390,000 kilometers. On the ten-point Torino Impact Hazard Scale, the asteroid rated only an anemic score of one, hardly noticeable.
To be ultraconservative and thorough, Gershon had assigned his best student, Govind Naidu, to relook at the asteroid and update its orbital parameters. The NASA project had a priority designation, and Naidu was able to cut into the queue to task the forty-eight-inch telescopes at the Maui Space Surveillance Site and at the Palomar Observatory to reimage 137108. He was also given eight precious hours of time on the government’s supercomputer at the National Energy Research Scientific Computing Center at the Lawrence Berkeley National Laboratory.
“You’ve got the new MSSS and Palomar data?” Gershon asked.
“Yeah. You want to go over to my workstation?”
“Just log on from here.”
“You’ve got mayo on your keypad.”
“And this is against your religion?” Gershon got up and relinquished his chair. “I’ve got a telecon with JPL this afternoon, and I want this nailed.”
Naidu sat down and logged on to the observatory databases. “Okay, here’s the orbital plot for 137108 as of the last observation point in July 2008. Right now, it’s past Jupiter heading inbound with an orbital period of 1.76 years. Here’s the last simulation-let me fast-forward to August 2027. You see, there, it gets within 400,000 kilometers of us.”
“I need the new data, Govi.”
“I’m getting there.” He clicked through and opened spreadsheets that were time-stamped to the previous night. “Okay, both telescopes got clean images. Let me merge the databases from Hawaii and Palomar. It’ll just take a minute.”
His fingers flew over the keyboard as he conformed the two sets of observations, and when he was done, Gershon said, “Let’s see it.”
Naidu clicked on the orbital plotting tool and fast-forwarded the simulation to 2027. “See? It’s unchanged. The closest point is still in August at a distance of almost half a million kilometers. On February 9, it’s not even close.”
Gershon looked satisfied. “So that’s it. We can scratch 137108 off the oy vey list.”
Naidu didn’t get up. He was accessing the Lawrence Berkeley database. “I thought you might get more questions, so I ran a series of scenarios on the NERSCC supercomputer.”
“What kind of scenarios?”
“Asteroid-asteroid hits.”
Gershon grunted his approval. The young man was right, he’d probably get the question. There were about five thousand asteroids in the main belt between Mars and Jupiter, and it wasn’t unprecedented for them to slam into each other from time to time, changing their orbital characteristics. “How’d you model it?”
Naidu puffed out his chest and proudly described a sophisticated statistical model he’d constructed which exploited the massive computing power at the NERSCC to examine hundreds of thousands of hypothetical asteroid- to-asteroid strikes involving 137108.
“Lot of second-body variables,” Gershon whistled. “Mass, speed, angle of contact, orbital dynamics at point of collision.”
Naidu nodded. “Each potential hit can change every parameter of 137108. Sometimes not by a lot, but you can get meaningful differences to the aphelion, the perihelion, the orbital period, the ascending node longitude, the inclination, the argument of perihelion, you name it.”
“So show me. What do you have?”
“Okay, since I had only eight hours of computing time, I limited the model to about five hundred higher- probability asteroids based on their orbital characteristics with respect to 137108. Only one simulation out of six hundred thousand produced something interesting.”
Naidu launched a graphical-simulation program and provided running commentary. “This one assumes an asteroid-to-asteroid collision between 137108 and 4581 Asclepius, an Apollo-class object that’s just a little guy, about three hundred meters diameter. It passed within 700,000 kilometers of earth in 1989. If it had hit, it would have been no big deal,” he snorted, “just the equivalent to one Hiroshima-sized explosion every second for fifty days! This simulation assumes 4581 gets tweaked by another rock, gets its own orbit perturbed, and hits 137108 near Jupiter in March 2016. Here’s what goes down if that happens.”
Naidu set the orbital simulator to run from the present. On the screen they watched a green dot representing 137108 move through the solar system in an eccentric elliptical orbit, approaching the earth approximately every two years, then sling-shotting past Jupiter before turning back again toward the sun.
When the simulation got within five years of 2027, he slowed it down so they could watch it more carefully. They stared at two independent orbits, the earth’s and the asteroid’s, a green dot and a red dot moving through the solar system. At a January 2026 time-point, Naidu slowed the simulation again to a snail’s pace.
Gershon leaned in over his student’s shoulder. “It’s really hard to say visually whether its new orbital is going to make things better or worse.”
Naidu said nothing.
The clock turned slowly and at mid-2026, asteroid 137108 turned toward the sun. The earth’s orbit was slowly positioning the planet to get close to an intersection with the asteroid’s track.
October 2026.
November 2026.
December 2026.
January 2027.
The red and green dots were getting close.
Then February 2027.
The simulation halted on February 9.
A pop-up box appeared on the screen:
Impact Probability-100 %****Torino 10**** Torino 10****Torino 10****
Gershon gasped. “The asteroid’s size. Does it change postimpact with 4581?”
Naidu scrolled down to a table, double-clicked on a cell, and pointed. “It’s still huge, a game-ender.” He logged off the terminal and stood up. “It’s all hypothetical, but I thought you needed to see it. We’re not talking about large probabilities.”
Gershon looked out the window. It was a blustery fall day, and sharp gusts were separating the last leaves from their branches. He had an urge to feel the wind on his face and to crunch through the dry leaf piles on the lawn.
He gently touched his student’s shoulder, and said, “I’m sure you’re right, Govi. Listen, I’m going to go out for a little walk.”
Two weeks later
Aracas,Venezuela
The earthquake struck AT 11:05 A.M. The epicenter of the 7.8 mag event was twenty kilometers east of Caracas along the El Pilar Fault. At the moment the first tremor hit, the day was sunny and windy, the sky, hazy blue with wisps of fast-moving clouds. Forty seconds later, the sun was blotted out by plumes of concrete dust rising above pancaked apartment blocks, high-rise offices, municipal buildings, and schools. Then ruptured gas lines started fires, which were wind-whipped into conflagrations that roared through the historic Altamira district and the Parque Central Complex.
Eighty percent of the 220,000 casualties occurred within seconds of the first shock-men, women, and children mercilessly crushed to death by steel, glass, and masonry. Most of those trapped under the rubble would fall victim to slow dehydration. Others would be killed by the serious aftershocks and fires which plagued the city for the next seventy-two hours.
Incoming telemetry lit up the Global Seismographic Network like a Christmas tree. At the USGS monitoring
