[ad_1]
The 60 SpaceX satellites are expected to be launched on Wednesday night and will start building a network of spacecraft in broadband orbit that could potentially number several thousand people. They are based on a new flat screen model, with krypton-powered plasma thrusters, high power antennas, and a hazard avoidance camera, SpaceX says it can warn of potential collisions with d other objects in space.
Each Starlink satellite weighs about 227 kg, according to SpaceX. Stacked together in the payload fairing of a Falcon 9 rocket, the 60 satellites weigh 15 tons (13,620 kg), making the cargo launched on Wednesday night the heaviest ever launched into SpaceX.
This new mass record defeats the weight of SpaceX's fully powered SpaceX Dragon Crew, which was launched on March 2 on an unmanned test flight to the International Space Station.
In a press kit released Wednesday morning, SpaceX revealed new information on the design and functionality of Starlink satellites. Each Starlink spacecraft has a flat-panel design with multiple high-speed antennas and a single solar panel, according to information published in the press kit.
Starlink satellites are equipped with Hall thrusters, which use electricity and krypton gas to generate momentum, maneuver into orbit, maintain altitude and guide the spacecraft into the atmosphere at the end of its mission.
Hall thrusters offer a more fuel-efficient form of propulsion than conventional liquid thrusters, but most satellites that use Hall thrusters consume xenon. Krypton is cheaper than xenon, but offers lower thrust efficiency, according to a 2011 article presented by engineers from the US Air Force and the satellite industry.
Satellites also host optical trackers for detecting space debris, which allows the unit to autonomously avoid collisions with other objects in space.
Proposals from SpaceX and other potential commercial broadband providers to launch thousands of new satellites into orbit raised questions about traffic management. SpaceX originally planned to launch the first batch of Starlink satellites in a 741-mile (1,150-km) higher orbit, but the company requested permission from the Federal Communications Commission last year to start operating the network at a lower altitude.
The FCC approved the application last month.
SpaceX officials said the lower operational altitude of the first Starlink satellites would help ease concerns about space debris. If a Starlink relay station in lower orbit fails, the atmospheric drag will bring the satellite back to Earth in about five years.
In addition, 95% of all components of this design burn rapidly in the Earth's atmosphere at the end of each satellite's life cycle, exceeding all applicable safety standards, with future iterative designs being on the ground. point to disintegrate, "said SpaceX in the press kit released earlier. Wednesday.
The Falcon 9 rocket, 70 meters high, is scheduled to take off from the launch ramp at Cape Canaveral Complex 40 for an hour and a half from 10:30 pm. EDT Wednesday (02:30 GMT Thursday).
According to the 45th US Meteorological Squadron, there is a 80% chance that the weather will be favorable for takeoff during the Wednesday night launch window. SpaceX plans to recover the first Falcon 9 stage relay, which had already completed two missions in September 2018 and in January on the company's drone, located a few hundred kilometers northeast of Cape Canaveral.
The mission will be the sixth SpaceX launch of the year and the 71st flight of a Falcon 9 rocket since 2010.
The 60 satellites packed above the Falcon 9 rocket for launch on Wednesday present a new satellite concept that SpaceX intends to mass-produce in a plant in Redmond, Washington, for equip a fleet of almost 12,000 nodes of low Earth orbit relays.
SpaceX has accurate information on the Starlink satellite configuration, including basic information such as the number of spacecraft to fly on the first rocket launcher of the company dedicated to the broadband network. Elon Musk, founder and CEO of SpaceX, revealed in a tweet Saturday that 60 satellites would be aboard the Falcon 9 rocket during its takeoff from the Space Coast of Florida.
Musk also tweeted an image of the 60 satellites stacked in launch configuration, ready to be encapsulated in the Falcon 9 payload fairing.
Starlink's SpaceX fleet is one of many commercial projects under development for beam-based Internet connectivity around the world. OneWeb launched the first six of its planned 648 satellites in February, with the launch of 100 additional satellites by the beginning of 2020.
And Amazon, backed by the fortune of billionaire Jeff Bezos, is looking to join the race to provide broadband services from satellite constellations.
SpaceX's Starlink fleet would cost about $ 10 billion, with nearly 12,000 Ku-band, Ka-band and V-band satellites positioned at different altitudes on several orbital planes. The first 1,544 Starlink satellites are expected to operate in orbits 550 km above the Earth, spread over 24 orbital planes inclined 53 degrees from the equator.
The Falcon 9 rocket will launch Wednesday 60 Starlink satellites about 62 minutes after takeoff. The launcher will target a 273 km (440 km) orbit for the separation sequence and the satellites will activate their Hall effect thrusters to increase their altitude in their operational orbit of 341 km.
SpaceX launched two Starlink demonstration satellites in February 2018 as payloads overlaid on a Falcon 9 launch from California. The gear launched Wednesday has a different design and is smaller than the test benches launched last year.
"SpaceX has designed Starlink to connect end-users to low-latency, high-bandwidth broadband services by providing continuous worldwide coverage with a network of thousands of Earth-orbiting satellites." bass, "said SpaceX in the press kit. "To make and launch such a constellation, SpaceX uses the same fast design approach that has led to the success of Falcon 1, Falcon 9, Falcon Heavy and Dragon.
"As such, Starlink's streamlined design is significantly more scalable and more efficient than its first experimental iteration," said SpaceX.
"This mission will push the operational capabilities of satellites to the limit," said SpaceX. "SpaceX expects to encounter problems along the way, but learning here is critical to developing reliable and affordable broadband service."
Email of the author.
Follow Stephen Clark on Twitter: @ StephenClark1.
[ad_2]
Source link