May 13
The Trailing Hem
Sun Position
The Sun is in Taurus at about +18.7° declination. Northern spring evenings are mild and long; the Sun sets well to the northwest. In the south, autumn's approach is felt in cooling evenings and earlier sunsets.
Sky Highlight
Virgo is the largest zodiacal constellation and, in May, rides high across the meridian at mid-evening from northern latitudes. Its brightest star Spica serves as a directional anchor, reachable from the Big Dipper by the Arc to Arcturus, Spike to Spica mnemonic, a practical springtime navigation aid.
Deep Sky Object
M49 (NGC 4472), the brightest galaxy in the Virgo Cluster, about 56 million light-years away. An elliptical galaxy with little obvious structure but very high surface brightness, it was actually the first Virgo Cluster member to be catalogued and is bright enough to detect in binoculars from dark sites. Visible from both hemispheres.
Featured Star
Syrma (ι Virginis) is a yellow-white subgiant 69.8 light-years away, spectral class F0IV. Its name comes from the Greek word for a trailing garment, an image the old star catalogs associated with Virgo's southern hem. The name arrived in medieval Europe via Arabic translations of Ptolemy, giving it a combined classical and Islamic astronomy lineage.
Around This Date
- May 13, 1964Maarten Schmidt announced the optical identification of the quasar 3C 273, showing it lay at a redshift of 0.158, placing it far outside the Milky Way and making it among the most luminous objects then known.
- May 11, 1916Einstein presented his completed general theory of relativity, which would later be confirmed through the 1919 observation of light bending around the Sun.
Names travel a long way to settle on a star.