The Astrophage Budget
One declared miracle: a cell that banks energy as mass, at 99.9% of the antimatter rung. Granted once. Then the audit: three of the book's numbers lock into one to 0.11%; its farm year balances to within its own phrasing; its quiet eight grams obey a reactor's E = mc² ceiling. And three clocks disagree by ×430 until a 0.21 MJ dial reconciles them, while the desert plan draws 208% of the real Sahara's sun. Both verdicts, equal size.
Open the interactive ▸ What you are looking at
The Curve is the dimming timeline on a log axis: the book's own printed curve in gold through its three stated points, the lab's 8-day clock and the 9.6-year full-charge gate as dashed brackets, and in crimson the curve made by the one dial the novel never turns: how much energy a cell gathers before each breeding trip to Venus. Presets land the dial on the book's two implied legs (0.21 and 0.74 MJ), the 1.8 kJ biology floor and the 1.5 MJ full tank. Tabby's Star, the one real star famous for dimming, can ride along from INST-21's numbers.
The Budget prices the dimming you dial in: the power withheld, the mass banked per second, the covering population and its dry and charged tonnage, the Hail Mary fuel loads it holds, every row derived from a covering fraction and a cross-section. Beside it, the energy-density ladder from lithium-ion to antimatter, with the charged cell sitting at 99.9% of the top rung. The Line flies the Petrova line in 3D at true scale: the 37-million-km climb, the bend, the funnel to Venus, the migration running both ways at 0.92 c, and the clearance geometry the climb buys, with the ribbon's exaggerated width labelled on the view.
The Farm audits chapter 5's breeding year on a log-mass axis: 150 charged seeds doubling every 8 days, the book's 173,000 kg marker, the dry-seed ledger that yields only 166 kg, and the knee where every exponential dies: the power ceiling, drawn for a carrier reactor, the book's round-the-clock Sahara and the real one. The File lays every claim on a card (PASS, CATCH, or the bench's own additions) and hangs two verdicts at equal size.
Why it is here
This site's culture wing carries a signed review of Project Hail Mary, and the review leans warm: Weir grants himself one impossible premise and then pays full price for its consequences. But the shelf's rule is the rule: numbers stated with confidence get priced, fiction included; the precedent is INST-59, which priced the mothership of Dead Dead Demon's Dededede Destruction. And this novel states more and harder numbers than any UAP book on the shelf: a microbe at a constant 96.415 °C that absorbs every wavelength and emits at 25.984 µm, doubles in 8 days, cruises at 0.92 c, and banks 1.5 MJ as 17 nanograms of mass; a Sun 0.01% dim at detection, 1% in nine years, 5% in twenty, half of everyone dead in nineteen. The whole novel (the coma, the coercion, the desert) hangs on these figures.
It is here because those figures can actually be run, and the audit cuts both ways. One way, the prettiest lock on the whole shelf: the kinetic energy of a thermal proton at 96.415 °C, the energy of one 25.984 µm photon, and a neutrino at 'one twenty-billionth the mass of a proton': three numbers from different chapters that turn out to be one number, to 0.11%, and a neutrino mass that fits under KATRIN's and Planck's real bounds. The other way, three clocks that disagree: at the lab's 8-day doubling the Sun is shrouded in 106 days, and the 'exponential' curve as printed is really two legs of 1.35 and 4.74 years. The bench puts both on the table: the fiction-pricing line's second instrument, a neighbour to Tabby's Star (INST-21) and the technosignature bench (INST-45). The verdict is not made for you, but the arithmetic is all on the table.
How it works
Everything on the bench is closed-form arithmetic on the novel's stated numbers plus physical constants: a covering fraction, a cross-section, E = mc², the photon-rocket equation, Planck's law, a doubling. The script that ships with the site re-derives every displayed number before the build passes.
N = f·4πR☉²/σ · dM/dt = P/c² · t₂ = E_depart/(F☉σ), floor 8 d · k = √((1−β)/(1+β)) = 0.204 · L_line = (1−k²)·f·L☉
The swarm. N cells of cross-section σ = 78.5 µm² cover fraction f of the photosphere; they withhold f·L☉ and bank it as mass at P/c². Dry mass is N × 20 pg; charged, N × 16.7 ng, the 1.5 MJ tank the book states, converted once by c².
The clocks. Every division requires a Venus trip; a covering cell intercepts F☉σ = 4.94 mW. A departure charge E therefore sets the doubling time E/4.94 mW, floored at the lab's 8 days. The book's milestones invert to 1.35 and 4.74-year doublings: 0.21 and 0.74 MJ on the same dial.
