SpaceX successfully put another 60 Starlink satellite into orbit today, November 11. The flight marks the first time a Falcon 9 first stage has flown for the fourth time and the first reuse of the payload fairing, as well as the heaviest payload to date lofted into orbit by the Falcon 9 rocket. Today’s launch gives SpaceX Starlink a total of 120 or satellites in orbit – but not all of them are operational and are in two different hardware configurations.
The launch took place on time at 9:56 AM ET from Space Launch Complex 40 (SLC-40) at Cape Canaveral Air Force Station, Florida. SpaceX has emphasized reusing launch hardware is key to driving down the cost of getting to space with today’s flight demonstrating a successful flight and recovery of a Falcon 9 first stage. Company officials and today’s webcast said the Falcon 9 first stage can fly up to 10 times without major overhaul, with Musk once suggesting a first stage may be able to fly up to 100 times. The payload fairing used today was previously flown on the second Falcon Heavy launch, but no attempts were made to recover from this mission it due to high sea conditions.
Satellites for today’s launch were deployed at an altitude of 280 kilometers and will move up to an altitude of 350 kilometers if they all check out OK. Prior to launch, SpaceX said one satellite wasn’t looking healthy enough to do an orbit raise, which would put the count at 59 functional satellites added to the 56 functional satellites launched in May.
Today’s batch of satellites added three features, according to the SpaceX webcast launch narrative. Upgrades double the number of steered antenna beams over the first batch of satellites launched in May, along with a 400 percent improvement in data throughput and the addition of Ka-band support. Optical cross links, a key component of the initial system design, aren’t expected to be introduced on satellites until mid to late 2020, according to public statements by SpaceX President Gwynne Shotwell.
Starlink service is expected to be available in the Northern U.S. and Canada after six launches, with global coverage of the populated world achieved after 24 launches. Exactly what the speeds and latencies of service will be available is unknown at this point in time, since users will have to cope with Ku-band only availability from 56 satellites and there’s no clear statement on how satellites will use ground stations to relay data between other satellites and orbital planes until optical cross-link hardware is introduced. SpaceX boasted an in-air demonstration delivering over 600 Mbps to an Air Force plane in flight, but it isn’t known if this is representative of throughput with multiple users in the service area of one or more satellites.
In May, SpaceX said it would conduct anywhere from 4 to 6 more Starlink launches by the end of the year, but there’s little evidence that the company will hit that mark. Initial indications were SpaceX would conduct at least one Starlink launch in October, but it didn’t happen. Based upon past launch tempo, it is possible SpaceX could conduct one more launch if it has enough satellites ready to go. SpaceX needs to conduct a supply launch for NASA currently scheduled for December 4 and is scheduled to conduct a commercial satellite launch on December 15. In theory, SpaceX could wedge in another launch by December 31.