Following up: reusability, B612, satellite servicing
by Jeff Foust
|“I gave it sort of a 40 to 50 percent chance of working,” he said of the landing test. “I was actually pleasantly surprised by the fact that the legs deployed and landed… That’s a better outcome than I had expected.”|
Musk didn’t release any photos or video of the landing at the press conference, although he said the company was working to clean up some video it did have from the stage for later release. Last week, as promised, SpaceX did release the video, but even the “repaired” version was very garbled. In one fleeting instant of clarity, the video shows the landing legs extended and a rocket engine firing as the stage descended into choppy waters. The company has offered the raw footage to anyone interested in making their own effort to improve the video quality.
Even though SpaceX didn’t recover the stage itself, the data that indicated it landed in the ocean vertically and under power was a pleasant surprise even to Musk. “I gave it sort of a 40 to 50 percent chance of working,” he said of the landing test. “I was actually pleasantly surprised by the fact that the legs deployed and landed… That’s a better outcome than I had expected.”
SpaceX plans to test the landing and recovery of the first stage as soon as this Saturday, on the next Falcon 9 launch from Cape Canaveral of six ORBCOMM communications satellites. At the April 25 press conference, Musk said SpaceX would take several steps to have “a much greater probability” of recovering the stage, including securing larger boats to help in the recovery effort. The stage would also come down closer to shore on this flight, as the ORBCOMM satellites will go into a different orbit than the International Space Station-bound Dragon spacecraft.
“This is a really huge milestone for SpaceX and certainly for the space industry,” he said. “No one has ever soft-landed a liquid rocket boost stage before. This bodes very well for achieving reusability.”
SpaceX has also been performing other tests of technologies needed for reusability. Last month, SpaceX performed the first free flight of its Falcon 9R (F9R), a Falcon 9 first stage designed to take off and land vertically from the company’s test site in McGregor, Texas. The F9R is a successor to Grasshopper, a smaller vehicle that also performed vertical takeoff and landing tests. Last week, F9R flew again, this time to an altitude of 1,000 meters before making a powered landing, as shown in the video below.
At the post-launch press conference April 18, Musk said F9R flights would continue in McGregor for low-altitude tests no higher than about 3,000 meters. Higher altitude flights—to altitudes of 90 kilometers or more—will take place at Spaceport America in New Mexico, he said, under a deal the company announced with the New Mexico Spaceport Authority last year.
For the last several years, the B612 Foundation has been focused on raising awareness of the potential threat to the Earth posed by near Earth objects. Nearly two years ago, the organization announced plans to help identify potentially hazardous objects through a spacecraft mission called Sentinel, which the organization said it planned to fund philanthropically (see “A private effort to watch the skies”, The Space Review, July 2, 2012).
|“It will force people to rethink their assumptions about how often asteroid hit the Earth,” Lu said of the new B612 video.|
As B612 continues work on Sentinel, it unveiled last month a new video that it claimed showed the impact risk to the Earth was considerably greater than previously thought. The video showed 26 explosions in the upper atmosphere of the Earth between 2000 and 2013, varying in size between 1 and 600 kilotons of TNT, all detected by a global network of sensors designed to monitor atmospheric nuclear blasts.
Ed Lu, a former astronaut and current CEO of the B612 Foundation, said the purpose of the video was to raise awareness of how significant a threat asteroid impacts pose. “It will force people to rethink their assumptions about how often asteroid hit the Earth,” he said in a call with reporters on April 22 before a press conference at the Museum of Flight in Seattle to unveil the video. “There is a popular misconception that asteroid impacts are extraordinarily rare: millions of years between large asteroid impacts.” Instead, a “city killer” asteroid—one large enough to destroy a city if it made a direct hit—strikes about once per century.
Some criticized B612, though, for trying to play up the threat of asteroid impacts, noting that none of the impacts included in the video (other than the February 2013 meteor explosion over Chelyabinsk, Russia) caused any damage or injury, or was even noticed other than by the nuclear test ban sensors. “We created the video of the multi-kiloton Asteroid impacts not to scare people, but to provide a visually clear understanding and appreciation of one fact: asteroid impacts are not rare,” the foundation responded in a FAQ issued after the release of the video.
