Judy Isacoff: Ares, Antares, Altair light up sky
Mars, commonly known as the "red planet," named after the Roman god of war, was Ares to the Greeks. Currently, Mars is in the southwest at nightfall, approaching Antares, the red, heart star of the constellation Scorpius the Scorpion. Antares translates to "simulating Mars" (in color) and is widely referred to as "rival of Mars." As twilight fades to darkness the lights of Antares, Mars and Saturn -- in that order from left to right -- appear low in the southwest. To Saturn's right and above, in the west, red giant star Arcturus shines. Look up to the top of the sky and left, southeasterly, to find the other first lights: Altair, Vega and Deneb, bright corners of the Summer Triangle.
One of the most charming and charged sights of the week occurs this evening when a robust crescent moon is positioned between Mars and Saturn. Moonset will be at 10:34 p.m.
Scorpius is recognized by an arc of stars to the left of Mars, with red super giant sun Antares further left. The moon will be close to this arc tomorrow and above Antares on Tuesday. Compared to the red heart of Scorpius, Mars has appeared golden rather than red or ruddy recently, a function of its relative nearness to Earth. It was closest for the year in April.
According to Stephen James O'Meara, writing in the current issue of Astronomy Magazine, "When Mars lies far from Earth, the planet's shrunken disk concentrates the warmth of its light." That is, it appears red.
Arcturus, the brightest star in the summer sky, was harbinger of spring planting when it first climbed above the east-northeast horizon flashing red-orange at nightfall in late March. Observing Arcturus in the west in evening twilight as cornucopias fill with all manner of harvests reawakens our awareness of seasonal rhythms on Earth reflected in the turn of the cosmos above.
To contact Judy Isacoff, go to: www.naturesturn.org
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