About every four months people start talking about Mercury in retrograde–the last time being around October. For those keeping track in the year 2020, Mercury was in retrograde from February 17 to March 10, June 18 to July 12, and October 14 to November 3. But don’t worry about missing out, because Mercury is dipping back on January 30 in 2021. Anyway let’s get into it. What’s up with Mercury in retrograde every 4 months?
Apparent Retrograde Motion
First off, yes, this whole deal is an astrology thing. But you don’t have to fret now, since there’s still planetary shenanigans to talk about!
That shenanigans is a phenomenon known as apparent retrograde motion. If you pick apart what the words mean, you’ve probably already figured out what apparent retrograde motion. It just means that planets look like they’re moving the opposite direction compared to every other planet in the system. This is also based on the relative positions of stuff in the system–which is why apparent retrograde motion is only observed sometimes.
By contrast, there’s direct (prograde) motion–which means the planet looks like it’s moving in the same direction as everything else. Both direct and prograde mean the same thing–but the former is considered traditional.
Daily Retrograde Motion
We actually get a chance to see apparent retrograde motion in action once per day. Or rather night. We’re trying to say you get to see apparent retrograde motion all the time with the Moon.
The Moon orbits west to east, though may appear to rise in the northeast (and travel west). Why’s that? Well it’s all due to this little neat thing called supersynchronous orbit. In relation to the Moon, that means the Earth spins once on its axis before the Moon fully rotates around it.
So there you go, it’s not just Mercury. There’s also all the shenanigans around Venus, which is traditionally known to rotate opposite all the other planets. Venus is a bit of a special case, though, and you can read more about Venus and spinning on the blog.
Mercury’s Retrograde Motion
So why does Mercury appear in retrograde every 4 months? Well from our perspective it’s in part because we can’t ever see Mercury in opposition to us. Duh, the Sun’s in the way.
But it’s also because Mercury is in between us and the Sun–so we can see Mercury pass over it. Every planet has a retrograde cycle–it just so happens that Mercury’s is tied to the fact that it’s closer to the Sun than we are.
In the end, it’s because planets orbit the Sun at different speeds. Think about it like a highway. Every now and then one planet “overtakes” the other, just like you passing someone else on the good old interstate. From your perspective, it might look like the other cars are moving backwards.
The Astrology Bit
Briefly, we’ll go over Mercury’s astrological significance, in case you were interested. Retrograde in astrology is normally associated with the planet taking a quick little nap. Also known as whatever benefits the planet is meant to confer are “turned off” for a bit. Mercury is associated with all sorts of messaging and travel–probably because of that God the Romans liked. You know. Mercury. Thus, astrologists very broadly associate Mercury’s apparent retrograde motion with communication breakdowns.
More Mercury trivia here!