Explanation of today's Solar Flux by Leif Svalgaard There are TWO numbers for the 10.7 flux. The observed number which is the ionosphere sees and is important for radio reception and the adjusted number which is what the Sun puts out. The difference comes about because the Earth's orbit is not circular and we are closest to the Sun in January [10.7 flux is 3.3% higher then] and furthest away in July [flux is 3.3% lower], so the the number you mention is 'artificially' too low simply because we are far from the Sun more or less right now. The 'real' number today is 66.7 [which is low enough], but still a bit higher than the 66.0 back in Oct. 22, 2007.