Dr. Sean Conley, the president's physician, said he had been concerned about "possible rapid progression of the illness," following two developments on Friday.
Data from a 2008 survey of the lunar surface indicates the presence of a form of rust that requires oxygen and water to form—neither of which the moon has enough of.
"This is the first step in trying to understand the evolution of Mars' atmosphere," Håkan Svedhem, ESA's TGO Project Scientist, told Newsweek.
Researchers find first direct evidence of a "glacial oxygen pump," which they say extended an essential lifeline to the simple life forms that inhabited the Earth at the time.
"There are many many reasons to be concerned…but a risk to the world's oxygen supply is not one of them," Allison Mills from Michigan Technological University told Newsweek.
How far would you go to keep a lie under wraps?
A witness told dispatchers the man had fallen to the ground and his wheelchair was on fire.
Eighty percent of all fish in Münster's Aasee lake have already died.
Scientists say the biggest extinction event ever was caused by comparable rate of cO2 emissions to those seen today.