UK White Paper on Space-based total solar eclipse observations: structure and dynamics of the solar atmosphere

Amir Caspi; Anthony R. Yeates; Daniel B. Seaton; David Orozco Suarez; Eleanna Asvestari; Erika Palmerio; Francisco Javier Bailen; Giulio del Zanna; Greta Cappello; Huw Morgan

arxiv: 2606.05244 · v1 · pith:7Y4JUKU2 · submitted 2026-06-03 · astro-ph.IM · astro-ph.SR

UK White Paper on Space-based total solar eclipse observations: structure and dynamics of the solar atmosphere

Lucie M. Green , Nicola Baresi , Huw Morgan , Matt Gunn , Amir Caspi , Daniel B. Seaton , Giulio Del Zanna , Yeimy J. Rivera

show 14 more authors

Francisco Javier Bailen David Orozco Suarez Anthony R. Yeates Peter Wyper Nawin Ngampoopun Nathalia Alzate Simone Di Matteo Erika Palmerio Richard J. Morton Eleanna Asvestari Manuela Temmer Greta Cappello Teodora Mihailescu Karl Battams

This is my paper

Reviewed by Pith T0 review T1 audit T2 compute T3 formal T4 kernel 2026-06-28 04:21 UTCgrok-4.3pith:7Y4JUKU2 record.json open to challenge →

classification astro-ph.IM astro-ph.SR

keywords solar eclipse observationssolar coronasolar magnetic variabilityspace-based occultationMESOMsolar atmosphere dynamicsSTFC solar roadmap

0 comments

The pith

A proposed spacecraft mission would use the Moon as an occulting disk to observe the solar atmosphere during total eclipses from space.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper proposes the Moon-Enabled Sun Occultation Mission (MESOM) as a way to conduct space-based total solar eclipse observations. This approach would provide data on the structures, dynamics, and energetics of the solar corona and atmosphere. The observations target open questions about solar magnetic variability, the solar cycle, and Sun-planet connections as outlined in the STFC Solar System Advisory Panel roadmap. The mission is presented as also advancing several pillars of the UK National Space Strategy.

Core claim

The Moon-Enabled Sun Occultation Mission (MESOM) directly addresses key open questions on the causes and consequences of solar magnetic variability, the structures and energetics of the Sun, and Sun-planet connections, while delivering several Pillars of the National Space Strategy.

What carries the argument

Moon-Enabled Sun Occultation Mission (MESOM), a spacecraft concept that uses the Moon for solar occultation to enable total eclipse observations from space.

If this is right

Improved constraints on how magnetic fields confine plasma and drive heating, flows, and energisation in the solar atmosphere.
Better characterisation of the build-up and release of energy in solar eruptions.
Direct contributions to understanding the impact of solar processes on planetary environments.
Alignment with multiple UK National Space Strategy pillars through the same observations.
Support for STFC roadmap goals on solar variability predictability and fundamental Solar System processes.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

If the orbital geometry works, repeated eclipse observations could be scheduled more frequently than ground-based events allow.
The approach might reduce the need for artificial coronagraphs on future missions by leveraging a natural occulter.
Data from such observations could feed into models that link solar magnetic evolution directly to space weather impacts on Earth.

Load-bearing premise

The assumption that a spacecraft-based mission using the Moon for solar occultation is technically feasible, cost-effective, and would deliver scientifically superior data on solar atmosphere dynamics compared with existing or alternative planned missions.

What would settle it

A technical feasibility assessment or end-to-end simulation demonstrating that required spacecraft trajectories, pointing stability, and data quality cannot be achieved or would not exceed performance of current or planned solar observatories.

read the original abstract

Our Sun is uniquely placed to enable a detailed study of astrophysical plasmas and how they are governed by the magnetic fields that thread through them. On the one hand, magnetic fields confine plasma and determine plasma heating, flows, and energisation. On the other hand, magnetic fields and their evolution give rise to the most violent eruptions in the Solar System. Understanding the details of how energy is built up and released, and the impact of these physical processes on the plasma, remain key open questions that directly map to UKRI's science strategy through the STFC Solar System Advisory Panel's roadmap for Solar System research goals: What are the causes, consequences and predictability of solar magnetic variability and the solar cycle? What are the structures, dynamics and energetics of the Sun? What are the underlying processes that drive Sun-planet connections? And what are the fundamental processes at work in the Solar System? As laid out in this White Paper, the Moon-Enabled Sun Occultation Mission (MESOM) directly addresses these questions and in doing so delivers several Pillars of the National Space Strategy.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Desk Editor's Note private letter to a colleague

