'Mercury in retrograde': Should we expect 3 weeks of bad luck?

Mercury is expected to enter retrograde on Nov. 16 through Dec. 6. (REUTERS/NASA)

If you're experiencing a spell of bad luck, many people may ask you the same question: is Mercury in retrograde? Astrologists believe the planet is to blame for bringing periods of misfortune down to Earth – and it's happening again on Friday.

Mercury is expected to enter retrograde, appearing to turn the opposite direction in relation to other planets within its solar system, for the second time in 2018 on Friday. It will remain in that position until Dec. 6.

"Normally, the planets move west-to-east through the stars at night. This is referred to as prograde motion," a blog post by NASA's Astrophysics Science Division (ASD) explains. "However, periodically the motion changes and they move east-to-west through the stars. We call this retrograde motion."

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When planets go through retrograde, they just appear to be moving in the opposite direction when we look up at the sky from Earth.

"It is not REAL in that the planet does not physically start moving backward in its orbit," ASD clarifies. "It just appears to do so because of the relative positions of the planet and Earth and how they are moving around the Sun."

From our point of view, it looks like the planet is making a giant "loop-di-loop or squiggle" in the sky, The Washington Post described in a post last spring.

Since Mercury is the closest planet to the sun, it circles the big star in the center of the solar system faster than any other planet – "every 88 Earth days, traveling through space at nearly 112,000 mph," according to Space.com.

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Therefore, Mercury tends to undergo this effect more frequently than its neighbors, about every four months. And every time it does, astrologers warn people to prepare themselves for weeks' worth of bad first dates, work frustrations and a variety of other problems.

Some believe the idea of the planet turning back represents a suggestion that people should reflect back on their lives. Thus, it's a bad idea to start anything new – relationships, projects, etc. – until Mercury is officially out of retrograde, astrology believers say.

The superstition has grown over the years. Someone even created a website called ismercuryinretrograde.com to track the astrological event and provide an explanation as to why something is "bumming you out."

Astronomers, on the other hand, have repeatedly rejected the theory that Mercury has any impact on your mood or outcome of your day.

"The idea that the gravity from these very distant bodies affects our lives in some way just doesn't work in the framework of physics," Jean-Luc Margot, a planetary astronomer and professor at UCLA, told LiveScience back in 2016.

Columbia University astronomy professor David Helfand agreed, emphasizing that the event is simply an illusion and doesn't have any deeper meaning.

“Magical thinking isn’t going to solve [our problems],” he told the New York Post in 2015. “Astrology has no physical mechanism to explain any physical effect. It doesn’t need to explain anything.”

Many people want to point blame at someone – or something – but whether Mercury is in retrograde or not, you're ultimately responsible for your own actions and life, Helfand added.