Sentinel-3 SLSTR L1B

About Sentinel-3 SLSTR L1B Data

Mission information

SENTINEL-3 is a European wide-swath, medium-resolution, multi-spectral imaging mission designed to monitor ocean surface topography as well as land and sea surface temperature. The satellite hosts four instruments: the Sea and Land Surface Temperature Radiometer (SLSTR), the Ocean and Land Colour Instrument (OLCI), a Sar Radar Altimeter (SRAL) and a Microwave Radiometer (MWR). Sentinel-3A was launched on 16 February 2016 and its twin Sentinel-3B on 25 April 2018.

The SLSTR instrument was designed to provide data continuity with the Advanced Along Track Scanning Radiometer (AATSR) instrument flown on Envisat. The main objective of the instrument is to provide global sea surface temperature measurements with zero bias and uncertainties of ± 0.3 K, as well as land surface temperature readings and fire monitoring.

SLSTR has an along-track dual view scanning technique, enabling acquisitions at nadir and along-track in the backward direction, which include measurements of two blackbody calibration targets and a Visible Calibration Unit for high accuracy. The radiometer has 9 channels ranging from the visible and near-infrared (VNIR) to the thermal infrared (TIR). Two additional bands (active fire bands) in the TIR are optimised for fire monitoring with an increased dynamic range to prevent saturation. In single-view mode, SLSTR has a spatial resolution of 1 km, with less than half a day revisit time (with Sentinel-3 A and B) and a swath of 1400 km. In dual-view mode, a 500m resolution is reached, but only covering a swath of 744 Kilometers and with a daily revisit time.

Level 1B provides calibrated and ortho-geolocated Top Of Atmosphere (TOA) radiances for the 6 VNIR/SWIR bands (S1 to S6) and TOA brightness temperatures for the thermal IR and fire channels (S7 to S9 and F1, F2).

More information:

Basic facts

Spatial resolution500 m or 1 km per pixel
SensorSea and Land Surface Temperature Radiometer (SLSTR), 11 bands: 3 VNIR bands, 3 SWIR bands, 5 thermal IR bands.
UnitsRadiance: (Note that Sentinel Hub returns reflectance) / Brightness temperature: K.
Revisit time< 0.9 days at the equator with 2 satellites
Spatial coverageLand and coastal areas where the solar zenith angle < 80º
Data availabilitySince May 2016
MeasurementTop of the atmosphere (TOA) radiance and brightness temperature
Common usage/purposeClimate change monitoring, vegetation monitoring, active fire detection, land and sea surface temperature monitoring.

Attribution and use

EU law grants free access to Copernicus Sentinel Data and Service Information for the purpose of the following use in so far as it is lawful: a) reproduction; b) distribution; c) communication to the public; d) adaptation, modification and combination with other data and information; e) any combination of points a to d.

See more details on the use of Copernicus Sentinel data and service information

Tracing based on Sentinel imagery is allowed for commercial purposes as well.

Acknowledgment or credit: Contains modified Copernicus Sentinel data [Year] processed by Sentinel Hub.

Accessing Sentinel-3 SLSTR Data

To access data you need to send a POST request to our process API. The requested data will be returned as the response to your request. Each POST request can be tailored to get you exactly the data you require. To do this requires setting various parameters which depend on the datasource you are querying. This chapter will help you understand the parameters for S3SLSTR data. To see examples of such requests go here, and for an overview of all API parameters see the API Reference.

Endpoint Locations

ServiceNotes since May 2016 since May 2016

Data type identifier: S3SLSTR

Use S3SLSTR as the value of the parameter in your API requests. This is mandatory and will ensure you get Sentinel-3 SLSTR L1B data.

Filtering Options

This chapter will explain the object of the S3SLSTR process API.


Sets the order of overlapping tiles from which the output result is mosaicked. The tiling is based on ESA's Product Dissemination Units for easier distribution.

mostRecentthe pixel will be selected from the most recently acquired tileIf there are multiple products with the same timestamp then NTC will be used over NRT.
leastRecentthe pixel will be selected from the oldest acquired tileIf there are multiple products with the same timestamp then NTC will be used over NRT.
leastCCpixel is selected from tile with the least cloud coverage meta-dataNote that "per tile" information is used here.


