star trails!

no, this is not a rain shot. this is the result of sitting in balcony at the cold weather for half an hour and holding the shutter for several minutes. i failed many times in the middle of holding the shutter and the longest time i could hold was 7 minutes and 30 seconds (this image). i could barely feel my fingers (whether i used my gloves) after finishing this shot. this ne is not good as the other star trails that has been post by others but this is the best i could take without a remote control (am i the first to do this?) and the limited area that i could take from the balcony.