After cosmologists account for ordinary matter and dark matter, what’s left is... dark energy, which appears to make up 72% of the universe. Astronomer Andy Howell, who collaborated with one of the winners of the 2011 Nobel Prize in physics, studies thermonuclear supernovae as a source of measurements of dark energy. Some of these are caused by “zombie stars,” white dwarf stars that suck matter from companion stars, roar back to life and explode. He’s helping to build a new global robotic network of telescopes to study supernovae and find extrasolar planets. By circumventing the weather and rising sun, it will enable months-long continuous observations for the first time. New results are expected this year from other measurements of dark energy, and if NASA can redeploy two spy satellites for science, those observations will help the hunt. “We’ll have two more Hubbles,” says Howell.

Attendees who register at the CASW website can download background material and the presentation at http://casw.org/astronomy/new-horizons-science-2012/briefs/dark-energy-z....