The SpaceX commercial resupply services, CRS-4, mission to the International Space Station was delayed due to rain, NASA reported. The U.S. space agency had scheduled the launch of the Dragon spacecraft atop a Falcon 9 rocket for Saturday, but has rescheduled it for Sunday at 1:52 a.m. EDT.

“Because of weather conditions that violated the rules for launching, SpaceX has postponed its planned launch of its Falcon 9 rocket carrying the Dragon spacecraft. It is SpaceX’s fourth commercial resupply services mission to the International Space Station,” NASA said in a statement. The Falcon 9 rocket was vertical on the launch pad at the Cape Canaveral Air Force Station in Florida before the launch was scrubbed.

The Dragon spacecraft will be carrying 4,885 pounds of cargo, including 1,380 pounds of crew supplies, as well as science experiments, technology demonstrations and the International Space Station Rapid Scatterometer, or ISS-RapidScat. The ISS-RapidScat will be mounted to the exterior of the space station and will bounce microwaves off the ocean’s surface to measure wind speed.

Elements of the payload aboard SpaceX’s Dragon spacecraft will enable a multifaceted study of the Factors Contributing to Food Acceptability and Consumption, Mood and Stress on Long-Term Space Missions, or Astro Palate. To make a long story short, the study will explore ways dietary habits may be able to reduce the stress associated with space travel.

Another endeavor, the NanoRacks-Ames Fruit-Fly Experiment, will study the effect of space flight on oxidative stress, the buildup of harmful material in cells that can lead to disease.

Possibly the most interesting piece of equipment to be flown to the space station this weekend is Made In Space Inc.’s 3D printer. The 3D Printing in Zero-G experiment “will use relatively low-temperature plastic feedstock to demonstrate that a 3D printer works normally in space, the first step toward establishing an on-demand machine shop in space, a critical enabling component for deep-space crewed missions and in-space manufacturing” (PDF).

Meanwhile, NASA announced Tuesday SpaceX will receive a $2.6 billion contract to ferry astronauts to the space station, bringing manned launches back to the U.S. in 2017.

You can watch the NASA SpaceX launch live stream, beginning Sunday at 12:45 a.m. EDT. below:

Broadcast live streaming video on Ustream