CAPE CANAVERAL SPACE FORCE — SpaceX successfully launched more than 50 Starlink satellites late Saturday night.

The Falcon 9 rocket left Space Launch Complex 40 at Cape Canaveral Space Force Base at 11:50 p.m. ET, as it sent 54 Starlink satellites into low-Earth orbit.

The rocket originally was scheduled for launch at 12:40 a.m. Friday. At around T-40 seconds of the launch countdown, a SpaceX official was heard over the company’s live stream calling for a hold, followed by, “aborting launch automation. Launch abort is running.”

SpaceX did not give a reason for scrubbing the launch.

“Keep in mind that the purpose of the countdown is to help us catch any issues prior to flight. There are a thousand ways to launch a rocket and there’s only one way that it can go right,” Atticus Vadera, a propulsion engineer at SpaceX, said during the live stream.

Because the launch was instantaneous (meaning the Falcon 9 rocket had to launch at that exact moment), it rescheduled the launch attempt initially for Saturday, July 15, at 12:15 a.m. ET, according to SpaceX.

But later Friday, SpaceX posted on its website that it would try again at 11:50 p.m. ET Saturday. No explanation was given. If needed, another launch opportunity is available at 11:24 p.m. Sunday, SpaceX stated.

Discover more about NASA’s weather criteria for the Falcon 9 rocket here.

The first-stage booster B1060 is assigned to the Starlink Group 5-15 mission and it already has 15 successful missions under its belt:

• GPS III-3
• Turksat 5A
• Transporter-2
• Transporter-6
• Intelsat G-33/G-34
• 10 Starlink missions

After the stage separation, the Falcon 9's booster landed on the droneship A Shortfall of Gravitas that was out in the Atlantic Ocean.

About the mission

The Starlink Group 5-15 mission sent 54 Starlink satellites to low-Earth orbit. Starlink, a company owned and operated by SpaceX, provides internet services to parts of the world.

Before Saturday night's launch, the current number of Starlink satellites — recorded by Harvard-Smithsonian Center for Astrophysics’ Dr. Jonathan McDowell — are as follows:

• 4,432 are in orbit
• 4,397 in working order
• 3,767 are operational

Watch the launch