That attention, though, can’t hurt B612’s efforts to raise money for the Sentinel mission. Lu, in the media call, said work on the Sentinel mission was ongoing, with a launch now planned for 2018. “We are working towards our next major technical review, which is systems architecture approval, by the end of this year,” he said. Other recent work, he said, included building and testing a subscale prototype of the spacecraft’s infrared detector.
Lu didn’t go into details about how much money B612 has raised for Sentinel, other than it’s been enough to cover the initial stages of work on the mission. “We are a bit like a startup in Silicon Valley, if you will,” he said. “We’ve raised money in bunches to pay for technical milestones.” He said B612 needs to raise “larger amounts” over the next several years to pay for the mission, whose overall estimated cost is on the order of $500 million.
The idea of repairing and refueling satellites in orbit with robotic spacecraft has long been a compelling one to many in the space industry, but one that also faces many challenges beyond the technology needed for such applications (see “The space industry grapples with satellite servicing”, The Space Review, June 25, 2012). One of the biggest has been trying to find customers willing to be among the first to have their spacecraft serviced by such systems, something that requires satellite operators—often very risk averse when it comes to new technologies and capabilities—be willing to accept a considerable degree of technical and financial risk.
One satellite servicing venture, though, may have finally made that business breakthrough. “The market is responding,” said Bryan McGuirk, chief operating office of ViviSat, a joint venture of ATK and satellite communications company U.S. Space, during a panel on satellite servicing at the Satellite 2014 conference in Washington in March. ViviSat has developed a concept called the Mission Extension Vehicle (MEV) that attaches to a satellite and takes over the attitude control and propulsion needs of that satellite, extending its life or allowing it to be moved to a different orbit.
|“There will be a sea change when one company gets up there and starts operating an on-orbit servicing business,” predicts Wingo.|
“Today, we have three MEVs booked with clients, and we have a number of clients vying for that fourth [MEV] slot,” he said. Once they book the fourth MEV customer, he said, ViviSat plans to wrap up its financing and move ahead with vehicle development, which he said he expects to take place later this year. The MEVs would be launched two at a time on a vehicle like SpaceX’s Falcon 9, with the first pair planned for launch by late this decade.
While the MEV concept is fairly straightforward, McGuirk said ViviSat is looking to build upon that initial satellite life extension technology in later phases. Future versions of the MEV, he said, could repair or directly refuel satellites, and later do more full-fledged “space logistics” activities.
While ViviSat plans to start at a fairly low level of sophistication in satellite servicing, extending the operational lifetimes of satellites without making repairs or other changes to them, another satellite servicing venture is taking an even simpler approach. “In order for on-orbit servicing to work, we have to further simplify,” said Dennis Wingo, CEO and founder of Skycorp. Wingo is a veteran of satellite servicing efforts, having previously been one of the principals of Orbital Recovery Corporation, a venture in the early 2000s that also sought to provide satellite life-extension services.
Skycorp, Wingo said, is taking a simpler approach than extending the lives of satellites. Instead, he envisions a servicing spacecraft that attaches to satellite in geostationary orbit that has exhausted all of its onboard propellant, and moves that satellite into a “graveyard” orbit several hundred kilometers above GEO. Spacecraft today have to perform this “end-of-life” maneuver using their onboard propellant that, if instead used for normal orbit stationkeeping, would last for up to six months.
“We don’t have to dock with you and keep your attitude control the same as before, which is the biggest problem we had in the business,” Wingo said of Skycorp’s approach, since the satellite is no longer operating. Such a service would be “very simple, very low risk” and cost a “low fraction” of the revenue that the spacecraft would generate from that additional four to six months of operations.
“This is what we’re looking at as a practical means in the very near term to move forward” in satellite servicing, Wingo said. His company is working with NASA to fly the servicing spacecraft to the ISS on commercial cargo resupply spacecraft, testing the spacecraft at the station before deploying the servicing spacecraft to GEO. “Right now, what we’re doing is signing up customers in the GEO comsat business,” he said, with plans to begin service by the end of 2016.
One thing that many companies in the satellite servicing industry agree on is that, once any one of these systems enters service, they will soon thereafter start attracting customers who previously were in a wait-and-see mode regarding the technology. “There is a predilection to drop the bird in the ocean and just get a new one” if there’s a problem with a satellite after launch, such as being inserted into the wrong orbit, Wingo said. “There will be a sea change when one company gets up there and starts operating an on-orbit servicing business.”