Jump to the most recent addition.

NASA officials continue to plan to launch shuttle Endeavour to the International Space Station on Thursday.

KSC workers today were testing repairs done in Endeavour's rear engine compartment this weekend. There remains a chance the tests will show a plumbing-related problem will need further work, which could delay the launch. But things appeared to be going well as of this writing.

For now, the countdown is scheduled to begin about 11 p.m. EDT tonight and lead to a liftoff between 4 and 8 p.m. EDT Thursday. The exact launch time will be announced the day before.

NASA has officially confirmed that the countdown to Thursday's planned launch began at 11 p.m. EDT Sunday. Liftoff remains set for some time between 4 and 8 p.m. EDT Thursday.

Also, the seven-member flight team made up of the STS-111 and Expedition Five crews arrived at the Kennedy Space Center about midday Sunday.

Technically everything looks good so far. Repairs to a leaking valve inside Endeavour's rear engine compartment are complete and tested fine, said NASA Test Director Steve Altemus.

Weather is a concern, as usual.

Shuttle Weather Officer Kathy Winters said there is a 40 percent chance of acceptable conditions on Thursday, and only a 30 percent chance of good weather on Friday and Saturday.

The problem will be Florida's typical afternoon thunderstorms that start kicking in this time of year.

Altemus reported that NASA will make launch attempts Thursday and Friday, then stand down for two days and try again Monday and Tuesday.

Final preparations are under way for Thursday's scheduled launch of shuttle Endeavour to the International Space Station. Florida's dynamic weather, however, may spoil the show.

Launch weather officer Kathy Winters is predicting only a 40 percent chance of acceptable weather for the late Thursday afternoon launch attempt. Thunderstorms and anvil clouds are the concern - typical early evening weather conditions along the Space Coast in late May.

If the launch is delayed for any reason, weather conditions are expected to deteriorate over the weekend, with only a 30 percent probability of acceptable weather forecast for Friday and Saturday.

NASA officially confirmed that the countdown to Thursday's planned launch began at 11 p.m. EDT Sunday. Liftoff remains set for some time between 4 and 8 p.m. EDT Thursday. The exact launch window will be announced later today - 24 hours prior to launch.

NASA has officially announced the window for Thursday's launch attempt of shuttle Endeavour. The preferred liftoff time will be 7:44:26 p.m. EDT, during a launch window extending from 7:39:27 p.m. to 7:49:25 p.m. EDT.

Final preparations are being rushed to completion for Endeavour's 12-day mission to the International Space Station; Florida's dynamic weather, however, still threatens to spoil the show.

Launch weather officer Kathy Winters is predicting only a 40 percent chance of acceptable weather for Thursday's launch attempt. Thunderstorms and anvil clouds are the major concern - typical early evening weather conditions along the Space Coast in late May.

If the launch is delayed for any reason, weather conditions are expected to deteriorate over the weekend, with only a 30 percent probability of acceptable weather forecast for Friday and Saturday.

The countdown is proceeding smoothly toward this evening's launch of shuttle Endeavour on a mission to the International Space Station, but late-day thunderstorms are threatening to spoil the show.

Launch is now scheduled for 7:44:26 p.m. EDT during a launch window that extends from 7:39:27 to 7:49:25 p.m. EDT - a final adjustment of the launch time will be made at the T-9 minute hold to more precisely align with the space station's orbit.

Tanking operations, or the filling of Endeavour's massive external tank with a half-million gallons of liquid hydrogen and liquid oxygen, will commence at about 10:19 a.m. EDT. Meanwhile, there are no technical problems reported at pad 39A.

Weather continues to be the major concern with only a 40 percent probability of acceptable conditions forecast at launch time. Thunderstorms and anvil clouds in proximity to the shuttle and its flight path are the primary threats.

Tanking operations, or the filling of shuttle Endeavour's massive external tank with a half-million gallons of liquid hydrogen and liquid oxygen, is now under way. This three-hour procedure started at 10:32 a.m. EDT.

Meanwhile, there are no technical problems being worked at pad 39 as the countdown is proceeding smoothly toward this evening's launch of Endeavour. The launch team, however, will be closely monitoring weather conditions along Florida's Space Coast as late-day thunderstorms threaten to delay Endeavour's launch.

Launch is scheduled for 7:44:26 p.m. EDT during a launch window that closes about five minutes later at 7:49:25 p.m. EDT - a final adjustment of the launch time will be made at the T-9 minute hold to more precisely align with the space station's orbit.

