University of Colorado in Boulder

This Sunday night, we headed back to Mars: NASA's MAVEN spacecraft fired its six main engines, slowing down enough so it could be captured by the gravity of the red planet and go into orbit.

MAVEN, which stands for Mars Atmosphere and Volatile Evolution, is a distinctly un-sexy name for a project as cool as a sojourn to Mars. But whatever it's called, the probe is on a mission that should be of interest to everyone who likes living on Earth.

When you kiss your husband, does your dog try to get your attention? And does that mean that your dog feels jealous? Threatened? Or are we just imagining that?

Many if not all dog owners are sure that their pets have feelings. And we've known for a while that animals exhibit behaviors that look like jealousy, guilt and shame. But it's hard to find out what animals are really feeling. And researchers say that understanding that could give us valuable insights into human emotions, too.