In roughly five billion years, the Sun will explode and consume the Earth. Dust will not be lucky enough to escape, let alone chunks of debris. There will, in short, be nothing left.
This isn't frightening. We'll be long dead, or escaped.
It's the dead part that interested me. Obviously we'll have long since rotted to dust, or have been burned to dust, or will burn to finer dust when the solar crematorium gets cooking.
So this set me to thinking. So far, there's two major theories as to what happens when you die. Either there's nothing - you'll be nothing, as you were before you were born. That wasn't so bad. I don't recall being very uncomfortable in the 250,000 years before I struggled into the light.
The other is the supernatural theory - you go to some sort of paradise or unimaginable torment, or into a cosmic waiting room in which you expiate your sins before starting your eternal stint upstairs or downstairs. More worrying, but not hugely plausible.
No-one really thought of the third option.
So I lived out my years. No-one was less exceptional than I was - normal and unworthy of note in every possible way. I was born, educated, worked, married, sired children, raised them, retired.
And, of course, I died without fuss or ceremony on a Tuesday morning. It was raining, and had been since six. I died at eight.
It was still raining at nine.
I had a coughing fit - nothing new there, they were pretty normal. It settled down, and the fluid that had come up my throat subsided. Then the doctor - young, younger than they used to be, and as tired as I'd ever seen anyone - put the stethoscope on my chest wearily and announced 'he's gone'.
Well, it came as something of a surprise. At first I thought he was mistaken - young, maybe inexperienced - but then a battleaxe of a duty nurse jammed two calloused fingers to my neck and nodded briskly. 'I'll send an orderly up in a few. Call it and do the paperwork, I want a bag'
By now I was anxious, and decided to point out as politely as possible that there'd been a mistake and I was still very much alive and conscious. Still, it actually didn't come as much of a surprise when I couldn't speak.
I knew immediately that I wouldn't be able to move my limbs. Still I tried. Immobilised totally.
Panic began then. I was paralysed, some disorder had taken hold, they'd mistake me for dead and bury me!
My mind raced. This happened, I'd read about it in papers and seen it in films. I'd wake up in a morgue drawer, or on the embalmer's table or - here I was literally blinded for an awful second with terror - a grave.
But no, that couldn't be it. I was conscious. Nothing had changed. I was just paralysed.
I lay. I watched the clock on the opposite wall and listened to its rhythmic tick. Rain pattered against the window.
Activity, at last. Figures in scrubs appeared, manhandling me off the sheets and onto a gurney. A sheet was thrown over my face and I was moved, moved, downwards. A bang told me I had been consigned to a morgue drawer and the panic returned, but with no physical outlet - thrashing or screaming - it merely sat like weights on either temple.
After what seemed like an hour, but may in reality have been mere minutes, I realised I hadn't been breathing for a while. I didn't know exactly how long. Think of waking up in a different position to the one in which you went to sleep and you'll have the idea - a change that you can feel but not remember happening.
I realised with an odd calm that I wasn't breathing, and didn't feel the need to, because I was dead. This is what happens when you die. Your mind goes on. I wasn't sure for how long, but clearly for quite a while.
Time went on. I was moved, embalmed, and placed in a coffin. Not one of these did I feel physically. Have you ever been powerless to prevent some harm befalling you or others? Every fibre straining to avert some disaster and total impotence to do so. It's really most odd.
I still wasn't frightened of much of this. I was even calm when the distant voice of my wife in the funeral parlour's office to my left elected, amidst dry sobs, for an open coffin.
So I tolerated this. I tolerated watching the face of everybody I'd known, racked with grief, looming obscenely over me as I watched the flickering bulb in the halogen lighting strips in the parlour ceiling. I was even able to smile inwardly as I watched my brother-in-law, with whom I had feuded for the best part of forty years, force crocodile tears out of loyalty to my sister.
I was really only frightened of two things. The first was being buried - that thick darkness as some disinterested undertaker closed the lid, and the percussive, heart-rending thuds as it was nailed down.
The second was dying forever.
I sure as hell wasn't living forever - I'd been dead since eight on that Tuesday morning. I hadn't breathed, blinked, even moved since then. But I felt exactly the same.
So they buried me, and it was every bit as terrifying and awful as I'd feared, and much more besides. But, as ever, there was nothing I could do. I watched as the final chinks of light around my vision were extinguished, without even the desperate hope of the prematurely buried that somebody - anybody - would realise their mistake and release me.
I couldn't tell you how long I've been here. At first, once I'd grown accustomed to lying in darkness with just my own thoughts, I even had the crazy idea that I'd be able to communicate with others buried near me. I guess I dredged up the idea from this Dostoyevsky story I'd read in university - Bobok, it was called.
I assumed this was what happened to everyone after death. There was no reason I should be unusual, or have been singled out for this end.
Anyway, I couldn't talk to my fellow buried. It was just me.
I'm fairly sure it's been years, or even decades. I can't be sure. Imagine closing your eyes, lying in perfect blackness, with no reasonable chance of anything intruding on you. Try it if you have your place to yourself. A few minutes and you'll be restless. A few hours and you'll fall asleep, if you haven't moved. I haven't slept. Not so much as a second. My internal monologue is never-ending. But I have hope. I've convinced myself my internal monologue is only going on because I have earthly remains. A body, even a decomposed one. Then bones. Then thick dust.
In roughly five billion years, the Sun will explode and consume the Earth. Dust will not escape, let alone chunks of debris. There will, in short, be nothing left.
I've been dying forever. Now curl your toes and enjoy that sensation. It might be small, but you'll find out how exquisite it is.