Has Kronos devoured Planet Nine and its epigones?

Lorenzo Iorio

REVIEW 4 major objections 5 minor 6 references

Has Kronos devoured Planet Nine and its epigones?

T0 review · 4 major / 5 minor · reviewed 2026-08-03 · deepseek-v4-flash

Challenge this review Re-run · record.json Download PDF Read on arXiv ↗

Pith's one-line read Using Saturn's orbital precessions, the paper finds that Planet Nine, if it exists, must be near aphelion at 520 au or farther, while Planet X is ruled out and Planet Y shrinks to a distant Mercury-mass body.

desk verdict A careful, self-caveated application of standard quadrupolar perturbation theory to Planet Nine, X, and Y—but the 10× error inflation is the load-bearing step, and it is not derived from a covariance analysis. read the letter →

arxiv 2602.00802 v1 pith:XUYNCUJ6 submitted 2026-01-31 astro-ph.EP gr-qcphysics.space-ph

Lorenzo Iorio This is my paper

classification astro-ph.EPgr-qcphysics.space-ph

keywords PlanetNineSaturnorbitalprecessionPlanetaryephemeridesKuiperbeltXYCassiniSolarsystemperturbers

verification ladder T0 review T1 audit T2 compute T3 formal

The pith

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

The reading

The paper tries to show that the current best bounds on Saturn's orbital precession, taken as upper limits, severely squeeze the parameter space for three hypothetical outer-solar-system planets: Planet Nine, Planet X, and Planet Y. It argues that Planet Nine, if real, can only live near aphelion at a heliocentric distance of at least about 560–700 au, that the Planet X scenario is completely ruled out, and that Planet Y can only survive as a Mercury-sized object no closer than about 125 au. These are presented as hints rather than hard constraints, because the bounds come from ephemerides built without modeling any extra planet. The paper matters because it narrows where astronomers should actually look for these bodies and shows that a modest improvement in Uranus's orbit knowledge would settle the question almost entirely.

What carries the argument

The argument runs on the standard quadrupolar secular perturbation equations for a planet's Keplerian elements under the tidal field of a distant point mass — explicit formulas for the averaged rates of change of eccentricity, inclination, node, perihelion, and mean anomaly (Equations 1–7) — combined with the inequality |Δκ̇| ≤ σ_κ̇ (Equation 18), which treats Saturn's formal precession uncertainties as upper bounds on any unmodeled signal. The rates are functions of the perturber's mass, distance, and its angles (true anomaly, node, argument of perihelion), so imposing the inequality simultaneously on four Kronian elements carves out allowed regions in the perturber's parameter space. A ten

What would settle it

A dedicated planetary-ephemeris reduction that explicitly solves for Planet Nine, Planet X, and Planet Y in the force model — using the same Cassini and astrometric data — would either confirm the allowed regions or place the planet elsewhere. In particular, if a full fit finds a best-fit Planet Nine with a semimajor axis well below 520 au or a true anomaly far from 140°–220°, the central claim would be contradicted.

Watch

Extended reading notes

Core claim

The central claim is that Saturn's measured orbital precession rates, with their formal uncertainties rescaled by a conservative factor of ten, leave only narrow allowed regions for the proposed distant planets. For Planet Nine of 4.9 Earth masses, allowed orbital configurations exist only for a semimajor axis of 520 au, with the true anomaly confined between roughly 140° and 220°, placing the planet near aphelion; the heavier 8.4-Earth-mass version is squeezed into even narrower, disjointed allowed regions with a true anomaly of about 160°–200°. Translating these into sky coordinates, a 4.9-Earth-mass Planet Nine cannot be closer than roughly 560–600 au, and an 8.4-Earth-mass one cannot be

Load-bearing premise

The whole result rests on trusting that Saturn's formal post-fit precession uncertainties, even after a factor-of-ten inflation, are upper bounds on the precession that an unmodeled distant planet would induce; if the real uncertainties are larger or the signal is fully absorbed into the ephemeris fit, the allowed regions shrink or vanish and the Planet X exclusion loses its basis.

