What does Julian Date refer to in the BlackMarble product?

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luopeixian
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What does Julian Date refer to in the BlackMarble product?

by luopeixian » Tue Feb 15, 2022 10:15 pm America/New_York

In Page 9 of the VIIRS BlackMarble UserGuide, it says:
' ...The filename VNP46A1.A2015001.h08v05.001.2017012234657.h5 indicates:
(2) A2015001: Julian Date of Acquisition (A-YYYYDDD);
(5) .2017012234657: Julian Date of Production (YYYYDDDHHMMSS)...'

I wonder what Julian Date refers to here. Does the Julian Date here equal to UTC time?
Wikipedia says that the Julian date (JD) of any instant is the Julian day number plus the fraction of a day since the preceding noon in Universal Time. Julian dates are expressed as a Julian day number with a decimal fraction added. For example, the Julian Date for 00:30:00.0 UT January 1, 2013, is 2 456 293.520 833.
Therefore, the normally mentioned Julian Date is a number. However, the Julian Date in BlackMarble is in date format, so I wonder what it means.

Looking forward to your answers! Thanks!

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Re: What does Julian Date refer to in the BlackMarble product?

by LAADS_UserServices_M » Thu Feb 17, 2022 9:13 am America/New_York

Yes, all UTC times.
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