The first color images of Pluto's atmospheric hazes, returned by NASA's New Horizons spacecraft last week, reveal that the hazes are blue.
Most materials swell when warm, and shrink when cool. But some weird materials do the opposite. Although thermal expansion, and the cracking and warping that often result, occurs everyday -- in buildings, electronics, and almost anything else exposed to wide temperature swings -- physicists have trouble explaining why solids behave that way. New research into a material that has negative thermal expansion may lead to a better understanding of why materials change volume with temperature at all.
Cigarette smoking and heavy alcohol use cause epigenetic changes to DNA that reflect accelerated biological aging in distinct, measurable ways, according to research. The researchers estimated biological age using a previously validated epigenetic "clock" , calculated the difference between biological age and chronological age, and assessed the relationship between tobacco and alcohol use and premature aging.