The line. A photon-propelled boost to 0.92 c keeps k = 20.4% of the traveling mass, cargo irrelevant; one cycle (out, breed, both back) emits 1−k² = 95.8% of what departs, all at 25.984 µm. The Sun's own output in a 1% band at that wavelength comes from Planck's law: the line outshines it ×7,400 at 1% dimming. The climb geometry is triangles: one solar radius already clears the far orbit; 37 M km clears it ×53.
The farm. 150 charged seeds double every 8 days until the ceiling M·ln2/t_d = P/c² bites; past the knee, growth is linear at the ceiling's dM/dt. Three ceilings are drawn: ~1 GWt (a carrier reactor: 0.96 g/day), the book's Sahara (1,000 kg/day, a 24-hour sun), the real Sahara (481 kg/day).
Nothing is tuned for the book and nothing against it: where its phrasing allows slack ("just over eight days"), the bench rounds in its favour, and where its numbers lock, the bench says so at the same volume as the catches.
The dials that decide the outcome
A departure charge, a dimming fraction, a clock of years, four cameras, a desert sun. Together they draw every schedule on which the novel's Sun can die, which is itself the exhibit.
- Departure charge. 1.8 kJ (a daughter's mass, the floor where biology's 8 days rule) to 1.5 MJ (the full tank, 9.6 years per doubling). Presets: the full tank, the book's two implied legs, the floor.
- Years since detection. 0 to 25, with the cursor reading both your curve and the book's at once.
- Overlays. The book's printed curve, the lab clock, the full-charge gate, and Tabby's Star from INST-21.
- Dimming priced. 0.01% to 100%, log; presets at detection, the two milestones, the 10% shelf where infected stars stop, and full shroud. Every Budget row and the line's luminosity follow it.
- Cameras. The whole line, the pole close-up, the funnel at Venus, and edge-on, the seat Earth watches from. Toggles: the migration flow, the clearance geometry, labels.
- The farm. The real Sahara sun against the book's round-the-clock one; the dry-seed ledger on or off.
Where the claims stand
Nine of the novel's stated numbers, and where each lands when the bench runs it: checks, conditions, and misfires at the same volume.
| A cell stores 1.5 MJ as ~17 ng of mass; the drive burns 6.045 g/s at "540 trillion watts" Stated in ch. 5, 6 | CHECKS | E/c² gives 16.69 ng and 543 TW. Both of the book's figures are real conversions, correctly done. PASS. |
| 96.415 °C, 25.984 µm, a neutrino of one twenty-billionth of a proton Stated in ch. 4, 1, 13 | CHECKS | One number three ways: 47.77 meV (thermal proton), 47.72 meV (photon), 46.91 meV (the stated neutrino), locked to 0.11-1.7%, and inside KATRIN's 450 meV and Planck's 120 meV bounds. The book's showpiece, verified. |
| 150 cells become 173,000 kg in a year, 2×10⁶ kg a month later Stated in ch. 5 | CONDITIONAL | At the 8-day doubling with charged seeds: 139,000 kg, i.e. the book's figure at a 7.94-day doubling, inside its own phrase. But dry seeds give 166 kg: the ledger balances only if every cell stays charged, which makes the farm a power problem the book only half-acknowledges. |
| The Sun dims 0.01% → 1% in 9 years → 5% in 20, "exponential" Stated in ch. 2 | MISFIRES | The two milestones imply doublings of 1.35 then 4.74 years, not one exponential, while the lab clock (8 days) would shroud the Sun in 106 days and a full-charge gate would take 64 years to reach 1%. Three clocks, ×430 apart, never reconciled in the text. One departure-charge dial (0.21 MJ) repairs the first leg. |
| The blackpanel banks 0.5 µg/m²/day under "1,000 W/m²" Stated in ch. 13 | MISFIRES | That is 4.5×10⁷ J/day: 52% of a 1,000 W/m² sun shining 24 hours, and 208% of the real Sahara's ~6 kWh/m²/day. The desert plan is over unity on a planet with night. At the book's own 1,000 kg/day, the tank still takes 2,000 days. |
| Grace makes "only eight grams" on the carrier Stated in ch. 5, 9 | CHECKS | A ~1 GWt reactor can enrich at most 0.96 g/day, by E = mc² alone. The novel's quietest number is exactly right, and it is the reason the Sahara exists in the plot. PASS. |
| The Petrova line climbs 37 M km off the pole "or the sun would be too blinding" Stated in ch. 1, 5 | CHECKS | One solar radius of climb already clears the whole Venus orbit past the limb; 37 M km clears it ×53, shrinks the Sun to 1.08° and keeps Venus ≥71° away. Stated reason, sound geometry. PASS. |
| The line is "very faint" from Earth Stated in ch. 1 | CONDITIONAL | Priced by the bench: at 1% dimming the line carries 3.7×10²⁴ W at one wavelength, ×7,400 the Sun's own 25.984 µm output, but beamed along the migration axis, so off-axis Earth sees only dust-scatter. Consistent; and it makes every infected star a monochromatic beacon to anyone downrange. → INST-45. |
| A dimming star is what an Astrophage infection looks like Stated in the bench, for INST-21 | READING | The real dimming star, KIC 8462852, fades chromatically (dust-like) and shows no 25.984 µm line. An Astrophage shroud would dim grey and scream in the mid-IR. The mechanism is a testable third setting on INST-21's dial, and the sky has already voted. |
Try this
- Start on The Curve. Gold is the book. Press "The biology floor": the crimson curve goes vertical: the Sun is gone in 106 days. Press "The book's leg one": 0.21 MJ, and the crimson curve lies down on the gold through nine years. One dial, one novel repaired.
