MAY 2018 | 5280 | (^111)
ATTENDEES OF THE INSTITUTE OF NAVIGATION’S Precise Time and Time Interval annual
meeting in 2016 were just inishing up their irst day of discussions in Monterey,
California, on January 25 when the Boulder contingent’s cell phones started going
of. hese representatives from the National Institute of Standard and Time (NIST)
were connected to a national alarm system set to send near-constant text alerts when
UTC had run amok. Beginning at 5:10 p.m. Paciic Standard Time, the NIST staf
members’ cell phones squawked, beeped, hooted, and buzzed every 10 minutes with
alarm messages. Something was wrong.
hings had started to go askew hours before at Schriever Air Force Base, where,
at 4 p.m., the 2nd Space Operations Squadron (2SOPS) team—the small group in
charge of operating the country’s GPS constellation—had taken one of its oldest sat-
ellites out of service. It was a planned decommissioning: Space Vehicle 23 had been
launched in 1990, the irst in a group of 19 just like it. But when the 2SOPS team
pulled the satellite’s proverbial plug, a system glitch resulted in a timing error of 13.7
millionths of a second—about the time it takes for a hummingbird to beat its wings
once—in roughly half of the United States’ GPS satellites.
he timing malfunction lasted just a few hours before it was recognized and
addressed, but it took more than a day in some places to restore the systems afected
by the 13.7-microsecond hiccup. Cell phone companies experienced service inter-
ruptions; irst responder networks across the nation reported faults; and in Puerto
Rico, the Arecibo Observatory—one of the world’s largest radio telescopes, which,
among other things, tracks asteroids on potential collision courses with Earth—
shut down for at least part of a day. None of these disruptions qualiied as critical
failures, though, and in some ways, that was comforting. he short-term glitch had
jarred some U.S. infrastructure, but the world hadn’t ended. hen again, the NIST
team had recognized the error and the Air Force had corrected it within hours.
What happens if GPS fails for longer than that?
“We’re not really sure, because the systems that rely on it are so complex,” Goward
says. Although the National Security Telecommunications Advisory Committee has
suggested that the United States has enough backup systems in place to mitigate the
efects of clock drift from prolonged GPS outages for approximately 30 days, other
agencies aren’t so conident. he Department of Homeland Security itself has called
GPS “a single point of failure for critical infrastructure.” And that’s precisely why some
U.S. adversaries have targeted it.
WHEN THE TRUMP administration revealed its 2019 budget request for the Depart-
ment of Defense, the Air Force’s proposed unclassiied space budget got a lot fatter:
around eight percent bigger, or about $8 billion more. hat’s because, in part, as Air
Force budget director Major General John Pletcher noted to reporters at a February
Pentagon brieing, “We are in a more dangerous security environment than we have
seen in generations. Global trends are eroding our advantage in air and space.”
In the case of space, at least, it seems fair to interpret “global trends” as largely
Russia and China, both of which have built up their space capabilities in recent years.
Like the United States, Russia has its own GNSS constellation, GLONASS. China’s
system (BeiDou)—as well as Europe’s (Galileo)—are already
you’ll ind mostly communication satellites, includ-
ing those for military users and also commercial
units for companies like Sirius XM and DirecTV.
he reason for this is that satellites in GEO move
at the same rate as the Earth, so those satellites are
always looking at the same place on the ground.
hat ensures DirecTV has the ability to broadcast
to the same audience, and it also allows the U.S.
military to have a reliable channel over which to
communicate and share data.
hink of GPS satellites in MEO like buoys in
space, constantly sending out signals that include
the devices’ times and positions. housands of
miles below, receivers, like your smartphone, pick
up the signals and determine precise locations by
using the information—and diferences in the
time that information comes in—from each satel-
lite. To ensure this exactness, each GPS satellite is
equipped with super-precise atomic clocks. he
United States Naval Observatory uses those timing
systems to provide Coordinated
Universal Time (UTC), the stan-
dard America uses for everything
from stock market transactions to
electrical power grid management
to transmitting police and other
emergency services communica-
tions. Why is a timing standard so
important? Because those complex
systems pass data across networks
that all have to be synchronized.
“hose networks don’t send long
messages to each other,” says
Dana A. Goward, president of the
Resilient Navigation and Tim-
ing Foundation and a member of
President Donald Trump’s National Space-Based
Position, Navigation, and Timing Advisory Board.
“hey send strings of data, and they have to all know
exactly what time it is so they can time-stamp the
little packages of data and make sense of them.”
Should GPS go oine for a period of time,
those systems—cell towers, ATMs, electrical
grids—become dependent upon their own built-
in backup clocks, some of which are good, some
of which are not so good, and some of which are
nonexistent. he longer GPS is of the mark in
terms of timing, the less synchronized these com-
plex systems become, a phenomenon known as
“clock drift.” Essentially, the traic cops for our
digital world could lose the ability to talk to one
another. Should that happen, all modes of transpor-
tation could slow down, Goward cautions, noting
that everything from traic signals to airplanes
to shipping ports relies on the timing function of
GPS. here could be power outages. ATMs could
become inaccessible. Cell service could become
spotty. It doesn’t take a lot of imagination to see the
dark path down which the loss of that technology
and human nature could take us. In fact, a couple of
years ago, we got an early glimpse. CONTINUED ON PAGE 241
SPACE GAMES
“IT’S NOT JUST ABOUT THE MILITARY.
IN SOME WAYS, WITH GPS, WHAT’S AT
STAKE IS A NATIONAL TREASURE.”
—Lieutenant Colonel Anibal Rodriguez
grace
(Grace)
#1