SpaceX Launched 60 Internet-Beaming Satellites Into Orbit

Science
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Smith sonian mag
SpaceX is one step closer to achieving its goal of bringing internet to the masses. On Thursday evening, the company’s fifth Falcon 9 launch of the year went off without a hitch (following a week-long delay due to poor weather conditions and technical issues) as the rocket leapt off its Florida launch pad at 10:30 p.m. EDT, carrying a stack of 60 internet-beaming satellites to orbit. These are just the first of nearly 12,000 planned satellites the California-based company plans to launch in the next six years as part of an ambitious initiative SpaceX calls Starlink .
Prior to launch, SpaceX CEO Elon Musk tweeted a photo of all 60 satellites stacked tightly inside the Falcon 9’s cavernous nosecone, filling almost all the available space. With each flat-panel satellite weighing in at about 500 pounds (227 kilograms) each—or 15 tons total—this is easily one of the heaviest payloads the Falcon 9 has ever carried to orbit and subsequently had enough fuel left to make the trek back to Earth. The booster doing all the heavy lifting is a veteran member of SpaceX’s growing fleet of reused boosters. Unofficially dubbed B1049.3 (an internal identifier by SpaceX), the rocket used in Thursday’s flight already had two missions under its belt, having ferried a communications satellite into orbit in September 2018 and the final group of 10 satellites for the telecom giant Iridium in January of this year. After successfully depositing all 60 of the satellites into orbit, the booster returned to Earth, gently touching down approximately eight minutes after liftoff on the company’s drone ship, “Of Course I Still Love You,” waiting out in the Atlantic Ocean.
First 60 @SpaceX Starlink satellites loaded into Falcon fairing. Tight fit. pic.twitter.com/gZq8gHg9uK
— Elon Musk (@elonmusk) May 12, 2019
SpaceX live streamed the launch, and even showed the deployment of all 60 Starlink satellites, which occurred just over an hour after launch. What’s unique about this mission, is that instead of using spring mechanisms to deploy each satellite, SpaceX engineers have opted to use the satellites' own inertia.
During a media conference call on May 15, Musk detailed how exactly this would work. “The Falcon 9 upper stage will rotate, and the Starlink satellites will deploy like cards spreading on a table,” he said. “They might actually contact each other during deployment, but they're designed to handle that.”
As one of SpaceX’s more formidable projects, Starlink is quite complex. According to filings with the Federal Communications Commission (FCC), SpaceX plans on building its mega constellation in two parts: an initial batch of 4,409 satellites that will operate between 340 miles (547 kilometers) and 823 miles (1,325 kilometers) up, and a second batch of 7,518 satellites that would fly slightly lower, between 208 miles (335 kilometers) and 214 miles (345 kilometers) in altitude. If all goes as planned, nearly 12,000 satellites will work in tandem to connect the world below.
“This was one of the hardest engineering projects I’ve ever seen done, and it’s been executed really well,” SpaceX CEO Elon Musk said during the same call.
SpaceX launched its first bits of the Starlink program in 2018 , as two prototype satellites, dubbed TinTin A and TinTin B , hitched a ride to orbit along with another satellite. That test mission went well, despite the duo flying in a lower-than-planned orbit. SpaceX says the data collected from the mission influenced their decision to ask the FCC to allow part of the planned constellation to fly in a lower orbit; the FCC subsequently agreed . However, the agency stipulated that SpaceX must launch at least half of its full constellation by 2024 .
First two Starlink demo satellites, called Tintin A & B, deployed and communicating to Earth stations pic.twitter.com/TfI53wHEtz
— Elon Musk (@elonmusk) February 22, 2018
Thursday’s launch is the first major step in achieving that goal. This first batch of satellites are operational, but lack some of the features that the finalized versions will rely on—including the ability to communicate between satellites. However, they will help SpaceX better understand what it takes to deploy and operate a large flock of satellites in space. The initial flock is equipped with radio antennas to communicate with Earth, thrusters that can propel them through space, and star trackers for navigation. But that’s not all. SpaceX also claims the satellites can autonomously track other debris on orbit thanks to NORAD tracking data . Much like collision avoidance features in your car, according to Musk, the satellites will be able to detect and avoid potential collisions with other objects in space.
