I think I know what he's on about
back in the old badastronomy forum yaohua2000 used to type these count-down clocks into the thread title

topics such as a launch or $%^ is now only 8,976 km from Mars and aproaching fast
He done a thread title such as Cassini is about to arrive at Saturn and is now *** kilometres away and the number would re-load and update

or he'd do a topic such as Deep impact is 5 hrs from the comet...and the title would continue to count-down or re-fresh every few mins

I'm sure there must be another way for him to do his countdown clock