SpaceX has canceled a countdown for Falcon 9 on Wednesday, as Florida's space coast is threatened with thunderbolts that delay the departure of a cargo mission to the International Space Station by Thursday.
But the weather conditions are It is not expected that Thursday afternoon will be much better when SpaceX has another immediate launch window at 18:01:56 EDT (2201: 56 GMT) to take a kite cargo ship to the space station to send.
Widespread thunderstorms streaming from southwest to northeast across Central Florida brought rain and thunder to Cape Canaveral. Despite a gloomy forecast, SpaceX continued to load kerosene and liquid oxygen propellants into the two-stage Falcon 9 rocket, with the countdown counting on a scheduled start at 18:24:30. EDT (2224: 30 GMT).
Two start weather rules regarding surface electric fields and anvil clouds remained "no go" for the start, as the countdown was approaching zero. SpaceX broke the countdown at T-minus 30 seconds, and the teams began the procedures to empty the Falcon 9 of its liquid propellants and prepare for another attempt on Thursday.
"Hold, Hold, Hold, Countdown 1", a member of SpaceX's launch team called the countdown net after T-minus 30 seconds.
"Startup abort script is running," another engineer said.
"Please continue with … after the static fire extinguishing operations."
SpaceX hopes to be fortunate to begin Thursday's Company's 18th replenishment mission to the International Space Station under a billion dollar agreement with NASA. The Dragon Cargo Pod is filled with 2,312 kilograms of provisions, equipment and experiments for the Station's six-man Expedition 60 crew.
But the 45th Weather Squadron of the Air Force, which publishes weather forecasts for space missions leaving Cape Canaveral, expected on Thursday similar conditions as the spaceport on Wednesday afternoon. An updated forecast released Wednesday night predicts a 70 percent likelihood that weather conditions will prevent Thursday's start.
As on Wednesday, there is a risk on Thursday that storms will violate the rules for anvil clouds, cumulus clouds and lightning.
For the lightning rule, the Air Force Range weather team is tracking lightning strikes to ensure that no discharges have occurred within a 10-mile radius of the launch pad or within 10 miles of the Falcon 9 rocket's flight path.
The rules for anvil clouds address concerns about missile-fired lightning.
"These are a bit more scary for us, as it looks like the weather is clear and there may not have been a lightning strike in the last 30 to 45 minutes. But if you could send a rocket through this (anvil) cloud This cloud will still be charged enough to trigger extra lightning strikes, "said Will Ulrich, the starting weather officer of the 45th Weather Squadron, during a press conference ahead of Wednesday's start.
If the launch does not start on Thursday, NASA and SpaceX may have to wait up to a week for the next chance to send the Dragon Cargo ship toward the International Space Station.
The position of the space station in orbit prevents the launch of the spacecraft Dragon on certain days, and a Russian supply ship of the brand Progress is scheduled to leave the orbit complex on July 29 and provide the stage for docking a new spaceship Progress Supply Freighter 31. July.
Typically, a Dragon cargo ship takes two or three days to reach the space station after the launch of Cape Canaveral. If the mission can start today, SpaceX's own cargo plane will arrive at the space station on Friday.
NASA and SpaceX are looking for another launch option in busy station traffic. Otherwise, the next start attempt could take place after Thursday still on 1 August, it said.
The refill mission was due to launch on July 21st, but SpaceX delayed the flight three days after repairing an oxygen leak. Launch preparations were delayed during the first week of the Falcon 9 last week.
Dragon Cargo's Cargo Cargo includes the International Docking Adapter-3 (IDA-3), a mechanism for connecting commercial crew capsules from Boeing and SpaceX ferries to and from the station. NASA paid for the third international docking adapter to replace the first IDA unit lost in June 2015 when spaceX was launched.
SpaceX successfully delivered the second IDA to the station in July 2016, and SpaceX's Crew Dragon spacecraft first used the docking mechanism earlier this year during a non-flown test flight docking with the orbiting research outpost.
Other elements of the Dragon mission are 40 mice, which allow researchers to assess the effects of space travel on their immune system, their organs, muscles and bones. NASA also flies a space suit into the pressurized compartment of the kite freighter, which is to be used by astronauts on spacewalks.
After a stay of about a month on the space station, the Dragon Spaceship will depart and return to Earth to parachute into the Pacific Ocean, bring home research samples for analysis, and another space suit for renovation.
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