Hi there, After a quick look at the recent reports you were referring to, it seems that one of the main "reasons" for this theory is the claim that solar irradiance (the amount of light coming form the Sun) has increased over the past number of years. This is not actually true as you can see from this plot: http://data.giss.nasa.gov/gistemp/2010summer/figure5.gif Time in years is on the horizontal axis and the total solar irradiance is on the vertical axis. You can see that as recently as 2010 (not that long in "Sun" years), the total solar irradiance was way down at the minimum level. That means that the total solar irradiance is pretty much at the lowest level that its been at for many years. So that contradicts the claims being made about global warming on Mars. I can't explain why there might be global warming on Mars, if there is at all, but I can tell you that the total output radiation from the Sun is not to blame. Claire