Things last quite a while - perhaps until they are discovered.

            Leonardo Watson looked around the bistro, comfortable with its familiar details. The place was quiet, no surprise as it wasn't due to open for several hours. Narrow red-curtained windows cast a wan light into a room full of wooden tables, cozy and round with white linen. Taking advantage of the early hour, the owner's cat Schrödinger relaxed atop an empty table, sated with kitchen scraps from the previous evening.

            Leo pouted. "I wanted to make this meeting into a field trip. Go see the mission control room." He liked impressive technological arrays, and his own climatology lab had few equals on Earth.

            Three members of the Ancient Secrets Klub occupied their favorite table, in a corner near the kitchen door. On this special occasion, one young guest graced them with her presence.

            Rabbi Naomi Rosenblum was in charge for this meeting; as much, under ASK's arcane traditions, as anyone might claim such a definitive role.

            "You understand our ways," Rabbi Rosenblum told Leo, with good humor that belied her stern wording. She pointed to the floor, where an Ethernet cable snaked across the carpet from their breakfast table to the manager's office. "With data encryption, and our guest's peculiar situation, our usual meeting spot is sufficient."

            Jessica Palomino, the guest in question, smiled with gratitude. "I've hardly budged from my console at mission control in weeks, and I'm glad to get away. I know that setting up this meeting so quickly was a hassle, and the rover team really appreciates your club's willingness to examine the unexpected."

            With this striking young Zuni Indian woman beside him, Leo just couldn't gripe any more. "Ms. Palomino, I've been following your project in the news. Not only has your team won the Lunar Farside Challenge, you guys put three minisats in orbit around the moon, and landed a base station with a sophisticated rover." He felt hungrier for information than for the bistro's excellent menu. "I gather there is more to the story?"

            Rosenblum spoke up. "Leo, perhaps our guest has distracted you? Let us begin."

            "Oops, sorry. Of course." Leo retrieved the club's ceremonial trowel from his briefcase, and held it overhead. "No secret will remain buried forever."

            "That's better." Dr. Nancy Kung winked at Palomino, then brought out the club's antique magnifying glass. "Leo here is quite the brash young fellow."

            Though weary from a long shift at a hospital nearby, Kung grinned. "After the intensity of our recent meetings, I congratulate each of you for attending today." She raised their glass implement and intoned, "The truth shall out."

            Rosenblum said, "Welcome to the 161st meeting of the Ancient Secrets Klub. Ms. Palomino, we're glad you could join us today."

            "I'm glad Dr. Kung invited me." With a hopeful look, Palomino nodded toward the obstetrician. "You folks prefer to work in the background, and you're just the eclectic sort who might solve such an unprecedented puzzle."

            Leo glowed at this implicit flattery. Kung, he figured, must have described some of the club's earlier exploits to their lovely guest. Few people might imagine how much could happen at an ordinary restaurant table.

            Ben Buridan, the bistro's most efficient waiter, brought their meals. "The cook groused a little about coming in at this hour," the young man reported, "but as you can see, his omelets are excellent." A physics major at Tech, a burgeoning university downtown, Ben sometimes helped ASK tackle difficult conundrums. "He went out, so we've got the place to ourselves for a couple of hours."

            "Good," said Palomino, with a trace of apprehension.

            The club members ate quickly, as did their guest.  Soon enough, the cat was daintily examining their leftovers.

            With no other customers to serve, Ben gathered the dishes, then took off his apron and pulled up a high-backed wooden chair. "Today's dessert will be intellectual. I'll serve the sugary kind later, if anyone wants."

            "Can I show you now?" Palomino opened her laptop computer. The others followed suit, linking their screens to hers. "I have our rover data from the past two days, since its successful deployment on the surface. We landed in a region thought to have a variety of exposed strata." A worried expression crossed her angular Native American features. "If word of our discovery gets out, people might think my team is a bunch of kooks."

            Rosenblum said, "You can be confident in our discretion."

            Solomon or Maimonides couldn't have brought more solemn assurance to their words, and Palomino relaxed. She glanced at the older woman, rueful over her expression of mistrust. "Our team checked up on you guys, not that there's much on the record to check. I wanted to be sure, myself."

            "No problem," said Leo. He wasn't quite smitten, but the young MIT student possessed every feature, visible and internal, he found attractive in a woman.

            Their laptops displayed a stark landscape of rock and shadow, reminding Leo of the Apollo lunar landings, which had taken place years before he was born. Prominent was a vertical rock face, with a cave near the middle. The cave had an odd half-circle of an entrance, bringing to mind a cartoon mouse hole.

