WHAT: A media opportunity in which Mike Brown, a California Institute of Technology astronomy professor, will be available to comment on the International Astronomical Union (IAU) vote on the definition of a planet.

The IAU, an international group of professional astronomers, will vote on one or more resolutions that will set the course for the future of planet naming. This vote was spurred by Brown’s finding of planet-like object 2003 UB313, aka Xena.

He and other faculty, including David Stevenson, a professor of planetary science, will watch the webcast of the vote and will comment on it.

WHEN: 5 to 10 a.m. PDT, Thursday, August 24. The actual vote(s) will be taken during the final IAU general assembly that will take place from 5 to 8:30 a.m. PDT in Prague, Czech Republic. The exact time of the vote is not known because this item is one of 19 on the agenda for that meeting, and it is listed in the middle of the meeting agenda. There will likely be no discussion on the matter in Prague, but rather a mere calling for the vote on one or more resolutions regarding what constitutes a planet and what doesn’t. There has been much debate on the resolution during the past few days in Prague.

WHERE: The Seismology Media Center in Caltech’s South Mudd Building at the northeast corner of Wilson and California in Pasadena. The room is on the second floor, room 269. Parking is available at the second driveway north of the South Mudd Building.

FOR MORE INFO: Contact Jill Perry, Caltech Media Relations, during normal office hours at 1-626-395-3226. On Thursday morning, call Jill at 1-626-688-0014.