The first set of larger, second-generation Starlink satellites are experiencing problems that could force SpaceX to take at least some of them out of orbit. inside that chirp On March 22, SpaceX CEO Elon Musk said there were “some issues” with the Starlink satellites launched on February 27, confirming industry speculation over the past few days that the orbits of the spacecraft have changed.

“There’s a lot of new technology in Starlink V2, so we have some issues as expected,” he wrote. “Some satellites will be removed from orbit, others will be extensively tested before ascending to altitude above the Space Station.”

The 21 satellites, known collectively as Group 6-1, began to rise in their orbits a few days after being placed in orbits at an altitude of about 370 kilometers. But after a few days the satellites stopped raising their orbits and kept their orbits at an altitude of about 380 kilometers. The International Space Station orbits at an altitude of 415 to 420 kilometers.

Beginning around March 15, orbital altitudes began to decrease at varying rates: the most gradual, but at least two steeper, drops to about 365 kilometers. All 21 satellites remained in orbit, but this unusual behavior led to speculation that there were problems with the satellites.

Musk’s tweet was the first comment by Musk or SpaceX to confirm problems with the satellites, although neither he nor the company specified what the problems were. Group 6-1 satellites are the first satellites SpaceX calls “V2 Mini” versions of Starlink satellites. They are significantly larger than the first-generation Starlink satellites SpaceX has launched more than 4,000 to date.

The spacecraft has an advanced phased array antenna and uses E-band frequencies for feedback, giving each satellite four times the bandwidth of the previous spacecraft. There are also new high-efficiency electric motors that use argon instead of krypton to keep costs down.

SpaceX hasn’t released details about the V2 Mini satellites, but a design dubbed “F9-2” in documents the company has submitted to the Federal Communications Commission as part of its second-generation Constellation implementation describes an 800-kilogram spacecraft and several sunbursts. 12.8 meters long panels. Satellites of the first generation weigh about 300 kilograms and have a single grid eight meters long.

As the name suggests, the V2 Mini spacecraft is a scaled-down version of the last V2 Starlink satellites that will weigh around 2,000 kilograms, each with 20 meters long solar panels. These spacecraft will be launched on SpaceX’s Starship, while the V2 Mini spacecraft is small enough to be launched on Falcon 9 rockets.

In December, the FCC partially approved SpaceX’s second-generation, or Gen2, Starlink series, allowing the company to launch 7,500 of its proposed 30,000 satellites into orbits between 525 and 535 kilometers. Since then, SpaceX has launched four sets of “Group 5” satellites into FCC-approved Gen2 orbits, but they look nearly identical to previous Starlink satellites. Another Group 5 launch will take place on March 24 from the Space Force Station in Cape Canaveral, Florida. The second set of V2 Mini satellites, Group 6-2, is also scheduled to launch before 30 March from Cape Canaveral, although it is unknown whether issues with orbiting V2 Mini satellites will delay this launch.