For the second consecutive day, SpaceX announced a Falcon 9 launch attempt at Cape Canaveral on Thursday evening, this time to complete a software update for the first 60 satellites for the company's Starlink network to deliver fast internet from a job.
SpaceX canceled the Thursday evening start attempt, which was set at 10.30 am. EDT (Friday 0230 GMT), approximately three hours before the opening of the start window.
In a tweet, the company said it would "stop updating satellite software and recheck everything."
The cargo on the Falcon 9 rocket awaiting launch consists of 60 flat voltage satellites to build SpaceX & # 39; s Starlink network, a fleet that could count thousands of small spacecraft in the coming years, offering broadband connectivity to consumers all over the world.
SpaceX has not set a new mission start date, the first Falcon 9 launch dedicated to the Starlink project.
"Always wanting to do everything we can to maximize the success of a mission, launch the next opportunity in about a week," tweeted SpaceX.
SpaceX scrubbed a previous countdown on Wednesday evening due to wind stagnation above the highest level.
The 60 satellites aboard the Falcon 9 were built in a new SpaceX plant in Redmond, Washington. The spacecraft is equipped with high-power, phase-driven antennas for transmitting internet signals and krypton ion impellers for propulsion.
The Falcon 9 rocket will free the satellites, each weighing around 500 pounds (227 kilograms), in orbit around an hour after the launch of Cape Canaveral.
The 60 satellites will be uniquely separated from the upper phase of the Falcon 9, says Elon Musk, the founder and CEO of SpaceX.
"It looks a little different than people are used to," Musk told reporters on Wednesday during a conference call. "It will be a very slow implementation where we rotate the stage, and each of the satellites in the stack has a slightly different amount of rotation guarantee.
"So there is no real spring-based or specific satellite implementation mechanism," he said. The satellites will be deployed, it is almost like spreading a pack of cards on a table. This will be a bit weird compared to normal satellite implementations. "
Multi-payload dispensers launched on top of rockets usually release satellites in pairs, or one at a time, with a physical separation mechanism, such as a spring or pyrotechnic bolts.
The webcast from SpaceX shows the inset through the image of a camera mounted on the top stage of the rocket.
"There may be a little bit of contact between the satellites, but it is very, very slow and the satellites are designed to work with it," said Musk. "But we wanted to avoid having 60 different implementation mechanisms for the satellites. We expect that they will be switched on shortly after implementation. They will heat up the ion drive and go through a number of health checks."
The 60 Starlink satellites are based on a new design designed by SpaceX engineers. They are lighter and use a different separation scheme than two prototype Starlink satellites that SpaceX introduced last year.
"We should know if they are in good shape, probably about two or three hours after commissioning, so three or four hours after launch," he said.
The launch of Falcon 9 aims to release the Starlink satellites about 440 kilometers above the Earth, and the spacecraft's own thrusters will boost their orbits to 341 miles (550 kilometers) to begin technological demonstration trials.
"This is one of the most difficult engineering projects I have ever seen and it is really well executed," said Musk. "There is a lot of new technology here and it is possible that some of these satellites will not work, and in fact a small chance that all satellites will not work.
"We don't want to count anything until it comes out, but these are, I think, a great design and we've done everything to maximize the chance of success," he said.
Previous initiatives to create an extensive communication network in a low orbit around the earth, a regime a few hundred kilometers above the earth, have experienced technical and financial headwinds. Traditional communication satellites fly in higher geostationary orbits more than 22,000 miles (nearly 36,000 kilometers) above the equator, with a single spacecraft that covers a large geographical area.
In lower orbits, the Starlink satellites bounce user-to-user signals through a complex web of radio connections through ground stations and ultimately via inter-satellite laser links.
"The purpose of the Starlink system is to provide high bandwidth and low latency connectivity, ideally all over the world, subject to regulatory approval, and this would provide connectivity to people who do not have connectivity today, or where it is extremely expensive and unreliable. As well as offering options for people who may have connectivity in developed areas of the world today, but it is very expensive, "said Musk. "This will offer them a competitive option."
Starlink is one of many companies working on constellations of small broadband satellites in low orbit around the earth. OneWeb launched its first six satellites in February, with plans to spend hundreds more in orbit over the next two years, and Amazon says it plans to build a network consisting of thousands of internet service satellites.
"There is a lot of basic goodness about Starlink," he said. "We just want to know for sure that there are the right restrictions. There is a lot of technology, this is very difficult, and frankly in the past, the success of low orbit constellations, I believe none of them are successfully in use was taken without going bankrupt. "
SpaceX has received approval from the Federal Communications Commission for nearly 12,000 Starlink satellites broadcasting on Ku-band, Ka-band and V-band frequencies, with groups of spacecraft at different heights in low orbit positioned. But the first focus is on launching hundreds of satellites to set up a network that covers most of the world's population.
"It is important to distinguish between the initial operational capacity, which is around the level of 400 satellites, and then a significant operational capacity, around the 800 satellite level, and then it is about adding more and more satellites and more orbits from satellites as we get more use of the system and we get bandwidth limited, "Musk said. "You don't need anywhere near 10,000 satellites to be effective. … We start selling the initial service around the 400th launch of the satellite and then ensure that our production and launch of satellites meet user demand stay. "
After the first Starlink launch, SpaceX plans between two and six additional Starlink missions later this year to begin the first phase of the network in orbit, around 350 km above the earth, said Gwynne Shotwell, president and chief operating officer of SpaceX.
"This next set of satellites will really be a demonstration set for us to see the deployment schedule and pull our network together," Shotwell said at a industry conference last week.
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