Title: The Signals of Opportunity P-band Investigation (SNOOPI): Next on the Pad and Ready for First Contacts
Presenting Author: Manuel A. Vega
Organization: NASA Goddard Space Flight Center
Co-Author(s): James Garrison, Rashmi Shah, Justin Mansell, Benjamin Nold, Roger Banting, Rajat Bindlish, Eric Smith, Kevin Smith, Jeffrey Piepmeier

Abstract:
The SNOOPI cubesat it set to launch in March 2024 onboard the Space-X 30 cargo resupply mission to the International Space Station (ISS). Deployment remains to-be-determined but expected in May 2024. The team has been working on readiness for commissioning and operations since it’s delivery and integration to the NanoRacks double wide deployer. This talk will give an update on preparations for operations, some of the challenges associated with it and also results from the early stages of commissioning with future plans for operations, if the deployment schedules allows. Recent advancements through airborne and tower experiments have provided fundamental proofs of concept of Signals of Opportunity (SoOp) remote sensing. However, adapting the SoOp measurement technique to an on-orbit environment presents three top risks, which can only be studied through spaceflight validation. First, reflected signal coherence at satellite altitude and velocity over widely varying surfaces needs to be characterized. Signal coherence is necessary to make precise phase observations, as required for SWE, and to achieve high signal strength in a specular reflection required by root zone soil moisture (RZSM). Second, robustness in the presence of RFI is a key advantage claimed for the SoOp technique. A thorough assessment of its effects on global scale observations is only possible from the vantage point of space and using the same observation geometry as a future Earth science mission. Third, prediction and tracking of the reflected signal in delay and Doppler space with the presence of uncertainty in the transmitter orbit position needs to be verified from receivers in space. SNOOPI was selected under the 2017 In-Space Validation of Earth Science Technologies (InVEST) program of the NASA Earth Science Technology Office (ESTO) to perform P-band observations from orbit with the goal of increasing the understanding of the top three risks identified. SNOOPI will utilize geosynchronous transmissions in two bands (244-270 MHz and 360-380 MHz).