Previous: Chapter Fourteen: The Hero Twins
The morning sun was starting to heat the fog bank, lifting it skyward. The furthest wall of the cenote disappeared from view, and then there was just a cylindrical pillar of fog before them, rising out of the vast pit.
Merl fixed a new battery into the drone. MaryLiz touched the controls and launched the drone skyward. It spun once to recalibrate its accelerometers, then darted straight into the wall of fog and instantly disappeared from sight.
“It’s headed towards the waypoint,” Jo reported, monitoring the drone’s progress. “Lidar is on, and locked in infrared. The drone knows where it is.
Frances’ camera was still set to visible light, but the display from the drone’s hazard camera showed the ghostly terrain of the central island. MaryLiz commanded the next waypoint, and the drone dropped within ten meters of the tree canopy. The drone performed a tight horizontal loop, rescanning the surfaces below at higher resolution.
Jo called out from the monitor. “We were right. Big old gap in the canopy, a good eight meters by ten. Go a meter east and bring it straight down.”
MaryLiz entered the commands and the drone dropped between the branches.
“Ok, let’s drop the camera when you’re about half a meter off the deck. You’re at 3 meters. 2.5. 1.8. 1 meter. 60 cm: drop!
MaryLiz issued the auxiliary command assigned to the drone’s drop solenoid, and the camera fell away from the bottom of the drone. There was a gasp from Frances, who was seeing it all in 3D from the camera’s perspective.
Jo checked the monitor. “The eaglet’s landed. The camera’s upright, and in one piece. There’s the drogue chute, off to the left.”
MaryLiz tapped “Home” and the drone launched skyward, retracing its own incoming path through the tree canopy. They could hear the sound of its motors through the remote camera microphone left behind on the ground, doppler shifting and fading as the drone cruised back to them, landed, and shut down.
Within an hour, the afternoon sun had done much to boil off the fog, and the image on Frances’ camera monitor grew brighter and deeper. Large moss covered slabs of limestone lay scattered across the plain, itself a huge fallen slab of the same material. Green was the dominant color. Water dripped from the edges of the velvet covered rocks, atmospheric mist condensing on the still cool surfaces. From time to time, a flurry of movement tripped the camera’s motion sensing alarm, and the camera kicked into high speed, capturing insects, and once, the shadow of a bat or bird.
In the late afternoon, as the sun lay down on the western horizon, long dark shadows appeared against the far wall of the chasm, against a pale red illumination, the shadows of the trees behind them, projected across the space of the cenote.
The camera motion sensor chirped. Something was moving on the ground at the center of the cenote.
“Wallaby,” said Frances in a whisper, as if the animals could here them over the one-way view. “Two of them. Same species, or I’ll eat ‘em both.”
It was a mother and her joey. The six human observers watched as the baby took a few experimental steps away from its mother, then climbed back into its mother’s pouch.
“Generation 3”, said Jo.
A third wallaby hopped into view, slightly larger than the mother. The newcomer hopped to the mother and baby and nuzzled them affectionately.
Something wasn’t quite right. The buck raised itself high on its back legs, sniffing the air, and turned its head back and forth, ears pricked.
Frances said, “It’s gonna see the….”
The buck launched itself towards the camera, which tilted towards the glare of the overcast afternoon sky. The image changed to paper white. The camera closed its iris to compensate, and the screen went dark as the camera worked to recalculate its exposure settings.
The image recovered. This time the camera wasn’t being dragged along the ground, but carried, either by its lanyard or by the gauze of the drogue chute tied to it, was difficult to say. The camera spun quickly, showing two empty handed paws, before swinging forward again. The image lurched downwards, then upwards again.
“It’s hopping,” said Jo. “It’s definitely got a good grip on the lanyard. It’s going flat out towards the northern rim.”
“We made it even easier for them,” wailed Frances. “We made it easier and they did it again.”
“Drone’s good to go,” said Merl.
“Jo?” said MaryLiz.
“You can give chase, if you want to. The drone will become audible within a hundred meters, best case. Wallaby ears are good. Any closer than that, and you risk disrupting normal behavior.”
“Gotcha,” said MaryLiz. “There’s a mode for that”
The astronaut entered the exclusion zone parameters into the drone and hit “Stalk”. The drone rose and shot horizontally across the sinkhole, headed northeastward towards the rim of the cenote to the crew’s left.
Jo counted down the range until the drone was 50 meters horizontally from the camera, and a hundred meters above it. MaryLiz pointed the lidar scan in the direction of the camera.
“The camera hasn’t moved in two minutes,” said Frances.
“No sign of any wallabies either,” said Jo. “We might have found one of their hoards, like the ones back at the Gift.”
“I’m going to get closer,” said MaryLiz, tightening the tracking parameters of the drone. “They surely know we’re here by now.”
