Science

Is HIV Evolving Into A Weaker Virus?

In parts of southern Africa, HIV has picked up mutations that slow down its ability to grow inside a person's blood. That's a good sign. But will it be enough to make a difference in the epidemic?

NASA Scrubs Launch Of Orion Spacecraft

After several issues, including high winds, stuck engine valves and a boat downrange of the launch site, the space agency said it would cancel today's planned launch of the new vehicle.