Monumentum Requiris

By johnnedwill

Officially it was listed as ETA-01 - Extraterrestrial Anomaly Number 1 - but everybody on Proxima Centauri-b just called it 'Downtown'. It had been spotted by one of the Icarus probes on a flyby through the system at just under one percent of the speed of light. The probe had confirmed the presence of planets in the Proxima Centauri system, and had noted that the planet closest to the star had a strong magnetic field and an atmosphere. It had also had time to record irregularities in the planet's magnetosphere. So, when the first expedition was sent to Proxima Centauri-b, one of the main objectives of the mission was to investigate the strange readings.

Downtown was a geometrical array of matt-black blocks on a plateau. Everything about the location pointed towards Downtown being artificial in origin: from the smooth, level surface of the plateau to the actual blocks themselves. The smallest of the blocks was a cube just over forty centimetres on each side, while the largest was a monolith almost a hundred and twenty metres tall. According to the surveyors who had first investigated Downtown, there were a limited number of different blocks, distinguished by each type being twice the volume of the next smallest type. There was obviously some significance to this geometrical relationship between the blocks; but, since the original builders were no longer around to tell us the reasoning behind Downtown, we had no way of knowing what that significance was.

Successive studies had been able to determine a few facts about the blocks. The blocks remained at a constant temperature of 77 Kelvin - the boiling point of liquid nitrogen at 1 bar. Each block also emitted a magnetic field that was strong enough to affect our instruments. The fields from adjacent blocks would sometimes synchronise with each other and resonate, increasing the overall magnetic strength. We had tried taking material samples from the blocks to see what they were made of. However, our hardest probes failed to even scratch the surfaces of the blocks. Even a plasma cutter could do nothing more than momentarily raise the surface temperature of a block, creating a hotspot that rapidly cooled as soon as the plasma was shut off. Based on this, one of the expedition physicists did a quick and dirty calculation and announced that if we could somehow bring the mothership down to within ten kilometres of the surface and focus the exhaust from its drives on one of the larger blocks, we might be able to vapourise its surface layer and maybe - maybe! - expose its inner workings. However, as the resulting fallout and radiation would render our surface base uninhabitable, we decided that this was not a good idea.

All of this investigation, calculation and speculation was no use in answering the burning question: what was Downtown for?

Of course, there were plenty of other things to occupy us on Proxima Centauri-b. Atmospheric composition, geology, weather patterns, the presence (and absence) of lifeforms. When it became obvious that we were not going to progress any further with our investigations into ETA-01, personnel and resources were shifted away from Downtown and onto other, more promising projects. A few technicians were kept to monitor the instruments that had been left behind in Downtown, but even this was considered a waste of time.

Proxima Centauri is a flare star - unpredictable and capable of emitting deadly levels of radiation. As part of their duties, the astronomers on the mothership had the job of monitoring the star for any changes that might indicate a flare was going to occur. The atmosphere and magnetic field of Proxima Centauri-b provided some protection to those of us on the surface; but if a sufficiently violent flare was predicted, there was a drill we had to follow. The mothership would send an alert and all personnel would retreat to the base and go to shelter stations. Equipment that might be affected by the flare would be brought into the base. Any equipment that couldn't be moved would be covered in protective shielding to ride out the flare. Then, when the radiation levels had dropped sufficiently, normal operations would resume.

We had been on the surface for just over three months when the crew on the mothership contacted us with a warning. "The primary is showing signs of an imminent flare. We estimate that the flare will occur in two hours - give or take. Everybody should be under cover within one hundred minutes to avoid the effects. According to the disturbances in the star's chromosphere, this one is going to be a big one."

The emergency plan went into effect. A message was sent out to all personnel on the surface, telling them to come home. External systems were disconnected; circuit breakers were tripped to prevent energy surges from damaging delicate electronics. We retreated to our storm cellar and hunkered down to wait for the flare to burn itself out. It was only during this period of relative peace that we realised something had gone wrong.

Anil Mistry had been taking the roll, making sure that everybody was accounted for. He came to the bronze command centre with bad news. "Petersen's missing. I've asked around, and nobody saw her come in."

As I was the bronze command for the day, I was the one ultimately responsible for the safety of the expedition and its personnel. I checked the rota. "According to this she was supposed to be in Downtown, carrying to maintenance on the remote sensors. She should have had plenty of time to come in."

I called a meeting of the department heads. We all agreed that our options were limited. If a search of the base couldn't locate her, then we would have to assume that Petersen was still out on the surface. By now, given the strength of the flare, she would have absorbed a fatal dose of radiation. However, we couldn't confirm this until it was safe to send out a search team. we couldn't even send a message to her as the storm of charged particles from the flare was making any communications impossible. All we could do was wait - and hope that Petersen had somehow managed to find somewhere where she could ride out the flare. Every ten minutes we sent out a technician with a Geiger counter to monitor the radiation in the base. As soon as the radiation levels dropped to something 'tolerable', I organised a team of volunteers to look for Petersen.

When we got outside the base, it was obvious that Proxima Centauri was still flaring. The sky above us was filled with green and blue streamers of flame - a sign that the planet's magnetic field was absorbing some of the particles ejected by the red dwarf. Sudden squalls appeared to buffer the purple fan-like organisms that passed as the local equivalent of plant life; but all we could feel inside our environment suits was the cool breeze of the air conditioning.

Santieri, our bioscientist, gaped in amazement at the dark flowers that had appeared in the centre of each cluster of ferns. "They must be absorbing the energy from the flare," he announced. The interference from the storm added layers of static and echoes to his voice.

