# Death Star

(Spoilers for anything prior to end of chapter 89 of The Deathworlders: https://deathworlders.com/books/deathworlders/chapter-89-titanomachy/)

**Date Point: 25y2m13d AV**

Cairns, Australia, Earth

*Jo Lawrence, PhD, trying to relax*

Alpha Centauri had exploded.

![Supernova](supernova.jpg)

Stars like that weren't supposed to be able to explode, but of course the explosion hadn't been natural — it had been blown up as the last act of vengeance by the Hunters, their final strike against civilisation before the allied fleets had *finally* done the Dominion a favour by wiping them out.

"Bloody typical," Jo swore at nobody in particular, "First chance I get for a real holiday in two years, and this happens."

She switched off the TV and turned on her tablet. *Hundreds* of new notifications, mostly saccharine condolences from ET collaborators, expressing sadness about the impending destruction of her planet, four years from now when the light from the explosion finally reached the Sol system.

![Jo Lawrence, PhD](dr_jo_lawrence.jpg)

Jo shook her head with a frown. Such fatalism was hardly their fault: just as the Hunters had treated the bodies of every sentient race in the galaxy with even more contempt than a factory farmed chicken, the Hierarchy — the uploaded minds who were the power *behind* the Hunters — had treated the brains of all sentient life in the galaxy as a garden to be tended and weeded, and they had used neural implants to *trim* even the thought of being able to defend oneself so thoroughly, so completely, that even after Humanity had pulled back the curtains and shown the conspiracy, even after the neural implants had been taken away, it had still taken a *decade* to turn the ET fleets into anything more capable than Jo could've managed all by herself. That wasn't hubris on her part — she knew full well that any human who cared about war would outmatch her by an even larger margin than she outmatched the ETs, but at times like this she understood why some dismissed these well-meaning friends and colleagues as just "Squishy Xenos".

What Jo did know, and knew well, was physics. Even though she had only just learned of the explosion, she could see at least four different ways to deal with this, this… she snorted a laugh as the word "Death Star" auto-completed in her own inner monologue. The fictional battle station of that name was all kinds of nonsense, as the rapid physical disassembly of a planet would require roughly as much energy as a normal sun-like star would put out in six and a half days. As mass and energy were equivalent, she briefly wondered how much of a gravitational field that much energy would have by itself; a quick request to the voice assistant told here it was 2.5 trillion tons of condensed energy, which was more than all the biomass on Earth, but not enough for any human to feel by its gravity alone.

Distractions. These days, Jo found it was far too easy to get distracted, and that was why she had gone on holiday in the first place. Focus. Close eyes, breathe in, breathe out. Focus. Open eyes.

OK, so… how much energy had the Hunters actually sent this way, given it wasn't a natural supernova? The article was short of details; it seemed the AEC hadn't announced anything publicly yet, and all the details came from a privately funded probe studying the *Beta* Centauri system a few light-hours from Alpha Cen. Assume the entire star had been fused all the way up to Nickel-56… "Computer, calculate: mass Alpha Centauri divided by proton mass times seven em-e-vee"

The screen displayed "1.34103664×10^45 joules", far more precision than was warranted. Still, 1.35 to the 45, more than a type Ia, less than a GRB. Probably far more than enough to pop the Sol system shield, though the exact strength of system shields was *yet another* classified piece of information. Assume the shield blocked 99.9% of that, and what was left would *still* be six billion times more than enough to do to Earth what Peter Cushing did to Alderaan. In fact, even with 99.9% losses, that was enough to make *any* object inside the Sol shield — any planet, any asteroid, the sun itself — explode so violently that the Earth would be destroyed by that explosion. It was such a monumentally large energy that it hitting a small moon on the far side of Saturn or Jupiter would release enough energy into those planets that those planets would explode forcefully enough that the small fraction of them which reached Earth would still be enough to boil off not just Earth's atmosphere and oceans but also the entire crust and at least the first few hundred kilometres of mantle. More distant objects might only explode with enough force to merely render the planet uninhabitable even without the physical disassembly of the planet — it could probably hit any of hundreds of targets outside the System shield, for example Pluto, and enough of the flash of light from the exploding former-planet (in both senses) would probably be enough to sterilise Earth. So, don't rely on the system shield.

![Voice interface](VoiceInterface.png)

What next… well, the energy would only really be that focussed if the Hunters had some very interesting forcefield technology. But forcefield tech wasn't *magic*, even it sometimes felt that way: Thermodynamics meant that *de*focussing was much easier than focussing — Jo smiled ruefully that her increasingly skittish brain was just obeying a fundamental law of the universe — so, some fraction of the energy would be wasted even in the best case. Did that help? Not directly, but she could already see a way for focussing forcefields to help no matter what the Hunters had done. A warp-capable ship flying alongside the focussed explosion at *just under* the speed of light would be able to project a deflecting forcefield in the path of the beam, and power itself from the energy in that beam. But it would need to sweep the entire width of the death ray to avoid surprises from the Kuiper Belt and the Oort Cloud.