            "The Lunar Reconnaissance Orbiter didn't image this region very well," the budding selenologist explained. "You can see there is a slight overhang in the cliff face. We spotted the cave almost immediately, and decided to make it our primary target for exploration."

            "You needed to send back a certain quantity of data, correct?" asked Kung. "For the Farside Challenge's prize qualification?"

            "Yes, and we did. That took less than an hour." Palomino brought up some detailed images of lunar rocks, and of gritty soil, technically known as 'regolith.'

            "We analyzed the immediate landing area, dug a few centimeters down, and did a layer-by-layer comparison." Palomino's excitement grew as she leaned forward, almost on her feet. "We found some really odd particles, and that's when we started thinking this wasn't like the regions explored previously. See? Those soft bits, that look crumbled."

            "Have other lunar scientists commented?" asked Dr. Kung.

            "Not yet!" said Palomino. "Not from outside our primary mission team, anyway. Quite the contrary, it's a good thing our minisats and ground stations use strong encryption."

            "Are all the Farside Challenge teams so, uh, cautious?" asked Leo. He didn't mind challenging a genius like Palomino. "In my field, discoveries about the climate are freely shared."

            "There's a fifty million dollar prize at stake," Palomino responded. "All the teams are very cautious. Besides, our sponsor is rather quirky, and I did not object to the use of encryption."

            "You explored the cave," Ben prompted. When the club got into Q&A mode, their initial formalities grew relaxed. "Using the base station as a relay." Easy enough to personalize the actions of the distant lunar rover.

            "Remember, this video is from our second entry, twelve hours ago." Palomino looked split between pride and utter frustration. "Mr. Auslander was generous, and we added every type of instrumentation possible. There really is such a thing as too much information, and without a working theory to tie our findings together, we are baffled."

            On screen, the rover rolled into the cave entrance. "Having secured the prize, we cut off our public releases, and leaked rumors we might have found valuable ore."

            Grayish rock narrowed the view as mounted spotlights came on. The passage, Leo noted, was about one meter high. He'd have to bend over, or with a spacesuit on, crawl.

            On impulse, Leo Watson called up a schematic of the rover. Its scoop extended toward the rear, while in front, dual round spotlights perched above forward stereo cameras. Below the two cameras, an imaging radar system was housed within a protective cone. Leo chuckled. The rover resembled a mouse.

            Palomino glanced his way, then on-screen she enlarged part of the wall. "These cut marks indicate this passage is artificial." Data scrolled below the image. "The rate of dust accumulation, along with isotopic dating of the outermost exposed surface, show the place is at least half a million years old."

            The rover moved again. About twenty meters in, the passage widened. What came next left Leo stunned. His first thought was 'hoax,' but the second became, 'intriguing mystery.' Several other Lunar Farside Challenge teams had rovers in operation, and three were still in flight. He figured that independent verification was needed, and might not be long in coming.

            As for the images before him, disbelieving Palomino herself was so far down Leo's list of emotional preferences that contrary facts would have to thrash him awfully hard.

            As if she'd read his mind, Palomino said, "I checked the raw telemetry myself, from two separate ground stations. I also sent the rover a few test commands, late last night, without telling anyone else. Whatever you choose to make of it, this is genuine data, from a quarter-million miles away."

            Unless, Leo realized, the whole scene had been prepared in advance. But, he argued with himself, who would bother spending hundreds of millions of dollars to fool a brilliant young selenologist? Who could accomplish such a thing without anyone spotting all the rockets and heavy equipment that would've been necessary to construct a lunar cave? Or the massive tracks left behind?

            Each ASK member focused on the images with greater interest. The underground room was rectangular, with smooth stone walls, except at the far end. Back there, reminding Leo of the Lincoln Memorial, the upper part of the wall was covered in writing. On both sides, at the far corners of the room, stood a matched pair of tripods. Atop each was a strange device, boxy with a round hole in the front. Whatever they were, each bore a thin coat of dust. They had not, Leo figured, performed any sort of function in ages.

            The rover's main camera zoomed in and panned the rear wall, examining three lines of writing, embossed on a hard flat surface. The dark symbols, a different script on each line, contrasted with the beige-colored surface underneath.

            Leo thought the writing looked vaguely familiar, like half-remembered images from a dream, or a story read in childhood. The symbols were high above the rover's limited vertical reach, and covered the ancient surface in three distinct rows. These reminded him of Chinese ideograms, Egyptian hieroglyphics, and perhaps Sanskrit.  

