Calling Occupants of Interplanetary Craft

I noticed this odd prism in the sky tonight. Can anyone tell me what it is please?

I'm no good at science, or physics, or what ever it is that tells you what these things are. Hated them with a passion at school.

I'd love to understand things better, but when you have a husband who knows a reasonable amount and a daughter and son who can fill you in on the rest, you don't really need to stretch your brain.

In second year, I had Mr McDonald for General Science (Yes, the same Mr McDonald). We all filed into the classroom, and sat at our tables. He came round the room, grinning like an idiot. and plonked a little tray with a lid on it in front of us all.

He got back to the front of the class, and said, "okay, lids off". I gingerly edged the lid off to be confronted by a big cow's eye looking back at me.

I got my chair and moved it to the middle of the corridor.

"Come on Helen", he said, "it's nothing more than half a pound of mince".

"That", I said, "Is why I don't eat mince".