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Round and Round They Go
Space is becoming
more crowded. On December 3, a Falcon 9 rocket made by SpaceX thundered into the
sky. On board were 64 small satellites, more than any American company had launched
before in one go. They have a variety of uses, from space-based- radar to the monitoring
of radio-frequency- emissions.
These objects
are part of the latest breed of low-Earth-orbit (LEO) satellites. This launch is
just taste of what is planned. SpaceX and OneWeb, a communications firm, plan to
launch satellites in their thousands, not hundreds. The pair are set to double the
total number of satellites in orbit by 2027.
That promises
to change things dramatically on Earth. LEO satellites can bring internet connectivity
to places where it is still unavailable or unaffordable. This will also be a lasting
source of new demand for the space economy. Morgan Stanley, a bank, projects that
the space industry will grow from $350 billion in 2016 to more than $1. I trillion
by 2040. New internet satellites will account for a half this increase.
For that to
happen, however, three worries must be overcome. Debris(碎片)is the most familiar concern.
As long ago as 1978, Donald Kessler, a scientist at NASA, proposed situation in
which, when enough satellites were packed into low-Earth orbits, any collision could
cause a chain reaction which would eventually destroy all space craft in its orbital
plane(平面). The syndrome which bears Mr. Kessler's name weighs
heavily on the minds of executives at the new satellite firms. Debris could cause
entire tracts(广阔的一片) of space to be unusable for decades.
Solutions exist.
One is to grab malfunction satellites and pull them down into Earth's atmosphere.
Another is to monitor space more intensively for debris; a US Air Force programme
called Space Fence is due to start in 2019. But technology is only part of the answer.
Rules are needed to govern the safe disposal(清除) of old satellites from low-Earth orbit. The United States'
Federal Communications Commission is revising its regulations with this in mind.
Other countries should follow suit.
Cyber-security
is a second, long-standing worry. Hackers could take control of a satellite and
seal intellectual property, redirect data flows or cause a collision. The satellite
industry has been slow to respond to such concerns. But as more of the world's population
comes to rely on the infrastructure of space for access to the internet, the need
for action intensifies.
The third issue
follows from the first two. If a simple mistake or a cyber-attack can cause a chain
reaction which wipes out hundreds of billions of dollars of investment, who is liable?
Underwriters(保险商) are
studying the plans of firms that wish to operate large numbers of satellites. But
there is a long way to go before the risks are well understood, let alone priced.
As space becomes
more commercialized mind-bending prospects open up: packages moved across the planet
in minutes by rocket rather than by plane, equipment sent to other small planets,
passengers launched into orbit and beyond. All that and more may come, one day.
But such activities would raise the same questions as LEO satellites do. They must
be answered before the space economy can truly develop.