Delayed one day by unstable weather in Florida, the Discovery astronauts are preparing the shuttle for another landing try today, on one coast or the other, to close out a busy space station resupply mission.

The crew has two landing opportunities at the Kennedy Space Center in Florida, at 5:48 p.m. EDT and 7:23 p.m., followed by two at Edwards Air Force Base in California's Mojave Desert, at 8:53 p.m. and 10:28 p.m. All four opportunities come on successive orbits roughly 90 minutes apart.

The astronauts were awakened at 9:30 a.m. by a recording of Aaron Tippin's "Big Boy Toys" radioed up for commander Frederick "C.J." Sturckow.

"Good morning, Houston," Sturckow called down. "It's another great day in space and we hope the weather works out and we can get to land the space shuttle Discovery today."

Two attempts to land in Florida on Thursday were waved off due to showers and thunderstorms within 30 nautical miles of the Kennedy Space Center runway. The Spaceflight Meteorology Group at the Johnson Space Center in Houston is predicting more of the same, if not worse, today with scattered clouds at 3,000 and 8,000 feet, a broken deck at 25,000 feet, winds from 130 degrees gusting to 12 knots and thunderstorms within the no-rain zone.

The forecast for the first opportunity at Edwards calls for ideal conditions with scattered clouds at 10,000 feet, a broken deck at 25,000 feet and winds out 210 degrees with gusts to 12 knots. The wind changes to 240 degrees with gusts to 18 knots for the second opportunity, but that is still within limits.

If those forecasts hold up, entry Flight Director Richard Jones may wave off the first Florida opportunity early, set up for the second and if that doesn't work out, divert the crew to Edwards.

Discovery has enough on-board supplies to remain in orbit through Sunday, but NASA does not schedule landings on the final day in case of a technical problem or bad weather. In this case, Saturday is the last available day for a planned landing and Jones initially said he would keep the crew up as long as there was a reasonable chance to get Discovery back to Florida.

But given the current forecast, with more bad weather expected near the Kennedy Space Center on Saturday, Jones is expected to bring Discovery down today, at Kennedy or Edwards.

Here are detailed timelines for all four landing opportunities (in EDT; best viewed with fixed-width font):

Rev. 217 Deorbit to Kennedy Space Center (KSC)

Deorbit burn: 04:41:37 PM
Change in velocity: 187 mph
Burn duration: 02:42
Crossrange: 581 sm
Range to KSC from EI: 5,048 sm
Turn: 230-degree left
Runway: 15
Landing: 05:48:57 PM
EOM miles flown: 5.7 million

EDT...........EVENT

12:41 PM......Begin deorbit timeline
12:56 PM......Radiator stow
01:06 PM......Mission specialists seat installation
01:12 PM......Computers set for deorbit prep
01:16 PM......Hydraulic system configuration
01:41 PM......Flash evaporator checkout
01:47 PM......Final payload deactivation
02:01 PM......Payload bay doors closed
02:11 PM......Mission control 'go' for OPS-3
02:21 PM......OPS-3 transition
02:46 PM......Entry switchlist verification
02:56 PM......Deorbit PAD update
03:01 PM......Crew entry review
03:16 PM......CDR/PLT don entry suits
03:33 PM......IMU alignment
03:41 PM......CDR/PLT strap in; MS suit don
03:58 PM......Shuttle steering check
04:01 PM......Hydraulic system prestart
04:08 PM......Toilet deactivation
04:21 PM......MCC 'go' for deorbit burn
04:27 PM......MS seat ingress
04:36 PM......Single APU start

04:41:37 PM...Deorbit ignition
04:44:19 PM...Deorbit burn complete

05:17:19 PM...Entry interface
05:22:21 PM...1st roll command to left
05:34:48 PM...1st roll left to right
05:35:57 PM...C-band radar acquisition
05:42:34 PM...Velocity less than mach 2.5
05:44:44 PM...Velocity less than mach 1
05:45:37 PM...230-degree left turn to runway 15
05:48:57 PM...Landing

