January 18
The Announcer
Sun Position
The Sun lies in Capricornus, about 20.8° south of the celestial equator. In the Northern Hemisphere the days are still short but lengthening; in the Southern Hemisphere this is high summer with long, warm evenings.
Sky Highlight
Mirzam, just west of Sirius, is a pulsating star so steady to the eye that an entire class of variables is named for it. Best from the Southern Hemisphere.
Deep Sky Object
The Seagull Nebula (IC 2177), a long arc of glowing gas about 3,700 light-years away spanning the Canis Major–Monoceros border. A dark-sky and photographic target, both hemispheres.
Featured Star
Mirzam (β CMa), a blue-white giant in Canis Major, about 500 light-years away. Mirzam, the herald, rising before Sirius to announce the dog star's return.
Around This Date
- January 18, 1977Helios 2, the joint NASA-German spacecraft, reached its closest approach to the Sun at roughly 43.4 million kilometers, closer than Mercury, and a solar distance record that stood until the Parker Solar Probe era.
- January 18, 1778James Cook became the first European to encounter the Hawaiian Islands, which he named the Sandwich Islands, a geographical survey voyage that also conducted stellar observations for navigation.
A star named for arriving just before the brightest of all.