<p>With any given star, Jupiter has 3 or 4 triple conjunctions per century, with either 12 or 71 years in between.
These occur with Regulus in 1873, 1885, 1956, 1968, 2039, 2051, 2063, 2134, and 2146.</p>

<p>Jupiter takes 11.9 years to orbit the Sun, advancing at a fairly steady ~30&deg; per year.
From Earth, Jupiter appears to move ~40&deg; forward and ~10&deg; backward in a 13-month cycle.
The <a href="https://en.wikipedia.org/wiki/Apparent_retrograde_motion" rel="nofollow noreferrer">retrograde</a> loop happens when Earth and Jupiter are on the same side of the Sun.</p>

<p>We see a triple conjunction with a star when the retrograde loop encompasses it.
Around the February 2051 <a href="https://en.wikipedia.org/wiki/Opposition_(astronomy)" rel="nofollow noreferrer">opposition</a>, Jupiter has conjunctions with Regulus in October, February, and June:</p>

<p><img src="https://i.sstatic.net/O9z7X.png" alt="Jupiter in Feb 2051"></p>

<p>If Jupiter passes a star while Earth is on the other side of the Sun, we see only a single conjunction, as in August 2003:</p>

<p><img src="https://i.sstatic.net/FLc3w.png" alt="Jupiter and Sun in Aug 2003"></p>

<p>Jupiter-Venus conjunctions occur at intervals of 10 or 14.5 months.
The Jupiter-Venus conjunctions of October 1884 and July 2146 occur reasonably close to a Jupiter-Regulus conjunction in a triplet listed above and far enough from the Sun to observe easily.</p>

CC BY-SA 4.0
2020-05-11T13:50:54.013Z
Thank you so, so much for this detailed answer, Mike. One more question; could you be so kind to tell me out of those triple conjunctions, how many would have happened in the constellation Leo?
Frida
CC BY-SA 4.0
2020-05-11T19:40:28.383Z
@Frida Regulus is in Leo, so...all of them?
Mike G
CC BY-SA 4.0
2020-05-11T20:13:41.140Z
Thank you Mike, and forgive my ignorance in asking what is perhaps a silly question; I just sincerely do not know much about Astronomy. Thank you so much for the time you took to reply to my questions, it is much appreciated! ♥︎
Frida
CC BY-SA 4.0
2020-05-10T05:11:24.450Z
2020-05-10T05:11:24.450Z
Mike G
<p>I am wanting to know if the triple conjunction of Jupiter with Regulus in:
Sep 10, 3 BC
Feb 7, 3 BC &amp;
May 8, 2 BC 
with Jupiter later having a conjunction with Venus in Jun 17, 2 BC has happened since, and if so, how often does this triple conjunction happens? </p>

CC BY-SA 4.0
2020-05-07T21:45:41.003Z
Does this answer your question? [Has the conjunction between Venus, Jupiter, and Regulus only occurred twice in 2,000 years?](https://astronomy.stackexchange.com/questions/11456/has-the-conjunction-between-venus-jupiter-and-regulus-only-occurred-twice-in-2)
James K
CC BY-SA 4.0
2020-05-07T22:01:21.310Z
[Triple](https://en.wikipedia.org/wiki/Triple_conjunction) in the temporal sense, not a dup.
Mike G
<solar-system><exoplanet><jupiter><observable-universe>
How frequently do Jupiter & Regulus have triple conjunctions?
Frida
# How frequently do Jupiter & Regulus have triple conjunctions?

(Asked by: username_0 on 2020-05-07)

I am wanting to know if the triple conjunction of Jupiter with Regulus in:
Sep 10, 3 BC
Feb 7, 3 BC &
May 8, 2 BC
with Jupiter later having a conjunction with Venus in Jun 17, 2 BC has happened since, and if so, how often does this triple conjunction happens?

**Tags:** solar-system, exoplanet, jupiter, observable-universe

> **Comments:**
> **username_1**: Does this answer your question? [Has the conjunction between Venus, Jupiter, and Regulus only occurred twice in 2,000 years?](https://astronomy.stackexchange.com/questions/11456/has-the-conjunction-between-venus-jupiter-and-regulus-only-occurred-twice-in-2)  
> **username_2**: [Triple](https://en.wikipedia.org/wiki/Triple_conjunction) in the temporal sense, not a dup.  

---

## 1 answers

### Answer by username_2 on 2020-05-10. Score: 4 | Accepted answer

With any given star, Jupiter has 3 or 4 triple conjunctions per century, with either 12 or 71 years in between.
These occur with Regulus in 1873, 1885, 1956, 1968, 2039, 2051, 2063, 2134, and 2146.

Jupiter takes 11.9 years to orbit the Sun, advancing at a fairly steady ~30° per year.
From Earth, Jupiter appears to move ~40° forward and ~10° backward in a 13-month cycle.
The [retrograde](https://en.wikipedia.org/wiki/Apparent_retrograde_motion) loop happens when Earth and Jupiter are on the same side of the Sun.

We see a triple conjunction with a star when the retrograde loop encompasses it.
Around the February 2051 [opposition](https://en.wikipedia.org/wiki/Opposition_(astronomy)), Jupiter has conjunctions with Regulus in October, February, and June:

![Jupiter in Feb 2051](https://i.sstatic.net/O9z7X.png)

If Jupiter passes a star while Earth is on the other side of the Sun, we see only a single conjunction, as in August 2003:

![Jupiter and Sun in Aug 2003](https://i.sstatic.net/FLc3w.png)

Jupiter-Venus conjunctions occur at intervals of 10 or 14.5 months.
The Jupiter-Venus conjunctions of October 1884 and July 2146 occur reasonably close to a Jupiter-Regulus conjunction in a triplet listed above and far enough from the Sun to observe easily.

> **Comments:**
> **username_0**: Thank you so, so much for this detailed answer, username_2. One more question; could you be so kind to tell me out of those triple conjunctions, how many would have happened in the constellation Leo?  
> **username_2**: @username_0 Regulus is in Leo, so...all of them?  
> **username_0**: Thank you username_2, and forgive my ignorance in asking what is perhaps a silly question; I just sincerely do not know much about Astronomy. Thank you so much for the time you took to reply to my questions, it is much appreciated! ♥︎  

---