Editorial extensions

If this is right

If correct, the most promising search region for Planet Nine becomes the aphelion sky at heliocentric distances of roughly 560–700 au and beyond, not the closer perihelion zone.
Planet X, as recently proposed, would be ruled out by Saturn's orbit alone, so any future evidence for it would require either different orbital parameters or a rejection of the Saturn-based bounds.
Planet Y, if it exists, must be a Mercury-mass body at no less than about 125 au; an Earth-mass Planet Y is excluded.
If Uranus's orbital precessions were ever measured as accurately as Saturn's, the same method would exclude all three candidates as currently proposed unless they lie beyond roughly 750–950 au.
A hypothetical deep-space probe on a Voyager-like trajectory would accumulate a range shift of tens of kilometers from Planet Nine over about four decades, which is a measurable scale in principle.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

The aphelion-confinement result, if upheld, shifts the practical observing strategy for Planet Nine surveys: deep, wide-field searches should prioritize the region near the antisolar-point sky where an object at 600–700 au would appear slow-moving and faint.
The same precession-bounds method could be applied to Jupiter once its orbit is improved by Juno-era data, providing an independent cross-check on the Saturn-only conclusions.
If Planet Nine is really confined to such large heliocentric distances, the Kuiper-belt clustering that motivated it becomes harder to explain dynamically, since the planet's influence weakens with distance and the allowed orbital orientation is tightly restricted.
A dedicated ephemeris reduction that explicitly fits for Planet Nine, Planet X, and Planet Y simultaneously would provide a direct test of whether the allowed regions persist or shift, since the analytical bounds here assume the signal is not absorbed in the fit.

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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Desk Editor's Note

read the letter

The thing to know about this paper: it applies Saturn's measured orbital precessions to the three current hidden-planet hypotheses, and it gets real, concrete results—Planet X is excluded, Planet Y is squeezed to a Mercury-mass object at ≥125 au, and Planet Nine survives only near aphelion at 560–800 au. The internal geometry checks out: I recomputed the a=520 au cases and the allowed f ranges correspond to heliocentric distances of 600–800 au, matching the stated floors. This is not a sloppy paper.

What's actually new is the application to Siraj et al.'s 2025 Planet X and Planet Y, which were proposed only last year. The P9 part largely recovers Fienga et al.'s 2020 INPOP19a distance floor of ~500 au, but the tighter aphelion localization is new. The author deserves credit for pointing out the central weakness himself: the ephemerides were built without modeling the perturber, so the signal could be absorbed into solve-for parameters, making the constraints too tight. He then rescales the formal errors by ten, which is the worst case Pitjeva & Pitjev flagged, not a safety margin beyond it.

That is the soft spot, and the stress-test note lands on it correctly. Equation (18) treats the formal post-fit uncertainties, after a flat 10× inflation, as upper bounds on an unmodeled planet's secular precession. But the 10× factor is a round-number response to a warning, not a derived quantity. If absorption is worse than assumed, or the true uncertainties are larger than 10×, the P9 allowed regions shrink or vanish and the PX exclusion loses its basis. There is also a timescale mixing: the analytic rates are averaged over a full Saturn revolution (~29 yr), while the adopted σ's come from a ~13-yr Cassini arc. A short-arc signal can be partly absorbed into initial conditions. These are not fatal flaws—the paper explicitly says the zones 'may not be viewed as actual constraints'—but they mean the headline claims are conditional on an untested calibration factor.

Minor issues: the abstract's 'ruled out' wording outruns the conclusions' own disclaimer, and one Voyager ranging accuracy claim rests on a forum post. Neither is load-bearing.

Who is this for? People working on outer solar system planet searches and ephemerides-based constraints. It is a useful, honest probe of what current Saturn precession limits can say, and it sharpens the case for a dedicated data reduction with the perturber explicitly modeled. The paper deserves a serious referee—the method is standard, the results are reproducible from the text, and the caveats are transparent. I would not cite it as a definitive exclusion, but I would cite it as a well-posed constraint that needs confirmation.

Recommendation: send it to peer review. It is not a desk reject. But the referee should demand a dedicated injection-recovery test or a covariance-based error estimate before the 'ruled out' language is taken at face value.

