Corrections

When we get a number wrong, we fix it here and on the page where it appeared. We don’t edit quietly and we don’t backdate.

Each entry: date · study · what was wrong · what it is now · why · link. Newest first; entries are never removed.

  • Corrected · Galactic Center distance. Was: two different distances: the older 2019 figure in the hero, 27,000 ly in the opening paragraph. Now: about 27,000 ly everywhere (GRAVITY 2022, A&A 657 L12). Galactic Center

  • Corrected · Galactic Center mass. Was: 4.15 million suns (2019 value). Now: about 4.3 million suns (GRAVITY 2022, A&A 657 L12), paired with the 27,000 ly distance. Galactic Center

  • Corrected · S2 speed. Was: 7,700 km/s is 2.5% of c. Now: 2.6% of c. Galactic Center

  • Corrected · Tracking time. Was: more than two decades. Now: more than three decades (data from 1992). Galactic Center

  • Corrected · Event horizon. Was: ~12 million km, unlabelled. Now: labelled Modeled, assuming a non-spinning black hole. Galactic Center

  • Corrected · S2 orbit. Was: far point 1,880 AU. Now: about 1,930 AU. Galactic Center

  • Corrected · Cards 02 and 03 sources. Was: generic “GRAVITY Collaboration”. Now: GRAVITY 2018 (A&A 615 L15), 2020 (A&A 636 L5), Yusef-Zadeh 2025 (ApJL 980 L35), EHT 2022 (ApJL 930 L12). Galactic Center

  • Corrected · Mission wording. Wording corrected to match sources: MOXIE, the 2018 storm, blue sunsets. MOXIE: was “breathable”, now “made oxygen” (Hoffman 2022). 2018 dust storm: was “blacked out”, now “darkened” (Guzewich 2019). Blue sunsets: narrowed to blue light near the Sun at sunset (NASA PIA19401). No numbers changed. Mission

  • Corrected · Article 03 S2 speed. Was: “7,650 km/s, roughly 2.5% of the speed of light”; on 2026-10-14 it was changed to “7,650 km/s, roughly 2.55% of the speed of light” without a log entry. Now: 7,700 km/s, about 2.6% of the speed of light (GRAVITY 2020, A&A 636, L5), so the whole site uses one figure. Article 03

  • Corrected · Mission radiation. Was: “Curiosity measured roughly 0.6 millisieverts of radiation a day on the ground”. Now: “about 0.64 mSv/day from cosmic rays (Curiosity, Gale crater)”, cited to Hassler et al. 2014, Science. Mission

  • · 002 Power. Was: 40 kWe crew load; fission 4 × 10 kWe at about 7 t against about 9.8 t of solar + batteries. Now: 78.8 kW total load (crew 31.1, O₂ plant 34, propellant cooling 6.7, breathing O₂ up to 7); 10 + 1 spare 10 kWe units, about 87.5 kWe delivered, Modeled 16.5–19.8 t; 5 + 1 units for the first expedition if the O₂ plant runs before the crew lands. Why: the load left out the oxygen plant, propellant cooling and breathing oxygen, and we mixed up NASA’s figures: 92 kWe is the solar-option load and about 30 kWe the nuclear one (Cataldo 2009, DRA 5.0); Rucker 2016 gives 17.8 t solar against 9.15 t fission for a 120-day dust storm at full power. Study 002

  • · 001 Life support. Was: imports 9.3 → 3.5 t/yr. Now: Modeled 11.3 → 3.6 t/yr. Why: we used NASA’s in-transit oxygen and water rates instead of the Mars-surface rates (BVAD 2022). Study 001

  • · 003 Radiation. Was: 2 m, 480 t of cover. Now: about 3.8 m, Modeled ~920 t. Why: we misread the source’s solar-activity case (Röstel 2020) and credited one paper to the wrong authors (Zhang 2022). Study 003

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