It seems like it just didn’t switch to IR since the band is black, not white. So it’s not really blank, it just had nothing to see.
But why it didn’t switch?
It looks like it did switch, it’s bairly visible on this image due to the noise, but you can see it switching channels from IR right at the top. Maybe the switching is inverted? I could not find any more good APT images from this time on satnogs though sadly
It seems like it just didn’t switch to IR since the band is black, not white. So it’s not really blank, it just had nothing to see.
But why it didn’t switch?
It looks like it did switch, it’s bairly visible on this image due to the noise, but you can see it switching channels from IR right at the top. Maybe the switching is inverted? I could not find any more good APT images from this time on satnogs though sadly