The Eight-Planet Photograph

At p. 162 the book stops arguing and asks: “If we fully simulated the Solar System on a computer for Feb 22, 2025, would we be able to reproduce the eight-planet photo using the same coordinates? … the position and orientation would need to match, given the camera’s coordinates. How closely would the simulation match reality?” The caption at p. 163 puts it in one line: “Will heliocentric simulations match the planet placement in this photo?” It names a date and a criterion. So we ran it.

What the claim is

The chapter is Unknown Luminaries; its thesis at p. 161 is that “we have no idea what these luminaries in the sky really are or how they work,” and the simulation challenge is offered as a test of it. This page answers the challenge as the book states it, for the seven planets at p. 163 (Earth is the eighth).

What the photograph is

The book has both replies to a bare yes ready: at pp. 155–157 planetary imaging is a processing pipeline (“How to manipulate a photo to achieve the desired planet 101” — answered on Stacked, Sharpened — and Beside the Point), so you matched a composite; and at p. 164 “a brief introduction to geocentrism is highly recommended before continued reading,” so a geocentric model gives the same sky.

The QR at p. 163 resolves to a Live Science report on an image by the astrophotographer Josh Dury, taken from the Mendip Hills in Somerset just after sundown on 22 February 2025. Dury describes his method: a panorama of several panes, each captured in multiple exposures, with astronomy software used to locate the fainter planets. It is the only way the picture could exist, but it means the photograph cannot check an ephemeris — a table of computed positions — because an ephemeris is part of how it was made. Comparing the simulation to this image tests the stitching, not the sky. That is the book’s point.

Why it had to be built that way

Computed for the Mendip Hills at 17:50 UT, twelve minutes after sunset (altitude is height above the horizon, azimuth the compass bearing; magnitude is the astronomers’ brightness scale, larger meaning fainter):

The Sun set at 17:38 UT and Mercury followed it at 18:37: all seven stood above that horizon for fifty-nine minutes, through civil and nautical twilight, with the two faintest never visible to an unaided eye. No single exposure could hold Venus and Neptune together, and none could find Neptune without being told where to point.

So: does it match?

Yes. Positions from JPL’s DE440 ephemeris — the planetary position table fitted to radar ranging, spacecraft tracking and centuries of optical observation — taken as apparent geocentric (corrected for light-time and aberration: where the planets are seen) reproduce the arrangement. Outward from the sunset point:

All seven fall within 5.6° of the ecliptic — the Sun’s path, so the reference needs no fitting; Venus, at +5.6°, is the extreme. The order — Mercury, Saturn, Neptune, Venus, Uranus, Jupiter, Mars — is nothing like their order by distance, and that scrambling is what the model predicts: a photograph records the arrangement in longitude from inside the system, not a cross-section of it. It is also the order in the picture. The Live Science text lists the planets in prose, not along the line; Dury’s own annotated version of the frame, published by Space.com, labels them descending toward the sunset glow as Mars, Jupiter, Uranus, Venus, then Neptune above Saturn and Mercury at the horizon — Neptune between Venus and Saturn, where the ephemeris puts it.

The camera’s coordinates matter for half of his question: where the line sits against the horizon, and its tilt, depend on latitude, longitude and clock. The separations between the planets do not: recomputed from London, Cape Town, Sydney and Quito, no pair separation moves by more than 46 arcseconds (an arcsecond is 1/3600 of a degree; the 46 is London against Sydney, nearly antipodal, and Venus at 0.38 AU is the planet that moves). Parallax — the shift in apparent position between two viewpoints — is the only term that cares where you stand, and at these distances it is negligible.

The check anybody can run

Two instants appear on this page: 17:50 UT, twelve minutes after sunset, is the window the composite’s panes were taken in, and 18:39:23 UT is simply where the planetarium’s clock stood for the check that follows — Jupiter at 58.9° in the first and 60.5° in the second is the same planet fifty minutes on. A planetarium program set to Priddy, Somerset, at 18:39:23 UT that evening agrees with our computation for the same instant at every point (both are in the method notes) — though its positions descend from the same ephemeris lineage as ours, so this tests our arithmetic, not the ephemeris. Two details do more work than the agreement: 18:39 is two minutes after Mercury set (computed altitude −1.0°, drawn on the horizon where a refracted setting object sits), so a look a quarter of an hour later finds six planets, not seven; and Uranus and Neptune, on the line at +53.9° and +10.5° but unlabelled at default settings, are objects a planetarium declines to draw for a person standing there — the fact that made the composite necessary.

What the match settles, and what it does not

Less than it looks, and the book is right about that. A photograph records directions, which more than one arrangement can share. Matching this frame does not establish where anything is — only that where everything would appear was known in advance. It does not put the Sun at the centre: hold the Earth still, let the Sun carry the planetary orbits round it, and every direction in the photograph is unchanged, so the pointer at p. 164 goes unanswered here. Anyone offering the picture as proof of a heliocentric solar system is overclaiming, and the book is entitled to say so. And it says nothing about what the planets are made of: of the two halves of the p. 161 thesis, “what these luminaries really are” is left where the book found it.

“How they work” is not. A model with far more observational constraints than free parameters, tabulating positions years ahead to a fraction of a planet’s apparent width, is not a description of something whose behaviour is unknown. That — behaviour, nothing about nature — is all the match settles, and all the verdict above rests on.

