It's important, with climate change, landfills, hazardous waste, the health of humans and other species, future generations and the health of the planet.

We want to keep NASA front and center and capture the imagination of the viewer. And the Web is a good way to reach kids. In fact, it may be the best way.

Unfortunately, we should have explicitly said that, by all means, people should continue to answer e-mails within their areas of expertise, but we did not. It was never anyone's intention to muzzle anybody or restrict information from going out to the public.