A light in the sky caught my eye, it was blinking red and green so i checked the flight radar and there was nothing and i had just seen the air ambulance heading southwest not long before that and this light was north. in the binoculars i could just see the lights but no shape to it at all. when i started recording it disappeared for a minute the reappeared at a higher altitude, became very bright then faded out and reappeared again at a lower altitude. this went on for about 20 minutes until it finally just vanished. i have no idea what this is.