Illustration of astronomical highlights for Aug. 21-22 prepared by Amy Jill Lankey, Buhl Planetarium and Observatory.
By Dan Malerbo Buhl Planetarium and Observatory
Our closest neighbor in space has been moving east, away from the sun, since Friday's new moon, and a thin crescent moon can be seen Tuesday evening at dusk at the bottom of an equilateral triangle formed by Mars, Saturn and Spica.
On Tuesday, look for the 4-day-old waxing crescent moon about one-half degree to the left of Virgo's brightest star Spica, 10 degrees above the west-southwestern horizon at 9 p.m. Mars will sit about 5 degrees above and to the left of Spica, and Saturn will lie about 4 degrees to the right of fainter Mars.
By Wednesday evening, the crescent moon will have passed the celestial triangle and sit about 9 degrees to the right of Mars.
Later this week, when the moon has moved away from the triangle and into the southern sky, you may notice in a darker sky the contrasting colors of the trio of celestial objects that form the triangle. Mars is orange, Saturn is golden, and Spica is slightly blue.