-----------------------

Rev. 218 Deorbit to KSC

Deorbit burn: 06:17:37 PM
Change in velocity: 182 mph
Burn duration: 2:38
Crossrange: 399 sm
Range to KSC from EI: 5,072 sm
Turn: 265-degree left turn
Runway: 15
Landing: 07:23:36 PM
EOM miles flown: 5.7 million

EDT...........EVENT

05:57 PM......MCC 'go' for deorbit burn
06:03 PM......MS seat ingress
06:12 PM......Single APU start

06:17:37 PM...Deorbit ignition
06:20:15 PM...Deorbit burn complete

06:51:55 PM...Entry interface
06:56:54 PM...1st roll command to right
07:08:04 PM...1st right-to-left roll reversal
07:10:36 PM...C-band radar acquisition
07:17:12 PM...Velocity less than mach 2.5
07:19:21 PM...Velocity less than mach 1
07:19:57 PM...265-degree left turn to runway 15
07:23:36 PM...Landing

-----------------------

Rev. 219 Deorbit to Edwards Air Force Base (EDW)

Deorbit burn: 07:47:37 PM
Change in velocity: 182 mph
Burn Duration: 2:38
Crossrange: 429 sm
Range to EDW from EI: 5,061 sm
Turn: 207-degree left turn
Runway: EDW 22
Landing: 08:53:34 PM
EOM miles flown: 5.8 million

EDT...........EVENT

07:27 PM......MCC 'go' for deorbit burn
07:33 PM......MS seat ingress
07:42 PM......Single APU start

07:47:37 PM...Deorbit ignition
07:50:15 PM...Deorbit burn complete

08:22:03 PM...Entry interface
08:27:03 PM...1st roll command to left
08:38:09 PM...1st left-to-right roll reversal
08:40:34 PM...C-band radar acquisition
08:47:18 PM...Velocity less than mach 2.5
08:49:30 PM...Velocity less than mach 1
08:50:25 PM...207 degree left turn to runway 15
08:53:34 PM...Landing

-----------------------

Rev. 220 Deorbit to EDW

Deorbit burn: 09:23:37 PM
Change in velocity: 183 mph
Burn Duration: 2:39
Crossrange: 452 sm
Range to EDW from EI: 5,038 sm
Turn: 185-degree left turn
Runway: EDW 22
Landing: 10:28:21 PM
EOM miles flown: 5.8 million

EDT...........EVENT

09:03 PM......MCC 'go' for deorbit burn
09:09 PM......MS seat ingress
09:18 PM......Single APU start

09:23:37 PM...Deorbit ignition
09:26:16 PM...Deorbit burn complete

09:56:56 PM...Entry interface
10:01:53 PM...1st roll command to right
10:12:59 PM...1st right-to-left roll reversal
10:15:21 PM...C-band radar acquisition
10:22:07 PM...Velocity less than mach 2.5
10:24:19 PM...Velocity less than mach 1
10:25:24 PM...185-degree left turn to runway 22
10:28:21 PM...Landing

Additional coverage for subscribers:
VIDEO: WEATHER POSTPONES LANDING A DAY PLAY
VIDEO: FIRST LANDING OPPORTUNITY WAVED OFF PLAY

VIDEO: FLIGHT DAY 13 HIGHLIGHTS MOVIE PLAY
VIDEO: PREVIEW OF DISCOVERY'S RE-ENTRY EXPERIMENT PLAY
VIDEO: PRE-LANDING BRIEFING WITH ENTRY FLIGHT DIRECTOR PLAY
VIDEO: CREW INTERVIEWS WITH CBS, ABC AND CNN PLAY
VIDEO: ASTRONAUTS' HOME MOVIES: DAY 12 PLAY
VIDEO: ASTRONAUTS' HOME MOVIES: DAY 11 PLAY
VIDEO: ASTRONAUTS' HOME MOVIES: DAY 10-P2 PLAY

