If the weather and Falcon 9 rocket cooperate, the first set of SpaceX's Internet satellites will start from Florida Wednesday Evening. With a mass of 1
Wednesday's rocket will increase 60 Starlink satellites, weighing 227 kg, to a height of 440 km. This is the first block of Starlink satellites for what would ultimately be a much larger constellation, and they will help SpaceX measure performance and conduct multiple key system testing. In the coming months, these first satellites will be combined with six additional launches with equal payloads. These launches will bring the constellation to an initial "operational" capacity.
There is no guarantee that everything will be fine, said SpaceX founder Elon Musk during a telephone conference with reporters on Wednesday night. "This is very difficult," said Musk. "There is a lot of new technology, so it is possible that some of these satellites may not work. There is a small possibility that all these satellites will not work."
Launch and Release
The launch window opens at 10:30 am Wednesday (02:30 UTC Thursday) and closes 90 minutes later. A back-up launch window opens simultaneously on Thursday. The weather conditions are currently expected to be 80 percent favorable for launch.
The initial part of the launch will be familiar to people who have seen a SpaceX launch before. This Falcon 9 first stage has flown twice before, and it will attempt to land on Course I Still Love You droneship in the Atlantic. The real action will take about 1 hour 2 minutes after the start, when the second step begins to deploy the Starlink satellites.
– Elon Musk (@elonmusk) May 12, 2019
To save mass, each of the 60 satellites will not have its own release mechanism , such as a spring. Instead, Musk explained, the upper stage of the Falcon rocket will begin a very slow rotation, and each of the satellites, in turn, is released with a different amount of rotational inertia.
"It almost seems like spreading a short card on a table," said Musk. There may actually be some contact between the Starlink satellites, he added, but they are designed to handle it.
After installation, the satellites will boot their ion units and open their solar panels. They will move to a height of 550 km under their own power. Musk said he is concerned about the solar panel deployment, and he noted that there are two different installation mechanisms on the satellites for this purpose. He also said that the satellites have incorporated new technologies with the thruster and phase-based antennas that have not yet been fully tested in space.
The satellites are designed to control costs. For example, one will operate with Hall-effect thrusters-ion thrusters, in which propellants are accelerated by an electric field. The conventional fuel for such a thruster is xenon, which provides high performance. However, the Starlink satellites will use another noble gas: krypton. It has a lower density, so the satellite fuel tanks must be larger and have less performance than xenon. But krypton can be purchased in just a tenth of the cost of xenon, which means if a company wants to burn thousands of satellites.
"It costs a heck of much less than xenon," says Musk about krypton. (He also shook, in response to an Ars question on this fuel, that the satellites would be immune to invasion from Superman's domestic world.)
During the conversation, Musk said every Starlink satellite cost more to deliver in circulation than the manufacturing costs. The list price for a Falcon 9 launch is $ 62 million. Factoring in reuse discounts and wholesale prices means that the Starlink satellites cost significantly less than $ 1 million to build.
SpaceX competes with about half a dozen other companies to develop low latency, high bandwidth Internet from space. One competitor, OneWeb, launched six of its own satellites in February. But SpaceX seems to be way ahead of most of the rest of the field.
With six new launches and a total of about 400 satellites, Musk said the constellation with grace could offer some initial connections to land-based users. A dozen launches would provide "significant" connectivity, he said, and 24 launches would provide close worldwide service.
After several recent financial reports, SpaceX has sufficient capital to launch the first 400 satellites and start selling the service to telecom companies and governments that want to serve low and medium density populations. If there were significant issues with the expansion or execution of the first 400 satellites, he said SpaceX would have to return to the capital markets.
Over time, Musk Starlink foresees to become a commercial success for SpaceX and enable its goal to build a self-supporting city on Mars. Potential launch revenue increases to about $ 3 billion per year for the company, but it is only 3 percent of the global internet market that can take around $ 30 billion. "We see this as a way for SpaceX to generate revenue that can be used to develop more and more advanced rockets," he said.
Musk acknowledged the validity of worries about orbital waste from so many satellites (SpaceX is authorized to launch more than 11,000 Starlink satellites, far more than the total number present in circulation in about 2000). But he also said the chosen height of 500km and the design of the satellites will help the constellation cleanse itself due to the interaction with the Earth's atmosphere.
The launch webcast, embedded below, should begin about 15 minutes before launch.  Starlink mission launch.