Weather continues to be the major concern with only a 40 percent probability of acceptable conditions forecast at launch time. Thunderstorms and anvil clouds in proximity to the shuttle and its flight path are the primary threats.

Shuttle Endeavour's external tank is now filled with a half-million gallons of super-chilled liquid hydrogen and liquid oxygen in preparation for this evening's launch attempt. Fueling, or "tanking," operations started at 10:32 a.m. and just concluded at 1:26 p.m. EDT. The vehicle is now in "stable replenish" mode and its massive fuel tank will continue to be topped-off until launch time.

No technical problems are being reported at pad 39A as the countdown clock continues to tick down for this evening's launch attempt. The launch team, however, is closely monitoring weather conditions along Florida's Space Coast as late-day thunderstorms threaten to delay Endeavour's launch.

Launch is scheduled for 7:44:26 p.m. EDT during a launch window that closes about five minutes later at 7:49:25 p.m. EDT - a final adjustment of the launch time will be made at the T-9 minute hold to more precisely align with the space station's orbit.

Large puffy clouds are building to the west of the Kennedy Space Center and weather radar is starting to pick up a line of showers to the northwest of Orlando. Weather continues to be the major concern with only a 40 percent probability of acceptable conditions forecast at launch time. Thunderstorms and anvil clouds in proximity to the shuttle and its flight path are the primary threats.

NASA launch commentary has just started and video is being broadcast of the seven astronauts entering Endeavour in preparation for launch.

Shuttle Endeavour's external tank is filled with a half-million gallons of super-chilled liquid hydrogen and liquid oxygen for this evening's launch attempt. Fueling, or "tanking," operations started at 10:32 a.m. and were completed at 1:26 p.m. EDT. The vehicle is now in "stable replenish" mode and its massive fuel tank will continue to be topped-off until launch time.

No significant technical problems are being reported at pad 39A as the countdown clock continues to tick down for this evening's launch attempt. The launch team continues to closely monitor weather conditions along Florida's Space Coast.

The afternoon sea breezes from the east and west coasts of Florida are colliding over the center of the state, firing up late-day thunderstorms that are threatening to delay Endeavour's launch - only a 40 percent probability of acceptable conditions is forecast for launch time. Thunderstorms and anvil clouds in proximity to the shuttle and its flight path are the primary threats.

Launch is scheduled for 7:44:26 p.m. EDT during a launch window that closes about five minutes later at 7:49:25 p.m. EDT - a final adjustment of the launch time will be made at the T-9 minute hold to more precisely align with the space station's orbit.

The countdown for tonight's launch attempt of shuttle Endeavour on a mission to the International Space Station is at the T-20 minute hold - this is a planned built-in hold.

A possible malfunctioning regulator on the left hand Orbital Maneuvering System Engine is being investigated as the final preparations for this evening's launch attempt are being completed.

Launch remains scheduled for 7:44:26 p.m. EDT during a launch window that closes about five minutes later at 7:49:25 p.m. EDT; however, several bands of thunderstorms and anvil clouds have approached to within about 30 miles of the space center and may force a postponement of tonight's launch attempt. A crosswind condition has also developed at the Shuttle Landing Facility, further complicating the weather situation.

The seven member crew, led by veteran commander Ken Cockrell and Franklin Chang-Diaz who is making his record-tying 7th space mission, are positioned inside the Orbiter awaiting a Go/No-Go decision on the weather and their launch attempt. Endeavour is also transporting three members of the ISS Expedition 5 crew, led by Russian cosmonaut Valery Korzun, who will replace the Expedition Four crew now onboard the station.

The Shuttle Training Aircraft, flown by astronaut Charlie Precourt, is keeping a close eye on the weather conditions and reporting his findings to launch managers. A pair of Air Force F-15 fighter jets have been observed patrolling the skies over the Kennedy Space Center.

Thunderstorms and thick clouds converging on the Kennedy Space Center have forced NASA to scrub tonight's launch attempt of shuttle Endeavour due to the potential for triggered lightning and impaired visibility during an emergency abort landing.

A transient contamination was determined to be the cause of the erratic readings from the regulator on the left hand Orbital Maneuvering System Engine and would not have prevented a launch attempt.

The launch team is working toward a 24-hour scrub turnaround. A launch attempt on Friday will be about 22 minutes earlier than today's time at 7:22 p.m. EDT.

After thunderstorms and thick clouds forced NASA to scrub Thursday's launch of shuttle Endeavour, the launch team is working to recycle the vehicle for another attempt on Friday evening. Liftoff is scheduled for about 7:22 p.m. EDT.

