A SpaceX Falcon 9 rocket overcame a rare in-flight engine failure soon after launch from Florida’s Space Coast Wednesday to place 60 satellites in orbit for the company’s Starlink Internet network.
One of the rocket’s nine first stage engines shut down prematurely around 2 minutes, 22 seconds, after liftoff from pad 39A at NASA’s Kennedy Space Center in Florida, an event visible in a view from a camera streaming live video from the Falcon 9 as it climbed into the upper atmosphere.
Elon Musk, SpaceX’s founder and CEO, confirmed in a tweet that the Falcon 9 experienced an “early engine shutdown on ascent, but it didn’t affect orbit insertion.”
The rocket’s other Merlin engines fired a little longer to compensate for the loss of thrust. The rest of the Falcon 9’s climb into orbit appeared to go according to plan, and the upper stage deployed the 60 Starlink satellites into orbit around 15 minutes after liftoff.
“Shows value of having 9 engines!” Musk wrote on Twitter.
The first stage missed a landing attempt on SpaceX’s drone ship parked in the Atlantic Ocean northeast of Cape Canaveral, the second time SpaceX has missed a rocket landing in the company’s last three missions. It was not immediately clear whether the engine shutdown on ascent affected the recovery attempt.
There are nine kerosene-fueled Merlin 1D engines on the Falcon 9’s first stage, each generating 190,000 pounds of thrust at sea level when firing at full power. The Falcon 9 is designed to persevere through a booster engine failure and still deliver its payload to orbit.
The in-flight engine failure on Wednesday’s launch marked the second time a Merlin engine has prematurely shut down on a Falcon 9 flight.
In October 2012, a Merlin 1C engine — a predecessor to the Merlin 1D — failed during the launch of a Dragon supply ship on the way to the International Space Station. The Falcon 9 was still able to deliver the Dragon spacecraft into orbit, but the failure resulted in the loss of an Orbcomm data relay satellite riding as a secondary payload.
Musk promised a “thorough investigation” of Wednesday’s early engine shutdown before the next Falcon 9 launch, and it was not immediately clear whether the inquiry might prompt launch delays.
The first stage flown on Monday’s mission was making its fifth trip to space, after flawless performance on four previous missions since 2018. It was the first time SpaceX has launched a Falcon 9 booster on a fifth flight.
The launch was previously scheduled for Sunday, but computers ordered a last-second abort after ignition of the rocket’s Merlin main engines. Musk tweeted that the launch attempt was aborted due to “slightly high power” detected in the Falcon 9’s propulsion system, adding that the event was “possible, but not obviously, related to today.”
Elon Musk, SpaceX’s founder and CEO, confirms one of the Falcon 9’s first stage engines shut down prematurely during today’s launch.
Although the rocket achieved the planned orbit, Musk says a thorough investigation is needed before the next mission. https://t.co/jYtac6xrlZ pic.twitter.com/YsvHGinGrD
— Spaceflight Now (@SpaceflightNow) March 18, 2020
“This vehicle has seen a lot of wear, so today isn’t a big surprise,” Musk tweeted. “Life leader rockets are used only for internal missions. Won’t risk non-SpaceX satellites.”
SpaceX says Falcon 9 boosters are designed for 10 missions without major work, although technicians routinely perform inspections and some refurbishment on the vehicles between flights.
The 229-foot-tall (70-meter) Falcon 9 rocket took off at 8:16:39 a.m. EDT (1216:39 GMT) Wednesday from pad 39A at the Florida spaceport, then turned northeast to soar into space over the Atlantic Ocean.
The Falcon 9’s first stage continued firing more than around 15 seconds after the engine failure, then separated to allow the rocket’s second stage to ignite its single Merlin engine to accelerate into orbit with the 60 Starlink satellites.
The bulbous aerodynamic shroud on the nose of the Falcon 9 rocket jettisoned moments later. Like the first stage, the two halves of the clamshell-like fairing were recycled from a previous mission.
SpaceX later confirmed the two fairing halves descended to parachute-assisted water landings in the Atlantic Ocean, where two recovery ships were on station to retrieve the parts and return them to port.
The Falcon 9’s booster reignited its engines for an entry burn to begin slowing down for landing on SpaceX’s football field-sized landing platform, but the video feed from the first stage cut off soon after the maneuver. SpaceX later confirmed the booster was unable to land on the drone ship.
A Falcon 9 first stage also missed landing on the drone ship after a Feb. 17 launch, but the booster on a March 6 launch made a successful onshore landing at Cape Canaveral Air Force Station.
