Keyboard command for DISTRIBUTING SPACE

Hello community!

Thanks for your help in the past - hoping you can help me with what seems like an easy one... The other day I was moving things around on a page and accidently discovered a keyboard command shortcut that was the the same as using the DISTRIBUTE SPACING command under the ALIGN MENU with the space set to zero inches. IOW, select two items, use the keyboard command and the two items move together. The problem - I was in the middle of something important and forgot to make a note of the command! Does anyone know what it is? I googled every option I could think of and I'm getting nothing. Any ideas? I'd appreciate it.