Weather again will be a major concern as thunderstorms are forecast for Friday's launch window with only a 30 percent probability of acceptable conditions. A final decision whether to attempt a launch on Friday will be made by mission managers during a morning meeting prior to the start of fueling or "tanking" operations.

Transient contamination was determined to be the cause of erratic readings from an Orbital Maneuvering System Engine regulator discovered late in Thursday's countdown and will not be a factor in scheduling the next launch attempt.

Launch managers have decided to postpone another attempt to launch shuttle Endeavour this evening due to an unfavorable weather forecast that called for only a 20 percent probability of acceptable conditions.

Mission managers will meet at 7:30 p.m. EDT tonight to determine if a tanking meeting will be held on Saturday morning in preparation for another next launch attempt for Endeavour. Weather conditions are not expected to be favorable over the weekend, with only a 30 percent chance of acceptable conditions forecast for Saturday and Sunday.

After reviewing unfavorable weather forecasts for the next two days, NASA managers have decided to wait until Monday, June 3 as the next opportunity to launch shuttle Endeavour on a space station crew exchange mission.

The launch period for a Monday attempt will be 4 p.m. to 8 p.m. EDT - NASA will not release the exact launch time until 24 hours prior to launch.

NASA managers have delayed the next launch attempt of Endeavour to Tuesday, June 4 after deciding to replace a gaseous nitrogen pressure regulator in the shuttle's left Orbital Maneuvering System engine pod.

This is the same component that caused concern during the late stages of Thursday's scrubbed launch attempt but, at that time, engineers believed the problem to be caused by transient contamination. The regulator is now leaking again and mission managers have ordered it to be removed and replaced, delaying the next possible launch attempt to Tuesday.

Initial long-range weather forecasts indicated only a 30 percent chance of acceptable weather conditions during Tuesday's launch window; however, current trends suggest a slightly more optimistic weather outlook.

The launch period for a Tuesday attempt will be 4 p.m. to 8 p.m. EDT - NASA will not release the exact launch time until 24 hours prior to launch.

NASA managers met this morning to evaluate the progress of efforts to swap out a gaseous nitrogen pressure regulator in shuttle Endeavour's left Orbital Maneuvering System engine pod and decided to delay the next launch attempt to Wednesday, June 5, between 4 and 8 p.m. EDT. An exact launch time will be announced at 5 p.m. EDT Tuesday.

This is the same component that caused concern during the late stages of last Thursday's scrubbed launch attempt but, at that time, engineers believed the problem to be caused by transient contamination. Over the weekend, the valve showed signs of leaking again and mission managers ordered it to be removed and replaced.

According to NASA, Endeavour's launch attempt was delayed again until June 5 because of "the uniqueness of the change out and the work to build a test fixture required."

The long-range weather forecast for Wednesday shows some improvement but still indicates the chance of afternoon and evening thunderstorms and rain showers during the late-day launch period.

Technicians working at pad 39A have swapped out a faulty gaseous nitrogen regulator valve in shuttle Endeavour's left Orbital Maneuvering System pod. Leak checks on the replaced valve are in progress and, if successful, Endeavour will be targeted toward another launch attempt on Wednesday, June 5, between 4 and 8 p.m. EDT. NASA will announce an exact launch time at 5 p.m. EDT Tuesday.

This is the same component that caused concern during the late stages of last Thursday's scrubbed launch attempt. Over the weekend, technicians again detected a problem with the valve and mission managers ordered it to be removed and replaced, further delaying the next launch attempt to Wednesday.

This evening, launch crews are scheduled to top off the liquid hydrogen and liquid oxygen supplies in Endeavour's Power Reactant Storage and Distribution (PRSD) System.

Launch weather officer Kathy Winters has issued a slightly more optimistic forecast for Wednesday's launch period with a 60 percent probability of acceptable conditions. Afternoon thunderstorms and rain showers remain a concern, particularly the threat from anvil clouds generated by inland thunderstorms.

Replacement of a faulty valve in the shuttle's Orbital Maneuvering System has been completed, but unpredictable Florida weather is again threatening to spoil Endeavour's planned Wednesday launch attempt. Liftoff is scheduled between 4 and 8 p.m. EDT - NASA will announce the exact launch time at 5 p.m. EDT today.

Launch weather officer Kathy Winters has downgraded the forecast for Wednesday and is now predicting only a 40 percent chance of acceptable weather conditions. A combination of anvil clouds from inland thunderstorms, a thick cloud layer over the launch pad and stiff crosswinds at the shuttle landing facility may conspire to force another launch scrub. In addition, weather at the three overseas emergency landing strips is also of concern.

