May 22
The Peculiar Brightest
Sun Position
The Sun is in Gemini at about +20.5° declination. Northern summer is approaching fast. Southern mid-latitudes are past their autumnal equinox and heading toward the June solstice minimum.
Sky Highlight
Late May is the deepest month for galaxy observing from the Northern Hemisphere before the summer Milky Way begins to crowd the evening sky. The Virgo-Coma region is still well up at nightfall, the Leo Triplet is crossing the meridian, and Centaurus A is rising for equatorial and southern viewers.
Deep Sky Object
M63 (NGC 5055), the Sunflower Galaxy in Canes Venatici, about 27 million light-years away. Its many tightly wound arms give it a distinctive texture, and its relatively high surface brightness makes it accessible in smaller instruments. It is part of the M51 group of galaxies. Best from northern and equatorial latitudes.
Featured Star
Alioth (ε Ursae Majoris) is a chemically peculiar A-type main-sequence star 81 light-years away, spectral class A0pCr. It is the brightest star in Ursa Major and the brightest chemically peculiar star in the sky, meaning its spectrum shows abnormal abundances of certain elements, in this case chromium and other rare metals, due to magnetic concentration of those elements in its outer layers.
Around This Date
- May 22, 1969Apollo 10's lunar module performed a low-altitude descent rehearsal over the Moon's surface, coming within 15.6 kilometers of the landing site.
- May 24, 1962Scott Carpenter orbited Earth three times aboard Aurora 7; a control system error led to a longer-than-planned reentry burn and a splashdown 400 km off target.
Magnetism floating iron to the surface of a star: chemistry made visible at stellar scales.