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April 8: Bid Winter’s Albireo farewell
Moonless spring evening skies are great for galaxy hunting. Leo is well known for its trio of bright galaxies (M65, M66, and NGC 3628), but the Lion has many more extragalactic targets to offer as well.
One such target is M96, for which the M96 galaxy group — also called the Leo I Group — is named. Glowing at magnitude 9.2, this bright spiral is already some 60° above the southeastern horizon by 9:30 P.M. local daylight time. It’s located near the back feet of the Lion and just east of Regulus, the bright, 1st-magnitude star that serves as both Leo’s “heart” and the base of the Sickle asterism.
Center Regulus in your scope, then slide about 9.4° east to land on M96. The galaxy’s bright center, which is visible even in small telescopes, spans some 6’. Larger telescopes should start to reveal structure in the galaxy’s arms — look especially for a fainter arm that arcs up and away from the core. Large scopes may also show the galaxy’s faint outer ring, as well as the way highly concentrated dust on one side of the galaxy than the other carves a small notch out of the core.
Sunrise: 6:31 A.M.
Sunset: 7:33 P.M.
Moonrise: 2:17 A.M.
Moonset: 11:10 A.M.
Moon Phase: Waning gibbous (51%)
*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.
If you’re up after midnight on the 9th in the Central time zone (early-morning hours of April 10), you can catch the start of another shadow transit this week at Jupiter. The giant planet remains in central Gemini, below the bright stars Castor and Pollux and just 2.5° west of magnitude 3.5 Wasat (Delta Geminorum). It’s easy to point a telescope to the planet, as it’s by far the brightest light in the western sky, much brighter than Castor or Pollux.
Ganymede’s large shadow is crossing from east to west, slowly sliding onto the cloud tops beginning at 12:57 A.M. CDT. The planet is too low (less than 3° high) at this time to view the event from the East Coast, but the western two-thirds of the U.S. can watch as a dark notch starts to form at Jupiter’s southeastern limb, taking roughly 8 to 10 minutes to fully appear. Ganymede itself is just west of the planet; Europa is alone to the east, although as earlier this week, don’t be fooled into thinking this is the source of the shadow. Io and Callisto lie farther west, beyond Ganymede.
Ganymede’s shadow takes more than three hours to cross the giant world; Jupiter will set across the U.S. with the transit underway.
