The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five state-of-the-art instrument sensor systems operating on the Terra spacecraft. The Terra satellite was launched on December 18, 1999. Terra flies in a sun-synchronous polar orbit, crossing the equator at 10:30 a.m. Eastern Standard Time (EST).
ASTER utilizes a unique combination of wide spectral coverage and high spatial resolution in the visible near-infrared through shortwave infrared to the thermal infrared regions. It is a partnership between NASA, Japan's Ministry of Economy, Trade and Industry (METI), the National Institute of Advanced Industrial Science and Technology (AIST) in Japan, and Japan Space Systems (J-spacesystems).
ASTER data contributes to a wide array of global change-related application areas including vegetation and ecosystem dynamics, hazard monitoring, geology and soils, hydrology, and land cover change.
ASTER filenames (i.e., the local granule ID) follow a naming convention which provides useful information regarding the specific product.
In this example, the filename AST_L1T_00309122019230211_20190913112425_15725 indicates:
The ASTER Product Long Name (i.e. Collection-Level) convention provides useful information regarding the product.
In this example, ASTER L1B Registered Radiance at the Sensor V003:
The ASTER products distributed from LP DAAC are produced from on-demand data acquisition requests and are not categorized by regular temporal ranges.
The ASTER instruments acquire data in three native spatial resolutions:
1Band 3 nadir (3N) and band 3 backward-looking (3B) allows capability of creating a Digital Elevation Model when both bands are acquired.
LP DAAC distributes ASTER land data processed to Level 1 through 3:
|Band||Reflected Range (µm)||Spatial Resolution (m)||Band Explanation/Uses|
|1||0.52 - 0.60||15 m||Visible and Near-Infrared|
|2||0.63 - 0.69||15 m||Visible and Near-Infrared|
|3N||0.78 - 0.86||15 m||Visible and Near-Infrared|
|3B||0.78 - 0.86||15 m||Visible and Near-Infrared|
|4||1.600 - 1.700||30 m||Shortwave Infrared|
|5||2.145 - 2.185||30 m||Shortwave Infrared|
|6||2.185 - 2.225||30 m||Shortwave Infrared|
|7||2.235 - 2.285||30 m||Shortwave Infrared|
|8||2.295 - 2.365||30 m||Shortwave Infrared|
|9||2.360 - 2.430||30 m||Shortwave Infrared|
|10||8.125 - 8.475||90 m||Thermal Infrared|
|11||8.475 - 8.825||90 m||Thermal Infrared|
|12||8.925 - 9.275||90 m||Thermal Infrared|
|13||10.25 - 10.95||90 m||Thermal Infrared|
|14||10.95 - 11.65||90 m||Thermal Infrared|
The ASTER products have two sources of metadata: the embedded Hierarchical Data Format (HDF) metadata, and the external Earth Observing System Data and Information System (EOSDIS) metadata, otherwise known as the EOSDIS Core System (ECS) metadata. The generated ECS .met file is the external metadata file in XML format that is delivered to the user along with the ASTER product. For georeferencing purposes, use the values delineated in the embedded HDF metadata. Other product-specific and core metadata can be referred from either source.
Refer to the ASTER User Handbook for L1B products and the User Guide for higher level products regarding details on the individual core and product metadata attributes.
Data access options such as Data Pool, Earthdata Search Client, and EarthExplorer can be found under Tools.
An HDF-EOS file contains information essential for NASA data access tools and services. Most software programs that can process standard HDF files can read an HDF-EOS file. However, it is difficult for a standard HDF call to interpret HDF-EOS geolocation or temporal information without further knowledge of the file structure.
Certain open source tools and proprietary tools are available for use with ASTER HDF-EOS products:
Open Source Tools
If ASTER data are not available in an area of interest, the satellite sensor can be tasked to attempt to capture the area by submitting a Data Acquisition Request (DAR).