Referee Report

4 major / 5 minor

Summary. The paper uses analytic, quadrupolar secular perturbation theory (Eqs. 1–7) to compute the long-term rates of change of a planet's Keplerian elements induced by a distant point-mass perturber. These rates are compared, via Eq. (18), with formal uncertainties in Saturn's precession rates drawn from the author's earlier reduction of the EPM2017 ephemerides (Table 1), after inflating those uncertainties by a factor of ten. The authors then map the allowed regions of true anomaly, node, argument of perihelion, and sky position for Planet Nine, Planet X, and Planet Y, concluding that Planet Nine survives only near aphelion at a semimajor axis of 520 au, with heliocentric distances roughly 560–700 au depending on mass; that Planet X is completely ruled out; and that Planet Y is limited to Mercury-mass bodies at no less than about 125 au. A numerical simulation shows that a Voyager-1-like probe would experience a P9-induced range shift of 20–40 km over 39 years. The paper repeatedly cautions that the derived zones are not actual constraints because the ephemerides were produced without modeling any of these perturbers, and that signal absorption into solved-for parameters is possible.

Significance. The analytic formulas are standard but cleanly assembled, and the numerical implementation is transparent and internally consistent: a=520 au with e=0.538–0.259 gives perihelia of 240–385 au and aphelion distances of 655–800 au, matching the quoted floors. If the underlying uncertainty calibration could be trusted, the paper would provide observationally relevant guidance for the Planet Nine search, pointing to a narrow aphelion region at very large heliocentric distance, and would independently disfavor the proposed Planet X. The explicit acknowledgment of the absorption problem and the careful distinction between 'hints' and 'constraints' is commendable. However, the central load-bearing premise—that a flat 10× inflation of formal post-fit errors yields upper bounds on a separately unmodeled planet's secular signal—is asserted rather than demonstrated. The paper itself concedes in Sections 3 and 7 that the signal may be partially or totally absorbed and that the allowed zones 'may not be viewed as actual constraints.' Thus the significance is real but conditional: the paper is best read as a well-posed sensitivity study whose headline exclusions require additional calibration to

major comments (4)

[§3, Eq. (18); §4, Table 1] The entire exclusion/allowed-region analysis rests on treating σ_κ̇, after a flat factor-10 inflation, as upper bounds on the secular precession induced by an unmodeled planet. This factor is not derived from a covariance analysis or an injection-recovery test; it is a round-number response to Pitjeva & Pitjev's warning that true uncertainties may be up to ten times larger. At face-value formal errors, all candidates are excluded; at 10×, only narrow P9 aphelion islands survive and PX is 'completely ruled out.' A 10× inflation is therefore the optimistic edge of the plausible range, not a conservative safety margin. The paper should either provide a dedicated calibration (e.g., injecting a synthetic P9/PX/PY signal into a Cassini-like data reduction and measuring the recovered uncertainty) or explicitly downgrade the abstract's claims from constraints to sensitivity illustrations.
[§2 vs. §3; Eqs. (2)–(6)] The analytic rates are averaged over a full Saturn orbital revolution (about 29 yr), whereas the adopted σ's were derived from a ~13-year Cassini arc. Over a fraction of an orbit, a distant perturber's signature is largely degenerate with initial conditions and other solved-for parameters, so the inequality |Δκ̇| ≤ σ_κ̇ does not directly bound the full-orbit secular rate. This timescale mismatch is distinct from the general absorption concern and should be quantified or at least explicitly discussed in the derivation of Eq. (18). Without such a discussion, the claimed exclusion of Planet X is not supported by the data as used.
[§4, Planet X and Planet Y] The statement 'The PX scenario is completely ruled out' is stronger than the evidence permits. It depends entirely on the 10× inflation and on treating the four Kronian element uncertainties as four independent, hard bounds. No dedicated PX-modeled ephemeris is used, and the paper's own Section 7 concedes that the zones may not be actual constraints. Similarly, the conclusion that Planet Y can be a Mercury-sized object at a_Y ≥ 125 au is derived for a single assumed eccentricity e_Y=0.2, with no sensitivity scan in e_Y; a different eccentricity could move or eliminate the allowed regions. The abstract and Section 4 should be reworded to state that these are provisional consequences of the adopted uncertainty model.
[§4, simultaneous inequalities] Eq. (18) is applied simultaneously to e, I, Ω, and ϖ using their formal uncertainties as if they were independent. The errors in these precession rates are derived from the same covariance solution and are likely correlated; imposing four independent inequalities can produce allowed regions that are too large or too small compared with a proper joint chi-square threshold. A covariance-aware criterion, or at least a discussion of the effect of correlations, would strengthen the reliability of the plotted islands in Figures 1–4.

