NASA is preparing to pick up the countdown to the planned launch of a Delta II rocket at Cape Canaveral Force Station tonight and the agency also firmed up plans to launch shuttle Discovery next Wednesday on an International Space Station assembly mission.The 12-story United Launch Alliance rocket and its payload -- a planet-hunting NASA space probe -- are slated to blast off from Launch Complex 17-B at 10:49 p.m.
NASA will have two, three-minute windows in which to put the Kepler spacecraft en route to its operational orbit. The first will extend from 10:49 p.m. through 10:52 p.m. and the second will be 11:13 p.m. through 11:16 p.m.
You can watch NASA TV coverage of the countdown and launch starting at 8:30 p.m. Simply click on the NASA TV box on the right hand side of this page to launch our NASA TV viewer and be sure to refresh this page for periodic updates.
The weather is expected to be near-perfect for launch. But prevailing winds is forcing NASA and United Launch Alliance to move its press site for the launch.
Press Site 1 at the air station sits a mile-and-a-half west of the two pads at Launch Complex 17, just east of the old NASA Mercury Mission Control Building. Air Force range safety officials fear that prevailing winds would carry a toxic cloud over Press Site 1 in the event of a launch failure early in flight. So the media will caravan to an alternative site at NASA's KARS Park off Hall Road on north Merritt Island.
Countdown clocks started ticking backward at 5:30 p.m. and then the terminal count will pick up at 7:48 p.m. A warning horn will sound around Launch Complex 17 and all those not involved with the countdown will clear a surrounding blast danger zone.
The first-stage of the Delta II will be fueled with RP-1 and liquid oxygen propellant beginning at 8 p.m. and C-Band radars that will track the vehicle in flight will be tested shortly thereafter. A weather briefing will be held and then engineers will begin loading liquid oxygen aboard the second stage of the vehicle around 9 p.m.
Range safety command receivers will be tested around 9:40 p.m. and then the rocket's engines will be slewed in a gimbal test to make certain they will steer properly in flight. Fuel tanks will be pressurized and range safety "safe & arm" devices will be tested before NASA's Kepler spacecraft is put on internal power four minutes before flight.
NASA Launch Director Omar Baez told reporters on Thursday that the NASA-ULA launch team is looking forward to executing the countdown and launch.
"We're ready to fly," he said.
You can follow along with the countdown the official United Launch Alliance Kepler Mission Booklet It contains information on countdown activities and the flight of the Delta II rocket.
The Air Force is asking mariners and aviators to steer clear of a launch danger zone off the coast of Cape Canaveral and restricted airspace around the launch site.
Click here for a map of the Launch Hazard Area off the coast of Cape Canaveral.
Click here for a map showing Restricted Airspace around the launch site.
Senior NASA managers earlier today set a firm launch date next Wednesday for shuttle Discovery and seven astronauts on a mission to haul a fourth and final set of massive American solar wings to the International Space Station.
NASA managers told reporters in a post-Flight Readiness Review news conference that a new testing technique and extensive engineering analyses prove that the shuttle is safe to fly even though it is equipped with suspect main propulsion system valves.
One of three gaseous hydrogen flow control valves failed during Endeavour's successful launch last November, and engineers have been analyzing the matter ever since.
About the size and shape of a pop-up lawn sprinkler, the poppet valves regulate the amount of gaseous hydrogen that is routed from the shuttle's three main engines to its external tank during flight.
The gaseous hydrogen keeps pressure within the tank at proper levels as propellant within it is exhausted by the main engines. The proper pressure is required to keep propellant flowing into the main engines at the right rate while making certain the thin aluminum-lithium tank does not collapse in flight.
Too little pressure could lead to an engine shutdown. Too much pressure could trigger a relief valve on the tank and dump highly combustible gaseous hydrogen overboard, creating a potential fire hazard.
A gaseous hydrogen leak in the shuttle's rear engine compartment could lead to a fire or explosion.
NASA engineers found that valves with small cracks are more susceptible to failure. The agency traditionally has used electron microscopy and dye penetration tests to detect cracks. But extensive analyses of valves in inventory showed small cracks have gone undetected after those tests.
NASA in the past month has been using a non-destructive technique known as an eddy current test to detect cracks. The process uses electromagnetic induction to detect subtle changes in current that are indicative of cracks.
The new technique was used to ferret out all valves in inventory with cracks. It also enabled NASA to identify three flawless valves to install on Discovery. The ability to prove the valves had no cracks large enough to lead to valve failures gave NASA the confidence to press ahead with the Discovery mission.
Liftoff time next Wednesday will be 9:20 p.m.
ABOUT THE IMAGE: Click to enlarge and save the United Launch Alliance image of the Delta II rocket on its launch pad after a giant Mobile Service Tower was moved away from the vehicle at Launch Complex 17-B earlier today. You can also click on the enlarged image to get an even bigger, more detailed view of the rocket and the mission emblems on the side of it as well as on the side of the umbilical tower. Look closely and you can see two hard-hat workers standing on the pad next to the 12-story rocket. Photo credit: Carleton Bailie, United Launch Alliance.
2 comments:
"the media will caravan to an alternative site at NASA's KARS Park off Hall Road on north Merritt Island"
Todd: forgive an Irish hack for pointing out that KARS is 5.73 miles from SLC 17; the outdoor deck of a well-known Tikki Bar is 3.95 miles from the action. I know which one I'd choose! Have a good one, Leo.
Leo: Good to hear from you. The switch to the alternative press site is unfortunate. But it is what it is. I know what your saying though. KARS Park is not a great choice. No video there. Only audio. I know some photographers are heading to Jetty Park instead.
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