This is a UK-focused white paper advocating the MESOM lunar-occultation mission concept, but the science-case mapping stays at the level of assertion without technical or comparative detail.

read the letter

The core of the paper is a proposal for the Moon-Enabled Sun Occultation Mission to observe the solar atmosphere during eclipses from space. It ties the idea to four STFC roadmap questions on magnetic variability, solar structures, Sun-planet links, and fundamental processes, plus the National Space Strategy pillars. That alignment is the main new element; the specific MESOM framing appears to be an incremental mission-design suggestion rather than a first-principles advance.

What the document does cleanly is lay out how a space-based eclipse platform could in principle supply continuous high-resolution views of the corona and inner heliosphere without the usual stray-light or duty-cycle limits of ground-based eclipses. The authors correctly note that existing assets like SOHO/LASCO and STEREO already provide some of this coverage, so the case rests on claimed improvements in resolution or continuity.

The soft spot is that the paper supplies almost no supporting numbers or diagrams. There is no orbit sketch, no occultation geometry calculation, no instrument requirements, no signal-to-noise estimate, and no side-by-side comparison against current or planned missions. The repeated claim that MESOM “directly addresses” the roadmap questions therefore remains an assertion rather than a demonstrated link. Without those elements the feasibility and superiority arguments cannot be evaluated.

This piece is aimed at UK solar-physics groups and funding panels who already follow the STFC roadmap. A reader already convinced of the science questions will find a concise advocacy summary; anyone needing quantitative mission trade-offs will not. It is coherent on its own terms as a strategy document and shows honest engagement with the cited roadmaps, so it deserves a serious referee rather than desk rejection if the target venue accepts white papers.

Referee Report

2 major / 1 minor

Summary. The manuscript is a UK White Paper advocating for the Moon-Enabled Sun Occultation Mission (MESOM) to enable space-based total solar eclipse observations using the Moon. It claims that MESOM directly addresses four STFC Solar System Advisory Panel roadmap questions on the causes/consequences of solar magnetic variability, structures/dynamics/energetics of the Sun, Sun-planet connections, and fundamental solar system processes, while also advancing pillars of the National Space Strategy.

Significance. If the mission were shown to be technically feasible and to deliver data superior to existing assets for solar atmosphere studies, it could contribute to understanding solar magnetic activity and space weather. As presented, however, the paper offers no new evidence, derivations, or comparisons and functions primarily as an advocacy document aligned with prior UKRI roadmaps rather than an original scientific or technical contribution.

major comments (2)

[Abstract] Abstract: the claim that MESOM 'directly addresses' the four STFC roadmap questions supplies no technical description of occultation geometry, orbit design, instrument requirements, data products, or quantitative comparison against SOHO/LASCO, STEREO, or planned missions, so the asserted mapping remains unsupported.
[Main text] Main text: the assumption that a lunar-occultation spacecraft would be technically feasible, cost-effective, and scientifically superior for solar atmosphere dynamics is stated without supporting analysis of feasibility, cost, or performance metrics relative to current or alternative missions.

minor comments (1)

The manuscript would benefit from explicit section headings that separate advocacy statements from any technical content.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for their review. This document is a strategic White Paper whose purpose is to advocate for the MESOM concept and its alignment with UK research priorities rather than to deliver a technical mission study. We address the major comments below.

read point-by-point responses

Referee: [Abstract] Abstract: the claim that MESOM 'directly addresses' the four STFC roadmap questions supplies no technical description of occultation geometry, orbit design, instrument requirements, data products, or quantitative comparison against SOHO/LASCO, STEREO, or planned missions, so the asserted mapping remains unsupported.