minor comments (5)

[Abstract and §7] The abstract states 'Planet X appears to be ruled out' and 'Planet Y can be just a Mercury-sized object,' while Section 7 explicitly says the allowed zones 'may not be viewed as actual constraints.' The wording should be harmonized so the provisional nature is visible in the abstract.
[Footnote 2] The Greek transcription of Kronos ('Κρ/οξιαονος, -ου, /δασιαο') appears garbled; please restore the correct characters or transliteration.
[References] Several author names contain corrupted characters, e.g., 'A. Pradeepku"Mar" Girija' and 'Ster"Nov"sky'; these are likely LaTeX/Unicode encoding artifacts and should be repaired.
[Throughout] The word 'Voyager' is repeatedly typeset as 'V oyager' (with a space), and 'lef column' appears in Figure 5; these should be corrected.
[§2, Eq. (8)] The heliocentric distance r' is written as an instantaneous function of the perturber's true anomaly f', while the preceding text assumes r' is constant over one Saturn revolution. The time-scale of the perturber's orbital motion relative to Saturn's period should be stated explicitly.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: P9/PX/PY constraints are forward exclusions from external Saturn precession uncertainties, not re-fits of the claimed results.

full rationale

The derivation chain is: (i) analytic quadrupolar rates for a distant perturber (Eqs. 1-7, from Hogg et al. 1991); (ii) observed Saturn precession uncertainties (Table 1, from Iorio 2019, itself computed from the external EPM2017 formal errors of Pitjeva & Pitjev 2018); (iii) inequality Eq. 18, that a real P9/PX/PY would not induce a secular Kronian precession larger than the adopted uncertainty; (iv) a grid search over the external candidate parameter ranges. The 'allowed regions' are exclusions obtained by evaluating this inequality, so the conclusions are not built into the inputs. The author's self-citations (Iorio 2017 for the method and Iorio 2019 for the sigma values) are not load-bearing in a circular sense: Iorio 2019 is a parameter-free propagation of externally published ephemeris errors, and the resulting P9 aphelion constraints are cross-checked against independent explicit-modeling reductions (Fienga et al. 2016, 2020; Holman & Payne 2016b). The paper also repeatedly disclaims the constraints, saying they 'may not be viewed as actual constraints' and are 'hints of what might be detectable', which further shows no overreach. The 10x inflation of formal uncertainties is a modeling/calibration limitation that affects robustness; it does not make any predicted quantity equal to an input by construction, so it is a correctness risk rather than a circularity.

Assumptions & free parameters 2 free parameters · 5 assumptions · 0 invented entities

No new entities are invented: P9, PX, and PY are hypotheses imported from the cited literature (Brown & Batygin 2021; Siraj et al. 2025a,b); the only introduced item is the proposed name 'Telisto' (Iorio 2017, 2025), a naming choice without a falsifiable handle of its own. The analysis is honest about its inputs: two hand-chosen numbers (the 10× error rescale and e_Y = 0.2) plus the cited candidate windows and the EPM2017-derived uncertainty table determine everything. No parameter is fitted to make the target result appear; the exclusions arise from inequality scans. The dominant fragility is not a hidden constant but the interpretive assumption that ephemeris residuals constrain an unmodeled planet at all.

free parameters (2)

Uncertainty rescaling factor = 10
The formal EPM2017 errors on Saturn's precessions are multiplied by 10 before the exclusion scan; the existence of the P9/PY allowed regions depends entirely on this hand-chosen factor, and Pitjeva & Pitjev (2018) warn the real errors may be up to 10× larger, so the rescale is a boundary, not a margin. Sections 3, 4.
Planet Y eccentricity e_Y = 0.2
Chosen 'realistically' in Section 4 as a moderate value: extreme eccentricity would produce an unobserved apsidal clustering signature, and a circular orbit is deemed unlikely by PY's proposed formation path. All PY allowed-region maps assume this single value.

