I was in my backyard in Potrero Hill in San Francisco at precisely 8pm on 3-18-13 when this occurred. I know this because I ran inside to call someone about what I saw and my phone said 8:01pm. I saw a stationary short cigar shaped glowing object with fuzzy edges high in the sky. I stared at it for about 30 seconds trying to figure out what it was then it disappeared, the light turned off like a light switch and it was gone. My heart started beating faster, I have never seen anything like this before.