NASA's PACE Mission to reveal Earth's ocean and climate secrets is set to launch on Falcon 9

Photo credit Dennis Hlavsa for SpaceX FrontPage

   The satellite houses three instruments: the Ocean Color Instrument (OCI) and two polarimeters to measure the atmosphere’s aerosol composition. Unlike current remote sensing satellites, which measure five to seven colors, the OCI will measure the brightness of more than 200 colors, from ultraviolet to infrared. Scientists use the ocean’s color to identify the abundance of phytoplankton, which live in the upper 200 meters of the water column. Greener waters typically mean that more of these chlorophyll-containing microbes are present.

   “The amount of light at each wavelength is directly impacted by how much of each type of plankton is in the water,” explained Alison Chase, an optical oceanographer at the University of Washington and a member of the NASA PACE Science and Applications Team. This is because different pigments (like yellow to orange carotenoids) and cell structures absorb and scatter light differently, she said.

   Different types of phytoplankton interact with the ocean and atmosphere in varying ways, said Jeremy Werdell, a project scientist for PACE and an oceanographer at NASA. Ultimately, however, phytoplankton “form the base of the aquatic food chain. They are responsible for bringing carbon dioxide out of the atmosphere,” he said.

   PACE could also help answer questions about the role of phytoplankton in the carbon cycle as the world warms. “We certainly don’t know a lot yet about how different phytoplankton community groups at the surface impact carbon flux on large spatial scales,” Chase said. 

   Larger phytoplankton species such as diatoms live in the upper ocean but rely on cold, nutrient-rich water that upwells from the deep, for example. Warming waters could affect ocean currents, limiting the flow of nutrients. If these conditions occur, “big phytoplankton won’t have what they need to grow,” Chase said.

    PACE will help scientists monitor these communities across entire ocean regions. Those data can then be used to estimate carbon flux and predict what may happen to carbon levels if those communities change, Chase said.

    PACE will produce so much information that it will be a challenge to use it all at first, Werdell said. “The beauty of this mission in my mind is that it’s information we can grow into in order to understand the interconnectedness of this full Earth system.”
    The Falcon 9 rocket will deliver PACE to an orbit approximately 420 miles (677 km) above Earth surpassing the International Space Station's orbit by about 70 percent. Liftoff is currently scheduled to take place during the dramatic hour of 1:33 a.m. EST (0633 GMT) on Tuesday (Feb. 6). The spacecraft will launch atop a SpaceX Falcon 9 rocket from Florida's Cape Canaveral Space Force Station. You can watch the launch live at NASA's website as well as SpaceX’s X (formaly known as Twitter). Coverage will begin at 12:45 a.m. EST (0545 GMT).

However, the launch date might be subject to change due to weather conditions or technical
reasons, potentially extending to February 8.