Meteorologists predict a 60% chance of favorable weather for a SpaceX Falcon 9 rocket launch Thursday from NASA’s Kennedy Space Center in Florida to carry more Starlink broadband satellites into orbit.
The launch – set for 2:19 pm EDT (1819 GMT) on Thursday – will add another 60 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 previous Starlink launches, a 229-foot (70-meter) tall Falcon 9 rocket heads northeast from Florida’s Space Coast with 1.7 million pounds of thrust from nine Merlin main engines, then loses its first stage of thrust approximately twice – Half a minute from the start of the flight.
A single Merlin engine on the Falcon 9’s second stage is expected to fire twice before releasing the Starlink satellite stack in a nearly circular orbit between 172 miles (278 kilometers) and 162 miles (261 kilometers), with an inclination 53 degrees, according to pre-launch estimates.
The separation of the 60 Starlink satellites from the rocket is expected approximately 61 minutes after launch.
SpaceX plans to recover the first stage of the Falcon 9 aboard the “Just Read the Instructions” drone ship located northeast of Cape Canaveral in the Atlantic Ocean, roughly east of Charleston, South Carolina. propulsion of the first leg is expected about eight minutes after take-off.
The first leg of Thursday’s launch has flown twice previously, including the May 30 launch of two NASA astronauts on SpaceX’s Crew Dragon capsule and the July 20 launch of South Korea’s Anasis 2 military communications satellite. According to SpaceX , half of Thursday’s mission clamshell payload is also a veteran of two previous Falcon 9 / Starlink launches.
SpaceX also plans to retrieve the payload fairing after launch on Thursday. The two halves of the shroud are designed to descend under the parachute.
The mission on Thursday will mark the thirteenth launch of the Starlink satellites since SpaceX initiated deployment of the network in May 2019. SpaceX’s most recent launch on September 3 brought the previous 60 Starlink satellites.
The official launch weather forecast released Wednesday by the 45th Weather Squadron in Cape Canaveral calls for a 60% chance of good conditions for the Falcon 9 to take off on Thursday. The main weather on Thursday will be with mounds and anvils associated with afternoon thunderstorms.
If the launch is postponed to Friday, there is a 40% chance of acceptable weather conditions in the forecast.
SpaceX plans to launch thousands of Starlink satellites, but Starlink’s first tranche will consist of 1,440 spacecraft, according to Jonathan Hofeller, Starlink’s vice president and commercial sales at SpaceX.
“The total global constellation we are targeting is 1,440 satellites, of which a good number are already in orbit,” Hofeller said.
Some of the satellites, including those from Starlink’s first launch last May, have been moved to lower altitudes and deorbitated.
Each flat-panel Starlink satellite weighs about a quarter of a ton and is built in a SpaceX facility in Redmond, Washington, near Seattle. Extending SpaceX’s penchant for building hardware in-house, the aerospace company is manufacturing its own Starlink satellites, user terminals and ground stations.
SpaceX’s megaconstellation Starlink 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 a day and plans to launch Starlink missions every two to three weeks until it completes the initial Starlink network of approximately 1,440 satellites.
SpaceX has regulatory approval from the Federal Communications Commission to eventually run nearly 12,000 Starlink satellites to cover the planet with high-speed, low-latency Internet signals. SpaceX has also reported plans to launch up to 30,000 additional Starlink satellites – over the 12,000 already approved – in storage with the International Telecommunications Union.
The Starlink network is one of two major development projects SpaceX is carrying out, along with the company’s next-generation Starship super-heavy rocket.
In a discussion at the ASCEND Space Science and Technology Summit last month, Hofeller said private beta testing is being rolled out in the Pacific Northwest. With around 700 satellites, the Starlink network has enough coverage to provide connectivity to users in high latitudes, but more launches are needed to expand coverage to other regions.
SpaceX has asked people interested in participating in the public beta test to register on the Starlink website.
With the beta testing program now underway, SpaceX is collecting latency statistics and running speed tests. The company says it is happy with the initial results.
SpaceX said earlier this month that tests so far show the network has “super low latency” with download speeds in excess of 100 megabits per second. It’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 passing through ground-based relay stations. The first batch of Starlink satellites did not carry inter-satellite links
Hofeller hinted at the updated Starlink satellites in his virtual presentation at the ASCEND Space Science and Technology Summit last month
“With 1,440 satellites, this is where we get global 24/7 coverage, and the plan is not to stop there,” said Hofeller. “We will continue to launch and with each launch, we can provide more and more capacity. There is never enough capacity. You cannot limit what your children want to watch and what your family wants to consume. So we will continue to densify the network.”
SpaceX will be disorbing old Starlink satellites as soon as the updated spacecraft go online, according to Hofeller.
After launch on Thursday, SpaceX’s next mission will take off from Cape Canaveral Air Force Station Pad 40 on September 30, when a Falcon 9 rocket deploys the US Space Force’s next GPS navigation satellite.
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