August 8
The Dragon's Eye Opens
Sun Position
The Sun is in mid-Leo at approximately +15° declination. Sunset comes noticeably earlier than in June; the Milky Way is well-placed on August nights.
Sky Highlight
The Perseid shower is in its final nights of build-up before the peak around August 12-13. Activity tonight can exceed 50 meteors per hour from northern latitudes under dark skies after midnight, with the radiant high in Perseus.
Deep Sky Object
NGC 6543, the Cat's Eye Nebula in Draco, is a well-known planetary nebula lying roughly 3,300 light-years away with a complex, layered structure visible in larger telescopes. It is circumpolar from much of the Northern Hemisphere and well placed on August nights; it remains low for Southern Hemisphere observers.
Featured Star
Etamin, the K5III orange giant marking the eye of Draco the Dragon, lies 148 light-years away and holds a distinguished place in observational history: in 1725, James Bradley aimed his zenith telescope at it and detected the tiny annual drift of stellar aberration, the first direct evidence that Earth moves around the Sun. Four thousand years earlier, it served as the northern pole star.
Around This Date
- August 12, 1877Asaph Hall discovered Deimos, the smaller and more distant of Mars's two moons, during his systematic search for Martian satellites using the US Naval Observatory's 26-inch refractor.
- August 18, 1877Asaph Hall discovered Phobos, the inner and larger moon of Mars, completing his discovery of both Martian moons in the same observing run just six days after finding Deimos.
Etamin was north star when Egyptians were building the Old Kingdom; by the time Bradley pointed his telescope at it, it had slipped into the dragon's eye, still useful, still watching.