NASA test director Steve Altemus and his team are preparing for launch attempts on three of the next four days, in whatever combination provides the best chance to achieve a successful launch. Weather on Thursday will improve slightly with a 60 percent chance of good conditions, but deteriorate on Friday as thunderstorms will again lower the chances of acceptable conditions to only 40 percent.

Technicians working at pad 39A are topping off the liquid hydrogen and liquid oxygen supplies in Endeavour's Power Reactant Storage and Distribution (PRSD) System to support tomorrow's late afternoon launch attempt, although a power outage has put them about four hours behind schedule in their preparations.

NASA has officially announced the window for Wednesday's launch attempt of shuttle Endeavour on a 12-day mission to the International Space Station, but unpredictable Florida weather is again threatening to spoil the show.

Wednesday's preferred liftoff time will be 5:22:48 p.m. EDT, during a launch window extending from 5:17:49 p.m. to 5:27:47 p.m. EDT.

Launch weather officer Kathy Winters downgraded the forecast for Wednesday to only a 40 percent chance of acceptable weather conditions during the launch window. Anvil clouds from inland thunderstorms, rain showers, a thick cloud layer over the launch pad and stiff crosswinds at the shuttle landing facility may conspire to force another launch scrub. In addition, weather at the three overseas emergency landing strips is also of concern.

Testing of a replacement valve in the shuttle's Orbital Maneuvering System has been completed and technicians working at pad 39A have topped off the liquid hydrogen and liquid oxygen supplies in Endeavour's Power Reactant Storage and Distribution (PRSD) System, although a brief power outage put them about four hours behind schedule in their launch preparations.

NASA is preparing to support launch attempts on three of the next four days, in whatever combination provides the best chance for success. Thursday's weather forecast shows a slight improvement with a 60 percent chance of favorable conditions, but conditions again deteriorate on Friday as expected thunderstorms lower the probability of acceptable conditions to only 40 percent.

A seven-person crew has been dispatched to pad 39A to investigate an alarm on a panel in the Pad Terminal Connection Room, located beneath the launch pad. As a result, fueling or "tanking" of shuttle Endeavour's external tank with 500,000 gallons of liquid hydrogen and liquid oxygen, scheduled for about 8 a.m. EDT, has been delayed.

The window for today's launch attempt of Endeavour on a 12-day mission to the International Space Station extends from 5:17:49 p.m. to 5:27:47 p.m. EDT, with a preferred liftoff time of 5:22:48 p.m. EDT.

Weather is not looking promising. Thick clouds are expected to develop over Florida's Space Coast accompanied by stiff crosswinds that may exceed limits at the Shuttle Landing Facility. The official weather forecast calls for only a 40 percent probability of acceptable conditions at launch time.

Tanking operations, or the filling of shuttle Endeavour's massive external tank with a half-million gallons of liquid hydrogen and liquid oxygen, is now under way. This three-hour procedure started at 8:41 a.m. EDT - about 40 minutes late after technicians were dispatched to pad 39A to investigate a fire alarm on a panel in the Pad Terminal Connection Room, located beneath the launch pad.

Otherwise, there are no technical problems being reported as the countdown is proceeding smoothly toward this afternoon's launch of Endeavour on a 12-day space station crew exchange mission. The launch team will again be closely monitoring weather conditions along Florida's Space Coast as clouds and crosswinds threaten to delay Endeavour's launch.

The window for today's launch attempt of Endeavour extends from 5:17:49 p.m. to 5:27:47 p.m. EDT, with a preferred liftoff time of 5:22:48 p.m. EDT.

Weather is not looking promising. Thick clouds are expected to develop over Florida's Space Coast accompanied by stiff crosswinds that may exceed limits at the Shuttle Landing Facility. The official weather forecast calls for only a 40 percent probability of acceptable conditions at launch time.

Shuttle Endeavour's external tank is now filled with a half-million gallons of super-chilled liquid hydrogen and liquid oxygen in preparation for this evening's launch attempt. Fueling, or "tanking," operations started at 8:41 a.m. EDT - about 40 minutes late - and just concluded at 11:32 a.m. EDT. The vehicle is now in "stable replenish" mode and its massive fuel tank will continue to be topped-off until launch time.