            If this was a hoax, it was outrageously elaborate.

            "I can imagine a rectangular natural cave, but are those tripod things for real?" Palomino asked. "Are those markings unknown languages? They resemble ancient scripts, but our people can't make out any meaningful words."

            Rabbi Rosenblum gasped. "It couldn't be!" With that, she dashed outside to her car.

            A minute later, she returned with a large bound folio. "An archaeologist I know sent me this information about the Mother Tongue." She opened it to a plastic-covered page.

            Leo noted a similarity between the characters in the folio and those on that faraway wall. Serendipity had dealt them another card, as archaeology and planetary science intersected at their meeting table.

            "The Mother Tongue is controversial," Rosenblum explained. "Two weeks ago, a large sample was found on the walls of a cave in Botswana's Kalahari Desert. Until then, no one knew the full extent of its written form. Not always easy to translate, but the words are ancestral to hundreds of human tongues."

            "How old is the desert cave's writing?" Ben Buridan asked Rosenblum.

            "About seventy thousand years," the rabbi answered. "But these lunar markings could be five hundred thousand years old! That means there must have been multiple visits by whoever created them."

            Rosenblum pulled out a sheet of paper. "Several uncatalogued symbols came to light yesterday, when my friend excavated a sand-filled chamber. I got a fax this morning." With a gentle touch, the rabbi traced each pictogram on her laptop screen. "I see four of those symbols here, on the wall's middle line. Good thing about neural-net computers, approximating their meaning so quickly."

            "Marvelous." Palomino was delighted. "If these unknown symbols exist on both worlds, there's got to be a lot more to this story. I've heard plenty of tales about hidden aspects of human history. My Zuni people have a long memory, and legends subject to fanciful interpretation."

            Palomino's smile brightened. "Now we might actually find a basis for some of those legends. What does the writing say?"

            "The carvings in Botswana are still being translated," said Rosenblum. "They're stories of trust and betrayal, of a great spiritual conflict, and an epic journey." The rabbi checked a printed list, then scribbled a few notes. "This could serve as a Rosetta Stone for the whole depth of history! As best I can tell, each of the three lines read the same: Wolf Star. Running Fast Paintings. Happy Watchers Gather. Hut Making Clan."

            An unspoken "Huh?" resounded from everyone else at the table. 

            The rabbi grinned. "In context? The Wolf Star is now known as Sirius, the Dog Star. This looks to me like a commemoration, a multilingual plaque, if you will. I'd render it colloquially as: Sirius Film Studios, Props Department."

            Kung shook her head, obviously perplexed.

            Rosenblum parsed it. "Sirius. Movies. Audience. Sets."

            "Movies?" Palomino exclaimed. "That is bizarre. Life imitates art, or something like that. Please, let's figure out every detail we can."

            As a climatologist, Leo was used to integrating data from far-flung sources. He'd experienced the ferocity of scientific controversies, and this discovery promised to make global warming look like a picnic. Barring a miracle, or some moral antithesis thereof, the cave had to be genuine. Even so, and despite himself, his eyes kept going back to the rover's odd-looking tracks.

            ASK specialized in doing a lot with a paucity of data, and ferreting out new angles from innocuous details. With a flash of understanding, Leo met Ben's eyes.

            "Jessica, your rover does chemical analysis, right?" asked Leo.

            "Yes," Palomino replied. If the question surprised her, she didn't blink.

            Ben spoke up. "Did your team do any analysis on that floor of that chamber?" The rover's initial visit had left faint tracks, scored with minor flaking, as with a dry lake bed rather than stone.

            "Probably," she said. "I'll send an urgent request to the mission science coordinator."

            Coordinator, singular, Leo noted. However well funded, this was definitely not a government operation. On impulse, he began a web search on Palomino's reclusive sponsor.

            Palomino set up a video link with a white-shirted man who simply radiated nerdiness. Eager to please his boss, the NASA veteran soon found the requested information.

            A screen icon flashed. "Thanks much." Palomino closed the link. "Here's the record of our analysis." She opened the file and passed it along. "Even that far underground, dust accumulates due to solar-electrostatic effects. The rover used its              shovel as a brush, and cleared dust to get a better sample. After that, the drill easily broke up the regolith. That floor isn't like any encountered before."

            "I took chemistry in premed," Dr. Kung said. "Those mini-lab chips are amazing. This looks to be a desiccated phyllosilicate substance. Most unusual." She began a search on her own laptop.

            "Phyllosilicates are more commonly known as clay," Ben explained.