VIDEO: FLIGHT DAY 12 HIGHLIGHTS MOVIE PLAY
VIDEO: TUESDAY EVENING'S MISSION STATUS BRIEFING PLAY
VIDEO: DISCOVERY FLIES AROUND INTERNATIONAL SPACE STATION PLAY
VIDEO: SHUTTLE DISCOVERY UNDOCKS FROM SPACE STATION PLAY
VIDEO: TUESDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY

VIDEO: FLIGHT DAY 11 HIGHLIGHTS MOVIE PLAY
VIDEO: MONDAY EVENING'S MISSION STATUS BRIEFING PLAY
VIDEO: FAREWELL BETWEEN SHUTTLE AND STATION CREWS PLAY
VIDEO: LEONARDO MODULE RETURNED TO THE PAYLOAD BAY PLAY
VIDEO: ASTRONAUTS ANSWER QUESTIONS SUBMITTED BY PUBLIC PLAY
VIDEO: TELEMUNDO, TAMPA AND UNIVISION CREW INTERVIEWS PLAY
VIDEO: EL PASO AND AUSTIN TELEVISION CREW INTERVIEWS PLAY
VIDEO: JOSE HERNANDEZ LIVE INTERVIEWS FROM ORBIT PLAY
VIDEO: MONDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY

VIDEO: FLIGHT DAY 10 HIGHLIGHTS MOVIE PLAY
VIDEO: EUROPEAN SPACE AGENCY ASTRONAUT EVENT PLAY
VIDEO: ASTRONAUTS' HOME MOVIES: DAY 10 PLAY
VIDEO: ASTRONAUTS' HOME MOVIES: DAY 9 PLAY
VIDEO: SUNDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY

VIDEO: POST-EVA MISSION STATUS BRIEFING PLAY
VIDEO: FLIGHT DAY 9 HIGHLIGHTS MOVIE PLAY
VIDEO: FUGLESANG'S HELMET-CAM COMES LOOSE PLAY
VIDEO: ROUTING AVONICS CABLES FOR TRANQUILITY PLAY
VIDEO: FAILED ORIENTATION SENSOR REMOVED PLAY
VIDEO: WORK TO DEPLOY PAYLOAD MECHANISM PLAY
VIDEO: EVA NO. 3 BEGINS PLAY
VIDEO: SATURDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY

VIDEO: ASTRONAUTS' HOME MOVIES: DAY 8 PLAY
VIDEO: INTERNATIONAL CREW NEWS CONFERENCE PLAY
VIDEO: FLIGHT DAY 8 HIGHLIGHTS MOVIE PLAY
VIDEO: FRIDAY AFTERNOON'S MISSION STATUS BRIEFING PLAY
VIDEO: FRIDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY

HIGH DEFINITION TV DAY 7: SPACEWALKERS COME BACK INSIDE PLAY
HIGH DEFINITION TV DAY 7: MORE WORK WITH LEONARDO PLAY
HIGH DEFINITION TV DAY 7: OLIVAS AND FUGLESANG ON EVA PLAY

VIDEO: FLIGHT DAY 7 HIGHLIGHTS MOVIE PLAY
VIDEO: ASTRONAUTS' HOME MOVIES: DAY 7 PLAY
VIDEO: POST-EVA MISSION STATUS BRIEFING PLAY
VIDEO: OLD TANK MOVED TO SHUTTLE FOR RECYCLING PLAY
VIDEO: NEW TANK HOOKED UP TO STATION UMBILICALS PLAY
VIDEO: CHRISTER FUGLESANG CARRIES NEW AMMONIA TANK PLAY
VIDEO: PREPS IN SHUTTLE BAY TO UNPACK NEW AMMONIA TANK PLAY
VIDEO: DANNY OLIVAS FLOATS OUT OF AIRLOCK TO START EVA PLAY
VIDEO: THURSDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY
VIDEO: STEP-BY-STEP SUMMARY OF SPACEWALK NO. 2 PLAY

