“If we can perturb an asteroid out of impact trajectory, it follows that we

can also transform one on a benign trajectory into an Earth-impactor.”

 

Carl Sagan and Steven Ostro

Dangers of asteroid deflection

Nature, 1994, Volume 368

 

***

 

 Gravity’s inexorable pull gathered primordial grit left over from the dawn of creation and shaped the gray graveled mass into a sphere. Lifeless, silent, it drifted in the absolute cold of infinite space. Interstellar, it arrived and passed through the outer darkness, across the paths of myriad bodies orbiting their central star, altering the course of one, leaving angst, and opportunity, in its wake.

 

***

 

      The Agency’s supercomputer labored for more than a week, executing trillions of floating-point operations every second. Accurate trajectory computations were insanely complex. In addition to the Sun itself, all the bodies in orbit around it attracted every other body. And there were many.

      In his very secure executive office, he copied the result into a flash memory chip, then carefully inserted it into the cap of his silver Montblanc pen. The dangerous values escaped the building and found their way to his home near the nation’s capital. The select few in his cellar raised a toast with premium French brandy in fine, cut crystal glasses: “To the future … to a new world order.”

      The men unleashed their control files, hacked into the Intergovernmental Mission Control Center communications labyrinth. Time and duration values rode the space-communications backbone and arrived at the asteroid just before it disappeared behind the Sun, beyond the orbit of Mars.

      The deflection system responded. The velocity vector changed according to the dictates of this clandestine group.

      Weeks later, the Sun no longer occulted the line-of-sight to the asteroid. But Earth-bound telescopes could not see it through blue sunlit skies. Close to the limb of the Sun, space telescopes looked away from it, rather than risk damage to sensitive optics.

      Finally, the errant asteroid could be seen in the night sky. Ellipsoidal, the slowly-tumbling lump of gray was much too far away for radar astronomy. Legions of ground telescopes turned toward it. Refined trajectory data were loaded into identical orbit models on two supercomputers; one lived secretly at the Agency, the other far across the country at the Jet Propulsion Laboratory.

     The tensely-awaited prediction again took over two weeks. It was not a wide miss with zero likelihood of catastrophe, as the Center had expected, as they thought they had commanded. The probability of Earth impact increased over twenty-one times! The cross-hairs of the likelihood ellipses changed to a point a few hundred kilometers southwest of a large city, with just 3 years and 66 days before impact.

     The warning spewed out with withering effect: panic ensued, suspicions arose, cooperation thinned. The international asteroid defense effort froze in uncertainty. But the countdown could not be stopped. Days decremented to possible ground impact along the now-deadly trajectory.

 

 Elcano and Wākea

[9 Years 325 Days before Impact]

 

      Telescopes rested on the northwest shoulder of the red-rocked rim of the caldera on the Spanish island of La Palma. The road leading there followed creases and contours sculpted over eons. It curved back and forth like a paved mountain snake.

      Elazar gripped the door handle. Tomás drove at a youthful speed. They’d been here before; Tomás knew the road. The rented SUV swayed with the curse of nausea. “Tomás! Tomás! Please slow down. I may vomit my airplane lunch.”

      “Yes, Professor. I’m sorry.”

      “Tomás, I was young once, always in a hurry to absorb life and learn its secrets. Now I look to the stars.”

      The accommodations for Gran Telescopio Canarias were comfortable, suitable for visiting astronomers. Their scheduled observing runs did not start until the evening of the next day. The flight from Madrid was short, just three hours. But the old man needed to be well-rested, as his age and declining health required.

      The next morning, over a light breakfast, they talked. Hair thin and gray, skin wrinkled with wisdom, Elazar pointed his shaking bony finger to the objectives: the schedule and telescope settings placed before him by Tomás. Professor Etxarte’s favorite graduate student was working on his doctoral thesis topic: Blue Stars of the Pleiades.

 

      Elazar Etxarte had come a long way from the town of Getaria on the coast in the far north of Spain. His father had been a fisherman and wanted Elazar to follow in his footsteps over the gangplanks to the boats. But the lure of the stars over a nighttime sea, and chronic seasickness, pulled him in a different direction, through a university education to an esteemed position at the prestigious Universidad Complutense de Madrid. He became a respected professor of astronomy, attracting graduate students to this noble ancient discipline and to his classes.

      Elazar flew frequently to La Palma. He did so now with greater interest since Gran Telescopio Canarias had achieved First Light. In flight, he often looked down with pride at the sea surrounding the islands. Five centuries earlier, Magellan’s fleet had sailed from Seville to Tenerife, one of the Canary Islands, the first leg of the famous around-the-world voyage. A Basque sailor and navigator, also from Getaria, Juan Sebastián Elcano, had been the master of a ship in Magellan’s fleet on that first leg. Despite being in the air over the same sea, and not on a wind-driven sailing ship, Elazar felt strongly connected to Juan Sebastián.

 

      Elazar felt refreshed after his needed mid-day nap. Tomás respectfully opened the passenger-side door for his professor, held Elazar’s elbow, and helped him up and in, then took the wheel and drove off at an acceptable speed. Like the day before, the road was curvy, but now it wasn’t far to the big telescope. Tomás parked so they could see the western horizon while still comfortably seated inside. Elazar always looked forward to the setting Sun, not only for its beauty as the nearest star, but also for the black clear night that usually followed. They watched as the tops of the white clouds below were swept with a beautiful red-orange hue as the Sun dipped below the ocean’s horizon.

