Monday, March 2, 2015

Dawn Comes to Ceres

This Friday is going to be an exciting day in space exploration!

I just got finished watching NASA’s JPL briefing on the status of the Dawn spacecraft mission, and I loved it! And as Bill Nye says: “When you’re in love, you want to tell the world!”

The Dawn spacecraft was launched in September 2007, and in 2011 it became the first spacecraft to orbit a body in the main asteroid belt: it spent over a year examining the giant asteroid Vesta, making wonderful observations about its surface features and geologic activity. Vesta is the second-largest object in the asteroid belt, but Dawn wasn’t quite satisfied with that.

On Friday, it will reach Ceres, the largest object in the asteroid belt, and earn two other unprecedented titles: the first spacecraft to orbit two different worlds, and the first spacecraft to reach and investigate a dwarf planet.

Tuesday, January 13, 2015

Happy Accidents: Beneficial Mutations in Humans

A while back, I was talking with a group of young students about evolution and natural selection, and I was teaching them about the role of mutations when I was asked an interesting question that I failed to answer.

The concept of mutations can be tough to grasp, because mutation sounds like a really bad thing, and indeed it often is. A mutation is essentially an accident in your DNA, and while most of them are harmless, most of the rest have unfortunate side effects. And yet mutation is one of the driving forces of evolution: natural selection weeds out the bad accidents and encourages the good ones, and life changes through the generations.

Which brings me to this question I was asked: Are there examples of good mutations in humans?