Grand Canyon rising If the geology of the Grand Canyon dates back to 70 million years ago “Grand Canyon’s age pushed back,” (SN: 1/12/13, p. 15), that would be around the same time the Rocky Mountains were being pushed up by the subduction process originating off the western continental coast. Could the lifting of the Colorado Plateau be related to the lifting of the Colorado Rockies? Joe Flynn, Spanaway, Wash. The timing of the Colorado Plateau’s uplift remains fairly controversial, including whether it occurred all at once or in several discrete stages. But many geologists thi... (p. 31)

The surface of the moon may be covered with deep layers of fluffy material into which landing vehicles could sink out of sight…. Research so far has shown that loose particles hit by meteoroids settle down into the moon’s rock or mineral surface. This surface becomes exposed to radiation and breaks down into fine particles of dust. The dust coagulates into larger and larger clumps…. Observed characteristics of a cement powder have been found to match the reflection characteristics of the lunar surface. The conclusion is that the surface of the moon is likely to be composed of cement powd... (p. 4)

April 5 – 6 Texas A&M University hosts a physics and engineering festival. See a bubble show or meet an astronaut and two Nobel laureates. More at bit.ly/SFtamu2013 April 22 Deadline for entries to the Society of Vertebrate Paleontology illustration awards, honoring the best in art depicting dinosaurs and other ancient life. See bit.ly/SFpaleo2013 (p. 4)

EARTH IN ACTION Alexandra Witze ponders Earth’s odds in “When an asteroid heads for Earth, it’s time to reconsider those doomsday plans.” MOLECULES Nanoparticles (below, blue) detect viruses (pink) in “Synthetic nanomaterial can recognize viruses.” HEALTH & ILLNESS Allergic people became able to tolerate up to a full glass of milk. See “Therapy for milk allergy offers hope, and caution.” Pregnant women taking an omega-3 fatty acid have bigger babies. Read “Fish oil component boosts newborn health.” (p. 4)

SN Prime | March 4, 2013 | Vol. 3, No. 9 Chicken Little is right. The sky is falling. The million-plus people living in Chelyabinsk, Russia, got that message on February 15, when a space rock some 17 meters across detonated over their homes. People rushed to the windows in wonderment as a blaze of light arced through the sky; seconds later many of them got a face full of glass shards. It was the most damaging cosmic collision since 1908, when an even bigger asteroid chunk blew up over Siberia. (In an era before YouTube and dashboard cameras, it was weeks before tales trickled out of reindeer...

It has taken longer than previously credited for the kind of people now on earth to rise to become what we know as modern man. Evidence now is that man and his cultures extend beyond two million years into the past. Radioactive dating has given new time determinations for human ancestors and evolution in the dim anthropological past. The latest “clock” or dating method measures the amount of the chemical element argon in rocks to determine their age…. The date of the earliest skeletal remains, generally conceded “human,” those of Zinjanthropus discovered in Olduvai Gorge, Tanganyika,... (p. 4)