative to Saturn should be about 29x1.62] [eta again, the link below shows Venus starting 2016 at 240° RA and ending the year at 325°, an advance of 85°, but in a period with no retrograde inferior conjunction to earth.

http://cosmoquest.org/forum/attachment.php?attachmentid=21208&d=1451803329 shows Venus in pink and Saturn as a rail track, with their paths in the sky crossing now.

chornedsnorkack
2016-Jan-09, 06:54 AM
Geocentric minimum separation of 5.1 arcminutes between the planets' centers actually won’t occur until JAN 9 at 04:15 UT (JAN 8 at 22:15 CST). That’s later this evening for those of us in North America, but the pair will not be rising for us until the predawn hours when the separation will have grown wider.

If I hadnīt fallen ill yesterday, Iīd have got up early today - and found the weather cloudy.