Five planets, were visible with the naked eye. Mercury, Venus, Mars, Saturn and Jupiter.
Also, Mars, Venus and Saturn formed a near perfect triangle in the night sky [See Link].
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Four of them (Venus, Saturn, Mars, and Mercury) formed an eye-catching knot during the first week of May. On May 10th and 11th, Venus and Mars drew so close together that they resembled a bright double star.
Venus, Saturn and Mars were closely grouped together in the sky that evening. You can read the entire article on SpaceWeather.com. Check the related links section