Instead, garbage accumulated on the Space Shuttle is brought back to Earth when the vehicle returns from its scheduled mission. Trash collection day on the ISS, though, is a bit different. It isn't as easy as dragging a few cans to the curb. Whenever the Space Shuttle docks with ISS, bags and bags of refuse are loaded onto the Shuttle, which then returns to Earth. At times when the Shuttle isn't scheduled for a rendezvous , an unmanned supply vehicle called Progress is loaded with trash.
Progress never makes a landing, though.
It's designed to burn upon re-entry into the Earth's atmosphere. Housekeeping is the unglamorous side of living and working in space, but it's part of the job that needs to be done.