NASA will host a media teleconference with Hubble Space Telescope astronomers at 1 p.m. EST Thursday, Nov. 16, to announce the discovery that dark energy has been an ever-present constituent of space for most of the universe’s history.

Reporters must call Ray Villard at the Space Telescope Science Institute Press Office, Baltimore, at: 410-338-4514 (villard@stsci.edu) or Cheryl Gundy at 410-338-4707 (gundy@stsci.edu) for participation information. Images and graphics about the research will be posted shortly before the start of the briefing at:

http://www.nasa.gov/hubble

Briefing participants:

— Adam Riess, astrophysicist, Space Telescope Science Institute and Johns Hopkins University, Baltimore

— Mario Livio, senior astrophysicist, Space Telescope Science Institute

— Louis-Gregory Strolger, astronomer, Western Kentucky University, Bowling Green, Ky.

— Sean Carroll, senior research associate, California Institute of Technology, Pasadena, Calif.

Audio of the event will be available on the Internet at:

http://www.nasa.gov/newsaudio

For NASA TV streaming video, schedule and downlink information, visit:

http://www.nasa.gov/ntv