“Screw the mission plan.” He switched off the automatic pilot. “We’re not robots, following a programmed script. What’s the point of sending actual flesh-and-blood humans into space if we can’t react to unexpected circumstances and take advantage of amazing new opportunities?”
“Woo-hoo!” Zoe cheered him on. “You tell ’em, Skipper.”
“Hush!” Fontana said. “The grown-ups are talking.” She gave him a worried look. “I don’t know, Shaun. Maybe we should run this by Mission Control first.”
“There’s no time for that,” Shaun said. Radio waves traveled at the speed of light through the vacuum of space, but there was still more than an hour’s time lag when it came to communicating with Earth, and that wasn’t even figuring in the bureaucracy factor. “That comet — or whatever it is — is going somewhere. I don’t want it to get away while they’re holding conferences back home.” He looked her in the eyes, struck as always by their brilliant green depths. “I don’t know about you, Alice, but I want to know what that so-called comet is.”
“You think I don’t?” She searched his face. “You really think this might be a UFO, Shaun?”
“To be honest, I don’t know what to think.” He toyed with the dog tags around his neck. “Like the doc said, we’re in unknown territory here.”
“Well, that’s the job description, isn’t it?” Fontana sighed and settled back into her seat. He recognized the determined set of her jaw. “All right. Let’s go find out what’s driving that puppy.”
Shaun turned toward O’Herlihy. This decision could have an enormous, and possibly catastrophic, effect on their careers. They could even be risking their lives. He needed to make sure his whole crew was okay with it. “Marcus?”
“You’re in charge of this mission, Colonel. It’s your call.” The scientist’s gaze remained glued to his monitors. “But personally, I would never forgive myself if we didn’t at least try to solve this mystery.”
Shaun felt the same way. “Okay, it’s decided, then.” He had never been more proud of his crew. “Keep the LIDAR locked on that comet. Track its every move.”
“I wouldn’t dream of doing anything else.”
Zoe waved her hand in the air. “Hey, don’t I get a vote?”
“No,” Fontana said in no uncertain terms.
“Fair enough,” Zoe said with a shrug. “Although, just for the record, I think you folks are acting like real starship heroes.”
Fontana rolled her eyes. “Why don’t I find that reassuring?”
It took several minutes to calculate an intercept course based on the comet’s current trajectory. They would have to leave Sacagawea behind. The probe’s thrusters had been intended for only minor course corrections; they lacked the power for this sort of chase. Shaun would have to be careful not to expend too much of the Lewis & Clark’s own engine power on this unplanned expedition. Mission Control would have a cow when they found out about it.
It will be worth it, Shaun thought, if we can make contact with a genuine UFO.
“Everybody strap yourself in,” he advised the crew and the stowaway. Zoe took a seat at the computer station next to O’Herlihy. She tapped out a few last notes on her tablet before stowing it away for safekeeping. “We’re hitting the gas.”
“Tally-ho,” Fontana said drily.
Shaun fired up the thrusters and initiated a controlled burn to accelerate the ship in the direction of the probe. The nose of the command module tilted as he altered the angle of their orbit to bring them into the same plane as their quarry. The Lewis & Clark climbed toward Saturn’s north pole. The planet’s axial tilt worked in their favor, as did the fact that Saturn was somewhat squashed in shape, being wider around the middle than from top to bottom, but because of the sheer size of the gas giant, it still took two-plus hours before they finally found themselves gazing down at the top of the planet.
“Whoa!” Zoe exclaimed. “What happened to the hexagon?”
Shaun was wondering the same thing. The celebrated six-sided vortex, which had been unchanged for decades, was visibly diminished. Its borders had contracted, so that it appeared to have shrunk in size by at least a third, and its color had faded, too, making it somewhat harder to make out against the planet’s turbulent yellow atmosphere. It almost looked as though the vortex was gradually shrinking away.
But was that even possible?
“Marcus?”
“I see it,” O’Herlihy replied tersely. “And no, our eyes are not deceiving us. The vortex has noticeably decreased in both size and intensity, almost thirty-two percent since the last time we analyzed it.”
“Why didn’t we notice this before?” Shaun asked.
O’Herlihy shrugged. “We weren’t looking for it, and there’s been a lot of Saturn, including its various rings and moons. Plus, it appears that the rate of the shrinkage has increased exponentially with the approach of the comet.”
Shaun didn’t like this. The hexagon, the rings, the comet — nothing was acting as it was supposed to. He supposed it could be seen as a lucky break that the Lewis & Clark had arrived in time to witness these astounding developments, but it didn’t feel that way. He was starting to wish they had gone to Mars instead.
“What about the comet?” Fontana asked. “Where is it now?”
O’Herlihy consulted the LIDAR. “Oh, my God. You’re not going to believe this.”
At this point, Shaun was ready to accept just about anything short of a flock of winged unicorns. “Try me.”
“It’s come to a dead stop nine hundred kilometers above the planet’s north pole.” Zoe started to open her mouth, but O’Herlihy beat her to the punch. “Yes, directly above the hexagon.”
“I don’t understand,” Fontana said. “How does a comet come to a stop?”
“You tell me,” the scientist said, sounding somewhat overwhelmed by the unexplainable phenomena he had been confronted with recently. “But the comet is definitely parked in a stationary position above the pole. Not an easy feat to pull off, by the way, even for a satellite.”
Shaun knew what he meant. Geosynchronous orbits were easier to maintain above a planet’s equator, where the satellite’s orbit could be matched to the planet’s rotation. A satellite would have to be able to modify its orbit continuously to “hover” in place above the pole. Back on Earth, solar sails had been employed to attempt this, with mixed results. Shaun had no idea how a comet could do it — unless it wasn’t really a comet.
“I’m bringing us in closer,” he said. “I want to see that thing with my own eyes.”
Operating the thrusters manually, he cruised a kilometer above the comet. Because the ship was in an inverted position, with its belly facing away from the planet, they were able to gaze up at the “comet” as it hovered hundreds of kilometers above the anemic hexagon.
C/2018 floated like a hot-air balloon beneath them. To Shaun’s surprise, it was glowing much more brightly than before. Its misty coma expanded as jets of vapor steamed off the comet’s frozen nucleus, which appeared to be dissolving before their eyes.
“Huh?” Zoe said. “Is it supposed to be doing that?”
“No,” O’Herlihy said, sounding torn between dismay and wonder. “Not this far out from the sun. Granted, Saturn also radiates its own heat but not enough to melt a comet like that!”
Shaun stared at the comet, which was shrinking like an ice cube on a hot summer day. Its icy core seemed to be subliming directly from solid to gas, skipping the liquid state. Billowing clouds of vapor poured off the nucleus. Solar winds blew the gas back into the comet’s tail, which was wrapping around the planet below before dissipating into the vacuum. He had never seen anything like it.