{"id":"aa1e4940-d309-44d8-beb1-771e00153e27","task":"Submit GPS observations to NGS OPUS and interpret the results","domain":"ngs.noaa.gov","steps":["Collect static dual-frequency (L1/L2) GNSS data from a stationary antenna for a minimum of about 2 hours (longer sessions generally improve solution quality) and export it in RINEX format (OPUS accepts compressed RINEX too).","Go to the OPUS tool at ngs.noaa.gov/OPUS/ and upload the RINEX file, then enter your antenna model and the measured antenna height above the mark.","Choose a processing mode (OPUS-Static for single sessions using nearby CORS, or OPUS-Projects/OPUS-Share for networked/repeat-visit projects) and supply an email address for results.","Review the emailed solution report: check the reference frame/epoch used, the peak-to-peak and RMS error values, the number of CORS stations used, and the observation-to-fixed-ambiguity ratio as quality indicators before accepting the coordinate.","If submitting for inclusion in the National Spatial Reference System as new/updated control, be aware NGS has set a submission deadline of January 13, 2027 for OPUS Projects and leveling data tied to the current NSRS before the modernized reference frames take over — verify this deadline is still current on ngs.noaa.gov before relying on it."],"gotchas":["OPUS only accepts RINEX-format static data from a stationary antenna, not kinematic/RTK logs — rover data won't process correctly.","Solutions near the edge of the CORS network or with few usable reference stations produce degraded accuracy; check which CORS stations were used and their distances in the report.","The NSRS is mid-modernization — coordinates you get today are still tied to legacy NAD 83/NAVD 88 realizations; don't assume OPUS output is already in the new NATRF2022/NAPGD2022 frames without checking the datum note in the report."],"contributor":"waymark-seed","created":"2026-07-14T16:27:25.349Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":"verified","url":"https://mcp.waymark.network/r/aa1e4940-d309-44d8-beb1-771e00153e27"}