Roy et al. (2025) The next Landsat: Mission turning point?

Identification

• Journal: Remote Sensing of Environment
• Year: 2025
• Date: 2025-10-16
• Authors: David P. Roy, Michael A. Wulder, Noel Gorelick, Matthew C. Hansen, Sean P. Healey, Patrick Hostert, Justin Huntington, Volker C. Radeloff, T. A. Scambos, Crystal Schaaf, Curtis E. Woodcock, Zhe Zhu
• DOI: 10.1016/j.rse.2025.115087

Research Groups

• Center for Global Change and Earth Observations, Department of Geography, Environment, & Spatial Sciences, Michigan State University, USA
• Canadian Forest Service (Pacific Forestry Centre), Natural Resources Canada, Canada
• Cantrip AG, Switzerland
• Department of Geographical Sciences, University of Maryland, USA
• USDA Forest Service Rocky Mountain Research Station, USA
• Earth Observation Lab, Geography Department, Humboldt-Universität zu Berlin, Germany
• Desert Research Institute, Division of Hydrologic Sciences, USA
• SILVIS Lab, Department of Forest and Wildlife Ecology, University of Wisconsin-Madison, USA
• ESOC/CIRES, University of Colorado Boulder, USA
• School for the Environment, University of Massachusetts, USA
• Department of Earth and Environment, Boston University, USA
• Department of Natural Resources and the Environment, University of Connecticut, USA
• Members of the 2018–2023 Landsat Science Team (LST)

Short Summary

This correspondence raises awareness about the pending decision on the Landsat Next (LNext) mission architecture, outlining the originally envisioned advanced observation requirements derived from extensive user needs assessments and contrasting them with a recently proposed descoped mission that would only meet existing Landsat-9 capabilities. The paper advocates for the original LNext design to ensure future scientific and operational capacity for Earth observation.

Objective

• To raise community awareness about the pending decision on the Landsat Next (LNext) mission architecture.
• To outline the observation requirements originally envisioned for LNext and how they were derived from comprehensive user needs assessments.
• To provide context for evaluating the restructured and descoped LNext capability now being considered.

Study Configuration

• Spatial Scale:
  • Original LNext design: 10 meters and 20 meters for Visible/Near-Infrared/Shortwave Infrared (VSWIR) bands, 60 meters for Thermal Infrared (TIR) bands.
  • Restructured/descoped mission: 30 meters for VSWIR, 100 meters for TIR (similar to Landsat-8/9).
  • Swath width: 164 kilometers (±7.2° from nadir) for the original LNext design.
• Temporal Scale:
  • Original LNext design: Global land coverage every 6 days (three satellites).
  • Restructured/descoped mission: 16-day temporal revisit (single satellite).
  • Equatorial crossing time: 10:10 am ±5 minutes for original LNext; 10:00 am to 10:15 am for alignment with Sentinel-2.
  • Mission lifetime: Landsat-9 has 10 years of consumable resources and a 5-year sensor design life. LNext nominal launch 2031.

Methodology and Data

• Models used: Not explicitly stated as models used in this correspondence, but the paper discusses capabilities that LNext would enable, such as improved atmospheric correction, cloud masking, evapotranspiration assessment, and land surface temperature and emissivity estimation using multi-TIR band temperature and emissivity separation algorithms.
• Data sources:
  • User needs assessments: 379 interviews with U.S. civil federal agency users (agriculture, ecological and land change science, forestry, geological, natural hazard, water, cryosphere experts).
  • Landsat Advisory Group (LAG) outreach to non-federal, non-LST stakeholders (commercial industry, non-profit, international organizations, state and local governments, academia).
  • Expert feedback gathered from targeted review panels (agriculture, cryosphere, vegetation, ecology, inland and coastal water, temperature and emissivity, evapotranspiration, atmospheric correction and cloud masking).
  • Input and recommendations from the 2012–2017 and 2018–2023 Landsat Science Teams (LSTs).
  • Reference to existing satellite data from Landsat-8, Landsat-9, Sentinel-2, MODIS, and VIIRS for context and comparison.

Main Results

• The original LNext mission design, informed by extensive user needs, proposed a constellation of three sun-synchronous satellites providing global land coverage every 6 days.
• This design included 26 VSWIR and TIR bands with significantly improved spatial (10 meters/20 meters VSWIR, 60 meters TIR), temporal (6-day revisit), and spectral resolution compared to previous Landsat missions.
• These enhancements were intended to enable new and improved applications, including water quality, crop production, forest management, snow dynamics, and mineral mapping, alongside improved atmospheric correction and land surface temperature/emissivity estimation.
• Due to proposed 2026 U.S. budget reductions, an alternate, descoped LNext architecture is under consideration, which would consist of a single satellite with sensor characteristics and performance similar to the 30-year-old capabilities of Landsat-8 and 9.
• This descoped mission would only provide a 16-day temporal revisit and risks lower radiometric quality than current Landsat-8/9 missions, failing to meet the advanced capabilities advocated by the Earth Observation user community.
• The final decision on the LNext architecture is pending, with significant implications for the future scientific and operational capacity of the Landsat program throughout the 2030s.

Contributions

• This correspondence serves as a critical and timely intervention to inform the scientific and user community about the potential descoping of the Landsat Next mission.
• It synthesizes and clearly articulates the comprehensive user needs and expert recommendations that shaped the original, advanced LNext design.
• It highlights the significant scientific, societal, and economic value that would be lost if the descoped mission is adopted, providing a strong argument for maintaining the originally envisioned capabilities.
• It provides a detailed comparison of the proposed advanced LNext capabilities versus the descoped alternative, offering essential context for evaluating the pending decision.

Funding

• The USGS co-sponsored and funded the USGS–NASA Landsat Science Team.
• The U.S. Sustainable Land Imaging (SLI) Program committed in 2016 to extend the Landsat record.
• The U.S. Congress provided funds to initiate LNext with costs equivalent to Landsat-8 when adjusted for inflation.

Citation

@article{Roy2025next,
  author = {Roy, David P. and Wulder, Michael A. and Gorelick, Noel and Hansen, Matthew C. and Healey, Sean P. and Hostert, Patrick and Huntington, Justin and Radeloff, Volker C. and Scambos, T. A. and Schaaf, Crystal and Woodcock, Curtis E. and Zhu, Zhe},
  title = {The next Landsat: Mission turning point?},
  journal = {Remote Sensing of Environment},
  year = {2025},
  doi = {10.1016/j.rse.2025.115087},
  url = {https://doi.org/10.1016/j.rse.2025.115087}
}