Teardrop shape that created a tail flying low and parallel to the gound.A teardrop shape flying parallel to the horizon, flying close enough that we thought it might have been a helicopter at first. Bright, solid, teardrop that started emitting a tail as it moved in and out of samll clouds for a couple of seconds. Red and blue in the tail. The tail got longer and samll bursts of light appeared to pulse from the tail. It then entered another small cloud and never reappeared. We are husband and wife, never seen anything like this before. Husband is a ((deleted--senior academician)). Wife works in a technical/engineering field.