The drone flew in towards the ground, at the base of the towering overhang of the north rim of the cenote. Jo laid the camera view over the lidar map, and the map of the area around the camera began taking on photorealistic textures.
By a jumble of boulders by the water’s edge, a small mound covered with artificial objects came into view: the ribs of a tattered umbrella. A portable radio. Empty beverage containers. A small bucket. MaryLiz realized, from its symmetrical shape, that the entire mound was a midden. 150 years of wallaby hoarding history in one place on earth. Perched at the top was Frances’ camera, easily identifiable by the strip of gauze still attached to its lanyard.
“Cap, may I?” asked Merl. MaryLiz handed the drone controller to Merl.
Merl aimed the drone’s hazard camera straight down. The drone rose a meter, drifted slowly forward by about the same amount, until the ribbon of gauze was directly beneath the cross hairs of the haz cam.
Merl brought the drone forward another three centimeters, opened the jaws of the drop solenoid, and hit “Land”. The drone feathered its lift and dropped straight downwards. When the contact indicator lit, Merl tagged the solenoid control again and lifted off.
When the image from the haz cam stabilized, there was Frances’ camera, dangling like captured prey from the single claw of the drone, as both cleared the canopy and headed straight for the team’s encampment.
Merl offered the drone control back to MaryLiz. “Cap?” MaryLiz shook her head.
“I’m a believer, Merl,” said MaryLiz. “Bring the Hero Twins on home.”
My midnight, the happy band were riding the tram back down the edge of the plateau and back to the Perrera-Perez’s home. Frances sat in the back. As soon as the tram had regained communications range, Frances uploaded the day’s videos to Rad, who had assured the team of the public’s love affair with the mysteriously displaced creatures. Frances took care to heap praise on Merl, whose surprising show of aerial dexterity had saved the earthbound camera.
The coast came into view, stars shone above, competing with the lights of offshore oil drilling platforms miles out in the Gulf of Mexico.
MaryLiz broke the silence. “Gaby, you never finished your story. What happened to Hunahpu and Xblanque?”
“It is a long story. The Hero Twins descended into the underworld of Xibalba, and tangled with the Lords of Xibalba, the rulers of the underworld who had caused them so much torment. They reclaimed their ancestors’ remains, and collected their father’s forgotten artifacts, the equipment with which he played the Mesoamerican Ball Game, the ritualized Luna League Football of its day. Recovering such lost and venerated things would have been a compelling theme for the audiences who first shared the story, long ago.”
“It still is.” said MaryLiz, staring at the ghostly trees, illuminated by the headlights of the tram and streaming along either side of the tram as it descended home through the dark. “But is that ‘The End’? Violent ball playing happily ever after, with dad’s recovered gear?”
“No,” said Gaby. “The twins climbed out of the underworld of Xibalba, their vanquished enemy’s land, soaked with the blood of their vengeance.” Gaby quieted as the tram passed a speed reduction signal. The Perrera-Perez’s garage siding lay around the next bend.
“When Hunahpu and Xbalanque reached the surface, the Twins kept climbing. Up, up, far above the trees, into the sky. The Hero Twins became the Moon, and the Sun.”
Gaby applied the handbrake. MaryLiz jumped out to handle the back gate, and the little tram was home and plugged in to its charger. Frances finished a round of furious texting and followed the rest of the band to the house.
Rad was jazzed. Frances had attached not just the camera videos, but a link to the drone’s lidar surface model of the cenote. The two data sets, combined, could produce a 3D model of the cenote, textured with the images collected by the cameras.
Rad searched for 3D modeling software, and downloaded a free open source modeling program called 3DSee. Rad created a new 3DSee project, and instructed the computer program to load the 3D data from the lidar scan. The drone’s path, determined by GPS, appeared first, as a red corkscrew descending into blackness, then the program began to paint the walls of the cenote in the same sequence as the drone’s original scan.
But slowly. So slowly. Why so slowly? Rad checked the size of the lidar data file. Ten terabytes. At this rate… oh.
Rad’s computer groveled through the huge data set for four hours before Rad threw in the towel. This job would require serious computing horsepower just to reduce the mass of lidar data into a coherent surface model. Checking the size of the video data turned uncertainty to despair. Rad’s experience in 3D modeling was limited to orbital simulations involving General Relativity, in which orbiting bodies were represented as point particles, or spheroids of regular size and density, with no surface detail. And there weren’t that many in a given simulation. The considerable computing power used in such simulations was due to the high resolution of the dynamical simulation, not the comparatively small number of bodies in a given orbital setup. This model was something else entirely, a huge data set with no dynamism.
Rad texted Frances. “I lied. This is too much for me. I’m going to call the Gamers.”