Today:
As the Crescent Moon lowers toward the horizon at sundown, it will share the moniker “Heart of the Scorpion” with the star that always holds that title, that star being the reddish giant Antares. Compared to the relatively close proximity of the Moon, Antares shines at a staggering distance of 520 light years, each light year being just short of six trillion miles.
Saturday:
Directly overhead this evening at 7:10 PM is Deneb, the tail of the Swan, or the top of the Northern Cross. Although Deneb appears as the faintest star of the Summer Triangle, it is by far the most powerful. While Vega shines 40 times brighter than our Sun, and Altair about 10 times brighter, Deneb emits an estimated 200 thousand times more light!
Sunday:
Arcturus, the brightest star in the evening skies, still close to due west, appears less than one quarter of the way up as twilight ends, setting earlier each evening, and heads below the west-northwest horizon at 8:00 PM EDT. Arcturus owes its brilliance to its relatively close position, about 37 light years away, while it sends out 170 times more light than our Sun.