Why did SpaceX designate these satellites as Gen2 rather than Gen1?

In interviews last Spring, Elon Musk said the data throughput of the next version of Starlink satellite (Gen2) would be almost an order of magnitude greater than that of the first generation and that the new Starship rocket would be needed to launch them. Regulatory and engineering delays slowed Starship’s progress, so the Gen2 satellites Musk referred to at the time have not yet been launched.

Last Fall, SpaceX broadened the definition of Gen2 to include three configurations, designated F9-1, F9-2, and Starship. Musk was referring to the Gen2 Starship version when he described high-capacity satellites last Spring. The SpaceX Falcon rocket will launch F9-1 and F9-2 satellites, but the Starshi version will require the Starship rocket.

Last month, the FCC authorized SpaceX (PDF) to launch 7,500 Gen2 satellites operating at altitudes of 525, 530, and 535 km and inclinations of 53, 43, and 33 degrees, respectively, using frequencies in the Ku- and Ka-bands. (They had applied for authorization for 29,988 satellites but only 7,500 were approved at this time—perhaps due to concern over space debris.)

Last week, SpaceX launched 54 Gen2 F9-1 satellites and they are close, if not identical, to the earlier Gen1, version 1.5 Satellites SpaceX has been launching recently. Eric Ralph referred to them as “suspiciously similar,” and NASA confirmed that they were the same size and mass as the previously launched Gen1 version 1.5 satellites.

Why did SpaceX designate these satellites as Gen2 rather than Gen1?

Tim Farrar attributes it to SpaceX gaining a competitive advantage over potential rival Kuiper, saying, “It’s very clear that SpaceX wants to launch the first Ka-band Gen2 satellites before Kuiper’s test satellites to gain a band-splitting advantage.”

In 2018, the FCC granted SpaceX permission to use the 27.5-29.1 GHz and 29.5-30.0 GHz bands for Gen1 Earth-space transmission. Subsequently, SpaceX was authorized to use those bands for its Gen2 satellites and Kuiper was authorized to use 27.5-3,0 GHz for its satellites. The FCC rules say that SpaceX and Kuiper can agree to a spectrum-sharing rule that protects the first-round rights of SpaceX, but if they cannot agree, the first to launch a satellite capable of operating in the frequency band under consideration gets to choose which portion of the spectrum it will use when interference is detected.

A second motivation may have been the Gen2 right to orbit at a 43-degree inclination. Starlink has had insufficient capacity to serve customers in some regions and may have calculated that the 43-degree inclination would ease that congestion in relatively high-price, high-demand regions like the U. S., where Ookla has shown declining speeds tor three quarters.

Regardless, the designations Gen1 and Gen2 seem arbitrary, and we won’t see a meaningful difference between them until Gen2 F9-2 satellites are launched, and we won’t see a major difference until Starship is flying and launching Gen2 Starship satellites.

Update Feb 27, 2022:

SpaceX has posted some information about the Gen 2 F9-2 satellites. They are referring to them as “V2 Mini” satellites and say they will have four times the capacity of the Gen 1 satellites. The image shown here shows 21 satellites, presumably the number that can be launched by the current Falcon 9 rocket. As mentioned above, Elon Musk predicts the Starship satellites will be around ten times the capacity of the current satellites.

The update also lists several steps and links to documents SpaceX is taking to avoid collisions and to reduce reflected light that interferes with astronomy.

There was speculation that the first V2 Mini would be launched on February 23rd, but that launch was postponed until today and Starship is expected to attempt an orbital launch next month. I wonder whether SpaceX will launch more Gen 2 F9-1 satellites—the answer probably depends upon the ability to ramp up manufacturing of the Minis.