Retrogrades
In 2010, Mercury is retrograde 4 times: from December 26, 2009 to January 15, from April 18 to May 11, from August 20 to September 13, from December 10 to December 30. Venus: from October 8 to November 18. Mars: from December 20, 2009 to March 10. London time.
from December 26, 2009 to January 15
Stops and turns back on December 26, 2009 at 14:38, at 21°47' Capricorn
Moves forward again on January 15 at 16:51, at 5°33' Capricorn
Shadow: from December 9, 2009 to February 4; the planet crosses the same degrees three times.
from April 18 to May 11
Stops and turns back on April 18 at 05:06, at 12°37' Taurus
Moves forward again on May 11 at 23:26, at 2°39' Taurus
Shadow: from April 4 to May 28; the planet crosses the same degrees three times.
from August 20 to September 13
Stops and turns back on August 20 at 20:58, at 19°03' Virgo
Moves forward again on September 13 at 00:08, at 5°21' Virgo
Shadow: from August 1 to September 27; the planet crosses the same degrees three times.
from December 10 to December 30
Stops and turns back on December 10 at 12:04, at 5°56' Capricorn
Moves forward again on December 30 at 07:20, at 19°37' Sagittarius
Shadow: from November 22 to January 18, 2011; the planet crosses the same degrees three times.
from October 8 to November 18
Stops and turns back on October 8 at 08:05, at 13°13' Scorpio
Moves forward again on November 18 at 21:17, at 27°39' Libra
Shadow: from September 5 to December 20; the planet crosses the same degrees three times.
from December 20, 2009 to March 10
Stops and turns back on December 20, 2009 at 13:26, at 19°41' Leo
Moves forward again on March 10 at 17:08, at 0°17' Leo
Shadow: from October 17, 2009 to May 17; the planet crosses the same degrees three times.
from July 23 to November 18
Stops and turns back on July 23 at 13:02, at 3°24' Aries
Moves forward again on November 18 at 16:53, at 23°29' Pisces
from January 13 to May 30
Stops and turns back on January 13 at 15:56, at 4°39' Libra
Moves forward again on May 30 at 19:08, at 27°49' Virgo
from July 5 to December 6
Stops and turns back on July 5 at 17:48, at 0°35' Aries
Moves forward again on December 6 at 01:49, at 26°40' Pisces
from May 31 to November 7
Stops and turns back on May 31 at 19:48, at 28°42' Aquarius
Moves forward again on November 7 at 06:03, at 25°54' Aquarius
from April 7 to September 14
Stops and turns back on April 7 at 03:34, at 5°25' Capricorn
Moves forward again on September 14 at 05:35, at 2°47' Capricorn
In 2010, Mercury is retrograde 4 times: from December 26, 2009 to January 15, from April 18 to May 11, from August 20 to September 13, from December 10 to December 30. London time.
Yes: from October 8 to November 18. London time.
Yes: from December 20, 2009 to March 10. London time.
A planet never moves backwards. But Earth and the planet orbit the Sun at different speeds: when one overtakes the other, the planet, seen from here, seems to slow down, stop, back up for a few weeks, then move forward again. It's a perspective effect, regular and predictable centuries in advance.
In astrology, a retrograde planet invites you to go back over what it stands for: for Mercury, the planet of communication, it's a time to reread, review and repair rather than start something new. It's a symbolic reading: nothing proves that Mercury retrograde makes devices break down, but the advice to reread before you hit send always helps.
The shadow, for Mercury, Venus and Mars: the planet covers the same degrees three times, moving forward, backward, then forward again. Some astrologers already see the retrograde's theme in the shadow: a build-up before, a wrap-up after.
A station is the moment the planet seems to stop in the sky, before backing up or moving forward again. We look for it day by day, then refine it to the second with the Swiss Ephemeris (NASA ephemerides); the dates are checked against a second, independent calculation (Skyfield).