Venus-Saturn conjunction in Sagittarius on Dec 11, 2019 - How often does this happen? Venus and Saturn will be approximately two finger widths apart in the constellation Sagittarius on December 11, 2019. I was wondering: how often do Venus and Saturn come together in the sky like this? I would assume it wouldn't be that frequent. Is it quite frequent? Is there a formula to predict something like this?
To answer How to calculate conjunctions of 2 planets earlier, I computed all planetary conjunctions from -13200 to 17190 and you can search the results at:

http://search.astro.barrycarter.info/index.pl

Prefilled with the values you want (assuming two fingerwidths is 2.5 degrees):

http://search.astro.barrycarter.info/index.pl?p1=Venus&amp;p2=Saturn&amp;lowyear=-13200&amp;highyear=17190&amp;sep=2.5&amp;sunsep=0&amp;submit=SEARCH

and a direct link to the results (with the "LIMIT 200" removed, so you can see all 26,671 results):

http://ae2bcbd33ae927c8e17c62ff155325f3.astro.db.mysql.94y.info/

Note that there are 26,671 2.5 degree conjunctions in 30,390 years, which works out to about 0.88 conjunctions per year.

The http://search.astro.barrycarter.info/index.pl page also provides information on bulk downloading the data, and you may also want to visit:

https://github.com/barrycarter/bcapps/tree/master/ASTRO/CONJUNCTIONS/

Read the README first, but the file you need is the 26.out.bz2 files, since Venus is the second planet and Saturn is the 6th planet.

As always, I'm not perfect, so please don't rely on my results, but do tell me if you find errors, thank you.