The basics: A retrograde occurs when a planet appears to be moving backwards from our vantage point here on Earth. It isn't actually moving backwards, it just appears that way. Mercury turns retrograde most often, about 3-4 times per year, and lasts for several weeks. When a planet retrogrades, what that planet rules tends to be thrown off, along with what the sign it's retrograding in rules.
With Mercury retrograde, we experience a shadow and a storm. The shadow period starts when Mercury first hits the point in the Zodiac it will turn direct at, and ends when it last hits the point in the Zodiac it will turn retrograde at. Most people don't feel the effects of Mercury retrograde until it enters the storm period though.
The storm period of Mercury retrograde is when Mercury is moving at its slowest, less than 40 minutes per day. Mercury is a fast-moving planet and hates it when he's moving slowly. There's usually two storm periods, one around the time Mercury turns retrograde, and one around when it turns direct.
This Mercury retrograde begins on December 19th at 5:55AM ET and ends on January 8th at 4:43AM ET. The shadow period starts December 1st - January 27th. The first storm period is December 15th - 23rd, and second storm period is January 4th - 12th.
Here we go again! Mercury madness begins on December 19th in earth sign Capricorn, and we can see some issues with governments, politicians, those in positions of authority, traditional establishments, and conventional methods. These things have been under assault anyway thanks to the cardinal t-square we’ve been dealing with, with Jupiter in LIbra opposite Uranus in Aries and both square (hard aspect, three signs away) Pluto in Capricorn. This retrograde has Mercury in the sign of the squared planet, Pluto in Capricorn, so we can see more emphasis on this and less on what we’re missing, which is Cancer: emotional connection, nurturing and support, coming together as one family, having a solid home base and foundation. We can be overly focused on the external with this retrograde, and not have anywhere near enough focus on the internal. It only matters what’s on the outside, not what’s on the inside? Uuuhhhh, no!
This retrograde likely brings about more unsettled feelings with our governments, countries, but we can also see more governments and countries fighting back (not naming names, just pointing at Russia on a map?). More bloodshed in places like Syria? Like there hasn’t been enough! All of this will be especially heightened at the start of the retrograde because Mercury will be conjunct Pluto to kick things off. Lots of intensity, heightened emotions and energy, we’ve gotta channel these productively or we’re going to BLOW!
As an extra note, this retrograde begins at about the same place that the Mercury retrograde we began the year with ended, so whatever the end of that retrograde did for you personally can be brought back up again or come full circle with the start of this retrograde. Just an FYI!
This retrograde doesn’t fully occur in Capricorn though. Mercury moves backward into fire sign Sagittarius on January 4th (9:16AM ET), so the last 4 days of this retrograde are in Sagittarius. It’s not a lot of time spent in this sign, so we get a brief dose of disrupted Sagittarius energy, and can be overly optimistic and stuck in big, unrealistic ideas or focused on braggadocious individuals, have difficulty with travel, institutions of higher learning, or legal issues. Saturn is in Sagittarius, but won’t be conjunct Mercury while he’s in Sagittarius, but we can still feel slightly amplified energy of Saturn in Sagittarius, and feel more restricted and fenced in.
The retrograde does end at a funny point though, conjunct something called the Galactic Center, which is the center of our Universe and is literally a giant black hole. The GC has a lot of power and energy as a result of this, so it’s going to be amplified with the end of this retrograde. How? Don’t know! But where this retrograde ends in your chart, you can see a surge in energy that may require extra effort to manage.
Mercury will make four major aspects while retrograde, the first being a sextile (positive aspect, two signs away) to Neptune in Pisces on December 26th. This can increase compassion, empathy, imagination, and help to make us more sensitive (which we’ll need!). On December 28th, Mercury will conjunct (align with) the Sun and sextile Mars, and this can be a bright spot during the retrograde, helping us to focus on new projects and second chances with the Sun, and giving us the energy and drive to get moving in the right direction with Mars. Finally, Mercury will sextile Venus on January 3rd, and we can be more engaging, have an easier time connecting, and find a softer side. All four aspects are positive, so they help to bring us some pockets of good energy.
There will also be a new moon on December 29th that conjuncts this Mercury retrograde in Capricorn. What kind of hoopla will that create? Perhaps some political chaos and unrest, more raging against governments and the machine, a feeling like we're going backward? Hmm . . .
The retrograde begins at 15 degrees Capricorn, so those of you Capricorns born January 4th - 7th can feel the start of this retrograde most. The retrograde ends at 28 degrees Sagittarius, so those of your Sagittarians born after December 18th can feel the end of the retrograde most.
For the rest of you, check the house(s) Mercury will be retrograding in of your own natal chart, and any aspects Mercury will make during its retrograde to your natal planets, to fully understand how it will impact you personally.
If you have Mercury retrograde in your natal or progressed chart, you may not feel the worst of this. Those individuals generally don't experience the difficulties of the retrograde because it feels more natural to them. Of course, chances are everyone else around them doesn't have the same aspect, so they can still experience difficulties brought on by others.
Suggested Reading: The New & Full Moons page for general interpretations