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Description

The Aqua MODIS (Moderate resolution Imaging Spectroradiometer) Level-1B (L1B) product includes calibrated and geolocated at-aperture radiances for 36 bands generated from MODIS Level-1A raw sensor counts. The radiances are provided in watts/m2/micrometer (µm)/steradian. The Aqua MODIS L1B product is a set three datasets (MYD02QKM, MYD02HKM, and MYD021KM) that are produced to address the three spatial-resolution variations: 250 m, 500 m, and 1000 m.

This landing page describes the 500-meter product with a short-name MYD02HKM. It provides 500-m calibrated radiances for the following 5 bands:

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<body>
<table style="width:50%">
<tr>
<th>Band</th>
<th>Wavelength</th>
</tr>
<tr>
<td>Band 3 (Blue)</td>
<td>0.459–0.479 µm</td>
</tr>
<tr>
<td>Band 4 (Green)</td>
<td>0.545–0.565 µm</td>
</tr>
<tr>
<td>Band 5 (Near-Infrared (NIR))</td>
<td>1.230–0.250 µm</td>
</tr>
<tr>
<td>Band 6 (Shortwave Infrared (SWIR))</td>
<td>0.628–1.652 µm</td>
</tr>
<tr>
<td>Band 7 (SWIR)</td>
<td>2.105–2.155 µm</td>
</tr>
</table>
</body>
</html>

Each 500-m band has 20 detectors in the along-track direction. The MYD02HKM product contains the following five Science Data Sets (SDS) besides geolocation fields for latitude and longitude, quality flags, error estimates, etc.

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<body>
<table>
<tr>
<th>SDS Variable</th>
<th>Long-name</th>
</tr>
<tr>
<td>EV_250_Aggr500_RefSB</td>
<td>Earth View 250M Aggregated 500M Reflective Solar Bands Scaled Integers</td>
</tr>
<tr>
<td>EV_250_Aggr500_RefSB_Samples_Used</td>
<td>Earth View 250M Aggregated 500M Reflective Solar Bands Number of Samples Used in Aggregation</td>
</tr>
<tr>
<td>EV_250_Aggr500_RefSB_Uncert_Indexes</td>
<td>Earth View 250M Aggregated 500M Reflective Solar Bands Uncertainty Indexes</td>
</tr>
<tr>
<td>EV_500_RefSB</td>
<td>Earth View 500M Reflective Solar Bands Scaled Integers</td>
</tr>
<tr>
<td>EV_500_RefSB_Uncert_Indexes</td>
<td>Earth View 500M Reflective Solar Bands Uncertainty Indexes</td>
</tr>
</table>
</body>
</html>

As evident from the above table, the 250-m (red and near-infrared) bands are also aggregated to 500 m through simple weighting functions that are applied to the data at their native resolution.

The v7.0 Aqua MODIS MYD02HKM in netCDF4 format represents the most current version of this product that has undergone around half-a-dozen reprocessing cycles in the last 2.5 decades. Each 500-m swath granule or data-file temporally spans 5 minutes and its image dimensions measure 4,060 lines (along-track direction) by 2,708 samples (cross-track direction). The v7.0 collection’s data record starts from July 4, 2002 (2002–185). Consult the MODIS L1B User Guide to understand how to convert the per-pixel scaled integers to radiance or reflectance.

Version Description

Aqua MODIS Version 7 Data Collection Processing and Reprocessing

Product Summary

Platforms
Aqua
Instruments
MODIS
Spatial Extent

N: 90 S: -90 E: 180 W: -180

Spatial Resolution
1 Kilometers x 1 Kilometers
Location
GLOBAL
Coordinate System
CARTESIAN
Granule Spatial Representation
GEODETIC
Temporal Extent
2002-07-04 to Present
Data Partner
MODIS Characterization Support Team (MCST), Biospheric Sciences Laboratory, Earth Sciences Division, Science and Exploration Directorate, Goddard Space Flight Center, NASA (NASA/GSFC/SED/ESD/HBSL/BSB/MCST) ,
L1 and Atmosphere Archive and Distribution System,Biospheric Information Systems Branch, Hydrospheric and Biospheric Sciences Laboratory, Earth Sciences Division, Science and Exploration Directorate, Goddard Space Flight Center, NASA (NASA/GSFC/SED/ESD/H
Concept ID
C3861620488-LAADS
Data State
ACTIVE
Number of Files/Granules
1362702
Processing Level
1B
Published
Science Keywords
Infrared Radiance ,
REFLECTED INFRARED ,
Visible Radiance

Citation

Citation is critically important for dataset documentation and discovery. This dataset is openly shared, without restriction, in accordance with the EOSDIS Data Use and Citation Guidance.

Copy Citation

MODIS Science Team. (2024). MYD02HKM MODIS/Aqua Calibrated Radiances 5-Min L1B Swath 500m [Data set]. NASA Level 1 and Atmosphere Archive and Distribution System Distributed Active Archive Center. https://doi.org/10.5067/MODIS/MYD02HKM.007 Date Accessed: 2026-03-17

File Naming Convention

Syntax: ESDT.AYYYYDDD.HHMM.CCC.YYYYDDDHHMMSS.Format
Example: MYD02HKM.A2025031.0400.007.2025177004130.nc

• MYD02HKM = ESDT/Shortname
• AYYYYDDD = Acquisition Year and Day of Year
• HHMM = Acquisition Hour and Minute
• CCC = Version ID of the data collection
• YYYYDDDHHMMSS = Processing year, Day-of-year, UTC time (hour, minutes, seconds)
• Format = File format suffix, which in the above case represents netCDF4

Documents

USER'S GUIDE

ALGORITHM THEORETICAL BASIS DOCUMENT (ATBD)