NASA - National Aeronautics and Space Administration

NASA announced Tuesday a Grand Challenge focused on finding all asteroid threats to human populations and knowing what to do about them.

The challenge is a large-scale effort that will use multi-disciplinary collaborations and a variety of partnerships with other government agencies, international partners, industry, academia, and citizen scientists.

› NASA Asteroid Initiative

 › Asteroid Initiative Request for Information

 › Grand Challenge Information

After an extensive year-and-a-half search, NASA has a new group of potential astronauts who will help the agency push the boundaries of exploration and travel to new destinations in the solar system. Eight candidates have been selected to be NASA's newest astronaut trainees.

  Space Station Live: 2013 Astronaut Class

This week marks the anniversary of two significant events in the history of space exploration -- the flight of Valentina Tereshkova 50 years ago on June 16 and of Sally Ride 30 years ago on June 18.

As the first women from their respective countries to fly in space, Tereshkova and Ride helped to usher in an era of equality in human spaceflight. Since their historic flights, 55 women (and counting) have journeyed into space.

NASA's NuSTAR mission has been busy studying the most energetic phenomena in the universe. Recently, a few high-energy events have sprung up, akin to "things that go bump in the night." When one telescope catches a sudden outpouring of high-energy light in the sky, NuSTAR and a host of other telescopes stop what they were doing and take a better look.

When we get sick, our immune systems kick into gear to tell our bodies how to heal. Our T cells -- white blood cells that act like tiny generals -- order an army of immune cells to organize and attack the enemy. Microgravity studies aboard the International Space Station are helping researchers pinpoint what drives these responses, leading to future medical treatments on Earth.