With an early morning crackling rumble and majestic display of rocket science, a SpaceX Falcon 9 zoomed away from Vandenberg Air Force Base on Friday morning, carrying the final group of satellites for a massive global telecommunications constellation.
The epic eighth launch for the Iridium Next satellite constellation lifted off at 7:31 a.m., causing people on their way to work to pull over for a glimpse of the 229-foot-tall booster as it punched through slightly cloudy skies over the Central Coast.
The launch was weeks later than Iridium Next or SpaceX expected, due to mechanical and weather problems. But the delays didn’t dim the obvious excitement about the completion of $3 billion communications system — 75 new satellites replacing an aging system that first launched two decades ago.
“There are few words to describe what it feels like to complete a vision started many years ago when I joined the company and what it means for Iridium and our future,” said Iridium CEO Matt Desch in a post-launch statement. “Our gratitude to SpaceX for helping bring this new generation of satellites to orbit, so flawlessly every time is beyond words.
“However, for Iridium, we’re not quite across the finish line yet, as there is still some work to do to put these satellites into operation. Once that’s complete, our future will be in place. I’m just incredibly proud of our team right now.”
The replacement program is considered one of the largest “tech upgrades” in space history. All of the new satellites, weighing almost 1,900 pounds each, were launched from Vandenberg in a rapid replacement pace starting Jan. 14, 2017, and ending Friday.
“The process of replacing the satellites one by one in a constellation of this size and scale has never been completed before,” SpaceX noted.
Friday’s final launch came more than 20 years after the first incarnation of the Iridium constellation began its orbital history. That first network involved 75 satellites launched between 1997 and 2002 from Vandenberg.
This time around, 81 satellites were built, with 75 successfully launched. Nine of the satellites launched will serve as in-orbit spares, and the remaining six will be ground spares.
The final satellites were deployed successfully about one hour and 12 minutes following their departure from Vandenberg.
Built by Thales Alenia Space, the satellites have a lifespan of about 15 years, and they’ll orbit about 480 miles above Earth. Iridium Next is the only satellite communications network that spans the entire globe, company officials noted.
One of the most highly anticipated services that will come once all the Iridium Next satellites are checked out and working is the AireonSM system, which will allow “truly global aircraft surveillance and tracking,” with real-time visibility for air traffic controllers and airlines planet-wide for the first time, Mr. Desch said.
Iridium satellites will also be used as satellite communications for The Ocean Cleanup, a nonprofit organization deploying advanced technologies to rid the world’s oceans of plastic, including what’s called the “Great Pacific Garbage Patch.”
Friday’s launch also involved the reuse of a Falcon 9 first stage. This mission’s first booster stage was previously used during the Telstar 18 VANTAGE mission last September, according to SpaceX.
Following Friday’s stage separation, the booster was programmed to fly back and land on a drone ship called “Just Read the Instructions” floating in the Pacific Ocean a few hundred miles offshore of Vandenberg. The booster landed successfully.
Since the Iridium Next satellites began launching, the older constellation elements have been undergoing a one-for-one replacement — new satellites for old — achieved through a highly choreographed in-space maneuver known as a “slot swap.” The older satellites are put into a lower orbit, with some re-entering the atmosphere and burning up.
As a kind of pop culture crescendo to the mission, Iridium created a special playlist on the music app called Spotify, with “fairly diverse” suggestions by fans, all tuned to coincide with key points in the countdown. During the launch countdown, Iridium tweeted the reasoning behind particular song choices.
Every element, officials said, “the timing, the words, the irony — has all been specifically designed to create a unique viewing and listening experience.”
The eclectic list started off with “The Greatest Show” from the film “The Greatest Showman,” and included “Glorious” by Macklemore; “U Can’t Touch This,” by MC Hammer; “Get up Offa That Thing,” by James Brown; “Rise Up” by Andra Day; and “My Way” by Frank Sinatra. The final song was “No scrubs” by TLC.