I opened my back door and i immediately saw something in the sky. i've never seen an aircraft give off a green light, it's usually red blinking lights. this was different. the object was pulsating green and white lights. i watched the object for about 10 minutes and i realised i should be recording it. i videoed it for about 3 and a half minutes and then stopped. i went upstairs to try and get a better look but the object must have been behind a neighbouring house. i came back downstairs and viewed the object for a further 10 minutes (approximately). the object was slowly moving around the night sky and moved diagonally upwards to my right. i went back upstairs where i got a better view of the object. i went to get my phone as it's got a better camera on it and as i sighted the object again it seemed to be considerably dimmer. and then it just disappeared. i could see stars with the naked eye but not in the video. all that can be seen in the video is what i've been talking about.