diff --git a/src/app/features/body-detail/body-view-model.spec.ts b/src/app/features/body-detail/body-view-model.spec.ts
index 797df68..5a22777 100644
--- a/src/app/features/body-detail/body-view-model.spec.ts
+++ b/src/app/features/body-detail/body-view-model.spec.ts
@@ -3,7 +3,7 @@ import { describe, expect, it } from 'vitest';
 import { BodyRecord, OrbitalElements } from '../../shared/models/body.model';
 import { ExoplanetRecord } from '../../shared/models/exoplanet.model';
 import { StarRecord, SUN_STAR_ID } from '../../shared/models/star.model';
-import { buildBodyViewModel, heliocentricPeriodDays, luminosityOf, starSurfaceOf } from './body-view-model';
+import { buildBodyViewModel, heliocentricPeriodDays, luminosityOf, publishedTemperaturesK, starSurfaceOf } from './body-view-model';
 
 const orbit = (overrides: Partial<OrbitalElements> = {}): OrbitalElements => ({
   semiMajorAxisAu: 1,
@@ -163,6 +163,19 @@ describe('starSurfaceOf', () => {
     expect(buildBodyViewModel('proxima-cen-d', catalogues)?.appearance.equilibriumTemperatureK).toBeCloseTo(296, 0);
   });
 
+  it("gives the star field the temperature the disc is drawn at, where a host's planets give it different ones", () => {
+    // 193 hosts do: host 1070876212's three rows give 4 094, 4 094 and 3 640 K. The field is tinted
+    // from one map of every host and the disc from the host's own planets, so both must take the same row.
+    const rows = [
+      { ...proximaB, id: 'd', hostStarTemperatureK: undefined },
+      { ...proximaB, id: 'b', hostStarTemperatureK: 4094 },
+      { ...proximaB, id: 'c', hostStarTemperatureK: 3640 },
+    ];
+    const other = { ...proximaB, id: 'other', hostStarId: 1, hostStarTemperatureK: 5000 };
+    expect(starSurfaceOf(proxima, rows).temperatureK).toBe(4094);
+    expect(publishedTemperaturesK([...rows, other]).get(proxima.id)).toBe(starSurfaceOf(proxima, rows).temperatureK);
+  });
+
   it('derives both otherwise, and says the radius is derived', () => {
     const surface = starSurfaceOf(proxima, [proximaB]);
     expect(surface.radiusDerived).toBe(true);
diff --git a/src/app/shared/astro/stellar.spec.ts b/src/app/shared/astro/stellar.spec.ts
index 09e24e5..b2bbf89 100644
--- a/src/app/shared/astro/stellar.spec.ts
+++ b/src/app/shared/astro/stellar.spec.ts
@@ -11,6 +11,7 @@ import {
   SOLAR_BOLOMETRIC_MAGNITUDE,
   SOLAR_EFFECTIVE_TEMPERATURE_K
 } from './stellar';
+import { dwarfSequenceAtType } from './spectral';
 
 /** Real catalogue rows, with the published luminosity each one should reproduce. */
 const SIRIUS = { magnitude: -1.44, distancePc: 2.6371, spectralType: 'A0m...', publishedLuminosity: 25.4 };
@@ -214,6 +215,15 @@ describe('a dwarf with a type and no colour', () => {
     expect(radius / 0.114).toBeGreaterThan(1 / 1.2);
     expect(radius / 0.114).toBeLessThan(1.2);
   });
+
+  it("carries a G magnitude to V at its type's G−V", () => {
+    // The same star measured in G, which for an M8 dwarf reads 3.11 magnitudes brighter than V: taken
+    // as V, it came out 17 times as luminous. One published star takes this path, Oph 11 (M9, G 18.91).
+    const inV = { magnitude: 19.57, distancePc: 14.35, spectralType: 'M8', magnitudeBand: 'V', colorIndex: null } as const;
+    const inG = { ...inV, magnitude: 19.57 + dwarfSequenceAtType('M8')!.gMinusV!, magnitudeBand: 'G' } as const;
+    expect(dwarfSequenceAtType('M8')!.gMinusV).toBeLessThan(-3);
+    expect(luminositySolar(inG)!).toBeCloseTo(luminositySolar(inV)!, 12);
+  });
 });
 
 describe('radiusFromLuminositySolar', () => {
diff --git a/src/app/shared/models/star-catalog.spec.ts b/src/app/shared/models/star-catalog.spec.ts
index a788dc0..2d85b37 100644
--- a/src/app/shared/models/star-catalog.spec.ts
+++ b/src/app/shared/models/star-catalog.spec.ts
@@ -103,7 +103,7 @@ describe('the photometry and distance error columns', () => {
     { id: 1, name: 'Sirius', x: 1, y: 0, z: 0, magnitude: -1.44, magnitudeBand: 'V', spectralType: 'A0m', colorIndex: 0.009, colorSystem: 'B-V', distanceError: 0.0036, source: 'hyg' },
     { id: 2, name: 'Gaia DR3 2', x: 0, y: 117, z: 0, magnitude: 11.2, magnitudeBand: 'G', spectralType: 'Unknown', colorIndex: 1.43, colorSystem: 'BP-RP', distanceError: 0.199, distanceFromGaia: true, source: 'gaia' },
     // A HYG star at Gaia's distance, and one no survey gave a magnitude, a colour or an error.
-    { id: 3, name: 'HD 3', x: 0, y: 0, z: 300, magnitude: 7, magnitudeBand: 'V', spectralType: 'K0', colorIndex: 1.0, colorSystem: 'B-V', distanceError: 0.000001, distanceFromGaia: true, source: 'hyg' },
+    { id: 3, name: 'HD 3', x: 0, y: 0, z: 300, magnitude: 7, magnitudeBand: 'V', spectralType: 'K0', colorIndex: 1.0, colorSystem: 'B-V', distanceError: 1e-12, distanceFromGaia: true, source: 'hyg' },
     { id: 4, name: 'Gaia DR3 4', x: 5, y: 5, z: 0, magnitude: 12, spectralType: 'Unknown', colorIndex: null, distanceFromGaia: true, source: 'gaia' },
     // A Hipparcos parallax smaller than its own error.
     { id: 5, name: 'HIP 5', x: 0, y: 200, z: 0, magnitude: 6, magnitudeBand: 'V', spectralType: 'B8', colorIndex: -0.1, colorSystem: 'B-V', distanceError: 1.4, source: 'hyg' },
@@ -124,7 +124,8 @@ describe('the photometry and distance error columns', () => {
     // A step is 0.05 % of distance at Sirius's 0.36 %, and 0.35 % at the 20 % Gaia's cut allows.
     expect(Math.abs(decoded[0].distanceError! - 0.0036)).toBeLessThan(0.0003);
     expect(Math.abs(decoded[1].distanceError! - 0.199)).toBeLessThan(0.002);
-    // Too small to round to a step, but published, so not read back as unpublished.
+    // Too small to round to a step — √(10⁻¹²) is 0.07 of one in 65 535 — but published, so not read
+    // back as unpublished. 10⁻⁶ was, at 255 steps; at 65 535 it rounds to 66 and never needed the floor.
     expect(decoded[2].distanceError).toBeGreaterThan(0);
     expect(decoded[3].distanceError).toBeUndefined();
     // Past the parallax itself there is no upper bound on the distance, which is what 100 % says.