Filters the acquisition orbit direction.

ASCENDINGthe pixel will be selected from the ascending node.Default value.
DESCENDINGthe pixel will be selected from the descending node.


Filters the acquisition by view.

NADIRthe image acquired by the nadir viewing scanner will be selected.Default value.
OBLIQUEthe image acquired by the oblique (rear) viewing scanner will be selected.

Processing Options

This chapter will explain the object of the S3SLSTR process API.

upsamplingDefines the interpolation used for processing when the pixel resolution is greater than the source resolution (e.g. 100m/px with a 500m/px source).NEAREST - nearest neighbour interpolation
BILINEAR - bilinear interpolation
BICUBIC - bicubic interpolation
downsamplingDefines the interpolation used for processing when the pixel resolution is lower than the source resolution (e.g. 800m/px with a 500m/px source).NEAREST - nearest neighbour interpolation
BILINEAR - bilinear interpolation
BICUBIC - bicubic interpolation

Available Bands and Data

This chapter will explain the bands and data which can be set in the evalscript input object: Any string listed in the column Name can be an element of the input.bands array in your evalscript.

NameDescriptionWavelength centre (nm)Resolution (m/px)
S1Cloud screening, vegetation monitoring, aerosol554.27500
S2NDVI, vegetation monitoring, aerosol659.47500
S3NDVI, cloud flagging, pixel co-registration868500
S4Cirrus detection over land1374.80500
S5Cloud clearing, ice, snow, vegetation monitoring1613.40500
S6Vegetation state and cloud clearing2255.70500
S7SST, LST, Active fire37421000
S8SST, LST, Active fire108541000
S9SST, LST12022.501000
F1Active fire37421000
F2Active fire108541000
dataMaskThe mask of data/no data pixels (more).N/A*N/A**

*dataMask has no wavelength information, as it carries only boolean information on whether a pixel has data or not. See the chapter on Units for more.
**dataMask has no source resolution as it is calculated for each output pixel.

For more about Sentinel-3 SLSTR bands, visit this ESA website.


The data values for each band in your custom script are presented in the default units as specified here. In case more than one unit is available for a given band, you may optionally set the value of input.units in your evalscript setup function to one of the options. Doing so will present data in that unit. The Source Format specifies how and with what precision the digital numbers from which the unit is derived are encoded. The Typical Range indicates what values are common for a given band and unit, however outliers can be expected.

For optical bands, REFLECTANCE is the default and only unit and for brightness temperature bands the default and only unit is KELVIN.

BandUnitSource FormatTypical RangeNotes
Optical bands
S1 - S6
REFLECTANCEUINT160 - 0.4Higher values in infrared bands. Reflectance values can easily be above 1.
Brightness temperature bands
S7 - F2
KELVINUINT16250 - 320Roughly -20 to +50 C. Can reach outside this range in extreme environments.
dataMaskN/ABoolean0 - no data
1 - data


All mosaicking types are supported.

Scene Object

This chapter will explain the evalscript evaluatePixel scene object.

The scene object contains the following properties:

Property nameDescriptionType
dateScene sensing timeJavaScript Date object
tileIdUnique scene identifierInteger (e.g., 2027449)
tileOriginalIdSentinel 3 tile identifierString (e.g., EODATA/Sentinel-3/SLSTR/SL_1_RBT/2020/06/20/ S3A_SL_1_RBT____20200620T205839_20200620T210139_20200620T232024 _0179_059_314_0720_LN2_O_NR_004.SEN3)
idxScene numberInteger (e.g., 2)

Catalog API Capabilities

To access Sentinel 3 SLSTR product metadata you need to send search request to our Catalog API. The requested metadata will be returned as JSON formatted response to your request.

Endpoint Locations

ServiceNotes since May 2016 since May 2016

Collection identifier: sentinel-3-slstr

Query extension

  • eo:cloud_cover cloud cover percentage
  • eo:gsd ground sample distance (resolution)

Distinct extension

  • date
  • sat:orbit_state


S3SLSTR examples