Budgetary highlights of decadal priorities
There are many programmatic and mission recommendations in the decadal survey. We address a handful below to highlight the general trend for new mission starts and scientific research support.
Flagship missions
The top decadal flagship mission priority, Mars Sample Return (MSR), is a major source of discrepancy between NASA’s projected funding and the decadal projections. According to FY 2025 projections, funding for MSR will decrease to $100 million per year in 2026 — far less than needed for the program. This decline represents the programmatic limbo in which MSR finds itself. NASA is looking for radical new ways to structure the program in order to control its costs (which the decadal assumed to be $5.3 billion over its lifetime, but had grown to nearly double that). Once a new plan for MSR is confirmed, its budget will need to grow in a way that does not put additional pressure on other important missions. The decadal recommendation was that MSR never exceeds more than 1/3 of the total planetary budget and that NASA should seek congressional budget augmentation if necessary. To the agency’s credit, MSR has not been canceled, and it remains the stated priority of the Planetary Science Division, even during this period of uncertainty.
The decadal’s Level and Recommended programs include the start of a Uranus Orbiter flagship mission. NASA is currently projecting a funding ramp-up to begin “formulation studies” of a Uranus orbiter beginning in FY 2027. The Level Program recommendation was to start the mission in FY 2028. NASA is thus projecting a plan consistent with the Level program, though we note that the funding ramp-up may not be rapid enough to launch before 2032.
Small- and Medium-class missions
The Level Program in the planetary decadal recommends one to two medium-class New Frontiers and five small-class Discovery missions be selected between 2023 and 2032. So far, no selections have been made. The current missions in development (VERITAS and DAVINCI for Discovery, Dragonfly for New Frontiers) are remnants of the prior decadal period and have all experienced delays and budget growth. The next call for new mission proposals is not expected until late 2026, with selections likely to be made the following year. Funding for future Discovery and New Frontiers missions doesn’t begin to increase in the FY 2025 President’s Budget Request until FY 2028, and is consistent with one new New Frontiers mission and one new Discovery mission. This makes NASA’s plans consistent with the Level Program for New Frontiers. NASA would have to follow the 2027 Discovery selection with a new Discovery mission selection per year for each subsequent year to meet the decadal recommendations, however. It’s not impossible (NASA has occasionally selected two Discovery missions at a time), but it will be difficult if the agency is also ramping up a Uranus Orbiter mission and working on MSR at the same time.
Planetary Defense
Planetary Defense is a relatively bright spot, funding-wise, in the current budget projections. Spending on this activity is expected to exceed both the Level and Recommended Programs outlined in the planetary decadal. This does not, however, mean that NASA is adding new missions and activities. NEO Surveyor, the priority mission outlined in the decadal, will cost more than expected to build and launch, which accounts for the additional funding. There is no funding for a follow-on planetary defense mission after NEO Surveyor, which was the recommendation of the Level and Recommended decadal programs.
Research and International Flight Opportunities
The planetary decadal recommends allocating 10% of the PSD budget to the Research and Analysis (R&A) program. If enacted, the amount provided for R&A in the President’s FY 2025 Budget Request would meet this benchmark. Future projections have R&A funding above 10% of the PSD topline through the end of the decade.
Funding for the “Planetary Other” activities, which includes management, mission-specific R&A, and contributions to international planetary exploration missions, meets or exceeds the Level and Recommended funding amounts, another positive sign for research funding. However, international contributions account for approximately 35% of the Planetary Other program for the FY 2023-2029 time period. EnVision and the Rosalind Franklin Rover, both ESA missions with major NASA contributions, account for a substantial amount of this funding.