Cosmic Rays? No Problem!
by Allen Tough
(tough77 @ ieti.org)
In last month's Guest Editorial, Prof. Mario Zadnik introduced the idea that cosmic rays may
fatally damage interstellar probes.
Actually, we probably need not worry much about this.
Here are some reasons for not worrying:
- No one else seems worried. In all the NASA material
and web sites on interstellar travel that I have checked out,
nothing is said about cosmic rays. Nor in the nanotechnology
literature, as far as I can recall. Nor in the National Space
Society position paper. Nor in any of the other 35 references
in my "Small Smart Interstellar Probes" paper (preprint at
- We have to remember that any civilization we are likely
to detect is probably thousands of years ahead of our
technology. Even now, our nanotechnology literature
indicates that within a few decades we will be able to
manufacture "active materials" atom-by-atom. These
intelligent active materials will incorporate sensors, diagnosis,
and repair capacities right in the material itself. So any cosmic
ray damage could presumably be repaired. (Nanotechnology,
like interstellar probes, has become widely accepted within
mainstream science over the past 2 years.)
- We need not worry about a probe surviving for "a few
million years" as Zadnik mentions. A few thousand years might be
enough if the probe travels only a few hundred lightyears.
- If our satellites and space station and interplanetary
probes had been devastated by cosmic rays, I would worry
more. You are right, they have been in existence only a
fraction of the time needed for interstellar travel, but still they
are the best practical test so far of likely damage from cosmic
All in all, as we think about a civilization thousands of
years ahead of our technology, it seems unlikely that cosmic
rays will stop their interstellar exploration.