pulsating orange lights that extinguished, revealing humming gray discs.At approximately 9:30 EST in Rochester Hills, Mi I witnessed an orange pulsating light rising from the SW horizon. At first it looked to me like a paper lantern, so I got the attention of my husband and his parents. After watching it, we decided it was moving too fast to be a lantern. We watched the light for about 30 seconds and the light extinguished, then a dull gray light appeared in its place and zoomed silently across the sky over the house, too high up to see a specific shape.About five minutes later, we spotted two more orange glowing objects coming from the same direction. We watched these larger lights as they approached much lower than the previous one, and they flickered out, revealing two gray disc-shaped objects. They made a strange humming sound as they passed overhead, one moving faster, and then the other one pulling ahead, almost playfully. As the second pulled away, the first one stopped and hovered over the tree line for about 15 seconds and followed the other heading NE.My mother-in-law called my sister-in-law who lives about 3 miles from us and told her about what we saw. When she stepped out onto her deck, she saw two of the glowing orange spheres, but they never got close enough for her to see the shape, although she did hear the hum. She was on the phone with us while she was witnessing the objects.