HIGH DEFINITION TV DAY 6: PREPPING FOR NEXT EVA PLAY
HIGH DEFINITION TV DAY 6: MOVING FROZEN SCIENCE PLAY
HIGH DEFINITION TV DAY 6: EMPTYING OUT LEONARDO PLAY

HIGH DEFINITION TV DAY 5: SPACEWALKERS CELEBRATE PLAY
HIGH DEFINITION TV DAY 5: OLIVAS AND STOTT ON EVA NO. 1 PLAY
HIGH DEFINITION TV DAY 5: COLBERT TREADMILL UNPACKED PLAY
HIGH DEFINITION TV DAY 5: SPACEWALKERS GET SUITED UP PLAY

HIGH DEFINITION TV DAY 4: LEONARDO MODULE OPENED PLAY
HIGH DEFINITION TV DAY 4: MOVING ITEMS FROM SHUTTLE PLAY

VIDEO: FLIGHT DAY 6 HIGHLIGHTS MOVIE PLAY
VIDEO: ASTRONAUTS' HOME MOVIES: DAY 6 PLAY
VIDEO: WEDNESDAY NIGHT'S MISSION STATUS BRIEFING PLAY
VIDEO: WEDNESDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY

VIDEO: FLIGHT DAY 5 HIGHLIGHTS MOVIE PLAY
VIDEO: POST-EVA MISSION STATUS BRIEFING PLAY
VIDEO: SPACEWALKERS PUT THIRD EXPERIMENT IN SHUTTLE PLAY
VIDEO: BRIEFCASE-LIKE PACKAGE RETRIEVED FROM STATION PLAY
VIDEO: EUROPEAN PAYLOAD MOVED FROM STATION TO SHUTTLE PLAY
VIDEO: SPACEWALKERS FREE COOLANT TANK FROM TRUSS PLAY
VIDEO: DANNY OLIVAS DISCONNECTS OLD AMMONIA TANK PLAY
VIDEO: ASTRONAUTS EMERGE FROM AIRLOCK TO START EVA PLAY
VIDEO: OVERVIEW OF FLIGHT DAY 5 ACTIVITIES PLAY
VIDEO: STEP-BY-STEP SUMMARY OF SPACEWALK NO. 1 PLAY
VIDEO: TUESDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY

VIDEO: FLIGHT DAY 4 HIGHLIGHTS MOVIE PLAY
VIDEO: MONDAY NIGHT'S MISSION STATUS BRIEFING PLAY
VIDEO: NARRATED OVERVIEW OF THE LEONARDO PAYLOAD PLAY
VIDEO: ASTRONAUTS OPEN UP AND ENTER LEONARDO MODULE PLAY
VIDEO: TIME-LAPSE OF LEONARDO MODULE'S INSTALLATION PLAY
VIDEO: LEONARDO CARGO MODULE ATTACHED TO STATION PLAY
VIDEO: MONDAY'S MISSION MANAGEMENT TEAM UPDATE PLAY
VIDEO: MONDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY

HIGH DEFINITION TV DAY 3: NICOLE STOTT ABOARD STATION PLAY
HIGH DEFINITION TV DAY 3: UNITING STATION AND SHUTTLE PLAY
HIGH DEFINITION TV DAY 3: JOIN THE CREW DURING DOCKING PLAY
HIGH DEFINITION TV DAY 3: LIFE ON RENDEZVOUS DAY PLAY

