After a monthlong delay, SpaceX’s 25th NASA-contracted resupply mission is prepared for launch to the International Space Station (ISS) late July 14 from the agency’s Kennedy Space Center in Florida.
The SpaceX Falcon 9 rocket and its Dragon resupply capsule—loaded with a 5,800-lb. cargo that includes a new climate science investigation—is scheduled to lift off at 8:44 p.m. EDT. The weather outlook is favorable, though forecasters will be monitoring the cloud cover and small chance of rain.
Plans for a June 10 launch were delayed by the detection of elevated concentrations of monomethyl hydrazine propellant vapors in an isolated region of the Dragon capsule’s propulsion system. That led to replacement of a Draco thruster valve inlet joint and an examination of other nearby hardware for damage that prompted replacement of the main parachutes that are deployed when the spacecraft returns to Earth.
The new launch date was also set as early as possible following a period of high solar beta angle in relation to the ISS orbital plane at the time of the planned rendezvous and docking, factors that can lead to thermal control and power generation concerns.
With an on-time launch, the Dragon freighter is to rendezvous with the ISS on July 16 for an automated docking with the orbital lab’s U.S. segment Harmony module’s forward-facing port at 11:20 a.m. EDT.
In addition to crew supplies and ISS equipment, the large payload includes a wide range of new science investigations and technology development activities.
Those include the new Earth Surface Mineral Dust Source Investigation (EMIT), which will employ a NASA Jet Propulsion Laboratory (JPL)-developed imaging spectroscopy sensor to measure the mineral composition of dust harbored in the Earth’s most arid regions. Dust-borne minerals can rise high into the atmosphere and travel long distances, impacting weather, longer range climate and vegetation.
More specifically, dark minerals can absorb heat that is cast around them, while lighter colored minerals can cool the areas they contact. Blowing dust affects air quality and when on the Earth’s surface affects the rate of snow melt and the health of phytoplankton in the oceans.
“Interestingly, the Earth has a mineral dust cycle,” Rob Green, EMIT’s principal investigator from JPL, told a NASA July 13 prelaunch news briefing.
“The minerals are the particles that make up rocks. And in the arid land regions of the planet under conditions of high winds, these minerals get launched into the atmosphere where they can heat or cool the planet. They can form clouds, and there are a host of other interactions they have with our system,” he said. “We are going to close a gap in knowledge about those mineral dust source regions of our planet.”
Currently, about 5,000 different sites globally have been analyzed by personnel physically gathering samples.
Once EMIT has been deployed at the ExPRESS Logistics Carrier 1, an external mount for science payloads located on the long ISS solar power truss. The goal is to reach 1 billion direct observations using the instrument’s spectroscopy. The first data should begin to reach the research team for dissemination at the end of September, Green says.
The Dragon mission will also deliver five small satellites to the ISS for future deployments into low Earth orbit, including the Massachusetts Institute of Technology’s BeaverCube, another climate research initiative. Weighing less than 13 lb. and equipped with electric propulsion, the BeaverCube small satellite is equipped with multiple cameras to image the Earth’s oceans and gather thermal images of cloud tops and the ocean’s surface.
Once deployed from the ISS by astronauts, BeaverCube is to provide data for climate researchers and weather forecasters, including improvements in understanding how ocean concentrations of phytoplankton help to generate atmospheric oxygen.
“We have to hope with such a small and simple spacecraft we can pave the way to have more CubeSats and more spacecraft that are small and simple for tracking temperature and the climate change around the entire globe so we can better understand and tackle this chilling feature,” Paula do Vale Pereira, BeaverCube mechanical engineering and integration lead, told the prelaunch briefing.
“Research onboard the space station spans every major discipline, including biology and human research, the physical sciences, Earth and space sciences, educational outreach and also development and demonstration of new technologies,” noted Heidi Parris, NASA’s ISS program associate scientist. “All of that research is being done with a single goal in mind, and that is to bring benefits to us as the human race.”
An example of the research diversity headed to the ISS aboard the resupply mission is Genes in Space-9, an ongoing, ISS National Laboratory-sponsored investigation into the cell-free production of proteins in the absence of gravity. It is part of a technology that could provide a compact, low-cost tool for medical diagnostics, the on-demand production of medicines and vaccines as well as environmental monitoring of astronauts on long space exploration missions.
Related Content
