Forecasters predict a 60 percent chance of favorable weather for launch of a SpaceX Falcon 9 rocket Thursday from NASA’s Kennedy Space Center in Florida to carry more Starlink broadband satellites into orbit.
The launch — set for 2:19 p.m. EDT (1819 GMT) Thursday — will add 60 more Starlink satellites to SpaceX’s ever-growing broadband network. SpaceX has launched more than 700 Starlink satellites to date, making the company the owner of the largest fleet of spacecraft in orbit.
Like the previous Starlink launches, a 229-foot-tall (70-meter) Falcon 9 rocket head northeast from Florida’s Space Coast with 1.7 million pounds of thrust from nine Merlin main engines, then shed its first stage booster about two-and-a-half minutes into the flight.
A single Merlin engine on the Falcon 9’s second stage is expected to fire two times before release of the stack of Starlink satellites in a near-circular orbit between 172 miles (278 kilometers) and 162 miles (261 kilometers), with an inclination of 53 degrees, according to pre-launch estimates.
Separation of the 60 Starlink satellites from the rocket is scheduled about 61 minutes after launch.
SpaceX plans to recover the Falcon 9’s first stage aboard the drone ship “Just Read the Instructions” positioned northeast of Cape Canaveral in the Atlantic Ocean, roughly due east of Charleston, South Carolina. The propulsive landing of the first stage is expected around eight minutes after liftoff.
The first stage on Thursday’s launch has flown two previous times, including the launch May 30 of two NASA astronauts on SpaceX’s Crew Dragon capsule, and the July 20 launch of South Korea’s Anasis 2 military communications satellite. One half of the clamshell-like payload shroud on Thursday’s mission is also a veteran of two previous Falcon 9/Starlink launches, according SpaceX.
SpaceX also plans to retrieve the payload fairing after Thursday’s launch. The two halves of the shroud are designed to descend under parachutes.
The mission Thursday will mark the 13th launch of Starlink satellites since SpaceX kicked off deployment of the network in May 2019. SpaceX’s most recent launch Sept. 3 carried up the previous 60 Starlink satellites.
The official launch weather forecast issued Wednesday by the 45th Weather Squadron at Cape Canaveral calls for a 60 percent chance of good conditions for liftoff of the Falcon 9 Thursday. The primary weather concerns Thursday will be with cumulus and anvil clouds associated with afternoon thunderstorms.
If the launch is delayed to Friday, there’s a 40 percent chance of acceptable weather conditions in the forecast.
SpaceX eventually plans to launch thousands of Starlink satellites, but the first tranche of Starlinks will number 1,440 spacecraft, according to Jonathan Hofeller, SpaceX’s vice president of Starlink and commercial sales.
“The total global constellation we’re targeting is 1,440 satellites, of which a good number of those are already on orbit,” Hofeller said.
Some of the satellites, including those on the first Starlink launch last May, are being moved to lower altitudes and deorbited.
Each flat-panel Starlink satellite weighs about a quarter-ton, and they are built at a SpaceX facility in Redmond, Washington, near Seattle. Extending on SpaceX’s penchant for building hardware in-house, the aerospace company is manufacturing its own Starlink satellites, user terminals and ground stations.
SpaceX’s Starlink megaconstellation is already the largest fleet of satellites in the world, but hundreds more will be launched in the coming months.
Hofeller said last month that SpaceX is building six Starlink spacecraft per day, and plans to launch Starlink missions at intervals of every two to three weeks until completing the initial Starlink network of around 1,440 satellites.
SpaceX has regulatory approval from the Federal Communications Commission to eventually operate nearly 12,000 Starlink satellites to blanket the planet with high-speed, low-latency Internet signals. SpaceX also also signaled plans to launch up to 30,000 additional Starlink satellites — beyond the 12,000 already approved — in filings with the International Telecommunication Union.
The Starlink network is one of two major development projects SpaceX is pursuing, alongside the company’s next-generation Starship super-heavy-lift rocket.
In a discussion at the ASCEND Space Science and Technology Summit last month, Hofeller said that the private beta testing is being rolled out in the Pacific Northwest. With roughly 700 satellites, the Starlink network has enough coverage to provide connectivity to users at high latitudes, but more launches are required to expand coverage to other regions.
SpaceX has asked people interested in participating in the public beta test phase to sign up on the Starlink website.
With the beta testing program now underway, SpaceX is collecting latency statistics and performing speed tests. The company says it’s pleased with the initial results.
SpaceX said earlier this month that the tests so far show the network has “super low latency” with download speeds greater than 100 megabits per second. That’s fast enough to stream multiple HD movies at once, and still have bandwidth to spare, according to SpaceX.
SpaceX has also begun testing spacecraft with inter-satellite laser links, which could eventually allow data traffic to flow through the network without going through ground relay stations. The first batch of Starlink satellites did not carry inter-satellite links
Hofeller hinted at upgraded Starlink satellites in his virtual presentation at ASCEND Space Science and Technology Summit last month
“With 1,440 satellites, that’s when we get 24/7 global coverage, and the plan is to not stop there,” Hofeller said. “We’ll continue to launch, and with each launch, we can provide more and more capacity. There’s never enough capacity. You can’t limit what your kids want to watch, and what your family wants to consume. So we’ll continue to densify the network.”
SpaceX will deorbit older Starlink satellites as upgraded spacecraft come online, according to Hofeller.
After the launch Thursday, SpaceX’s next mission is set to take off from pad 40 at Cape Canaveral Air Force Station on Sept. 30, when a Falcon 9 rocket will deploy the U.S. Space Force’s next GPS navigation satellite.
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