Level-0 Production Data Set: The Level-0 data which are sent from EDOS are packetized in the CCSDS format as shown in Figure 2-1. These packets are classified into four groups of data according to an APID (Application Process Identification) in the primary header of each packet. The group 1 data contain the data for VNIR bands 1 and 2. The group 2 data contain the data for VNIR bands 3N and 3B. The group 3 data contain the data for all SWIR bands. The group 4 data contain the data for all TIR bands. Each data group include science image data, instrument supplement data and spacecraft ancillary data.

ASTER is allocated the 64 APIDs that lie within the decimal equivalent range of 256 - 319. Different APIDs are allocated depending on data content (image data, instrument supplement data, or spacecraft ancillary data), data groups and operation modes (observation mode, calibration mode and test mode).

The packets are sorted out with the time tag data in the secondary header and then sorted out in the order of the image data, the instrument supplement data and the spacecraft ancillary data with different APIDs. Some packets contain both the supplement data and the ancillary data in the same packet. In a group with the same APID the packets are sorted out in the order of sequential counter data in the primary header.

Figure 2-1 CCSDS Level-0 data packet format