Alaska Satellite Facility
Delivering Remote Sensing Data Since 1991

Product Description


SMAP provides global measurements of soil moisture and its freeze/thaw state. In September 2015, mission managers determined that the SMAP radar instrument active mode failed on July 7 (see NASA news story). SMAP receive-only radar data are available subsequent to July 7 on an experimental basis.

The SMAP instrument incorporates an L-band radar (VV, HH, and HV polarizations) and an L-band radiometer (V, H, and 3rd and 4th Stokes parameter polarizations). The Level 1 radar data products will be archived and distributed by the Alaska Satellite Facility, and the radiometer and Level 2-4 data products will be archived and distributed by the National Snow and Ice Data Center.

The SMAP orbit is a 685-km altitude, near-polar, sun-synchronous 6 a.m./6 p.m., 8-day exact repeat, frozen orbit.

To obtain high spatial resolution, the radar employs range and Doppler discrimination. Unfocused SAR (synthetic aperture radar) processing yields spatial resolution that varies from 1 km to 3 km over the outer 70% of the swath ('high-resolution' radar).

The data products will conform to the HDF-EOS5 standard, and metadata will conform to the ISO 19115 standard.

Data Citation

Citing SMAP Level 1 Datasets

Cite datasets in publications such as journal papers, articles, presentations, posters, and websites. Each SMAP Level 1 dataset has an assigned DOI. Please also send a copy of publications that cite datasets or tools obtained through ASF to

SMAP data [year of data acquisition] (NASA). Dataset: [name of dataset]. Retrieved from ASF [add URL if print publication:] DAAC [day month year of data access]. DOI: [doi]

SMAP data 2015 (NASA). Dataset: SMAP L1C_S0_HiRes. Retrieved from ASF DAAC 7 December 2015. DOI: 10.5067/NVVUJ0MNG3PN

Scroll or click for list of SMAP Level 1 datasets and their DOIs.

Crediting SMAP Imagery

Include appropriate credit with each image shown in publications such as journal papers, articles, presentations, posters, and websites. For more information, see NASA guidelines.

Imagery, primary or alteredCredit: NASA data [year of data acquisition].Credit: NASA data 2014.
Imagery, derivativeCredit: [Name of image creator or institution, as appropriate], [year of image creation], contains NASA data [year of data acquisition].

Credit: Jones, D., 2015, contains NASA data 2015.

SMAP Level 1 Datasets and DOIs

L1A Radar10.5067/DM0U37IYZ6NK

Data Citations and Acknowledgements

Data Access


Data Service Name: Vertex
Data Service Description: Search, visualize, subset, and download data in HDF5
Data Service Access URL:

Data Service Name: Alaska Satellite Facility Application Programming Interface (API)
Data Service Access URL:

Data Service Name: Earthdata Search
Data Service Description: This application allows you to search, discover, visualize, refine, and access NASA Earth Observation data.
Data Service Access URL:

Product Summary


Short Name(s):  SPL1C
Version:    1-3
Format    HDF5
Spatial Coverage:   (90.0 N to -90.0 S; 180.0 E to -180.0 W)
Temporal Coverage: 13 April 2015 to 7 July 2015

Data Resolution:
Latitude Resolution: 1-3 km
Longitude Resolution: 30 km
Temporal Resolution: 3 days

Get SAR Data

Get SAR Data

Select and download SAR data online using Vertex.

Use the ASF API for downloading SAR data via a command line.