You may have noticed that the magazine you're holding has a little more heft to it. That's because, for the first time, we are accepting advertisements. Our publisher, the Natural Resources Defense Council (NRDC), has generously footed the bill for this magazine for nearly 30 years. But ever-rising publishing costs confronted OnEarth with a clear choice: either we spend more money on postage and printing and less on reporting, or we look for additional sources of funding. We chose the latter course because it will allow us to continue producing award-winning journalism.

Our advertisers are companies seeking to expand the market for green products and services or to promote green practices in their business conduct. But their appearance in OnEarth does not in any way signify an endorsement by us or by NRDC.

You'll notice other changes as well. We've updated our appearance: new logo, new typography, a new design for every section of the magazine. We wanted to refurbish, to call out to a new generation -- our future -- and to improve the aesthetic experience for our loyal, longtime readers, too.

Together, these changes signify a new beginning of sorts. As I scanned the issue before it went to press, I was struck by how many stories seemed to herald something new -- for better or for worse, or perhaps both in the case of our cover story. We asked Robin Marantz Henig, a contributing writer for the New York Times Magazine, to delve into the microcosmos of nanotechnology, which is wondrously poised to transform our everyday lives. At the nano level, the fundamental properties of some substances can change -- from insulators to electrical conductors, for instance, or from fragile to tough. On a practical level, this means new treatments for cancer, a new generation of solar panels, and more mundane inventions such as bandages that disinfect and food containers that keep leftovers fresher. Gee whiz! But as this stuff enters our water system, our food supply, even our cells, does anyone know whether it's safe? Apparently not. Henig's piece, which focuses on nanosilver, offers the first in-depth look at the risks posed by this rapidly emerging, soon-to-be three-trillion-dollar industry.

A few pages later you'll encounter another phenomenon that probably will come as news to most of you. The petroleum industry has figured out another way to scrape oil from the earth and in the process erase a vast Canadian wilderness (no kidding -- vast meaning the size of Florida) while burning preposterous amounts of fossil fuels to produce one of the dirtiest forms of energy known to man. The source of this new oil: tar sands, huge subterranean deposits of bitumen that Calgary-based journalist Andrew Nikiforuk describes as "the biggest pile of hydrocarbons outside Saudi Arabia."

A new technology, a new energy craze, a new look, and soon (stay tuned) a new Web site. I hope this profusion of newness serves you well, dear reader. Please don't hesitate to tell us what you think.

Douglas S. Barasch