- Open the three-clock card (top right of the plot). 8 days, 1.35 years, 4.74 years, 9.62 years: the same organism, ×430 apart.
- Go to The Budget. Read the ledger at 1%: 42,600 tonnes a second, 7.7×10²⁶ cells, 15.5 Gt dry. Tap the Astrophage rung on the ladder: 99.9% of antimatter.
- Fly The Line. Press "The pole": watch the climb. Press "Edge-on": this is roughly Petrova's seat, and the line all but vanishes, which is the point. Tap the bend for what it carries.
- Go to The Farm and flip "The real Sahara sun". The knee drops, the tank date slides from 2,000 days toward 4,160, and the ceilings card shows the blackpanel running at 208% of its light.
- Finish on The File. The lock, the eight grams, the three clocks, the desert, then two verdicts at equal size. The review said the homework shows; the bench shows the homework.
Accuracy
The honest line between the book's words, the bench's arithmetic, the real world's measurements, and the reading:
| Feature | Status | What it means |
|---|---|---|
| The novel's numbers | Reported | Temperature, wavelength, doubling time, milestones, tonnages: quoted with their chapters (Penguin 2022 paperback) and treated as claims. Nothing is silently corrected. |
| Every conversion | Exact | E = mc², kT, a photon's energy, the covering population, the photon-rocket equation, the doubling arithmetic, the desert power ledger. Re-derived by the tune script before the site builds. |
| The real world's side | Measured | Tabby's Star (the numbers INST-21 draws: Montet & Simon 2016, Boyajian 2016/2018), KATRIN's and Planck's neutrino bounds, the Sahara's ~6 kWh/m²/day, world energy use. |
| The line's luminosity, the reactor, the ribbon | Modelled | The Petrova line's power assumes the stated migration cycle (95.8% of departing mass emitted); the carrier reactor is an order-of-magnitude 1 GWt; the 3D ribbon's width is exaggerated for visibility and labelled so on the view. |
| What it amounts to | Reading | Whether a novel that locks three numbers into one but keeps three clocks that disagree earns Reading A (the homework shows) or Reading B (the price list has footnotes) is yours to decide; the bench prints both at equal size. |
One line: Every number on the bench is either the novel's own claim quoted with its chapter, a closed-form conversion re-derived at build time, or a published measurement standing in for reality; the only modelled pieces (one migration cycle, one reactor, one ribbon width) are labelled where they appear. The reading is yours.
Sources
- Andy Weir, "Project Hail Mary" (Ballantine 2021; Penguin 2022 paperback): every claim priced here, quoted with its chapter: the temperature and wavelength (ch. 1, 4), the milestones (ch. 2), the doubling time, cell mass, 0.92 c, the breeding year and the 10²³ J (ch. 5), the 540 TW (ch. 6), the neutrino mechanism (ch. 13), the blackpanel and the Sahara (ch. 13).
- CODATA 2018 constants and IAU nominal solar values (L☉ = 3.828×10²⁶ W, R☉ = 6.957×10⁸ m, T☉ = 5772 K): every conversion on the bench.
- B. T. Montet & J. D. Simon, ApJL 830 (2016); T. S. Boyajian et al., MNRAS 457 (2016) and ApJL 853 (2018): KIC 8462852's secular fade, dips and chromaticity, the numbers as INST-21 draws them.
- KATRIN Collaboration, "Direct neutrino-mass measurement based on 259 days of KATRIN data" (2024): m(νe) < 0.45 eV. Planck Collaboration 2018 + BAO: Σmν < 0.12 eV. The real bounds the invented 47 meV neutrino must clear.
- Global Solar Atlas / World Bank: central Sahara global horizontal irradiation ~6 kWh/m²/day, the real sun the blackpanel is priced against.
- This site: the Mothership Ledger (INST-59, the fiction-pricing precedent), Tabby's Star (INST-21), the technosignature bench (INST-45), and the signed review of Project Hail Mary in the culture wing.