another guest post from George Leopold:
What follows goes beyond the realm of blue-sky thinking, extending to what might be called Star Trek-thinking. Nevertheless, we need to start reexamining how we design, build and launch weather satellites with an eye to reducing costs while improving the resolution that underpins weather services.
The primary focus of government R&D efforts focuses on greatly reducing the cost of access to space and fundamentally changing the way we manufacturer and launch military and civilian satellites. The latter approach includes a high-risk, high-payoff initiative at the Defense Advanced Research Projects Agency, or DARPA, to assemble and service satellites in orbit!
“We want the ability to change the paradigm and shift the cost of building satellites,” says DARPA’s Pamela Melroy.
Space technology is being driven by the same economic factors that have given us fighter jets that cost $50 million a copy. If this trend continues, according to a set of aphorisms known as Augustine’s Laws, named for the former Lockheed Martin CEO Norman Augustine, the Air Force will be able to buy exactly one new fighter aircraft by, say, 2020.
“Even if you really are starting with drawings and you know the system very well, building a satellite can take two to five years and then two years to launch. So there’s no agility and flexibility currently in our launch capability,” warns Melroy, a former space shuttle commander who now helps oversee space systems development in DARPA’s Tactical Technology Office.
While the research agency focuses on military satellite technology, Melroy’s cost growth example remains relevant to Earth observation. In the early 1990s, the first-generation Global Positioning System cost about $43 million to build and $55 million to launch. The desire to extend the lifetime of satellites requires greater redundancy. With that comes complexity and greater cost. Melroy estimates that GPS III satellites now in development will cost $500 million a pop with launch costs reaching more than $300 million per launch.
And lest we think weather satellite launches are routine, reports out of China indicate that a $250 million Earth observation satellite developed by Brazil and China failed to reach orbit on Dec. 9.
Along with seeding the market for commercial development of key components like re-useable rockets, DARPA also is touting a radically new approach to building and maintaining satellites in space called Phoenix Satellite Servicing.
“The fundamental goal is to change how satellites are built,” Melroy says. “We’d like to shift to on-orbit assembly and servicing. That’s going to unable us to upgrade our satellites” to extend their lifetimes.
Phoenix also would seek to adopt commercial practices like high volume, lost cost manufacturing of modular satellite components to transform the way satellites are designed. Expensive assets like sensors could also be reused and satellites would be more modular.
Melroy argues that future satellites should adopt the architecture used for the Hubble Space Telescope, which was designed to be serviced in orbit.
Along with launching a robotic satellite servicer into orbit,
DARPA’s scheme also includes the use of modular satellites, or interchangeable “satlets.” The approach will be used in a future demonstration to try to bring a retired satellite back to life.
“Once you have that capability [to service satellites], could you not have a whole platform made of satlets that is essentially immortal because you just come in and you stick a new payload on it?” Melroy suggests.
The basic concept underpinning satlets, including the ability to operate and communicate with each other, has been demonstrated by a California satellite company called Millennium Space Systems. Separately, Millennium won an Air Force contract in March 2013 to study how military weather satellites could be “disaggregated” into more affordable constellations that could be used to plug coverage gaps.
DARPA officials acknowledge that such a radical departure from traditional satellite design and deployment remains risky. But the potential payoff is worth the risk given the stratospheric cost of satellites. Moreover, the defense agency’s role is to push the envelope to field “disruptive” technologies. After all, these are the same folks who understood in the late 1960s that computer networks might someday prove useful. The germ of that idea created what we now call the Internet.
It’s far from clear that a radical approach like Phoenix could be used for building and servicing weather satellites. Melroy acknowledges that the satellite effort would have to have a “fairly large [technology] pull” before civilian agencies would buy into the approach. She added, however, that the program expects to deliver space-qualified hardware in the next 18 months.
Perhaps then we can begin to boldly go where no satellite technology has taken us before.