"You can look at those later," I told him. "Right now, our priority is finding Petersen." I didn't want to face the fact that Petersen was most likely dead or dying from radiation sickness.

We made our way to Downtown. From a distance it looked beautiful, the colours of the sky reflected in the blocks. Once we were among the blocks everything was bathed in the strange light of the aurorae, dazzling us and making it almost impossible to see where one block ended and another began. We stumbled through the maze of Downtown, checking every shadow for our lost comrade.

Santieri held up a hand to call for attention. "Hey!"

"What?"

"My dosimeter - it isn't registering!"

This was ... unexpected. With the solar flare still bathing us in the eerie light, there should have been some radiation. "Check it," I told him.

Santieri fiddled with the box on his wrist. "It's working, but it's not reading anything."

"Right. Right." I thought for a minute. "Everybody - check your dosimeters. And somebody check the radmeter as well."

We all checked our instruments. Everybody's dosimeter was telling the same story: no radiation. The radmeter had a test source, so we checked that. Our dosimeters were working. It was just that there was no radiation here.

"Alright." I forced back the note of panic in my voice. "Let's worry about this later. We still have to find Petersen and get back to the base. Let's go."

We made our way to the heart of Downtown and split up into pairs, the better to search for Petersen. It wasn't long before we found her. She was standing in front of the largest block - the one we had nicknamed 'Grand Central'. She was still alive! And her dosimeter was still in the green! Of course we had questions, but we didn't know whether Proxima would start to flare again. So, we hurried back to the base. It was only when we were safe in the storm cellar, with the doctor taking blood samples, that I asked Petersen what had happened.

Petersen began her explanation. "I was checking the sensors around the centre of Downtown. You know, making sure that they didn't need anything doing. I'd been there for about an hour when I saw the aurora start. I hadn't heard any flare warning, but I knew that I had to get under cover somewhere - fast. I hurried out of Downtown, hoping that I could get to the base before I caught a fatal dose. But, the further I got away from the centre, the more my dosimeter started to register. I was scared, so I headed back to Grand Central. I guessed the blocks were having some kind of shielding effect." Petersen grinned. "I guess I was right.

"As the aurora got brighter, things got kind of crazy. The blocks started to turn different colours; then it looked they were blurring. It was just surreal. I thought it was just my eyes playing tricks on me, and I saw ... ." Petersen stopped.

"Saw what?" I prompted her.

"Ghosts," Petersen said in a quiet voice. "I saw ghosts. It was as if they had stepped out of the blocks. They were everywhere. I watched them until the flare died down. Then they just faded away." She looked at me. "You think I'm crazy, don't you?"

I didn't think she was crazy; but I couldn't believe what she had told me. So, I ordered a review of the data from the sensors in Downtown. Unfortunately, whatever had shielded Petersen from the effects of the flare, whatever had caused her to see ghosts had also blanked out the sensors. All we got from them was random noise and meaningless static. When the doctor came back with the results of Petersen's medical, the only thing that was wrong with her was elevated levels of stress hormones.

Naturally we needed to find out what had happened in Downtown. We could wait for another flare, but we didn't know how long it would be until the next one. Besides, I couldn't ask for volunteers to be on the surface during a storm. It would be too dangerous. We discussed whether or not we could replicate the conditions of the flare, but couldn't think of anything until somebody spoke up.

"You remember that crazy idea for using the mothership to try and crack the blocks?" "You mean the one where we all die from radiation poisoning?"

"That one. What if we were to dismount one of the particle beam emitter arrays from the drive unit, bring it down to the surface, then use that to reproduce the effects of the flare? We can tune the particle beam so it matches the flare's spectrum, then fire it at the blocks. Worst case we destroy the blocks. Best case we learn something new. How about it?"

It was a stupid idea - and a brilliant one. Somehow we managed to persuade the crew of the mothership to lend us one of their spare particle beam arrays and to bring it down to the surface. Then we had to set the array up on the plateau and run a line back to our power station. It took another ten days of hard work before we were ready to carry out the experiment.

We had no idea what would happen when we turned on the particle beam; nor did we have any idea whether our instruments would record anything. However, there was no shortage of

volunteers willing to act as observers. I pulled rank to be one of them, and insisted that Petersen was part of the group. She was the only one of us who knew what to expect.

The crack of ionising air announced the activation of the particle emitters, and a pencil-thin beam of ghostly light played over the surface of the target block. We had chosen one that was big enough to absorb the energy from the beam without too much damage - just in case. At first nothing happened, apart from the reading on the radmeter ticking upward. Then it stopped, and the surface of the block began to flicker and become insubstantial; changing from matt black to a misty grey.

"This is what happened," Petersen whispered. "Any second now ... ."

Almost as soon as the words had left her mouth, a hazy figure materialised in front of the block. It was featureless, with indistinct limbs, just over a meter and a half tall. As more energy poured into the block, the figure become more solid, more real. We could make out limbs that had alien proportions, features that would haunt our memories forever. We watched, fascinated at what was appearing before us.

Our headphones began to howl and the particle beam started flickering. The radmeter had enough time to scream a warning before there was a blue flash that seemed to go right through my visor. Then there was silence and only the dim light of Proxima Centauri. The target block had returned to its original matt black, and the mysterious figure had vanished.

I realised that I had been holding my breath. "Did we just ... ?" My voice trailed into a stunned silence.

"That's what I saw," Petersen said. "Exactly what I saw. The ghosts. Now do you believe me?"

I stepped forward to examine the block, to see if there was any sign of what had happened. Its surface was unmarked. I reached out to touch the black monolith. Even through the gloves of my environment suit I could feel the chill of 77 Kelvin seeping through the material.

Instead of answers, I only had more questions.