assumptions (5)

standard math Quadrupolar secular perturbation theory: the long-term rates of change of a planet's Keplerian elements due to a distant pointlike perturber are given by Eqs. (1)–(7), averaged over one planetary revolution with the perturber held fixed (Hogg et al. 1991).
The engine of the whole analysis; valid for r' >> a and P' >> P, which holds for Saturn (a≈9.6 au, P≈29 yr) against perturbers at 100–800 au.
domain assumption Post-fit residuals imply physical upper bounds: |Δκ̇| ≤ σ_κ̇ (Eq. 18), with σ from EPM2017 fits that did not model any extra planet.
Section 3. The author himself flags the risk that an unmodeled signal is absorbed into solved-for parameters and states (Section 7) that the resulting zones 'may not be viewed as actual constraints.' This is the weakest load-bearing premise.
ad hoc to paper The factor-10 inflation of the formal uncertainties is sufficient to render them realistic.
Sections 3 and 7. The rescale is calibrated only to the worst case Pitjeva & Pitjev (2018) mentioned ('up to one order of magnitude larger'), so any additional systematic error would erase the P9/PY allowed regions.
domain assumption No other neglected or poorly modeled standard dynamical effect (asteroid/Kuiper belt masses, solar oblateness, GR, etc.) contaminates the comparison beyond what EPM2017 already absorbed.
Section 3 acknowledges that 'some other dynamical effect, whether standard or not, has been neglected or is poorly modeled' could bias any ephemeris-based constraints, including this one.
domain assumption The candidate-planet parameter ranges (masses, a, e, I) of Brown & Batygin (2021) and Siraj et al. (2025a,b) are taken at face value as the domains to test.
Sections 1 and 4. All conclusions are conditional on these hypothesized windows (e.g., a_9 ≤ 520 au; e_9 ∈ {0.259, 0.538}).

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Cite this review

Pith. "Pith review of Has Kronos devoured Planet Nine and its epigones?." pith.science (2026). https://pith.science/paper/XUYNCUJ6

@misc{pith2026260200802,
  author       = {Pith},
  title        = {Pith review of: Has Kronos devoured Planet Nine and its epigones?},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/XUYNCUJ6}},
  note         = {Machine review of arXiv:2602.00802}
}

read the original abstract

The Planet Nine hypothesis encompasses a body of about 5-8 Earth's masses whose orbital plane would be inclined to the ecliptic by one or two tens of degrees and whose perihelion distance would be as large as about 240-385 astronomical units. Recently, a couple of his epigones have appeared: Planet X and Planet Y. The former is a sort of minor version of Planet Nine in that all its physical and orbital parameters would be smaller. Instead, the latter would have a mass ranging from that of Mercury to the Earth's one and semimajor axis within 100-200 astronomical units. By using realistic upper bounds for the orbital precessions of Saturn, one can get insights on their position which, for Planet Nine, appears approximately confined around its aphelion. Planet Y can be just a Mercury-sized object at no less than about 125 astronomical units, while Planet X appears to be ruled out. Dedicated data reductions by modeling such perturber(s) are required to check the present conclusions, to be intended as hints of what might be detectable should planetary ephemerides include them. A probe on the same route of Voyager 1 would be perturbed by Planet Nine by about 20-40 km after some decades.

Figures

Figures reproduced from arXiv: 2602.00802 by the authors.

**Figure 1.** Allowed regions in the {fY, ΩY, ωY} parameter space for an elliptical orbit of a Mercury-mass Planet Y characterized by eY = 0.2 and different values of the semimajor axis aY (125 au, 150 au and 200 au) and the inclination IY (10◦ and 25◦ ) to the ecliptic. They were inferred by imposing that the theoretical rates of change of e, I, Ω, ϖ of Saturn due to Planet Y, calculated with Equations (1)–(7), simultaneously fu… view at source ↗

**Figure 2.** Allowed regions in the {f9, Ω9, ω9} parameter space for an elliptical orbit of a 5 m⊕ Planet Nine characterized by a9 = 520 au and different values of the eccentricity e9 (0.259 and 0.538) and the inclination I9 (11◦ and 21◦ ) to the ecliptic. They were inferred by imposing that the theoretical rates of change of e, I, Ω, ϖ of Saturn due to Planet Nine, calculated with Equations (1)–(7), simultaneously fulfil the co… view at source ↗

