NASA Selects Four Earth Science Mission Proposals for Further Study

NASA has selected four mission proposals for its first Earth System Explorer missions. These selections mark the beginning of Phase A studies, each lasting one year and receiving $5 million for mission design refinement.

The agency will then select two of these proposals for development, with a target launch timeline: one to launch by 2030 and the another by 2032. Each mission is capped at a cost of $310 million, excluding launch expenses.

The chosen proposals cover a diverse range of Earth science domains:

• Stratosphere Troposphere Response using Infrared Vertically-Resolved Light Explorer (STRIVE) aims to comprehensively measure temperature, composition, and aerosols from the upper troposphere to the mesosphere.

• Ocean Dynamics and Surface Exchange with the Atmosphere (ODYSEA) proposes a mission to concurrently measure ocean currents and winds, enhancing our understanding of ocean-atmosphere interactions.

• Earth Dynamics Geodetic Explorer (EDGE) plans to provide detailed three-dimensional structures of terrestrial ecosystems, including the measurement of glaciers, ice sheets, and sea ice.

• The Carbon Investigation (Carbon-I) mission seeks to provide crucial measurements of various greenhouse gases, including both natural and human-made sources, to improve our understanding of the carbon cycle.

These missions signify the inception of NASA's Earth System Explorer program, initiated in response to the 2018 Earth science decadal survey. This program, positioned between directed Earth science missions and smaller Earth Venture projects, aims to deliver competitively selected missions that are both cost-effective and scientifically impactful.

Fox emphasizes the critical need for comprehensive data and scientific research in tackling climate-related issues.

"The proposals represent another example of NASA’s holistic approach to studying our home planet," - Nicky Fox, NASA's Associate Administrator for Science.

In a strategic move to avoid overwhelming institutions involved in Earth science research, NASA plans to stagger announcements of opportunity (AOs) for Earth System Explorer and Earth Venture projects. The next Earth System Explorer AO is slated for release in 2029, with a mission launching in 2037.

Moreover, NASA is restructuring its Earth System Observatory, intending to split large missions into smaller, more manageable ones. As part of this effort, the agency announced plans for the Atmosphere Observing System – Cloud (AOS-Cloud) mission, with a cost cap of $400 million (excluding launch) and a launch readiness date of 2031.

In parallel, NASA is advancing a smaller Earth science technology demonstration mission named the Gravitational Reference Advanced Technology Test In Space (GRATTIS). Led by the University of Florida, GRATTIS aims to test a new sensor designed to measure Earth's gravitational field. John Conklin, principal investigator of GRATTIS, emphasized the mission's potential in providing vital insights into Earth's water and ice dynamics, essential for monitoring droughts, groundwater reserves, and sea level rise.

GRATTIS will utilize an Aries spacecraft bus provided by Apex Space and is scheduled to launch on a SpaceX Transporter rideshare mission no earlier than October 2026. This mission represents a significant step forward in Earth science technology, promising valuable contributions to our understanding of Earth's complex systems.