            Leo took interest in another piece of data. "Its isotopic ratios don't resemble those found on Earth or the inner solar system." He went over the readouts again. "Maybe those Sirius Film people brought it there, to build some kind of movie set."

            How much material did they bring, a gazillion years ago? Leo mused. Enough to reshape that whole region of the lunar farside? The outer solar system had raw material to spare.     

            Kung said, "So, if it were hydrated, you could shape it? Make things?"

            "Sounds like it," said Palomino. "Must never have been fired into brick."

            Ben asked, "Are those images in natural color?"

            Palomino frowned. "The rover spotlights were an afterthought. Never thought we'd enter an artificial shaft! Can't vouch for the visual accuracy." She consulted her laptop. "Here we are, spectroscopic image analysis. The floor's color peaks at 5500 angstroms."

            Ben looked thunderstruck. "5500? But that's . . . " He burst out laughing.

            Leo slapped the table with both hands, and joined in Ben's laughter. At meeting after meeting, ASK tackled strange and even threatening mysteries. By comparison, he found it a joy to revel in such cosmic oddity.

            "Clay at 5500 is like . . . " Leo couldn't get it out.

            How in the hell did humanity end up with an old wives' tale about such a thing? Leo asked himself, and broke out in renewed mirth.

            Perhaps actual stories had been told to early humans, then leached of context by the passage of seventy thousand years. Leo knew he'd spend a lifetime wondering why those movie-making aliens had used such a substance to mold an entire landscape. 

            Palomino gave him a pleading look, and Leo caught his breath. "Thing is, 5500 angstroms is in the yellow-green section of the visual spectrum. Green clay! It's almost like the moon, your part of the moon, really is made of green cheese."

            "Green cheese?" Palomino doubled up with a fit of giggles. Finally she managed to add, "If they thought something that lame was funny, they really must be aliens."

            "Your people have prankster gods," Rosenblum said. "Coyote, for one."

            Palomino turned to the rabbi, and Leo thought she looked startled.

            "Of course," the Native American woman responded. "Also, in common with the Pueblo tribes, there are several clown Kachinas. Our oldest gods, the specifically Zuni deities, are more nurturing. Especially the Moonlight-giving Mother."

            "How fitting," said Ben.

            "Together those mythic demigods express the psychology of humanity, and perhaps that of some ancient aliens as well," Dr. Kung observed. "If anything, more clearly than does the better-known Greek pantheon."

            "Too weird," Ben said, with a solemn expression. "I can see why the public might conclude you guys are kooks. Fifty million prize dollars would buy a whole lot of clay—or cheese."

            Leo addressed Palomino. "I was already thinking, when you first showed us the cave, that other Farside Challenge teams could provide verification. Three rovers haven't landed yet, and could redirect to that region."

            "We'd have to be discreet," Palomino said. "Show their team leaders what we've found. Get some better orbital shots of the cave area." She closed her eyes, thinking hard. "Later, we'd hold a joint press conference."

            "You could follow SETI protocols," Rosenblum said. "As a framework, I mean."

            Kung asked, "Whose idea was it to land your team's rover in that specific area?"

            Leo could've sworn he saw a flash of hand-in-cookie-jar guilt in Palomino's eyes. It passed, replaced by a look of sheer relief.

            "We ran everything past a ton of criteria, held meetings galore, got recommendations from specialists." Palomino sighed. "But yeah, those specific coordinates were my own suggestion."

            Leo began to wonder how many other aspects of this fascinating tale remained unspoken. Certainly a fitting case for ASK.

            Rosenblum refreshed the image on her laptop screen. "Where is the rover at this moment?"

            "Parked inside the cave mouth," said Palomino. "Where it's within wireless range of the base station, and can still see back inside the chamber."

            "Can we get a live view?" The rabbi's voice bore a challenge of its own, and a renewed curiosity.

            "Sure, if I boost the signal power." Palomino sent a request to her control console at mission control. "It'll take a minute, with the distance and our encryption. Here we go."

            Leo asked, "Can you zoom the camera?"

            "Done," said Palomino. Without asking, she aimed the rover's stereo cameras at one of the ancient tripods, with their mysterious boxes on top. "Look!"

            One of the devices had moved, so slightly that Leo couldn't be certain, but it seemed to aim directly at the rover. If its round opening really was a camera aperture, then humanity's mechanical emissary sat in plain sight.

            Leo raised a hesitant hand, and waved at his laptop screen. "Um, hello?"