      Inside the observatory, Tomás worked with the telescope operator who called up the ephemeris for the Seven Sisters, the Pleiades: right ascension and declination versus time for the telescope’s location. Their attention turned to the new spectrograph. Elazar looked over his student’s shoulder like an expectant father.

      The computer now controlled the super-accurate pointing of the optical machine. The physical span of its light-collecting reflecting surface, an inverted geodesic dome of 36 rapidly-adjusted, abutting hexagonal mirrors, was the largest on the planet. On another volcanic island, in another ocean, ultra-sophisticated adaptive optics had been ingeniously engineered into the observing system. The image-correcting technology of the pair of giant Keck telescopes on Mauna Kea had also been designed into Gran Telescopio. While the aperture of the grand telescope was larger, the site was lower with more image-distorting atmosphere above. But, as often cited by Spanish astronomers, oxygen deprivation was not a problem for those at this telescope.

      Elazar and Tomás had gone through this same ritual some months earlier at Gran Telescopio, with an older imaging spectrograph. Tomás now confirmed that the new higher-resolution device had been correctly installed and calibrated. In the previous visit’s imagery, Elazar had noted a faint point of light amid the dimmer siblings of the Seven Sisters. But it was white, not tinted blue by the nebulae in the intervening line of sight. Maybe the older spectrograph had produced an image error.

      Astronomical discovery was always exciting. The massive 400-ton telescope moved slowly, smooth as machined silk, into precise position as the image of the Pleiades rose into view in the clear darkening sky. The Seven Sisters and the fainter stars of this mythological constellation remained fixed in their well-known pattern ... except for the small white one. It was still there and still white, but when compared to the earlier images, it had moved! Professor Etxarte exercised his authority and changed the observing objectives.

      Gran Telescopio automatically recorded the observing arc data of the moving white object this night and over the following two weeks. According to international agreement and protocol, Elazar sent the data to the Jet Propulsion Laboratory in California and the International Astronomical Union’s Minor Planet Center in Massachusetts. They computed the trajectory of the point of reflected light with sufficient accuracy and applied a huge database of predicted positions of known asteroids to determine if the tiny white one matched any of them. It did not!

      Enormous computational power swung into action. The object’s predicted trajectory was determined: interstellar. It would slice through the ecliptic, the plane of the Earth’s orbit around the Sun, at a slight angle. Its path was open, hyperbolic, taking it on a one-time pass through the solar system, never to return. Its trajectory brought it closer to the Sun than the Earth’s orbit, qualifying it as a Near-Earth Object. But it would miss the Earth by a wide margin. If it had been on a collision course, there would have been no time to do anything other than to warn, create panic, and to flee from the area around the computed point of impact.

 

      Upon his return from La Palma, Elazar announced his retirement. That wasn’t a surprise, with many years to his credit. But there was more. Test results came back to his doctor while he’d been away with Tomás. Cancer was confirmed. It had spread and was terminal. Elazar elected radiation treatment, but to little avail. His remaining days were numbered as to when his human elliptic orbit would open up to a spiritual hyperbolic trajectory, never to return, to where he would be among the stars forever.

      Feeble and gaunt, Elazar entered the crowded office. “I’m sorry to be late.”

      The president of Universidad Complutense stood and welcomed him. “Professor Etxarte, please do not worry. Your discovery is important, for the university.”

      Elazar took his seat at the conference table. The radiation treatment had taken longer this time. “I, or rather we, have discovered a celestial body, a special one. I will submit the name Elcano to the IAU. Even though it is not in a closed orbit, its trajectory has been determined.”

      There was unexpected pushback. “But Elazar, the Spanish del Cano is more appropriate for our university.”

      Elazar looked around the office, “Tomás. What do you think? You were at my side during the observing runs.”

      “Professor, what can I say? I am from Madrid. I understand your reasons, but I think del Cano should be its name.”

      “That’s what you Spaniards would say!” Tension built in the suddenly quiet room. Separatism in the north still echoed in their minds. Elazar knew that Basques predated the Castilians by thousands of years. All in the room knew that Elazar had the honor of proposing a name for his discovered space traveler.

      In an absolute, authoritative tone, Elazar countered with, “My dear friends, need I remind you that I am from Getaria, the home of the Basque navigator Juan Sebastián Elcano, Juan Sebastián del Cano, as you would speak it. As you must know, he was the one who brought the remaining ship of Magellan’s fleet, the Victoria, the rest of the way around the world after the catastrophe in the Philippines. Like our passing celestial visitor, Elcano was also a traveler in a new world.”

      “Why not name it Victoria?”

      Elazar stood abruptly. “No! Elcano. It is my choice.” With that, the meeting was over.

 

      Back in his office, Elazar sat down at his desk, bending over, wincing from abdominal pain. Recovered, he sat up, sweating, and looked for quite some time at the framed photograph on the wall. It was of the statue of the famous navigator in the town square of Getaria. Many times he had walked around this statue, had touched it, and had read the inscription with proud understanding. Elazar clicked the send icon and slapped his desk. “Elcano it is!”

      The IAU agreed.  Return