Olber's Paradox asks why the sky is not a sheet of white. Since just the galaxy we are in has 50 stars for every person currently on earth traveling to us at all time, how can it ever get dark when there are billions of galaxies all containing stars? 

It isn't just a visible light mystery, something is amiss in the ultraviolet Universe also.  We can't explain all of the light in the cosmic budget.

Sociology is too uncontrolled to be meaningful science but controlled scenarios don't lead to realistic behavior. 

The Virtual Environment Navigation lab at Brown University thinks they can bridge the gap between them.

They have developed a wireless virtual reality system to study a phenomenon that scientists don't yet understand: how pedestrians interact with each other and how those individual behaviors, in turn, generate patterns of crowd movement. It's an everyday experience for all kinds of animals everything from people to ants. 

Researchers have measured the highest level of ultraviolet radiation ever recorded on the Earth's surface.

These extraordinary UV fluxes, observed in the Bolivian Andes only 1,500 miles from the equator, are far above those normally considered to be harmful to both terrestrial and aquatic life, though that has to be calibrated. A beach in Brazil also has radiation levels far above safe levels, yet people visit it for that reason. And plane flights provide even more radiation than that. 

Adults with extreme obesity have increased risks of dying at from cancer, heart disease, stroke, diabetes, and kidney and liver diseases, according to results of an analysis of data pooled from 20 large studies of people from three countries.

The analysis led by researchers from the National Cancer Institute (NCI) found that people with class III (or extreme) obesity had a dramatic reduction in life expectancy compared with people of normal weight.

There is nothing more natural than sexes. Throughout evolution, living things have repeatedly developed physically distinct genders but how this happens has been a puzzle.

A discovery in the multicellular green alga Volvox carteri may be the revelation of the genetic origin of male and female sexes, showing how they evolved from a more primitive mating system in a single-celled relative.

California leads the country in creating science policy by opposition; if Republicans are against it, California will pass it. Taxpayers are swimming in debt and wondering why they wasted $3 billion paying a bureaucrat $500,000 a year to redistribute money on human embryonic stem cell research, with nothing to show for it, and their landmark cap-and-trade system for regulating greenhouse gases  has led to 50 percent higher utility rates for consumers but has done nothing for climate change - all of America's drop in CO2 was caused by natural gas uptake in the rest of the nation.