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Terra/MODIS direct broadcast geolocation failure

Posted: Fri Jul 09, 2021 11:34 am America/New_York
by deum
It seems that Terra/MODIS data received through direct broadcast (my colleagues have their own receiving station) is somehow corrupted and contains no valid attitude and ephemeris data required for further processing. All the Level1A data files contain fill values for all the geolocation fields and fields for various angles etc. The problem is actual for about two weeks already and is crucial for near real time data processing because there are no NRT attitude and ephemeris files for Terra, and objective atteph files may appear several (or many) hours after the real data.
I'm sure the problem can be solved because the NRT data for Terra/MODIS is provided by LANCE. So, the question is whether NRT atteph data for Terra can be found anywhere or are there any other ways to fix it?
The processing software used is MODISL1DB_SPA, version 1.8.

Thank you very much!

Bset regards, Mikhail.

Re: Terra/MODIS direct broadcast geolocation failure

Posted: Tue Aug 03, 2021 2:48 pm America/New_York
by ASDC - David W.
Hi Mikhail,

Sorry for the long delay in responding to your reply. I think I may have found NRT atteph data for Terra. Please see the link below. On the "Overview" tab, click the "Data Archive" link to find the file(s) you need to process your data.

https://ladsweb.modaps.eosdis.nasa.gov/ ... 3#overview

As far as the direct broadcast problem, where the attitude and ephemeris data is corrupted, I'll reach out to a group more familiar with this problem and see if they have a solution.

Thank you,

David :)
NASA ASCD User Services

Re: Terra/MODIS direct broadcast geolocation failure

Posted: Tue Aug 03, 2021 5:01 pm America/New_York
by ASDC - David W.
Hi Mikhail,

I think I found more information which may be related to direct broadcast geolocation failure. On June 29, 2021, the Terra satellite suffered a power failure which effected the MODIS data. Please see the following link for more details.

https://ladsweb.modaps.eosdis.nasa.gov/ ... /?id=65540

Hopefully since then you have been able to receive Terra/MODIS data through direct broadcast.

Sincerely,

David :)

NASA ASDC User Services