NASA will hold a media teleconference 1 p.m. EDT Tuesday, April 18, to announce a breakthrough in simulating black hole mergers and predicting their gravitational wave signatures. The finding is based on the largest astrophysical calculation ever performed by a NASA supercomputer.

To participate reporters should call: 1-800-369-3196 or: 210-234-0005, passcode “NASA.” Images and graphics supporting the briefing will be posted at the start of the event at:

Audio of the event will be streamed live at:

Briefing participants:

– Joan Centrella, chief, Gravitational Astrophysics Laboratory, NASA Goddard Space Flight Center, Greenbelt, Md.

– Peter Saulson, Syracuse University; Laser Interferometer Gravitational Wave Observatory Scientific Collaboration

– Larry Smarr, University of California, San Diego; director, California Institute for Telecommunications and Information Technology

A video file about the discovery will air on NASA TV on April 18. NASA TV is carried on an MPEG-2 digital signal accessed via satellite AMC-6, at 72 degrees west longitude, transponder 17C, 4040 MHz, vertical polarization. It’s available in Alaska and Hawaii on AMC-7 at 137 degrees west longitude, transponder 18C, at 4060 MHz, horizontal polarization. More information and streaming video links are available at: