NPP
Country: United States · Also known as: 2011-061A
Live Position
Ground Track · Last 90 Minutes
Upcoming Passes · Over Your Location
About This Satellite
Suomi National Polar-orbiting Partnership, abbreviated Suomi NPP, launched on October 28, 2011. It helped establish the polar-orbiting weather and environmental observations continued by the Joint Polar Satellite System. Its scientific value lies in calibrated measurements, not simply in the attractive global images made from them.
Weather observations beyond the cloud photograph
A polar-orbiting mission samples changing parts of Earth instead of hovering over one weather system. For this catalog, that distinction explains why successive passes move across the map. The useful output is a collection of observations that can be combined with other spacecraft and forecast models, rather than a continuous local webcam.
Position is not an instrument-health report
A new NPP TLE updates the trajectory shown here. It does not verify that every instrument is delivering valid data at that instant. Use the instrument and product sources below when assessing a particular observation; use this page to understand the spacecraft that collected it.
Mission reference: NOAA: A Decade of Discovery for Suomi NPP. Editorial review: .
VIIRS: many wavelengths, many environmental questions
The Visible Infrared Imaging Radiometer Suite has 22 imaging and radiometric bands. Its measurements support products covering clouds, ocean colour, fires, vegetation, snow, and ice. A band is a wavelength range, not an additional satellite. Combining bands reveals contrasts that a conventional visible-light photograph can miss; the chosen product determines what those contrasts mean.
Reference: NOAA: VIIRS on Suomi NPP.
CrIS and ATMS: looking through atmospheric layers
The Cross-track Infrared Sounder and Advanced Technology Microwave Sounder complement each other. CrIS measures infrared spectra, while ATMS uses microwaves that penetrate much cloud cover. Their observations support vertical temperature and moisture profiles. This is why a weather satellite can improve a forecast even when its contribution is not displayed as a familiar cloud image.
Reference: NOAA: Cross-track Infrared Sounder.
Reading this orbital snapshot
Based on TLE epoch: 2026-09-05. Estimated altitude ranges from 825 km at perigee to 829 km at apogee, a difference of 4 km. The orbital period is about 101.4 minutes. Eccentricity 0.00028 indicates a nearly circular path. In a two-body approximation, perigee speed is 1.00 times apogee speed. These are mean-element estimates, not instantaneous measurements. Distance per orbit uses an ellipse approximation.
Saved build snapshot. If a valid TLE is retrieved, this explanation and the orbit panel update together. Otherwise this dated snapshot is retained.
Ground track is not sensor coverage
An inclination of 98.80 degrees implies approximate geocentric ground-track limits of 81.2 degrees north and south. This is a retrograde orbit, moving against the direction of Earth rotation. The plotted line marks the point beneath the object. It does not represent camera coverage, radio reception, or a guaranteed visible pass.
Accuracy and missing information
The introductory record describes the build snapshot. The orbital snapshot explanation and orbit panel share any successfully retrieved TLE; check the displayed epoch. Reentered objects retain historical data only. Mission history is not rewritten by TLE updates. TLE/SGP4 positions are predictions and can change after maneuvers or updated observations. The 14-day stale-data cutoff is a display safeguard, not an accuracy guarantee. Local passes are geometric predictions, not a visibility forecast. No verified operator or mission status means unknown, not active. Do not use this catalog for collision avoidance or operational flight decisions.
Catalog sources: CelesTrak SATCAT: NORAD 37849 · GCAT: S37849 (source update 2026 Sep 4 2345:57). Supplementary metadata: SatNOGS DB, retrieved 2026-09-05T12:57:25.375Z. Page assembled 2026-09-15. GCAT phase codes describe trajectory phases, not mission health.
Learn more: TLE data · Perigee and apogee · Ground tracks · JOT (Jewawud Live Orbital Map)