NASA-TV will carry it - but beware that their "schedule" can change at any time. Check the link below for updates:
http://www.nasa.gov/multimedia/nasatv/MM_NTV_Breaking.html
From that page, this is the NASA-TV schedule as of 5/22/08:
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May
May 21, Wednesday
12:55 p.m. - ISS Expedition 17 In-Flight Interview with "This Week in Baseball" for Fox Sports – JSC (Public and Media Channels)
2 p.m. - Interviews with STS-124 Commander Mark E. Kelly and Mission Specialist Karen L. Nyberg - HQ (Public and Media Channels)
4 - 6 p.m. - Interviews with STS-124 Pilot Kenneth T. Ham, Mission Specialist Michael E. Fossum and JAXA astronaut, Mission Specialist Akihiko Hoshide - HQ (Public and Media Channels)
8 p.m. - Interview with STS-124 Mission Specialist Ronald J. Garan Jr - HQ - (Public and Media Channels)
May 22, Thursday
11 a.m. - NASA Aeronautics Technical Seminar -- Electron Beam Freeform Fabrication: A Fabrication Process that Revolutionizes Aircraft Structural Designs and Spacecraft Supportability - HQ (Education Channel)
12:50 p.m. - ISS Expedition 17 In-Flight Interview with the Discovery Home Network's "The G Word" Show - JSC (Public and Media Channels)
2:30 p.m. - Mars Phoenix Lander Briefing - Entry Descent and Landing Overview - JPL (Public and Media Channels)
4 p.m. - Interviews with STS-124 Commander Mark E. Kelly and Mission Specialist Karen L. Nyberg - HQ (Public and Media Channels)
7 - 9 p.m. - Interviews with STS-124 Pilot Kenneth T. Ham, Mission Specialist Michael E. Fossum and JAXA astronaut, Mission Specialist Akihiko Hoshide - HQ (Public and Media Channels)
10 p.m. - Interview with STS-124 Mission Specialist Ronald J. Garan Jr - HQ (Public and Media Channels)
May 23, Friday
6 - 10 a.m. - Mars Phoenix Lander Live Satellite Interviews with Dr. Michael Meyer - JPL (Media Channel)
May 24, Saturday
3 p.m. - Mars Phoenix Lander Briefing - Landing Preview - JPL (Public and Media Channels)
May 25, Sunday
3 p.m. - Mars Phoenix Lander Briefing - JPL (Public and Media Channels)
6 p.m. - Mars Phoenix Lander Landing Coverage - JPL (Media Channel)
6:30 - 8:45 p.m. - Mars Phoenix Lander Landing Coverage - JPL (Public Channel)
9:30 p.m. - Mars Phoenix Lander Briefing - First Downlink of Data - JPL (Public and Media Channels)
May 26, Monday
6 - 10 a.m. - Mars Phoenix Lander Live Satellite Interviews - JPL (Media Channel)
12 a.m. - Mars Phoenix Lander Post Landing Briefing - JPL (Public and Media Channels)
2 p.m. - Mars Phoenix Lander Update Briefing - JPL (Public and Media Channels)
May 28, Wednesday
6:30 a.m. - STS-124 B-Roll Feed - JSC (Public and Media Channels)
7 - 9 a.m. - Live Interviews with STS-124/1J Lead Space Station Flight Director Annette Hasbrook – JSC (Public and Media Channels)
10 a.m. - Countdown Status Briefing - KSC (Public and Media Channels)
10:30 a.m. - ISS Commentary - JSC (Public and Media Channels)
11:30 a.m. - STS-124 Crew Arrival - (Public and Media Channels)
May 29, Thursday
8 a.m. - Interviews with STS-124 Commander Mark E. Kelly and Mission Specialist Karen L. Nyberg - HQ (Public and Media Channels)
10 a.m. - ISS Commentary and Mission Coverage - JSC (Public and Media Channels)
11 a.m. - STS-124 Launch Readiness News Conference - KSC (Public and Media Channels)
1 p.m. - JAXA Kibo Briefing - KSC (Public and Media Channels)
2 p.m. - Mars Phoenix Lander Briefing - JPL from Tucson (Public and Media Channels)
4 - 6 p.m. - Interviews with STS-124 Pilot Kenneth T. Ham, Mission Specialist Michael E. Fossum and JAXA astronaut, Mission Specialist Akihiko Hoshide - HQ (Public and Media Channels)
May 30, Friday
9 a.m. - ISS Commentary and Mission Coverage - JSC (Public and Media Channels)
10 a.m. - Countdown Status Briefing - KSC (Public and Media Channels)
11 a.m. - ISS National Science Laboratory Briefing - KSC (Public and Media Channels)
12 p.m. - STS-124 Webcast - KSC (Public and Media Channels)
2 p.m. - Mars Phoenix Lander Update Briefing - JPL from Tucson (Public and Media Channels)
May 31, Saturday
12 p.m. - STS-124 Launch Coverage and Commentary (Launch is scheduled for 5:02 p.m.) - KSC/JSC (Public and Media Channels)
June
June 13, Friday
4 p.m. - OSTM Prelaunch News Conference - VAFB/KSC (Public and Media Channels)
5 p.m. - OSTM Mission Science Briefing - VAFB/KSC (Public and Media Channels)
June 15, Sunday
2:30 a.m. - OSTM Commentary and Launch Coverage (launch is scheduled for 4:47 a.m.) - VAFB/KSC (Public and Media Channels)
All times Eastern. Programs may be pre-empted without advance notice.
Matthew Ota said:
Read my preview story here:
http://sciencedude.freedomblogging.com/2008/05/14/matts-mars-landing-preview/