Year-end lists inevitably leave room for debate and criticism, and ours is no exception. It was an eventful year, and we relied on voting among Scientific American editors to cull our candidates. Any of these notable achievements were certainly worthy but didn't make the final cut. The runners-up were:

• The discovery in South Africa of a new hominid, called Australopithecus sediba, that could be a lost member of our family tree 

• The emergence of hydraulic fracturing, or "fracking," a controversial way to recover natural gas trapped in deep rocks 

• The detection of an atmosphere of a "super-Earth" and other signs of potentially habitable worlds around other stars 

• The recommendation by an advisory committee for the U.S. to approve genetically modified salmon

• The vote by the U.S. Federal Communications Commission to maintain an open, neutral Internet, although service providers still could prioritize content 

• The introduction of the iPad, a disruptive technology displacing netbook computers but opening up new opportunities for software developers 

• The latest sign of climate change, namely, the NASA conclusion that 2010 will be the hottest year on record, with the world's average temperature reaching 14.65 degrees Celsius, 0.03 degree higher than the previous record year of 2005 

Our Facebook fans also chimed in with their top choices, many of which overlap with ours—plus quite a few more.

And as some Facebook fans also pointed out, scientific progress rarely tends to happen in nice, discrete annual chunks. Major discoveries in 2010 could turn out to lead nowhere, and unappreciated studies could end up being watershed moments. We can say for sure, though, that 2010 was hardly a boring year for science and technology.

Click here to view the countdown of our Top 10 Science Stories of 2010