LASCO coronagraphs have begun providing images of retrograde Mercury.

Mercury's retrograde motion against the background of stars is currently being directly observed in images coming from the LASCO coronagraphs, which study the space around the Sun. Currently, this is almost the only way to observe this unusual motion of this celestial body. The object is currently inaccessible to observations from Earth, as well as to conventional space telescopes, due to its proximity to the Sun.

The planet's retrograde motion began on November 9th. Mercury entered LASCO's field of view yesterday, the 17th, and will remain observable for another six days, until Sunday, during which time it will have traveled the entire distance from the left to the right edge of the telescope's field of view.

Although the retrograde motion of celestial bodies is often associated with astrology and is sometimes even considered a figment of horoscope compilers, it is an objective astronomical phenomenon that once drove more than one medieval astronomer crazy, as it essentially has no explanation in a system where Earth is at the center of the universe. After heliocentric models of the universe were adopted, the phenomenon received a natural explanation, although it did not lose its alluring mystery.

To observe retrograde motion, it is enough to compare the planet's "flight" in photographs with the movement of the surrounding starry sky. Retrograde motion is detected by the clearly visible fact that the celestial body overtakes the stars. This contrasts particularly well with the Sun, which is clearly lagging behind the starry sky, located in these same photographs.

Retrograde motion will end on November 29, after which the planet will return to its normal motion across the celestial sphere.