SpaceX is the only company that currently recovers and reuses orbital-class rocket boosters.
While recovering the booster helps reduce costs and maintain a rapid launch cadence, the first stage landing is always a secondary objective on SpaceX missions.
The rocket’s upper stage shut down its engine around nine minutes after liftoff Wednesday, then fired thrusters to enter a spin before releasing the 60 flat-panel Starlink satellites. Live video beamed back to ground controllers from the Falcon 9 showed the Starlink payloads flying away from the rocket as the vehicle soared over the North Atlantic Ocean.
Sixty Starlink broadband relay satellites have deployed from SpaceX’s Falcon 9 rocket in orbit. With this launch, SpaceX has launched 360 Starlink stations since last May. https://t.co/jYtac6xrlZ pic.twitter.com/KhajN01rOU
— Spaceflight Now (@SpaceflightNow) March 18, 2020
The 60 Starlink spacecraft were to be released in an elliptical, or egg-shaped, transfer orbit ranging between 130 miles (210 kilometers) and 227 miles (366 kilometers) above Earth, with an inclination of 53 degrees to the equator.
Each of the quarter-ton Starlink satellites was expected to unfurl a solar array wing and activate a krypton ion propulsion drive to begin climbing to an operational orbit 341 miles (550 kilometers) in altitude.
The Starlink network is designed to beam Internet signals to most of the world’s population, targeting hard-to-reach consumers and users on the go. With Wednesday’s launch, SpaceX has added 360 satellites to the Starlink fleet since beginning dedicated missions last May.
SpaceX has become a leader in the commercial launch market with its Falcon 9 and Falcon Heavy rockets, thanks in large part to the company’s ability to cut the cost of access to space. The company is developing a pair of next-generation vehicles called the Starship and the Super Heavy booster to replace the Falcon rocket family.
Musk has said revenue from SpaceX’s business, including launch contracts and Starlink services, will help fund development of the Starship and other future technology needed to carry people to Mars and other planetary destinations.
“The whole purpose of SpaceX is really to help make life multi-planetary, but the revenue potential of launching satellites, servicing the space station and whatnot, that taps out about $3 billion a year,” Musk said March 9 in a talk at the Satellite 2020 conference in Washington. “But I think providing broadband is more like an order of magnitude beyond that, probably $30 billion a year as a rough approximation. And we’re still probably below 5 percent (market share) at that point.”
Musk said the Starlink network will reach the “hardest to serve” Internet customers, and will not be a major threat to established telecom operators.
“It’s not like Starlink is some real threat to teclos,” he said.
The first phase of the Starlink network will include more than 1,500 satellites — including spares — orbiting 341 miles above Earth on tracks inclined 53 degrees to the equator. But SpaceX has regulatory authority from the Federal Communications Commission to operate up to 12,000 communications and data relay spacecraft.
“5G is great for high-density situations like being here in D.C. or New York, San Francisco, that kind of thing,” Musk said. “But it’s actually not great for the countryside. For rural areas, it’s not great. You need range. So any kind of sparse environment, 5G is really not well-suited, but it’s great for dense city situations.
“So Starlink will effectively service the 3 or 4 percent hardest to reach customers for telcos, or people who simply have no connectivity right now, or the connectivity is really bad,” Musk said. “So I think it will be actually helpful and take a significant load off the traditional telcos.”
The U.S. military could also be a major customer for Starlink services.
SpaceX has not publicized connectivity speeds or prices for consumer-grade connectivity through the Starlink network. But Musk gate prospective customers a taste of what they could expect.
“It will be very low latency, and we’re targeting latency below 20 milliseconds, so somebody could play a fast response video game at a competitive level,” he said. “That’s the threshold for latency. And bandwidth? The bandwidth is a very complex question. Let’s just say somebody will be able to watch high-definition movies, play video games, and do all the things they want to do without noticing speed.”
Musk said user ground terminals will “look like a UFO on a stick,” and the first version of the Starlink ground antenna will have actuators to point the transmitter and receiver.
“It’s very important that you don’t need a specialist to install,” Musk said. “The goal is that (on) the instructions on the box, there are just two instructions, and they can be done in either order: Point at sky and plug in.”
Many astronomers are worried that the launch of thousands of satellites, such as those planned by SpaceX and competitors like OneWeb and Amazon, will impact observations of the night sky.
