SpaceX launches 10 more Iridium NEXT satellites
A SpaceX Falcon 9 rocket streaked away from California early Friday, boosting the fifth set of 10 Iridium NEXT relay stations into orbit, the latest step in the satellite telephone provider's push to complete a globe-spanning constellation of next-generation spacecraft.
Perched atop pad 4E at Vandenberg Air Force Base northwest of Los Angeles, the Falcon 9's previously flown first stage engines thundered to life at 7:13:51 a.m. PDT (GMT-8), quickly pushing the slender 129-foot-tall rocket away on a southerly trajectory over the Pacific Ocean.
While SpaceX frequently recovers booster stages after launch, the company said it did not intend to salvage the older-generation booster used Friday. Engineers did, however, plan to attempt recovery of the rocket's nose cone fairing using a custom-built ship named "Mr. Steven."
But getting the 10-satellite payload into orbit was the primary objective of the mission, the fifth batch in a $3 billion 81-satellite constellation intended to replace Iridium's aging fleet of low-Earth-orbit mobile voice and data relay stations.
SpaceX normally provides live video from a second stage rocket cam showing satellite deployment, carried out about an hour after launch, but the company ended its launch webcast early because of "restrictions" from the National Oceanic and Atmospheric Administration. Sources later said the cameras could be considered "remote sensing" instruments requiring a license, although SpaceX uses them solely for engineering views of the rocket and payload.
In any case, 66 of the 1,896-pound satellites operating in six orbital planes are required to complete the Iridium NEXT network. The company plans to eventually launch 15 in-orbit spares, using SpaceX to put 75 of the 81 planned satellites into orbit at a cost of more than $500 million.
SpaceX successfully launched the first 10 Iridium NEXT spacecraft on Jan. 14, 2017, a second set the following June, 10 more last October and a fourth set last December.
"We really are focused on completing our Iridium Next constellation this year," Iridium CEO Matt Desch told Spaceflight Now. "I'd like it completed in the third quarter if possible.
"What I'm really pleased with is that SpaceX has stepped up this year. Unlike last year, where we might have been waiting for SpaceX, I think this year I'm trying to make sure my suppliers are delivering fast enough to go as quickly as possible."
SpaceX's sixth Iridium NEXT launch, carrying satellites 51 through 55, is targeted for around mid May, using another previously flown booster for a flight shared by a NASA payload. Two more Falcon 9/Iridium NEXT flights are expected later this year.
The new spacecraft feature a phased-array antenna that can generate 48 beams over a footprint 3,000 miles across. Each satellite also is equipped with high-speed links to ground stations and the required satellite-to-satellite cross links that allow users anywhere in the world to communicate cell phone fashion.
"The new satellites are a lot more powerful, a lot more processing power, they've got a lot more memory, a lot more capacity, they actually expand our ability to support customers," Desch said in an earlier interview with CBS News. And, he added, "they're easier to operate."
The NEXT-series satellites also carry circuitry provided by Harris Corp. to track ships at sea on a minute-by-minute basis and another Harris-built device, provided by a multi-agency consortium known as Aireon, that eventually will track aircraft anywhere in the world.
"They are doing a lot of trials and demonstrations with all their customers, but you really can't provide air traffic control services if you don't have 100 percent coverage, so they need all 66 satellites in operation for that," Desch told Spaceflight Now. "They're expected to turn on their service later this year as the network goes live ... and they'll start providing second-by-second coverage for air traffic controllers."
Iridium engineers are working to ensure a smooth transition from the older satellites to the new Iridium NEXT relay stations, making sure each new satellite is checked out, operational and in the proper orbital slot before its predecessor is retired and dropped out of orbit.
One lamented by-product of the transition is the eventual loss of so-called Iridium flares.
The older satellites, built by Lockheed Martin, featured a design that caused sunlight to predictably flare up, producing brilliant flashes easily visible from the ground. Amateur satellite observers made a hobby of spotting such flares using predictions generated by smartphone apps.
The Iridium NEXT satellites, designed by the European aerospace giant Thales Alenia Space and built by Orbital ATK in Arizona, feature a different design that will not routinely result in flares.
"It's a little different for me because it's our network, but I found it to be almost an emotional experience the first time I saw one," Desch said. "People love seeing the International Space Station for the same reason. ... It's hundreds of miles away, and yet you can still see it gleaming."
With the era of Iridium flares slowly drawing to a close, "I highly encourage people to go out (and see one)," he said. "I think it's really cool, a great party trick for friends and a great way to win a drink at the right time at a bar."
With the Iridium launch out of the way, SpaceX will turn its attention to the Cape Canaveral Air Force Station where engineers are readying another previously flown Falcon 9 for launch Monday to put a space station-bound Dragon cargo ship into orbit for a two-day rendezvous with the lab complex.
