Friday, November 20

The Moon reaches apogee, the farthest point from Earth in its orbit, at 12:50 P.M. EST. At that time, our satellite will be 252,040 miles (405,619 kilometers) from Earth.

Already 60° high in the east by 8 P.M. local time is M33, the Pinwheel Galaxy in Triangulum. This lovely spiral glows at 6th magnitude and is technically visible from a dark site with sharp eyes — just wait until after moonset if you want to give it a try. You’ll find it in far western Triangulum, about 4.3° west-northwest of 3rd-magnitude Alpha (α) Trianguli.

Any telescope will show M33, but larger ones are better because its considerable size — some 70’ across along its longer axis — spreads its light out and makes its surface brightness quite low. Instruments 10 inches or larger will show some detail along the spiral arms, including brighter knots of star formation.

Located some 2.7 million light-years away, M33 is the third-largest galaxy in our Local Group, after Andromeda and our own Milky Way.…