VIDEO: FLIGHT DAY 3 HIGHLIGHTS MOVIE PLAY
VIDEO: SUNDAY NIGHT'S MISSION STATUS BRIEFING PLAY
VIDEO: SHUTTLE CREW WELCOMED ABOARD STATION PLAY
VIDEO: DOCKING RING RETRACTED TO JOIN TWO CRAFT PLAY
VIDEO: TIME-LAPSE OF DOCKING FROM CENTERLINE PLAY
VIDEO: SHUTTLE FLIES OUT IN FRONT OF STATION PLAY
VIDEO: DISCOVERY PERFORMS 360-DEGREE BACKFLIP PLAY
VIDEO: BEAUTIFUL VIEWS OF DISCOVERY APPROACHING PLAY
VIDEO: TIME-LAPSE VIEW FROM SHUTTLE DOCKING PORT PLAY
VIDEO: STATION CAMERA CATCHES DISCOVERY'S "TI BURN" PLAY
VIDEO: SUNDAY'S MISSION MANAGEMENT TEAM UPDATE PLAY
VIDEO: NARRATED PREVIEW OF RENDEZVOUS AND DOCKING PLAY
VIDEO: THE MOON SINKS BELOW TAIL OF DISCOVERY PLAY
VIDEO: ASTRONAUTS' HOME MOVIES: DAY 2 PLAY
VIDEO: ASTRONAUTS' HOME MOVIES: DAY 1 PLAY

VIDEO: FLIGHT DAY 2 HIGHLIGHTS MOVIE PLAY
VIDEO: SATURDAY NIGHT'S MISSION STATUS BRIEFING PLAY
VIDEO: NARRATED PREVIEW OF SHUTTLE INSPECTIONS PLAY

VIDEO: LAUNCH REPLAY: INSIDE MISSION CONTROL ROOM PLAY
VIDEO: LAUNCH REPLAY: VAB ROOF PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: PRESS SITE PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: PAD PERIMETER PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: BEACH TRACKER PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: PAD CAEMRA 070 PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: PAD CAEMRA 071 PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: UCS-23 TRACKER PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: PLAYALINDA BEACH PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: PAD FRONT CAMERA PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: PATRICK AIR FORCE BASE PLAY | HI-DEF

VIDEO: POST-LAUNCH BRIEFING PLAY
VIDEO: FLIGHT DAY 1 HIGHLIGHTS MOVIE PLAY
VIDEO: THE FULL LAUNCH EXPERIENCE PLAY
VIDEO: LIFTOFF OF SPACE SHUTTLE DISCOVERY! PLAY | HI-DEF
VIDEO: COMMANDER RICK STURCKOW BOARDS DISCOVERY PLAY
VIDEO: PILOT KEVIN FORD BOARDS SHUTTLE DISCOVERY PLAY
VIDEO: MISSION SPECIALIST PAT FORRESTER BOARDS DISCOVERY PLAY
VIDEO: MISSION SPECIALIST JOSE HERNANDEZ BOARDS SHUTTLE PLAY
VIDEO: MISSION SPECIALIST DANNY OLIVAS BOARDS DISCOVERY PLAY
VIDEO: MISSION SPECIALIST CHRISTER FUGLESANG BOARDS PLAY
VIDEO: MISSION SPECIALIST NICOLE STOTT BOARDS DISCOVERY PLAY
VIDEO: ASTRONAUTS LEAVE CREW QUARTERS BUILDING PLAY | HI-DEF
VIDEO: CREW FINISHES GETTING SUITED UP PLAY | HI-DEF

VIDEO: NARRATED MISSION OVERVIEW MOVIE PLAY | HI-DEF
VIDEO: MEET SHUTTLE DISCOVERY'S ASTRONAUTS PLAY | HI-DEF
VIDEO: NARRATED REVIEW OF SHUTTLE'S PREPARATIONS PLAY | HI-DEF
VIDEO: NARRATED REVIEW OF PAYLOADS' PREPARATIONS PLAY | HI-DEF
VIDEO: THE "COLBERT" TREADMILL PLAY | HI-DEF

