The SpaceX Drago cargo spacecraft is expected to splash down on Wednesday off the Florida coast after successfully leaving the International Space Station on Monday.
The capsule arrived about a month ago to deliver about two tons of scientific investigations and supplies to the space station.
NASA astronauts Frank Rubio and Josh Cassada completed two spacewalks in December to install the new solar array wings to boost the ISS's electrical production capability for the next decade.
The spacecraft also carried holiday food and treats, and eight CubeSats from teams in Brazil, the United States, Canada, Italy, and Taiwan that will be deployed later outside the space station.
The Dragon spacecraft will be returning high-pressure oxygen and nitrogen gas tanks that will be refilled on the ground for a future launch.
It will also be returning a catalytic reactor for the station's life support system, a pressure control and pump assembly for the urine processing system, multifiltration beds for the station's water processor, a mass spectrometer and hydrogen sensor, and potable water dispenser filters.
The items will be refurbished to one day return to the International Space Station.
