Is Mercury retrograde right now?

UmbraLux calculates every date and time on this page itself, with the astronomy library astronomy-engine – the same calculation the UmbraLux app uses for its charts. As usual in astrology, positions are measured in the tropical zodiac: the signs start at the vernal equinox and span 30° each.

Retrograde means: seen from the Earth, Mercury moves backwards through the zodiac for a few weeks. We calculate its apparent longitude and find the moments its motion turns (the stations). The shadow before begins when Mercury first reaches the degree where it will later turn direct; the shadow after ends when it is back at the degree where it turned retrograde.

An automated test compares all stations of 2026 and 2027 with NASA JPL Horizons: within 10 minutes. A station is a very slow turn, which is why sources often give times a few minutes apart for it.

Mercury orbits the Sun faster than the Earth does. When it passes between the Earth and the Sun, we see it move backwards through the zodiac for a few weeks. It never actually changes direction; it is an effect of perspective, like a car you overtake on the motorway. This happens three or four times a year, for about three weeks each time.

In the pre-shadow, Mercury already moves through the degrees it will cross again while retrograde: it begins when Mercury reaches the degree where it will later turn direct. The post-shadow ends when, after the retrograde period, it is back at the degree where it turned. In the astrological tradition these weeks are a time when communication, contracts, technology and travel get extra attention; many use them to review and rework.