The geocentric pointer would still have to carry two things this photograph does not test: the phases of Venus — gibbous (more than half lit) when small and distant, a thin crescent when large and near — which the classical arrangement keeping Venus always between Earth and Sun cannot produce; and the retrograde loops of Mars around opposition (when it stands opposite the Sun), which a heliocentric model gives with no adjustment (rates on The Sky Turns at One Rate). The geocentrism that survives both has the planets orbiting the Sun and only the Sun orbiting the Earth: the same orbits, the same predictability.

So the fair statement is two-sided. The photograph cannot prove a heliocentric solar system, and it is entirely consistent with one: every direction in it is what that model said it would be, decades ahead. The two things that would decide the pointer are not open questions. The phases of Venus were settled in the winter of 1610, when Galileo watched the planet run from a small gibbous disc to a large thin crescent — a cycle the classical arrangement, with Venus always between Earth and Sun, cannot produce — and anyone with a small telescope and a season of evenings can watch it again. The retrograde rates of Mars and the outer planets are computed from orbital speeds and distances and cross-checked against the almanac on The Sky Turns at One Rate. The chapter stops at the question. Had it asked a specific one, the answer was already there.

The version of his test that does decide

One hedge first, because it is the honest one: what follows decides the shape of the ground, not what orbits what. A geocentric globe passes it exactly as a heliocentric one does, since the arrangement is fixed everywhere on Earth and every difference between two observers is orientation — which is exactly where a flat plane and a globe part company. Two frames, same instant, 22 February 2025 at 18:45 UT:

Largest disagreement between the two sites in any pair separation: 21 arcseconds. Identical arrangement; 149° apart in azimuth.

The usual reply is that a dome, or refraction in it, bends the directions. Not this one: refraction lifts an object in altitude and leaves azimuth alone, and no bending that kept every pair separation within 21 arcseconds could carry the pair 149° round the compass. Perspective is no better: a light above a flat plane leans toward the point beneath it as an observer walks away — convergence, the flat-plane prediction, and the opposite of what the two sites see.

The number the flat plane owes is this. Its two observers stand on one surface and share one “up”; all that differs between them is the direction to the centre of the map, and for London and Cape Town, 9,800 km apart on that map, those directions differ by 18.6°. A light far enough away for the pair separations to agree from both cities to 21 arcseconds — beyond about 0.4 AU, by Venus’s own parallax — is then seen from both in the same direction in space: the same altitude to a hundredth of a degree, and bearings 18.6° apart. Bring the lights close enough to be seen at different altitudes, say 5,000 km up, and the pair separations differ between the cities by tens of degrees, not 21 arcseconds. The globe’s 30° of altitude and 149° of bearing are two frames rotating with the ground beneath them. And the bearings need no phone compass, which a reader may say was calibrated to a globe: the sunset point that evening, or a landmark on a map, gives azimuth with nothing to argue about.

Where this page could be wrong, and what would change our mind

• The two-hemisphere test is proposed, not performed. A matched pair, same instant, with Jupiter in the same compass direction from both sites would be a real result, and we would publish it.
• The composite’s pane timestamps are not in hand, nor a copy of the frame at a measurable scale, so the “all seven at once” window is checked against the ephemeris, not the exposures. Panes timestamped outside 17:38–18:37 UT would break that framing — a criticism of the photograph open to the book.
• DE440 is a fit, not a revelation. The claim is that it predicts events it was never shown, not that it was derived from first principles. Recomputing this date on an ephemeris fitted long before 2025 should leave the arrangement unchanged. On DE421, fitted in 2008, all seven separations agree with DE440’s to a tenth of an arcsecond; DE200 (1981) and DE405 (1997) would be the fuller version of the check, and if either failed the framing above would weaken.
• A luminary breaking the elongation rule. Elongation is a planet’s angular distance from the Sun; Mercury and Venus never exceed about 28° and 47°, Mars and Saturn reach 180°, at opposition. One documented sighting of Venus at opposition and the structure behind all of this is gone.

Sources & further reading

• Levi Miller, Globe Deconstruction? (prerelease) — pp. 162–163 (the question and the QR), p. 161 (the chapter thesis), pp. 155–157 (the imaging-process argument), p. 164 (the geocentrism pointer).
• Galileo Galilei, letter to Giuliano de’ Medici, 11 December 1610 (the “Cynthiae figuras” anagram, resolved 1 January 1611), announcing the phases of Venus; discussed in Drake, S., Galileo at Work (1978).
• Space.com, “Astrophotographer captures ‘rare’ planetary parade as 7 planets align in the night sky,” February 2025 — carries Dury’s annotated frame with the seven labels. space.com
• Live Science, “‘Planet parade’ photo captures 7 planets in a line over Earth — possibly for the 1st time ever,” February 2025 — the p. 163 QR target, with Josh Dury’s account of the composite. livescience.com/space/astronomy/planet-parade-photo-captures-7-planets-in-a-line-over-earth-possibly-for-the-1st-time-ever
• Stellarium Web (stellarium-web.org); JPL DE440 (Park et al., 2021) via Skyfield.
• Newhall, X X, Standish, E. M. and Williams, J. G., “DE 102: a numerically integrated ephemeris of the Moon and planets spanning forty-four centuries,” Astronomy & Astrophysics 125, 150 (1983) — planetary positions through the year 3002, tabulated forty-two years before the photograph.
• On this site: Jupiter’s Shadows (the other specific argument in this chapter), The Sky Turns at One Rate, Self-Test Protocol (Test 12).