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March 5: Time to observe Comet Wierzchoś
Io transits Jupiter’s broad disk late tonight, beginning at midnight EST.
On the East Coast, Jupiter is still 40° high in the west at local midnight, readily visible as the brightest point of light in Gemini the Twins. Through a telescope, you’ll see the gas giant’s other three moons lined up west of the planet as Io approaches the southeastern limb.
Io’s crossing takes much less time than Ganymede’s a few days ago, thanks to the former’s tighter orbit. An hour later, at 1 A.M. EST (now the 7th for the eastern half of the U.S.), Io has reached the middle of the disk — just minutes after that, Io’s shadow appears at the southeastern limb around 1:05 A.M. EST.
By 2 A.M. EST on the 7th, both Io and its shadow are readily visible together on the disk, as Io approaches the western limb and its shadow is nearly central. Io’s transit ends just under 20 minutes later, with the shadow now roughly in the center of Jupiter’s disk. The shadow takes just over another hour to finish crossing; its exit around 2:25 A.M. CST on the 7th is visible in the western two-thirds of the U.S.
Sunrise: 6:25 A.M.
Sunset: 5:58 P.M.
Moonrise: 9:39 P.M.
Moonset: 7:39 A.M.
Moon Phase: Waning gibbous (86%)
*Times for sunrise, sunset, moonrise, and moonset are given in local time from 40° N 90° W. The Moon’s illumination is given at 10 P.M. local time from the same location.