VIDEO: MANAGERS EXPLAIN REASON FOR SECOND SCRUB PLAY
VIDEO: WEATHER SCRUBS FIRST COUNTDOWN PLAY | HI-DEF
VIDEO: ASTRONAUTS DEPART QUARTERS FOR PAD 39A PLAY | HI-DEF
VIDEO: CREW GETS SUITED UP FOR LAUNCH ATTEMPT PLAY | HI-DEF
VIDEO: LAUNCH PAD SERVICE GANTRY ROLLED BACK PLAY | HI-DEF

VIDEO: PRE-LAUNCH INTERVIEW WITH RICK STURCKOW PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH KEVIN FORD PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH PAT FORRESTER PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH JOSE HERNANDEZ PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH DANNY OLIVAS PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH CHRISTER FUGLESANG PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH NICOLE STOTT PLAY

VIDEO: AMERICAN AND EUROPEAN PRE-LAUNCH NEWS CONFERENCE PLAY
VIDEO: THE LAUNCH COUNTDOWN GETS UNDERWAY PLAY
VIDEO: ASTRONAUTS ARRIVE AT THE CAPE FOR LAUNCH PLAY | HI-DEF
VIDEO: FLIGHT READINESS REVIEW SETS LAUNCH DATE PLAY

VIDEO: SHUTTLE AND STATION PROGRAM UPDATE PLAY
VIDEO: THE STS-128 MISSION OVERVIEW BRIEFING PLAY
VIDEO: PREVIEW BRIEFING ON MISSION'S SPACEWALKS PLAY
VIDEO: THE ASTRONAUTS' PRE-FLIGHT NEWS BRIEFING PLAY
VIDEO: SHUTTLE PROGRAM MANAGER EXPLAINS FOAM ISSUES PLAY

VIDEO: PAYLOAD BAY DOORS CLOSED FOR FLIGHT PLAY | HI-DEF
VIDEO: MISSION CARGO LOADED ABOARD DISCOVERY PLAY | HI-DEF

VIDEO: CREW TOURS PAD'S CLEANROOM PLAY | HI-DEF
VIDEO: SHUTTLE EVACUATION PRACTICE PLAY | HI-DEF
VIDEO: ASTRONAUTS BOARD DISCOVERY PLAY | HI-DEF
VIDEO: THE LAUNCH DAY SIMULATION BEGINS PLAY | HI-DEF
VIDEO: PAD BUNKER TRAINING FOR THE CREW PLAY | HI-DEF
VIDEO: CREW BRIEFED ON EMERGENCY PROCEDURES PLAY | HI-DEF
VIDEO: NIGHTTIME APPROACHES IN TRAINING AIRCRAFT PLAY | HI-DEF
VIDEO: TEST-DRIVING EMERGENCY ARMORED TANK PLAY | HI-DEF
VIDEO: INFORMAL CREW NEWS CONFERENCE AT LAUNCH PAD PLAY
VIDEO: ASTRONAUTS ARRIVE FOR PRACTICE COUNTDOWN PLAY

VIDEO: SHUTTLE DISCOVERY ROLLS OUT PAD 39A PLAY | HI-DEF
VIDEO: ORBITER HOISTED FOR MATING TO TANK PLAY | HI-DEF
VIDEO: DISCOVERY MOVED TO ASSEMBLY BUILDING PLAY | HI-DEF
VIDEO: TIME-LAPSE OF DISCOVERY ARRIVING IN VAB PLAY

VIDEO: PAYLOADS DELIVERED TO LAUNCH PAD PLAY | HI-DEF
VIDEO: LEONARDO PUT INTO TRANSPORTER PLAY | HI-DEF
VIDEO: STATION'S NEW AMMONIA TANK PLAY | HI-DEF
VIDEO: MPLM HATCH CLOSED FOR FLIGHT PLAY | HI-DEF
VIDEO: INSIDE SHUTTLE MAIN ENGINE SHOP PLAY | HI-DEF
VIDEO: CREW EQUIPMENT INTERFACE TEST PLAY | HI-DEF
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