Science has been a part of Discovery’s DNA since we first launched in June 1985, and it continues to be a priority for us…and one of our neighbors down the road in D.C. In December, Science Channel debuted Science Presents DNews, nightly nuggets of science goodness hosted by DNews’ Trace Dominguez and Amy Shira Teitel. But this week, Science Presents DNews will welcome a special guest host: President Barack Obama.…