No technical problems are being reported at pad 39A as the countdown clock continues to tick down for this afternoon's launch attempt. The launch team, however, is closely monitoring weather conditions along Florida's Space Coast as clouds and crosswinds threaten to again delay Endeavour's launch on a 12-day space station crew exchange mission.

Launch is scheduled for 5:22:48 p.m. EDT during a launch window that closes five minutes later at 5:27:47 p.m. EDT - a final adjustment of the launch time will be made at the T-9 minute hold to more precisely align with the space station's orbit.

Weather remains a major concern. Thick clouds are forecast to develop over the Kennedy Space Center accompanied by stiff crosswinds that may exceed limits at the Shuttle Landing Facility. The official weather forecast calls for only a 40 percent probability of acceptable conditions at launch time.

NASA launch commentary has just started and video is being broadcast of the seven astronauts entering Endeavour in preparation for today's launch attempt.

Shuttle Endeavour's external tank is filled with a half-million gallons of super-chilled liquid hydrogen and liquid oxygen for this afternoon's launch attempt. Fueling, or "tanking," operations started at 8:41 a.m. - about 40 minutes late - and were completed at 11:32 a.m. EDT. The vehicle is now in "stable replenish" mode and its massive fuel tank will continue to be topped-off until launch time.

Launch is scheduled for 5:22:48 p.m. EDT during a launch window that closes five minutes later at 5:27:47 p.m. EDT - a final adjustment of the launch time will be made at the T-9 minute hold to more precisely align with the space station's orbit.

No technical problems are being reported at pad 39A as the countdown clock continues to tick down. The launch team continues to closely monitor weather conditions along Florida's Space Coast as puffy clouds float over the Kennedy Space Center.

Earlier forecasts of thick clouds over the launch site may not materialize and the astronauts have been informed that, as of now, weather conditions are 'Go' for launch. Winds at the Shuttle Landing Facility are also being closely monitored for Return-to-Launch-Site abort constraints.

Shuttle Endeavour sits poised on pad 39A at the Kennedy Space Center as the countdown has entered the built-in hold at the T-20 minute mark. Today's launch time has been adjusted by one second to 5:22:49 p.m. EDT to more closely align with the space station's orbit - the window closes five minutes later.

The seven member crew, led by veteran commander Ken Cockrell and Franklin Chang-Diaz who is making his record-tying 7th space mission, are positioned inside the Orbiter awaiting their launch attempt. Endeavour is also transporting three members of the ISS Expedition 5 crew, led by Russian cosmonaut Valery Korzun, who will replace the Expedition Four crew now onboard the station.

The Shuttle Training Aircraft, flown by astronaut Charlie Precourt, is keeping an eye on the weather conditions around Central Florida and reporting his findings to launch managers.

At this time, weather conditions are acceptable to support both launch and emergency landing scenarios, but clouds building to the west of the launch site are being closely watched.

Shuttle Endeavour has been cleared for launch from pad 39A at the Kennedy Space Center on its 12-day space station crew exchange mission. The countdown is now paused at the planned T-9 minute hold as final launch preparations are rushed to completion. Liftoff time is now set for 5:22:49 p.m. EDT - one second later than originally planned - to more closely align with the space station's orbit. Today's launch window closes about 4.5 minutes later at 5:27:23 p.m. EDT.

The seven member crew, led by veteran commander Ken Cockrell and Franklin Chang-Diaz who is making his record-tying 7th space mission, are positioned inside the Orbiter awaiting their launch attempt. Endeavour is also transporting three members of the ISS Expedition 5 crew, led by Russian cosmonaut Valery Korzun, who will replace the Expedition Four crew now onboard the station.

The Shuttle Training Aircraft, flown by astronaut Charlie Precourt, has been keeping an eye on the weather conditions around Central Florida and reports no conditions that would prohibit launch.

Shuttle Endeavour has just lifted off from pad 39A at the Kennedy Space Center on its 12-day space station crew exchange mission.

It will take almost nine minutes for Endeavour to reach orbit.

At the time of liftoff, the International Space Station was above the southern Indian Ocean west of Perth, Australia.

After almost a week's delay, shuttle Endeavour is safely in orbit.

NASA's newest orbiter returned to space after an apparently flawless launch from the Kennedy Space Center at 5:22:49 p.m. EDT.

The seven member crew, led by veteran commander Ken Cockrell and Franklin Chang-Diaz who is making his record-tying 7th space mission, will now chase down the International Space Station. Endeavour is transporting three new residents of the ISS, the Expedition 5 crew led by Russian cosmonaut Valery Korzun who will replace the Expedition Four crew now onboard the station.