The Arrows of Time

Ramiro strained his tympanum. It was hard to distinguish it from the sound of the cooling system, but the gusts were sharper, rising and falling less predictably.

The altitude displayed on the navigation console dropped below one saunter. As Ramiro watched the wind whipping dust across the ground, he began to discern an almost perfect dark circle with a wide penumbral ring, straight below the camera. He would have sworn it was the Surveyor’s shadow, but that made no sense: the sun wasn’t overhead.

A warning appeared below the image: the ultraviolet glare scattered back from the ground was approaching unacceptable levels. Even though the engines’ beams were splayed out to the side – and the camera was counting photons emitted, not received – too much irradiation could damage the sensor. Tarquinia closed the protective shutter and the image turned black.

The altimeter kept working, timing slow infrared pulses that were making it down and back through the dust. Half a dozen strides above the ground, Tarquinia cut the main engines and switched on the air jets to cushion their fall. Ramiro had barely registered the plummeting sensation before the impact drove him hard into his couch. The jolt left him shaken, but when he moved slightly in his harness he felt no pain.

Tarquinia swept her rear gaze across the cabin. ‘Anyone hurt?’

‘I’m fine,’ Agata replied, and Ramiro and Azelio echoed her.

The view through the window was so dark that the pane might as well have been a mirror, reflecting back the lights of the cabin. Tarquinia redirected the time-reversed camera to a side-mounted lens; the image showed red dust swirling over the ground, darkening the sky and blotting out the horizon. The sight dragged Ramiro’s attention back to the sound of the wind on the hull; he could hear the difference as the visible signs of each gust rose and fell.

‘Is this just… weather?’ he wondered. ‘Like the home world?’ He’d read about dust storms in the sagas, but it was hard to know which parts of those stories were real.

Agata said, ‘I read a memoir by one of the first travellers, a woman named Fatima. She described the dust blowing around at the site of a rocket test, jamming all the clockwork.’

‘But it shouldn’t be harmful to people, should it?’ Ramiro had no idea how fast the wind would need to be blowing before the dust would start abrading skin.

Tarquinia swivelled her couch around. ‘I don’t expect so, but no one is going out for at least two bells. I want to be certain that the ground isn’t hot – and I don’t care whether or not Esilio thinks we’re yet to use the engines.’

Ramiro turned beseechingly to Agata, but she said, ‘Good policy. In Esilio’s terms, the engines’ exhaust came from the environment and entered the rebounders, so that’s violating the local arrow already. We should treat all these non-equilibrium situations as uncertain, and only assume that temperatures will be uniform when everything is settled.’

They passed the time checking the Surveyor for damage, but even the weakest points on the hull – their repairs along the Hurtler gash – seemed to have survived the landing intact. When Tarquinia ran out of things they could inspect – short of taking the engines apart and putting the rebounders under a microscope – they brought out some loaves for a celebratory meal, and Azelio took photographs to show his niece and nephew.

Two bells after they’d touched down, the instruments showed the hull’s external temperature to be no different from the cabin’s. No one challenged Ramiro when he finally moved towards the airlock.

He closed the inner door, then hesitated, gathering his courage. There was no need to use the pump – Tarquinia had already raised the cabin pressure to match the external atmosphere. He was wearing his helmet and cooling bag for protection from the dust; he switched on the coherer in his helmet, dazzling himself for a moment until he adjusted the brightness.

There was fine red dust covering the grey hardstone walls of the airlock. He hadn’t noticed it by the dimmer illumination of the safety light. He ran a gloved finger along the seal of the outer door, trying to find the point where it had been breached, but if there was a hole it wasn’t apparent.

It hardly mattered now; however the dust had entered, he was about to let in a great deal more. But as he began to turn the crank, the realisation hit him: it hadn’t come from outside. They must have brought it with them all the way from the Peerless, scattered invisibly throughout the craft, with a little more accumulating inside the airlock each time the inner door was opened. Or in Esilio’s terms: the Surveyor’s visit had just ended, and this residue was something they would soon take away with them.