Authors: The abstract statement reflects the conceptual alignment of lunar-occultation eclipse observations with the four STFC roadmap questions as elaborated in the main text. We accept that the abstract itself provides no supporting technical details. We will revise the abstract to read that MESOM 'is designed to address' these questions through its unique observational capabilities, and we will add a clarifying sentence that the document is a high-level advocacy paper rather than a technical proposal. revision: yes
Referee: [Main text] Main text: the assumption that a lunar-occultation spacecraft would be technically feasible, cost-effective, and scientifically superior for solar atmosphere dynamics is stated without supporting analysis of feasibility, cost, or performance metrics relative to current or alternative missions.

Authors: As a White Paper the manuscript intentionally limits itself to scientific motivation and strategic alignment; detailed engineering feasibility, cost modelling and quantitative performance comparisons lie outside its scope and would be addressed in subsequent mission-definition studies. We will add a short paragraph in the main text noting that full technical and cost assessments remain to be performed and that the claimed advantages are based on the geometric benefits of lunar occultation for extended-duration corona observations. revision: yes

Circularity Check

0 steps flagged

No circularity: white paper asserts mission relevance without derivations or self-referential reductions

full rationale

The document is a mission advocacy white paper. Its central claim is that the proposed MESOM concept 'directly addresses' four STFC roadmap questions on solar variability, structures, energetics, and Sun-planet connections. This mapping is presented as an assertion of scientific alignment rather than a derivation from equations, fitted parameters, or prior self-citations. No load-bearing steps reduce by construction to inputs; there are no predictions, ansatzes, uniqueness theorems, or renamings of known results. External strategy documents are referenced but do not create internal circular logic. The paper is self-contained as a proposal document.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

No free parameters, axioms, or invented entities are introduced; the document contains no scientific modeling or derivations.

pith-pipeline@v0.9.1-grok · 5824 in / 1096 out tokens · 34322 ms · 2026-06-28T04:21:08.836533+00:00 · methodology

discussion (0)

Reference graph

Works this paper leans on

3 extracted references · 1 canonical work pages · 1 internal anchor

[1]

Scientific questions and general observation strategy MESOM aims to address several high-priority science questions related to the solar atmosphere and its links to the solar wind. To achieve this, it is necessary to make quantitative determinations of the properties of both the plasma and magnetic field spanning 2 the chromosphere, to the corona and into...

2023
[2]

MESOM will recreate total solar eclipse conditions in space by using the Moon as a natural occulter once every synodic month (~29.6)

Enabling mission: MESOM MESOM (Moon Enabled Sun Occultation Mission) will view the atmosphere of the Sun from the upper chromosphere to the corona with total solar eclipse conditions, and higher altitudes of the solar atmosphere/solar wind acceleration region outside times of totality. MESOM will recreate total solar eclipse conditions in space by using t...

2017
[3]

Global and strategic context MESOM builds on a decades-long development of UK ground-based eclipse instrumentation and expertise, and decades of experience of space instrumentation, orbit design and small satellite development. MESOM’s ability to observe the full height range in the solar atmosphere will enable energy flow/transport throughout the atmosph...

work page internal anchor Pith review arXiv 2024

[1] [1]

Scientific questions and general observation strategy MESOM aims to address several high-priority science questions related to the solar atmosphere and its links to the solar wind. To achieve this, it is necessary to make quantitative determinations of the properties of both the plasma and magnetic field spanning 2 the chromosphere, to the corona and into...

2023

[2] [2]

MESOM will recreate total solar eclipse conditions in space by using the Moon as a natural occulter once every synodic month (~29.6)

Enabling mission: MESOM MESOM (Moon Enabled Sun Occultation Mission) will view the atmosphere of the Sun from the upper chromosphere to the corona with total solar eclipse conditions, and higher altitudes of the solar atmosphere/solar wind acceleration region outside times of totality. MESOM will recreate total solar eclipse conditions in space by using t...

2017

[3] [3]

Global and strategic context MESOM builds on a decades-long development of UK ground-based eclipse instrumentation and expertise, and decades of experience of space instrumentation, orbit design and small satellite development. MESOM’s ability to observe the full height range in the solar atmosphere will enable energy flow/transport throughout the atmosph...

work page internal anchor Pith review arXiv 2024