Io and Europa cross Jupiter

Io and Europa repeat final week’s transit throughout Jupiter early this morning, with their two shadows within the lead.

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October 10: Spot Ceres in Cetus

Last week, Io and Europa took a visit collectively throughout Jupiter, transiting the planet with their shadows. The moons’ resonant orbits imply comparable occasions usually repeat, and this morning is your likelihood to catch one other one. 

Bright Jupiter stands excessive above the jap horizon through the early-morning predawn hours. By 4:30 A.M. EDT, Europa’s shadow is already seen on Jupiter’s giant disk, whereas Io and Europa sit off to the planet’s east. Note that though it’s Europa’s shadow on the cloud tops, Io seems bodily nearer to the planet, with Europa to Io’s east. Io’s shadow seems at 4:43 A.M. EDT, and by 4:50 A.M. EDT, each are readily seen. 

The two moons proceed approaching Jupiter’s jap limb, with Io reaching it first simply over an hour later, at 5:58 A.M. EDT. The shadows are a bit greater than midway throughout the disk by this level, Europa’s shadow nonetheless main. Europa’s transit begins at 6:43 A.M. EDT, because the shadows are approaching the western limb. The shadow transits finish simply three minutes aside, beginning at 6:53 A.M. EDT. 

If you’ve cloudy skies or just aren’t in a position to catch the transit, don’t fear — there might be one other on the morning of the 18th, though the view might be higher for these within the western half of the U.S.

Sunrise: 7:07 A.M.
Sunset: 6:26 P.M.
Moonrise: 9:38 P.M.
Moonset: 12:50 P.M.
Moon Phase: Waning gibbous (68%)
*Times for dawn, sundown, moonrise, and moonset are given in native time from 40° N 90° W. The Moon’s illumination is given at 10 P.M. native time from the identical location.