[image-50]NASA will host a media briefing at 2 p.m. EDT Thursday, Oct. 9, to outline the space and Earth-based assets that will have extraordinary opportunities to image and study a comet from relatively close range to Mars on Sunday, Oct. 19.

The briefing will be held in NASA Headquarters’ auditorium, 300 E Street SW in Washington, and broadcast live on NASA Television and the agency’s website.

Comet C/2013 A1 Siding Spring will miss Mars by only about 88,000 miles (139,500 kilometers). That is less than half the distance between Earth and its moon and less than one-tenth the distance of any known comet flyby of Earth. The comet's nucleus will come closest to Mars at about 2:27 p.m. EDT (11:27 a.m. PDT), hurtling at about 126,000 mph (56 kilometers per second), relative to Mars.

The concerted campaign of observations by multiple spacecraft at Mars and by numerous NASA assets is directed at the comet and its effect on the Martian atmosphere. The observations of the comet may yield fresh clues to our solar system's earliest days more than four billion years ago.

Panelists include:

Jim Green, director, Planetary Science Division (PSD), NASA Headquarters, Washington

Kelly Fast, program scientist, PSD

Carey Lisse, senior astrophysicist, Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland

Padma Yanamandra-Fisher, senior research scientist, Space Science Institute, Rancho Cucamonga Branch, California

Media can ask questions from participating NASA locations, or by telephone. To participate by phone reporters must contact Steve Cole at 202-358-0918 or stephen.e.cole@nasa.gov and provide their media affiliation by 1 p.m. Thursday. The public also may ask questions on social media using the hashtag #askNASA.

For more about the comet, visit:

http://mars.nasa.gov/comets/sidingspring

For NASA Television downlink information, scheduling information and streaming video, visit:

http://www.nasa.gov/nasatv

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