My mistake Bob, you're right
I thought the pressure on Mars was only 6mm or less. I think I must have truly believed something I read - like posted on the net, by someone very adamant (like Donald) eh? Anywhere above the triple point, liquid is very possible, though I suspect wind and humidity play a real role as well. The ice in my windy refrigerator at 760 mm sure sublimates fast! But Mars isn't nearly so dry as I was led to believe. Thanks for the insight. I enjoy your posts. I'll try not to be so gullible!