February 17

February 17

The Brightest Dog

Sun Position

The Sun is in Aquarius near +7° declination. Northern hemisphere nights are still longer than days; southern summer light fades measurably now.

Sky Highlight

No annual shower today, but Sirius reaches its highest point in the southern sky around 9 pm local time in mid-February for northern observers. February is the peak month for Sirius viewing.

Deep Sky Object

M93, an open cluster about 3,600 light-years away. A compact, arrowhead-shaped open cluster in Puppis with about 80 stars, including several young blue-white giants that give it a bluish cast in long exposures. Better placed for southern hemisphere observers; northern observers near 35°N can still reach it low in winter.

Featured Star

Sirius (α CMa) is the brightest star in the night sky, just 8.6 light-years away, a main-sequence A-type star (A1Vm) roughly twice the Sun's mass, accompanied by a white dwarf companion. Civilizations built temples to its heliacal rising; spacecraft now use it as a navigation reference, its resume spans seven thousand years.

Around This Date

  • February 17, 2001NEAR Shoemaker became the first spacecraft to land on an asteroid, touching down softly on 433 Eros after a year in orbit and returning data for another two weeks from the surface.
  • February 18, 1930Clyde Tombaugh discovered Pluto using a blink comparator to compare photographic plates from January 1930, taken at Lowell Observatory.

8.6 light-years is as close as stars get to us. Sirius is practically a neighbor.