Opportunity will reach Mars on Jan. 25, 2004. Together the two MER missions, Spirit and Opportunity, seek to determine the history of climate and water at two sites on Mars where conditions may once have been favorable to life. Both rovers are identical. Each rover carries five scientific instruments including a panoramic camera and microscope, plus a rock abrasion tool that will grind away the outer surfaces of rocks to expose their interiors for examination. The rovers each weigh approximately 400 pounds. They will navigate themselves around obstacles as they drive across the Martian surface, traveling up to about 130 feet each Martian day. Each rover's prime mission is planned to last three months on Mars.

PRELAUNCH PRESS CONFERENCE

The prelaunch press conference is scheduled for L-2 days, Tuesday, June 24 at 1 p.m. EDT in the KSC News Center auditorium and will be carried live on NASA Television. Participating in the briefing will be:

Dr. Ed Weiler, Associate Administrator, Office of Space Science
NASA Headquarters

Omar Baez, NASA launch director
NASA John F. Kennedy Space Center

Kris Walsh, Boeing director for NASA programs
Boeing Expendable Launch Systems

Peter Theisinger, Mars Exploration Rover project manager
Jet Propulsion Laboratory

Dr. Joy Crisp, Mars Exploration Rover project scientist
Jet Propulsion Laboratory

Dr. Steve Squyers, Mars Exploration Rover principal investigator
Cornell University

Joel Tumbiolo, Launch Weather Officer
45th Weather Squadron, Cape Canaveral Air Force Station

No post-launch press conference will be held.

ACCREDITATION

Media not already accredited for the MER-B/Opportunity prelaunch press conference and launch day activities should send a letter of request to the NASA-KSC News Center on news organization letterhead. It should include full legal name, Social Security Number, birth date, birthplace and country of citizenship. Accreditation requests must be received by the close of business on Friday, June 20. Letters may be faxed to 321-867-2692 or addressed to:

MER-B Launch Accreditation NASA XA-E1 Kennedy Space Center, FL 32899

Badges may be obtained at Gate 3 on State Road 405, just east of U.S. 1 south of Titusville Monday through Friday between 6 a.m. and 5 p.m. Badges issued for MER-A are not valid. Badges to cover the MER-B launch from the Trident Bluff press viewing area will be available starting at 11 p.m. on June 25 and issued at the Pass and Identification Building on SR 401 outside Gate 1 of Cape Canaveral Air Force Station. Proof of identification and news media affiliation will be required.

Departure on launch day from the Gate 1 Pass and Identification Building for the Trident Bluff press viewing area will be at 11:15 p.m. After launch, media will be escorted back to Gate 1. An escort is required for all areas of the Kennedy Space Center and Cape Canaveral Air Force Station. For further information on MER-B launch accreditation, contact Diana Boles or Cynthia Pettiford at the NASA-KSC News Center at 321-867-2468.

L-1 DAY SET UP OF REMOTE CAMERAS

Media wishing to establish remote cameras at the launch pad should meet at the Gate 1 Pass and Identification Building of Cape Canaveral Air Force Station on State Road 401 on Wednesday, June 25, at 9:45 a.m. to be escorted to Space Launch Complex 17.

LAUNCH DAY PAD PHOTO OPPORTUNITY

A photo opportunity at Space Launch Complex 17 of the MER-B launch vehicle on the pad will be provided on the morning of launch day upon rollback of the mobile service tower. Media wishing to attend should be at the Gate 1 Pass and Identification Building of Cape Canaveral Air Force Station on SR 401 at 3:30 p.m.

PRESS SITE OPERATING HOURS

On June 25-26, the NASA News Center at KSC will be open from 8 a.m. - 4:30 p.m. and may be reached at 321-867-2468.

NASA TELEVISION COVERAGE, "V" CIRCUITS, AND LAUNCH STATUS

NASA Television will carry the prelaunch press conference beginning at 1 p.m. on Tuesday, June 24. A two-way question-and-answer capability will be available from other NASA field centers. No post-launch press conference is planned.

On launch day, Thursday, June 26, launch commentary will begin at 10:45 p.m. Coverage will conclude after acquisition of the spacecraft by the Deep Space Network no earlier than ninety minutes after launch, at which time the spacecraft's initial state of health will be reported.

NASA Television is available on satellite AMC-2, transponder 9C, located at 85 degrees West longitude.

Audio only of NASA Television coverage of the prelaunch news conference and launch commentary will be available on the "V" circuits which may be dialed directly at 321/867-1220, 867-1240, 867-1260, 867-7135.

The NASA-KSC News Center codaphone will carry recorded MER-B pre-launch status reports beginning at L-3 days, Monday, June 23, and may be dialed at 321-867-2525.

"NASA DIRECT!" WEB COVERAGE

The Kennedy Space Center's Expendable Launch Vehicle (ELV) coverage will include special webcasts on NASA Direct!

For more information on the MER-B/Opportunity web activities, go to http://www.ksc.nasa.gov/elvnew/merb/index.htm

For a detailed NASA Direct! event calendar, go to: http://www.ksc.nasa.gov/nasadirect/index.htm

Information about the MER missions is available on-line at: http://mars.jpl.nasa.gov/mer/