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May 15, 2025 By: LP DAAC The LP DAAC is pleased to announce the release of the Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Version 4 product suite. This suite provides high-resolution multispectral data from the ASTER instrument aboard NASA’s Terra satellite, coverin...

May 13, 2025 By: LP DAAC On November 28, 2024, at 14:20 UTC, one of Terra's power-transmitting shunt units failed. As a result, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument was put into Safe Mode . The Terra Flight Operations Team (FOT) resumed imaging with A...

Apr 18, 2025 By: LP DAAC A disturbance alert from 2023 was discovered in the Observational Products for End-Users from Remote Sensing Analysis (OPERA) Land Surface Disturbance Annual data from the Harmonized Landsat Sentinel-2 product Version 1 ( OPERA_L3_DIST-ANN-HLS_V1 ) for the year 2024. To ensu...

Apr 15, 2025 By: LP DAAC The LP DAAC will be transitioning to the Earthdata website in June 2025. While all the same information will be available, it may be located in different sections of the new site. We encourage users to view the new website and get familiar with the new layout. This announcem...

The LP DAAC will be migrating to the new Earthdata website in June 2025. As part of that process, the Frequently Asked Questions (FAQs) section currently found on the existing LP DAAC website will be relocating to the Earthdata forum . The LP DAAC FAQs are found under the Resources tab on the curren...

The OPERA Land Surface Disturbance Alert from Harmonized Landsat Sentinel-2 provisional (OPERA_L3_DIST-ALERT-HLS) Version 0 data product will no longer be available through NASA’s Earthdata Search as of April 24, 2025. Users are encouraged to transition to the OPERA_L3_DIST-ALERT-HLS Version 1 data ...

@jinyangwang11 Our science team replied with the following calculation for solar zenith angle.

cos(θz) = sin(φ)sin(δ) + cos(φ)cos(δ)cos(h)

θz = SZA

φ = latitude

δ = solar declination

h = hour angle

Best regards,
Janice

@jinyangwang11 While we are waiting for further guidance on your inquiry, there is ASTER documentation at this link that might be useful at: https://lpdaac.usgs.gov/products/ast_l1av003/#documentation
Thank you,
Janice

@jinyangwang11 I've forwarded your inquiry to our science team for further assistance.

Version 3.79 of the Application for Extracting and Exploring Analysis Ready Samples (AppEEARS) has been released. This release adds the VIIRS/NPP Land Surface Phenology Yearly L3 Global 500 m SIN Grid Version 2 (VNP22Q2.002) product to AppEEARS. About AppEEARS AppEEARS offers a simple and efficient ...