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Browsing Facebook's trending section on the conjunction between Venus and Jupiter, I found several individuals claiming that this is the first time since 2 B.C that the two have gotten as close as they have.

e.g

Chad Tucker claims that "The Star of Bethlehem is shinning (sic) for the first time since June 2 B.C

According to this page, a 'striking' conjunction between Jupiter and Venus happens every 20 years or so, but the definition of 'striking' in this case is one as good as the one in 1916.

So, what I'm asking is, were Venus and Jupiter in a conjunction like the one this year 2017 years ago, and is it the case that we've not had a conjunction like it since?

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  • Part of the excitement (though not in the FB post above) is that the brightish star Regulus is nearby. However, even with that caveat, this isn't the first time in 2017 years.
    – user14703
    Aug 19, 2015 at 14:54

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... were Venus and Jupiter in a conjunction like the one this year 2017 years ago, and is it the case that we've not had a conjunction like it since?

Yes and No, respectively

TLDR: Venus and Jupiter passed in front of one and other in 2 bc and have since done so, but will not do so again until 2065.

Let's get a couple definitions out of the way...

Conjunction

A conjunction is an event when two or more astronomical bodies appear close to one another in the sky.

Occultation

Occasionally they will pass so close to one another that the Moon passes in front of one of the planets; this is called an occultation.

The planets form conjunctions with one another more rarely since they move across the sky more slowly. However, striking planetary alignments typically occur every few years.

As the page you linked : The Frequency of Striking Conjunctions of Venus and Jupiter goes into, the significance is due to how closely they pass. Well, we can do one better, necessarily if they occult, then they must, at some point been the same as this one (and even better). So when was the last Venus-Jupiter Occultation?

Planet-on-Planet Occultations (Worldwide)

Venus-Jupiter: Last 3 Jan 1818 Next: 22 Nov 2065, 14 Sep 2123, 8 Oct 2335, 12 Feb 2912, 8 Nov 2954, 13 Aug 2986

So there was a closer conjunction in 1818.

This page Venus and Jupiter Occultations agrees

1818 3 Jan 21:51 UT 16oW 10",30",12" Occurred over Far East No History Record

but also lists a few going back, including ...

2 BC 17 Jun 17:53 UT 45oW 26",32",28" Very Large Elongation Occurs over Middle East

The next one seems to be in 2065. But it will apparently happen near the sun so won't be possible to see.

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    1) "occulatation" ? 2) Where did the Moon come from in your definition of occultation?
    – DJohnM
    Jul 2, 2015 at 19:29
  • @DJohnM Sorry I hoped it was pretty clear. Conjunction is when two objects appear really closely in the sky. Occultation is when they appear so closely that they overlap. Naturally this happens most frequently when the moon is involved because of its quite large portion of the sky. But planets occult each other as well, but it's extremely rare in comparison. (fixed the typo as well, thanks)
    – Adam Phelps
    Jul 3, 2015 at 1:14
  • According to bogan.ca/astro/occultations/2bcocclt.htm the 2 BC conjunction was a near occultation, not an actual occultation (despite what the another page on the same site says). See also astronomy.stackexchange.com/questions/11456 (9 Sep 1659 was another conjuction, and 21 Aug 2003 was a fairly impressive recent one). You might also google "jupiter venus transit" (no quotes): when a smaller body passes in front of a larger one, it's sometimes called a transit, not an occultation.
    – user14703
    Aug 19, 2015 at 14:58
  • @barrycarter Yeah, there seems to be a slight disagreement on what constitutes an occultation of stars. Possibly due to luminosity? There are certainly degrees of closeness.
    – Adam Phelps
    Aug 20, 2015 at 2:44

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