            "Are you certain?" interjected Ben. "Look at the angle of the spotlights. There's some reflection off the lefthand wall."

            "Oh." Leo felt deflated. "It's just shadows." He indicated the strange device. "Vibration from the rover's drill must've loosened some dust." 

            "Yeah, I see that." Palomino sounded very disappointed.

            "So," Leo pressed, "you had an idea of what might be found in this specific locale? Based upon what, a Zuni legend?" He allowed some incredulity to show.

            Palomino hesitated. "Sort of. You guys would not believe me, and even if you did, I've another reason to be careful."

            "A much more personal reason?" asked Kung. "As Naomi says, you can trust us." She nodded to the rabbi. "This is all going to come out sooner or later, and we could help you through the process."  

            Their guest shrugged, a gesture fraught with meaning. "You can tell them."

            "All right. Remember when I took a leave of absence, a couple of months ago?" Kung asked her friends. "Did some public service work in rural Alaska?"

            Palomino took a laminated photo from her purse, and handed it around. It showed a young Native American woman with a newborn baby.

            "Is this you?" Leo asked Palomino.

            "It's her twin sister Jennet," Kung supplied. "The clinic I worked at mostly serves Yupik and Aleut natives, so imagine my surprise when a Zuni woman showed up. A Coast Guard air crew member, no less, with husband in tow. Nine months pregnant, and rather skittish about medical tests and records."

            "For a reason!" Jessica Palomino declared. "Jennet doesn't want herself, and the baby, to become medical curiosities."

            Kung nodded. "I understand, and no doubt you have a similar dilemma. Unknown blood type? Empathic connection to the unborn child? More, no doubt, if I'd been able to do additional tests."

            With an effort Palomino unwound. "Thanks for doing only the necessary tests, and for making me the aunt of a healthy girl." This memory restored their guest's smile.

            "Fascinating," said Ben, "and much closer to home. The words ‘paradigm shift' pale in comparison."

            Leo's laptop chirped, indicating a completed data search. What he saw no longer surprised him. A similar 'bing' sounded from Rosenblum's computer.

            "Ms. Palomino," asked Leo, "how readily did your sponsor allow your choice of a landing site?"

            Rosenblum nodded. "Mr. Auslander, sole owner of Galaxcorp, makes Howard Hughes look like a social butterfly. He's not known as charitable, yet he took great interest in your lunar project." She displayed a copy of the team's original sponsorship contract. "He lays claim to any unusual discoveries, natural or artificial."

            Palomino checked the text. "He did?" Her eyes widened. "I hate legal gibberish."

            "Have you ever met him?" Leo was almost certain of the answer.

            "Once." Palomino thought back. "Just the two of us, at his mansion in Santa Fe. It was awful dark in his library room. I mean, I expected eccentric, but this was really something."  Her voice trailed off, then resumed, very faint. "He had regional lunar maps already prepared, and on top of the stack was my . . . "

            Atop the next table over, Schrödinger the cat awoke, alert to some unseen presence. With a hiss, the cuddly feline's fur expanded to remarkable size.

            At the bistro's entrance a coyote appeared, and slowly crossed the room. Schrödinger jumped down, and met the strange creature nose-to-nose.  

            Doubting his own sight, if not his sanity, Leo glanced at the others. Everyone was watching the unexpected tableau. When he turned back, a man stood there. A tall man with bushy gray hair, and in the dim light his irises looked yellow. The cat rubbed against his legs, purring.

             "Leo, Naomi, Ben, Nancy, meet my grandfather," said Jessica Palomino. "Assumed by many to be only a fable." She stood, and gave the old man a hug. "He likes to keep an eye on us rambunctious kids."

            How old is he? wondered Leo. How many worlds has this being seen? Tales about Coyote dated back thousands of years.

            Coyote pulled up a chair, and spoke without preamble. "I am not a newcomer like Auslander. Nor am I of the people who built the lunar memorial. They are far away, making a documentary on a strange race that lives beyond the Coal Sack nebula."

            The legendary being grinned, feral. "Auslander's interest is primarily mercantile, but he's not the big shot he thinks he is." He set a paternal hand on Jessica's shoulder. "Your discovery will indeed draw attention. Be cautious." His attention shifted to Rosenblum. "I expect ASK to help look out for my human family. Please use good judgment."

            With no further words, Coyote walked to the exit. At the last instant, though Leo was never certain, he vanished from sight.

            With a contented sigh, Leo closed his laptop, pushed back his chair, and set both feet on the table.

            "Now what?" said Palomino.

            "A typical ASK meeting, after all."