AS NEAR AS WE CAN TELL, THERE IS NO INHIBITION AGAINST KILLING ANOTHER SPECIES SIMPLY BECAUSE IT DISPLAYS HIGH INTELLIGENCE. SO, AS MUCH AS WE LOVE HIM, CARL SAGAN’S THEORY THAT IF A SPECIES MAKES IT TO THE TOP AND DOES NOT BLOW ITSELF APART, THEN IT WILL BE NICE TO OTHER INTELLIGENT SPECIES IS PROBABLY WRONG. ONCE YOU ADMIT INTERSTELLAR SPECIES WILL NOT NECESSARILY BE NICE TO ONE ANOTHER SIMPLY BY VIRTUE OF HAVING SURVIVED, THEN YOU OPEN UP THIS WHOLE NIGHTMARE OF RELATIVISTIC CIVILIZATIONS EXTERMINATING ONE ANOTHER. IT’S AN ENTIRELY NEW SITUATION, EMERGING FROM THE PHYSICAL POSSIBILITIES THAT WILL FACE ANY SPECIES THAT CAN OVERCOME THE NATURAL INTERSTELLAR QUARANTINE OF ITS SOLAR SYSTEM. THE CHOICES SEEM UNFORGIVING, AND THE MIND STRUGGLES TO IMAGINE CIRCUMSTANCES UNDER WHICH AN INTERSTELLAR SPECIES MIGHT MAKE CONTACT WITHOUT TRIGGERING THE REALIZATION THAT IT CAN’T AFFORD TO BE PROVEN WRONG IN ITS FEARS. GOT THAT? WE CAN’T AFFORD TO WAIT TO BE PROVEN WRONG. THEY WON’T COME TO GET OUR RESOURCES OR OUR KNOWLEDGE OR OUR WOMEN OR EVEN BECAUSE THEY’RE JUST MEAN AND WANT POWER OVER US. THEY’LL COME TO DESTROY US TO INSURE THEIR SURVIVAL, EVEN IF WE’RE NO APPARENT THREAT, BECAUSE SPECIES DEATH IS JUST TOO MUCH TO RISK, HOWEVER REMOTE THE RISK.

KIND OF MAKES YOU WISH WE’D STAYED IN FRONT OF CAVES MILKING GOATS, DOESN’T IT?

FROM JILL TARTER, NASA/SETI
TO JIM POWELL AND RICHARD TUNA
JULY 16, 1987

I THINK THE SCIENCE FICTION WRITER JERRY POUR-NELLE PUT IT BEST WHEN HE SAID YOU GUYS MUST HAVE FASCINATING NIGHTMARES. (RELATIVISTIC BOMBS INDEED! YOU ARE TRULY THE PABLO PICASSO AND SALVADOR DALI OF NUCLEAR DESTRUCTION!) ALL OF THIS IS VERY NEW TO ME. NOT UNTIL RELATIVISTIC FLIGHT BEGAN TO LOOK ACHIEVABLE WAS THERE CAUSE TO BELIEVE THAT BROADCASTING OUR PRESENCE TO THE REST OF THE GALAXY MIGHT BE DANGEROUS.

I HAVE SPOKEN AGAIN WITH ISAAC ASIMOV, AND HE SAYS COLONIES INSIDE THE ASTEROIDS MAY BECOME THE ONLY UNPREDICTABLE ELEMENT IN YOUR EQUATION. HE BELIEVES THAT ASTEROID-BASED COLONIES, IF AND WHEN THEY DEVELOP, WILL INEVITABLY START LEAVING THE SOLAR SYSTEM, SOMEWHAT LIKE DANDELION SEEDS. AND UNLIKE YOUR VALKYRIE ROCKETS, SLOW-MOVING COLONIES WILL NOT EMIT A DISTINCTIVE GAMMA RAY SHINE OR BLUSH RADIO PULSES WHEN THEY IMPACT AGAINST INTERSTELLAR HYDROGEN AND DUST GRAINS. IT WILL THEREFORE BE VERY DIFFICULT FOR ANY WOULD-BE EXTERMINATORS TO FIND AN ASTEROIDLIKE OBJECT DRIFTING BETWEEN THE STARS. ESPECIALLY IF IT IS ONLY FIVE OR SIX KILOMETERS IN DIAMETER AND HAPPENS TO BE PAINTED BLACK. YOU SIMPLY CANNOT SEE THEM, EVEN IF YOU HAVE REASON TO SUSPECT THEY EXIST. ANYONE TRYING TO STERILIZE THE SOLAR SYSTEM WOULD HAVE NO IDEA HOW MANY OF ISAAC’S DANDELION SEEDS WERE OUT THERE OR WHERE THEY WERE HEADED.

FASCINATING NIGHTMARES, YES. ALMOST MAKES ME HOPE THAT WHAT THE GREAT SILENCE REALLY MEANS IS THAT WE ARE ALONE IN THE GALAXY. ALL ALONE.

I SHOULD PROBABLY ALSO ADD THAT KAMEN AEROSPACE VICE PRESIDENT JOHN RATHER POINTS OUT: “IF WE EVER DO GET A SIGNAL ON OUR RADIO TELESCOPES, ONE HAS TO WONDER WHAT MIGHT BE IMPORTANT ENOUGH TO TELL US. THE INITIAL TRANSMISSION COULD BE SOMETHING AS ELEMENTARY AS AN ALERT SIGNAL, REQUIRING THE CONSTRUCTION OF VERY SOPHISTICATED COMPUTERS TO DIG OUT VAST AMOUNTS OF INFORMATION CONTAINED IN THE ALERT. WHAT THEY MIGHT IN REALITY BE TRANSMITTING ARE INSTRUCTIONS FOR THE REPLICATION OF AN ALIEN PROGRAM ON EARTH, SEDUCING US, AS IT WERE, INTO CREATING A SORT OF ELECTRONIC CLONE. AND THERE’S NO TELLING WHAT THAT SAVAGE BRAIN MIGHT DO, ESPECIALLY IF WE ARE CARELESS ENOUGH TO LEAVE ITS MODEM WORKING. IT COULD ACCESS COMPUTERS ALL AROUND THE WORLD—REPROGRAM THE ENTIRE PLANET IN LESS THAN AN HOUR.”