Future iterations of the satellites will be able to do something this initial batch cannot: talk amongst themselves—a key feature in order for the satellites to continuously hand over coverage as the flock sails over the Earth. However, Musk did explain that there’s a workaround: the satellites can bounce signals off of receivers on the ground, and back up to other satellites. “That way we can get connectivity without using intersatellite links,” Musk says. “The system can still have global connectivity,” but Musk says this solution is only necessary for the first few batches of production satellites. After that, the satellites will be equipped with laser links to talk back and forth.
Ultimately, SpaceX hopes this endeavor will provide global internet coverage from space, and do so affordably and with reduced lag times—something that current satellites cannot. Current satellite internet providers beam internet coverage down from a higher orbital perch, in what’s known as geostationary orbit (which is typically 22,000 miles above the Earth). Because the signal has to travel such a long distance, the time it takes to send and receive data is substantially longer and more akin to the days of dial-up. By operating in low-Earth orbit, SpaceX hopes to cut down on this issue.
However, when you move to lower orbits, you need a lot more satellites to provide the same coverage, thus creating a need for thousands of satellites in order to fill a constellation and provide the coverage that SpaceX is proposing. Prior to Thursday’s launch, Elon Musk explained that at least six additional launches (of 60 satellites each) are needed for minimal coverage, and that another dozen would provide moderate coverage over the United States. (Currently, SpaceX only has permission to provide coverage to the United States, but is working with other countries to provide more global coverage.)
SpaceX is not the only company hoping to connect the world; companies like OneWeb, TeleSat, and even Amazon are throwing their hat in the space internet ring. OneWeb launched its first six satellites in February, but with this launch SpaceX is poised to be the first to provide significant coverage. But that coverage could come at a price, some industry folks warn. Space debris is already a big cause for concern, but with multiple mega constellations like Starlink planned for the near future, SpaceX says it has thought ahead.
In addition to the satellite’s autonomous collision avoidance capabilities, and the positioning of some of its fleet to a lower orbit, the company also plans to dispose of decommissioned satellites over water, and says that they’ll burn up almost completely in the atmosphere during re-entry. “When they deorbit, they don’t rain debris,” Musk explained. “[The satellites] don’t pose a risk to public safety.”
Musk also says that while the threat of space junk is real, the chances of collisions actually happening in space will be relatively small. “About the space junk thing: we don’t want to trivialize it or not take it seriously, because we certainly do take it seriously, but it’s not [that] crowded up there,” says Musk.
According to Musk, the benefits of these constellations are immense, especially in more rural and remote areas. “This would provide connectivity to people that either don’t have any connectivity today, or where it’s extremely expensive and unreliable,” he says. Additionally, he says this system would “provide a competitive option” to people in more developed areas who might want another (potentially cheaper) internet provider.
SpaceX also plans to roll out ground stations and user terminals that will receive the signals from the satellites. The user terminals will differ from traditional satellite dishes that are commonly installed. Described by Musk as flat, pizza-shaped antennas, all the receiver has to do is merely point upwards to work. It can work on a car, boat or plane, for instance, and Musk says that “unlike a dish that has to point very precisely, you can put it at almost any angle that is reasonably pointed at the sky.” He went on to add that it electronically steers its beam to communicate with the satellites overhead.
If all goes as planned, Musk hopes this endeavor will not only be one of goodwill, changing people’s lives by connecting them to rest of the world, but also be very profitable for SpaceX. “Total internet connectivity revenue in the world is on the order of a trillion dollars, and we think maybe we can access about 3 percent of that, or maybe 5 percent,” he says. If so, that means the revenue could fund many future projects, including the development of SpaceX’s massive new rocket called Starship, and even bases on the Moon or Mars.
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