"02 - Birth of an Age" - читать интересную книгу автора (BeauSeigneur James)

about the room he gained a different perspective of the people and objects in the other room.

Dr. Xiou introduced Mary to Dr. Waters; everything was there but the handshake.

"Hi, Mary. I'm glad you're here to see this," Dr. Waters said, blurring even further the distinction between 'here' and 'there.'

"Hello, Dr. Waters," Mary responded. "It's nice to finally meet you."

"You, too, Mary; and please, call me Jim." Man' nodded agreement.

"Frankly, Man'," Waters began, "what you've found has got all of us stumped out here." Waters pressed one of the function keys on his computer keyboard and the picture on Xiou's wall display was instantly replaced by a composite image with a close-up of Waters in the upper right corner and the rest of the screen filled with what Man' quickly recognized as one of the images on which she had made her discover}'. "This first shot," Waters began, "is one of those taken last month, on May 20th, with the three objects appearing here, here and here." As he spoke, he used his mouse to point to each of the objects in turn. "The second picture," he continued, as the image changed, "was taken last night. You'll note that the albedo of each of the objects Ч again, here, here, and here Ч has increased noticeably as they've moved closer to earth."

"Excuse me, Jim," Dr. Xiou said. "You keep referring to them as objects; are they asteroids or not?"

"The best answer I can give you at this point," Waters answered, "is, I guess so. Their orbits are much more like what we'd expect from comets than from asteroids, with an aphelion well beyond the orbit of Neptune and a perihelion halfway between the orbits of Mercury and Venus. What has us stumped is where they came from and why we haven't seen them before. Based on their course and speed, we've plotted their orbits and have determined that they are definitely earth-crossing, which would make them Apollo-class asteroids, and yet none of our previous surveys has identified them."

"Any theories at all?" Xiou asked.

"Well, according to our projections, their orbits bring them inside the orbit of Jupiter for a period of only about two and a half years of their fifteen-year orbit. It's possible that we've simply not

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been looking in the right place when they've been near enough to be of interest, but, frankly, I doubt that with the amount of attention that's been focused on the Apollo-class asteroids, that everyone could have missed three asteroids of this size. We're going through the archives researching that right now. Another possibility is that they are wandering planetoids from outside our solar systems which have only recently been captured by the sun's gravitation.

"The two asteroids closest to the earth, 2021 KD and 2021 KE Ч I understand you're calling them Calvin and Hobbes," Mary smiled and nodded, "are only about 350,000 kilometers apart, which is relatively close. The largest one, 2021 KF Ч the one you've named Wormwood Ч is lagging approximately 67 million kilometers behind. As 1 mentioned, all three of them are fairly large as the Apollo asteroids go. The first one, 2021 KD, is irregular, being roughly kidney-shaped, and has an average diameter of about twenty kilometers. The second one, 2021 KE, is spherical and has a diameter of about three kilometers. 2021 KF, though, is a monster with a diameter of nearly fifty kilometers, which would make it the largest of the earth-crossing asteroids, dwarfing even Eros, which is oblong with a width of about twenty kilometers," he said, referring to the largest of the previously-discovered asteroids whose orbits intersect the orbit of the earth.

"How close will their orbits bring them to the earth?" Dr. Xiou asked.

"Well, that's why I'm calling." Dr. Waters reached for his keyboard and pressed another function key. As quickly as he had completed the task, the image on the screen rotated to give a computer-generated overhead view of the portion of the solar system between the sun and a point beyond the orbit of Mars where the asteroids were located at the time of the most recent photographs. At the upper center of the screen were the three asteroids, which appeared as no more than specks of light against the vastness of even this tiny fraction of the solar system. "We ran the data we have on the asteroids' paths through the computer and came up with a simulation. This is what we got." Waters started the simulation and each of the bodies began to move, tracing out their orbits across the screen. Quickly the asteroids moved through a steep arch, dropping counterclockwise toward the lower left. In the upper left hand comer of the screen a counter showed the dates

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as the simulation progressed. Lower down on the screen, the earth traveled along its nearly circular path around the sun.

As the simulation progressed, a sick feeling came over Dr. Jung Xiou. Mary Ludford's mouth dropped open and then quickly shut as she bit her lip. As the counter clicked off each additional day, the orbits of the two leading asteroids brought them closer and closer to the earth, and a conclusion began to appear frighteningly inescapable. Just as a collision seemed imminent, the picture on the screen zoomed in for a much closer view, from which it was evident that the first two asteroids would actually just miss the earth.

"As you can see, we're talking about two very close passes," Dr. Waters said as the two asteroids on the simulation passed by the earth, barely avoiding a collision. Waters stopped the simulation for a moment in order to elaborate on what they had just seen. The simulation's calendar stopped on July third. "We're running these estimates through again," he said, "and watching the asteroids very closely, but it appears that 2021 KD could come as close as 800 kilometers. 2021 KE may come even closer, within about 500 kilometers. It could even come in brief contact with the outermost atmosphere. If so, then based on the trajectory, it will simply skip off the atmosphere the way a stone skips across water when it's thrown at a shallow angle. Both 2021 KD and 2021 KE should provide an exciting opportunity for some once-in-a-lifetime viewing. At the expected distances, 2021 KD will appear in the sky more than twice as large as the moon, and if 2021 KE does indeed skip off the atmosphere, there will be some fantastic fireworks."

"That's great, Jim," Xiou said. "But 1 have to admit, you had me worried."

"Well, that was the good news."

"What do you mean?" Xiou asked.

"Well, the problem is with 2021 KF. The orbits of all three asteroids have a similar inclination, ranging from 41 degrees to the ecliptic for 2021 KD and 2021 KE to just less than 38 degrees for 2021 KF. But, whereas 2021 KD and 2021 KE are in nearly identical orbits around the sun, 2021 KF's orbit is much larger. Right now the three are fairly close in cosmic terms, but that's merely a coincidence. Their paths will continue to grow farther apart as they come closer to the sun. What that means, as you'll see

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when we run the rest of the simulation, is that 2021 KD will intersect the earth's orbit at point A on July third followed by 2021 KE less than three hours later/' As he spoke, a white capital 'A' appeared on the screen at the appropriate location where the orbits of the first two asteroids had passed the earth. '"2021 KF's orbit, however, will intersect approximately forty-three days later at point B." A capital 'B' now appeared below and to the left of the capital 'A.' "Were their orbits more alike, so that 2021 KF would also intersect somewhere near point A, then by the time it got there, the earth would be 64 million miles farther through its orbit, and well out of danger. Instead, if my preliminary calculations are correct, it will intersect the earth's orbit at point B on August fifteenth."