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Full catalog/VISSRSMS1L1EHT
VISSRSMS1L1EHT·v001·dataset

Old weather-satellite imagery records (SMS-1)

VISSR/SMS-1 Level 1 Experimenter History Data V001 (VISSRSMS1L1EHT) at GES DISC
land NASA GES_DISC Level 1
In plain English

What it measures. Historic imagery from an early weather satellite, recording how much visible and infrared light came from segments of the Earth, plus details like time, location, and the satellite's position. Resolution was about 0.9 km in visible light and 8 km in infrared.

How it's made. Captured by the VISSR instrument on SMS-1, the first Synchronous Meteorological Satellite, which scanned the full Earth disk every 20 minutes back in 1974-1975.

How & where you'd use it. A rare archival record useful for historical weather and climate research; data exist for only nine days in 1974-1975, when SMS-1 supported a tropical Atlantic field experiment.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCESPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCE

Coverage & cadence

  • Time span1974-08-23 → 1975-02-17
  • Measured bySMS-1 (VISSR)
  • Processing levelLevel 1
  • Spatial extent-135, -90, 45, 90
  • StatusCOMPLETE

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

VISSRSMS1L1EHT is the Visible Infrared Spin-Scan Radiometer (VISSR) Level 1 Experimenter History Tape (EHT) data product from the first Synchronous Meteorological Satellite (SMS-1). Each data file contains a segment of the Earth with radiances that were measured in the visible (0.55 to 0.70 micrometer) and/or IR (10.5 to 12.6 micrometer) wavelengths with a spatial resolution of 0.9 and 8 km, respectively. Files also include time, geolocation, orbit, attitude, and telemetry information. A data file is structured with a header, followed by an IR scan line and then 8 visible scan lines (although some files only contain IR scans). Visible scans are at full resolution of 15288 pixels and a file will contain several hundred scan lines. IR scans are at 3822 pixels and up to a hundred scan lines. A full scan of the Earth was made every 20 minutes. Data for this product are only available for 9 days: 1974/08/23 (IR only), 1974/08/27 (IR only), 1974/08/31, 1974/09/01, 1974/09/02, 1974/09/05, 1974/09/24 (IR only), 1975/01/10, and 1975/02/17. The SMS-1 satellite was initially parked over the equator at longitude 45W on June 7, 1974 viewing the hemisphere below the satellite to support the GARP Atlantic Tropical Experiment (GATE). It was moved to its operational position at 75W on Nov 15, 1974 where it remained until GOES-1 was launched, after which SMS 1 was moved to 105W and placed in stand-by-mode as a backup to GOES-1 or SMS-2. The VISSR experiment was operated by the NOAA National Environmental Satellite Data and Information Service (NESDIS), as well as scientists from NASA Goddard Space Flight Center. This product was previously available from the NSSDC with the identifier ESAD-00126 (old ID 74-033A-01A).

Get the data

vissrsms1l1eht_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="VISSRSMS1L1EHT",
    version="001",
    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 GES_DISC
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.