As the Sun sets this week, we have a very nice view of four planets visible in an arc that spans the entire sky. About 45 minutes after sunset the sky is nicely fading to dark (around 8:45 to 9:00 here in San Francisco) and the four brightest objects in the sky take the stage, spanning from the northwest to the southeast. Nearest to the Sun is elusive Mercury in the northwest evening sky above the sunset point. Looking up and to the left you can't miss brilliant Jupiter, gradually dropping lower and lower in the evening sky in the constellation Gemini. Higher up and farther to the left of Jupiter is orange Mars, shining among the bright stars of Virgo. And finally in the opposite side of the sky from sunset is Saturn, emerging from opposition in the southeast part of the sky among the faint stars of Libra. From horizon to horizon the planets dominate the dusk sky, so if you have a good horizon step outside as the sky is fading and enjoy the four bright pinpoints of light that mark the path of the Solar System. In the fading light of dusk these are the first four objects you will be able to easily spot.
More details on Sky & Telescope and on Earth Sky.
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