A very bright, white, spherical light abruptly appeared in the night sky, and minimized until it became a pinprick and disappeared.

Outside, I thought a house security light went off in my peripheral, and as I turned to look, I found that the light came from overhead.  In the sky, there was an incredibly bright, white, spherical light, and as I got a good look at it, I reasoned out that it was not a helicopter (Believe me, I wanted to think it was simply a helicopter with its lights on.) Just as I spoke up to get my father to look, the light minimized until it was a pinprick in the sky, and moved away so quickly that I could not follow it.