On Thursday night, SpaceX launched a batch of 60 internet communications satellites from Cape Canaveral Air Force Station in Florida.
More than one hour later, some 270 miles above Earth, the cluster of satellites — part of a system called Starlink — pushed off from the rocket that carried it to orbit. The individual satellites slowly began to drift toward their singular journeys above the planet.
Elon Musk, the company’s founder and chief executive, said on Twitter early on Friday morning that all 60 satellites were “online.”
By next year, SpaceX hopes that hundreds of the devices could be circling the planet, beaming high-speed internet service everywhere. It could allow SpaceX to enter a new business that might generate revenue to finance the dream of sending people to Mars.
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It was the third attempt to launch the Starlink system, after two earlier postponements last week.
What was the rocket carrying?
SpaceX — which usually ferries cargo to orbit for NASA or private companies — is its own customer this time. And the Falcon 9 rocket was not carrying just one satellite, but 60 identical ones.
Mr. Musk posted pictures of the Starlink satellites on Twitter earlier this month.
The Starlink satellites will eventually form a constellation of satellites that are to offer internet to almost anywhere on Earth.
Last year, SpaceX launched two prototype satellites, called Tintin A and Tintin B.
The payload on this launch, at more than 30,000 pounds, was the heaviest ever launched by SpaceX, Mr. Musk said during a news conference last week ahead of the postponed launch attempts. He added that these satellites would be able to relay information by bouncing the data off a ground station. However, they lack a component planned for future versions: lasers that would allow the satellites to relay information to one another.
Each of the flat-panel satellites weighs about 500 pounds, powered by a single solar array. During their deployment, they moved steadily outward from a slowly spinning core. “It will almost seem like spreading a deck of cards on a table,” Mr. Musk said.
Mr. Musk sounded a note of caution to tamp down expectations. “There is a lot of new technology here,” he said. “It’s possible that some of these satellites may not work. In fact, it’s possible, a small possibility, that all of the satellites may not work.”
Isn’t there already internet service from space?
A number of companies provide satellite internet using geostationary communications satellites 22,200 miles above the surface. At that altitude, the time for the satellite to complete an orbit is exactly one day, and thus it remains over the exact same spot on Earth as the planet rotates at the same rate.
That makes it straightforward for one satellite to provide internet for a swath of the surface below, but current services have drawbacks. They are not available everywhere, and they are usually fairly expensive.
Because the data signals have to travel up 22,200 miles and then back down, the performance can be laggy. That does not matter if you are watching a movie on Netflix, but it becomes excruciating when playing an online game that relies on fast reflexes.
What’s different about Starlink?
The Starlink satellites will orbit much lower — between 210 and 710 miles above the surface. That reduces the lagginess, or latency. SpaceX has said performance should be comparable to ground-based cable and optical fiber networks that carry most internet traffic today. Starlink would provide high-speed internet to parts of the world that currently are largely cut off from the modern digital world.
Because the satellites are lower, they travel faster. Thus, Starlink must provide a constellation of satellites whizzing around the planet. When one satellite moves away from one of its customers, another one must come into view in order to provide a continuous internet connection.
Mark Juncosa, vice president for vehicle engineering at SpaceX, said that with 12 additional launches, SpaceX could provide good coverage over the United States; 24 launches would put enough satellites to cover most populated areas; and 30 would cover the entire world.
If Starlink is successful, more satellites would be added to send and receive greater volumes of data.
Are other companies also looking to launch constellations of internet satellites?
Starlink’s competitors include OneWeb, Telesat and Amazon.
Why is SpaceX, a rocket company, going into the internet business?
For Mr. Musk’s dream of sending people to Mars, he is developing a giant spacecraft called Starship. He noted that SpaceX’s rocket launching business might grow to about $3 billion a year. By contrast, internet revenue could bring in $30 billion a year for the company, Mr. Musk said.
“We see this as a way for SpaceX to generate revenue that can be used to develop more and more advanced rockets and spaceships,” Mr. Musk said. “We think this is a key steppingstone on the way to establishing a self-sustaining city on Mars and a base on the moon.”
Mr. Musk acknowledged that history is full of companies dragged into financial ruin by attempting to build ambitious constellations of communications satellites.
“I believe none have successfully gone into operation without going bankrupt,” he said. “I do believe we will be successful, but it is far from a sure thing.”
What about orbital debris?
There are about 2,000 operational satellites around Earth. That number will multiply as constellations like Starlink are deployed.
“A majority of the satellites in orbit will be SpaceX, if things go according to plan,” Mr. Musk said. “That is a big if, of course.”
The worry is what happens when satellites die. The proliferation of satellites will greatly increase the risks of collisions, and the many pieces of debris would in turn pose danger to other satellites. Mr. Musk said each Starlink satellite would possess data on orbits on all known pieces of space debris and automatically steer away from any that might cross its path.
With so many satellites, there will also be much more debris falling from space in the coming years.
SpaceX said that 95 percent of a Starlink satellite would burn up on re-entry, but that would still mean that about 25 pounds of debris — in particular, an ion thruster that is part of the propulsion system and steel reaction wheels that keep the spacecraft pointed in the correct direction — would reach the surface. In a letter to the Federal Communications Commission on March 13, the company said that it had changed the design so that future versions of the satellites would be entirely destroyed during re-entry.
The chances of any one crashing satellite’s hurting or killing someone are small; the danger to you individually is negligible. But adding up the risks of tens of thousands of satellites to the 7.5 billion people on Earth, the probability of someone’s being hurt somewhere becomes more significant.