SpaceX’s Starlink satellites are brighter than expected, particularly soon after a launch when the spacecraft are clumped together in clusters at lower altitudes. Reflective surfaces on the satellites glint sunlight back to Earth’s surface near dawn and dusk.
The European Southern Observatory reported March 5 that its Very Large Telescope and future Extremely Large Telescope in Chile will be ‘moderately affected’ by the satellite constellations under development. About 3 percent of long exposures from the telescopes could be ruined at twilight, the scientists concluded in a study accepted for publication in the scientific journal Astronomy & Astrophysics.
But other facilities may not be so fortunate.
“The study also finds that the greatest impact could be on wide-field surveys, in particular those done with large telescopes,” ESO said in a statement. “For example, up to 30 percent to 50 percent of exposures with the U.S. National Science Foundation’s Vera C. Rubin Observatory … would be ‘severely affected,’ depending on the time of year, the time of night, and the simplifying assumptions of the study.
“Mitigation techniques that could be applied on ESO telescopes would not work for this observatory although other strategies are being actively explored,” ESO said.
Musk dismissed those concerns March 9.
“I’m confident that we will not cause impact whatsoever in astronomical discoveries,” he said. “Zero. That’s my prediction. We’ll take corrective action if it’s above zero.
“When the satellites are first launched, they’re tumbling a little bit, so they’re going to glint because they haven’t stabilized. And they are raising their orbits, so they’re lower than you’d expect, and they reflect in ways that is not the case when they’re on orbit.”
SpaceX and OneWeb are working with scientists to mitigate the effects of satellite constellations on astronomical observations.
“So we’re running a bunch of experiments to, for example, paint the phased array antenna black instead of white,” Musk said. “And we’re working on a sunshade because there are certain angles if the sun get just right and there’s not, like, a little sunshade — we’re not talking about a lot here — then you can get a reflection. So we’re launching sunshade, changing the color of the satellites, and otherwise minimizing the potential for any impact.”
SpaceX said last month it was considering spinning off the Starlink business into a separate company, and potentially launch a public stock offering in the project, in the next several years.
Musk said March 9 that SpaceX is focused on making Starlink successful first.
“We’re thinking about that zero,” he said. “We need to make the thing work.”
Guess how many LEO (low Earth orbit) constellations didn’t go bankrupt? Zero. Iridium’s doing OK (now), but Iridium 1 went bankrupt. Orbcomm went bankrupt. Globalstar, bankrupt. Teledesic, bankrupt.”
Musk said there’s room for other companies in the market to provide Internet services from space, and SpaceX is happy to launch satellites for competitors. SES, a longtime SpaceX customer, announced last year it would launch seven high-power broadband satellites for its O3b mPower network on two Falcon 9 rocket flights.
“If you want to launch a constellation on SpaceX, that sounds good to me,” he said. “The world seems to have an insatiable appetite for bandwidth … We don’t think Starlink is going to destroy all other satellites, or something like that.”
The next launch on SpaceX’s schedule is slated for no earlier than March 30 from pad 40 at Cape Canaveral. A Falcon 9 rocket is being readied to carry Argentina’s SAOCOM 1B radar observation satellite into a polar sun-synchronous orbit, flying on a southerly trajectory just offshore roughly parallel with Florida’s East Coast.
The last time Cape Canaveral was the departure point for mission into a polar orbit was in 1960.
Another Falcon 9 launch with Starlink satellites is scheduled from pad 40 in April, and a U.S. military GPS navigation satellite is set to take off on a Falcon 9 rocket April 29, also from pad 40.
SpaceX’s first mission with astronauts could launch as soon as May from pad 39A at the Kennedy Space Center. NASA astronauts Doug Hurley and Bob Behnken are training for a test flight to the International Space Station aboard SpaceX’s Crew Dragon spaceship.
That flight will be the first human space mission to launch into orbit from U.S. soil since the retirement of the space shuttle in 2011.
But launch dates hinge on numerous factors, including the growing coronavirus pandemic, which has prompted NASA to mandate telework for non-essential employees at all the agency’s facilities, including the Kennedy Space Center.
NASA Administrator elevated the agency to Stage 3 of NASA’s Response Framework late Tuesday, triggering new limits on travel and access to NASA centers. But critical work needed to maintain safety, security, launch dates and mission operations continues.
In Stage 4 of the Response Framework, NASA centers would effectively be shut down entirely, except for workers required to protect “life and critical infrastructure.”
There’s some added uncertainty about SpaceX’s upcoming launch schedule as engineers begin their investigation into the early engine shutdown on Wednesday’s mission.
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