Jo looked at the stasis box and wondered if she should get a snack. Probably not. What was she doing, loosing focus already? She frowned, then realised her subconscious had given her another option! Stasis fields were completely black, as any light that went in became stuck in the slow-time field. Jo wasn't sure how much energy a stasis field could absorb — General Relativity suggested that enough energy in one place, even in the form of pure light, would become a black hole, and the maximum output of the Alpha Cen explosion would be a black hole with an 11 meter Schwarzschild radius. Perhaps industrial users made them that big, but she only knew about the domestic and medical uses, where they had largely replaced fridges and freezers and totally replaced cryonics. Jo tapped a finger idly on one of the many chat apps on her tablet, and saw there was a memorial serviced dedicated to the crew of the *Destroying Fury*. "Wasn't that the Great Father's ship?" she muttered out loud, "I thought he was still around?". Realising she'd lost focus again, she cursed herself, closed the chat app and deleted it from the tablet, and stood up. Then she realised that the jump drives that every starship was equipped with included a mechanism for generating a temporary stasis field around the ship itself, and almost every ship, possibly literally every ship, was more than 22 meters across, so even in the worst case scenario this was a totally viable option, or it might be if stasis fields worked the way she thought they worked.

What else… warp drive! Oh, it seemed so obvious now, but that was a ridiculous hack. Light was constrained to Einstein's rules of spacetime rather than the actual reality, so if this was a light-speed attack (and it certainly seemed to be), then all it would take to stop it would be spiralling around it with a warp capable ship. No need to *carefully* manoeuvre just under the speed of light to red-shift the death flash down for safety, just fly right through the thing. The photons would have an equivalent mass, but it would be no worse than picking up hull charge from interstellar dust.

Was there any other way to diffuse the energy? Jo thought for a moment, and quickly decided that there was not. Although any old boring matter could absorb most of the photons and safely re-radiate them in every direction (which was essentially what stars did normally if you *didn't* interfere with them with arrays of focussing forcefields), and although at this distance the largest possible isotropic explosion would "only" seem as bright as Sol (and Jo was sure that was well within the capacity of the system shield), a supernova was essentially the one and only source of *neutrino* radiation intense enough that it could give you cancer. Sure, you would normally have to be *inside* an exploding star to get that lethal dose even then, but that was only true of natural explosions: if this weapon was designed with that in mind, merely diffusing the bolt of electromagnetic energy somewhere near its source would do no good at all.

Then there was the possibility of evacuation. Jump terminals had mostly, but not completely, replaced flights, and interstellar was as easy as the trip here from Zürich: go to a small room, wait for a few minutes, and when you feel a deep thump then you've arrived. Even pure tourism moved enough people each year to evacuate the whole Earth before the light of the supernova reached them, and there was plenty of cargo transport too, probably enough to save a significant fraction of the flora and fauna of the planet. But that would only work if humans had a place to *go*, not just a way to get there, and there weren't so many good planets for humans. Well, no, that wasn't true, almost *every* planet was great *for humans*, but humans weren't great *for those planets*. Jo looked out of the window; it was a built-up area, but even just lining the pavements with palm trees made it closer to jungle than she was used to. Australia had always, at least in her lifetime, had a reputation for being the place where evolution had driven the wildlife to extremes of having toxins and poisons and resistances to the same, and Earth was that to the majority of life-bearing worlds in the galaxy. So much so, that the Dominion had infamously refused point-blank to accept that so-called Deathworlds like Earth could harbour sentient life, even after a pre-contact abductee, a random Texan bartender, had first made waves by literally beating a small team of Hunters to death with their own arms.

There might be a way to move the entire planet, too. She wasn't sure if a jump-drive could be made that big, but if the death bolt was only focussed on Earth, then you could move the Earth by moving the Moon… but perhaps not. The barycentre of their combined orbits was still inside the Earth, and moving something as big as the Moon came with far too many other risks.

Hmm. Didn't that friendly von Neumann swarm, an un-ageing brain scan of some celebrity or other from before they were famous, say she'd built a garden in a space station? What was her name… if only Jo could remember the entity's name. Or the name of that celebrity. Or even what she was famous for, that would help. The tablet pinged a notification from the ESNN app, Jo rolled her eyes at the distraction, swiped, and congratulated herself for dismissing the notification without reading it. Regardless, whatever that entity was known as, unless it had been completely destroyed by the flight with the Hunters, it could almost certainly build enough space stations to house all of humanity, and probably a significant fraction of the rest of the life on Earth too.

And of course, if that girl was uploaded, everyone else could be too. Likewise all the other species. Jo liked that idea; perhaps if her mind was software, she could edit away her lack of focus. Then again, perhaps she'd get distracted part way through the task…

And just then, a new message notification arrived from a different chat app and distracted her again.

Based on Deathworlders (© Philip Richard Johnson), Attribution-NonCommercial-ShareAlike 4.0 International
https://github.com/deathworlders/online/blob/master/LICENSE
https://deathworlders.com/books/deathworlders/