Dear SMOSers
Raúl Díez-García from the SMOS Calibration Expertise Centre at ESAC (Spain) tells us that last Wednesday (September 6th 2017) SMOS was able to observe the monster X9-class solar flare. Se below the Sun’s brightness temperatures of this event. At the maximum, it almost reaches 21 million Kelvin which is kind of hot!. He provided the following charts:
SMOS observed temporal evolution of the Suns brightness temperatures during a solar flare (2017 09 06)
Find more details about the event here. I found it quite impressive!But this event was followed by another one as the same sunspot erupted again last Sunday (September 10th 2017). It also was quite strong, being X8 class. See below the observed BT, more than 4 million Kelvin.
SMOS observed temporal evolution of the Suns brightness temperatures during a solar flare (2017 09 10)
So if you are operating an L band radiometer double check your measurements for this period!