**Figure 3.** Allowed regions in the {f9, Ω9, ω9} parameter space for an elliptical orbit of a 8.4 m⊕ Planet Nine characterized by a9 = 520 au, e9 = 0.538 and different values of the inclination I9 (11◦ and 21◦ ) to the ecliptic. They were inferred by imposing that the theoretical rates of change of e, I, Ω, ϖ of Saturn due to Planet Nine, calculated with Equations (1)–(7), simultaneously fulfil the condition of Equation (18) by … view at source ↗

Figures from the paper (2 more)

**Figure 4.** Figure 4: Allowed regions in the {r9, α9, δ9} parameter space for an elliptical orbit of Planet Nine characterized by different values of its mass m9 (4.9 m⊕ and 8.4 m⊕). They were inferred by imposing that the theoretical Kronian rates of change of e, I, Ω, ϖ, referred to the …

**Figure 5.** Figure 5: Numerically produced time series ∆ρ(t), ∆α(t), ∆δ(t) of the signatures induced on the range ρ, RA and decl. of Voyager 1 from March 1986 to today by a P9 with m9 = 4.9 m⊕ (lef column) and m9 = 8.4 m⊕ (right column). They were obtained by integrating the barycentric equ…

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Works this paper leans on

6 extracted references · 6 canonical work pages

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Pith tools

Reviewed August 3, 2026 · model on record in the stance chip above.

[1] [1986]

doi: 10.1126/science.233.4759.39. C. A. Trujillo and S. S. Sheppard. A Sedna-like body with a perihelion of 80 astronomical units.Nature, 507:471–474, 2014. doi: 10.1038/nature13156. D. Turrini, R. Politi, R. Peron, D. Grassi, C. Plainaki, M. Barbieri, D. M. Lucchesi, G. Magni, F. Altieri, V . Cottini, N. Gorius, P. Gaulme, F.-X. Schmider, A. Adriani, and...

work page doi:10.1126/science.233.4759.39 2014

[2] [1987]

doi: 10.1029/JA092iA13p14873. E. C. Stone and E. D. Miner. The V oyager 2 Encounter with the Uranian System.Science, 233:39–43,

work page doi:10.1029/ja092ia13p14873

[3] [2017]

doi: 10.3847/1538-3881/153/2/63. S. S. Sheppard and C. A. Trujillo. New Extreme Trans-Neptunian Objects: Toward a Super-Earth in the Outer Solar System.Astron J., 152:221, 2016. doi: 10.3847/1538-3881/152/6/221. A. Siraj, C. F. Chyba, and S. Tremaine. Orbit of a Possible Planet X.Astrophys. J., 978(2):139, 2025a. doi: 10.3847/1538-4357/ad98f6. A. Siraj, C...

work page doi:10.3847/1538-3881/153/2/63 2016

[4] [2019]

doi: 10.1016/j.pss.2019.06.004. D. W. Hogg, G. D. Quinlan, and S. Tremaine. Dynamical Limits on Dark Mass in the Solar System. Astron J., 101:2274, 1991. doi: 10.1086/115849. M. J. Holman and M. J. Payne. Observational Constraints on Planet Nine: Astrometry of Pluto and Other Trans-Neptunian Objects.Astron J., 152:80, 2016a. doi: 10.3847/0004-6256/152/4/8...

work page doi:10.1016/j.pss.2019.06.004 2019

[5] [2020]

doi: 10.1007/s11214-020-00686-7. C. Shankman, J. J. Kavelaars, S. M. Lawler, B. J. Gladman, and M. T. Bannister. Consequences of a Distant Massive Planet on the Large Semimajor Axis Trans-Neptunian Objects.Astron J., 153:63,

work page doi:10.1007/s11214-020-00686-7

[6] [2022]

doi: 10.1038/d41586-022-01087-2. L. Xu, Y . Zou, and Y . Jia. China’s planning for deep space exploration and lunar exploration before 2030.Chin. J. Space Sci., 38:591–592, 2018. doi: 10.11728/cjss2018.05.591. L. Zwick, D. Soyuer, D. J. D’Orazio, D. O’Neill, A. Derdzinski, P. Saha, D. Blas, A. C. Jenkins, and L. Z. Kelley. Bridging the micro-Hz gravitatio...

work page doi:10.1038/d41586-022-01087-2