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Full catalog/NISAR_OE
NISAR_OE·v1·dataset

Where the NISAR satellite traveled in orbit

NISAR Orbit Ephemeris
land NASA ASF Level 1A active XML
In plain English

What it measures. The precise record of where the NISAR satellite was in its orbit at each moment, stored as 'state vector' files. It comes in several flavors ranging from quick forecasts to highly precise after-the-fact positions.

How it's made. Generated for the NASA-ISRO NISAR radar mission as tracking files, with accuracy improving from early forecasts to final precise versions as more tracking data comes in.

How & where you'd use it. A behind-the-scenes building block: scientists need to know exactly where the satellite was to correctly place and process its radar images, so most people use it indirectly rather than on its own.

What's measured

SPECTRAL/ENGINEERING › PLATFORM CHARACTERISTICS › ATTITUDE CHARACTERISTICS

Coverage & cadence

  • Time span2025-07-30 → ongoing
  • Measured byNISAR (L-SAR, S-SAR)
  • Processing levelLevel 1A
  • Spatial extent-180, -90, 180, 90
  • FormatsXML
  • StatusACTIVE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The NASA-ISRO Synthetic Aperture Radar (NISAR) Orbit Ephemeris collection contains the state vector files for the NISAR mission. The collection includes multiple accuracy levels defined by the product type where FOE=Forecast Orbit Ephemeris, NOE=Near real-time Orbit Ephemeris, MOE=Medium precision Orbit Ephemeris, and POE=Precise Orbit Ephemeris.

Get the data

nisar_oe_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="NISAR_OE",
    version="1",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from ASF
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.