Today, Saturday the 26th, Discovery will be docking at the ISS. The time to watch is about 1pm eastern time today, which is 11am mountain time. The shuttle will start with the Rendezvous Pitch Manuever (RPM) before it docks, allowing the crew on the ISS to take high-resolution photos of the heat shield of the orbiter. This is one of the measures started after the Columbia disaster in an effort to detect any major damage to the orbiter’s heat shield before re-entry.
To find out EXACTLY what the astronauts onboard will be doing today, check out this pdf.
If anyone is interested, I could do a later post on how exactly two spacecraft moving at over 17,000 mph can hook up together in space.