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What Does It Even Mean that Mercury is in Retrograde?

If you need a sort of flimsy excuse for not replying to text messages, emails, or why your rent is late, for the next week the solar system is your scapegoat.
March 27, 2012, 5:36pm
Image: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

If you need a sort of flimsy excuse for not replying to text messages, emails, or why your rent is late, for the next week the solar system is your scapegoat. No, Sun's current period of solar flares isn't knocking out communications like some feared it might. But for people more astrological than astronomical, gaffes in communication can be attributed to the closest planet to the Sun, Mercury, being in a period of retrograde.

From March 12 until April 4, Mercury will appear to be moving—night by night—from east to west in the Earth's sky, rather than the typical planetary direction of west to east.

According to fans of the Zodiac, when Mercury is in retrograde the best-laid new plans are bungled, mail is lost and miscommunications run amok. Since this article was written under the retrograde Mercury, there's a good chance it won't make sense at all.

From a purely visual (and non-metaphysical) perspective, retrograde motion is tricky to explain (see?) since it involves how you see a moving object from a moving object (both of which are moving elliptically around a third, also-moving object, seen against a background of stars that is also moving. (I guess they are moving, relative to each other, but the distances are large enough that we don't really notice in our brief little life spans. Anyway, the mind boggles).

The easiest analogy is that of passing cars, albeit with literally astronomical distances involved. Imagine zooming past another car on the road, going in your direction; follow it with your eyes, and it seems to move backward in relation to a distant background. The Earth rotates around the Sun much faster than Mars and Jupiter, and so even as we're all going the same direction around the Sun, the outer planets will seem to move backwards. Given the great distances, far out planets like Jupiter show retrogradation for months at a time.

The red line shows where we see Mars against the firmament of the night's stars from here on Earth. The wandering nature of planets was an integral clue in figuring out that the Sun, not the Earth, was the center of the solar system

Mercury and Venus, which are closer to the Sun, do the same thing, however they appear to move backwards as they come 'round the bend and pass us. Due to speed and proximity, Mercury's thrice-annual retrograde is a fast and frequent occurrence relative to the other planets, which may explain why it's such a popular scapegoat in astrology.

Both Venus and Mercury move as shown from Earth's perspective, appearing to slow and move backwards as they revolve around the Sun faster than the Earth does.

The clearest explanation of retrograde revolution that I could find on Youtube comes from the Indian astrologer Umang Taneja. He explains Mercury's motion from the perspective of Earth using Zodiac constellations as reference points.

As an astrologer, Taneja also interprets how this impacts our lives, but he saves that for his books rather than this free video, so it's totes SFS (safe for skeptics). It's akin to explaining how grease spots you missed while cleaning your George Foreman might result in the shape of the Virgin Mary being burned into your grilled cheese, without passing judgment on whether this was the hand of God or simply shoddy washing. (The debate as to whether divine intervention impaired your sponge then follows as a different conversation all together.) There are a few red herrings when you talk about Mercury. Some people attribute retrograde motion to Mercury's unusually elliptical (and rather off-center) orbit and the resulting changing speed of the planet's revolution. Don't listen to them. Mercury is always going around the Sun way faster than the Earth, and all the other planets.

According to NASA

, the Messenger space probe we sent had to speed up 65,000 miles per hour to catch up with the smallest planet. Due to this speed and proximity, Mercury's years are only 88 Earth days long.

In August 2007, Mars appeared to slow and then go backwards before speeding up and resuming on its way in April 2008. Mercury, because it only peeks into our sky near sunrise and sundown is comparatively difficult to photograph.

The next time you need to extricate yourself from a bad date, insist on multiplying your date's age by 4.15 in order to determine how old he or she is, "in Mercury Years!" That should get you some alone time. If your date sticks around, multiply that number by 1.6 and explain that's how many "Mercury days" old they are. You could say that Mercury's year is only 58 Mercury days long, "isn't that neat?" and so on. If that doesn't do the trick, it sounds like someone is quite taken with you and you need to have a serious talk. At that point, simply say "Mercury is in retrograde," and it's simply a bad time to be making plans, and you need to get back to your Tarot cards and astrolabe.

Image credits:
Retrograde Motion in the Copernican System courtesy of Astronomy 161 and the Department of Physics & Astronomy at the University of Tennessee.
Retrograde Venus courtesy of Science U (scienceu.com)
Retrograde Mars (Photograph ©2007–08 Tunç Tezel.)