| 1. Domain | 1.1 Scope of the Domain | Boundaries | The range of phenomena the science includes and excludes. | Includes the study of planets, moons, rings, atmospheres, surfaces, interiors, orbital dynamics, climates, formation pathways, and exoplanet detection and characterization. Excludes stellar physics, galaxy scale dynamics, and cosmology except where they influence planetary formation or environment. |
| | Scale | The spatial, temporal, or organizational level at which the science operates (e.g., quantum, cellular, social, cosmic). | Operates from meter scale surface features to planetary radii and atmospheres thousands of kilometers across, and orbital scales from fractions of an astronomical unit to many astronomical units; time scales range from daily atmospheric cycles to billions of years of planetary evolution. |
| 1.2 Ontological Commitments | Entities | The kinds of things assumed to exist within the domain (particles, organisms, agents, fields, etc.). | Planets, moons, atmospheres, surfaces, cores, mantles, magnetic fields, ring systems, minor bodies, exoplanets, debris disks, and external influences such as host stars and stellar radiation. |
| | Properties | The fundamental attributes these entities possess (mass, charge, genotype, preference, etc.). | Mass, radius, density, temperature, albedo, composition, atmospheric pressure, orbital period, eccentricity, inclination, surface gravity, magnetic field strength, and internal heat flow. |
| | Categories | The basic ontological types used to classify domain elements (substances, processes, relations, structures). | Planet types, atmospheric regimes, surface processes, orbital architectures, formation pathways, and structural layers such as crust, mantle, and core. |
| 1.3 State-Variables | Variables | The measurable or definable properties that describe system conditions. | Temperature, pressure, density, atmospheric composition, orbital elements, surface features, internal heat production, stellar irradiation level, and rotation rate. |
| | Parameterization | How variables encode and represent the system’s state. | States encoded using atmospheric profiles, mass and radius measurements, spectral signatures, orbital solutions, interior structure models, and climate energy balance descriptors. |
| 1.4 Admissible Idealizations | Simplifications | Conceptual reductions used to make the domain tractable (point masses, rational agents, perfect gases). | Spherical planet approximation, hydrostatic equilibrium, uniform atmosphere assumptions, ideal gas approximations, simplified chemistry, point mass orbits, and treating climates as one dimensional for modeling. |
| | Validity Conditions | The limits and contexts in which idealizations hold or break down. | Valid when rotation is moderate, atmosphere is stable, chemical reactions are slow relative to mixing, orbits are not strongly perturbed, and the climate is not dominated by chaotic behavior or extreme external forcing. |
| 1.5 Domain Assumptions | Structural Assumptions | Background ontological stances such as determinism, continuity, randomness, discreteness. | Assumes planets follow gravitational and thermodynamic laws, atmospheres behave as fluids, interiors evolve according to known physical rules, and exoplanet detection signals represent real orbital or atmospheric properties. |
| | Implicit Commitments | Unstated but necessary assumptions that shape the field’s conceptual structure. | Assumes simplified atmospheric and interior models capture key physics, orbital dynamics reliably reflect gravitational interactions, and observable signatures such as transits or spectra map correctly onto physical parameters. |
| 1.6 Internal Coherence Requirements | Consistency | The demand that domain concepts do not contradict one another. | Requires agreement among orbital measurements, atmospheric spectra, internal structure models, mass radius relationships, and surface or climate behavior. |
| | Compatibility | The requirement that entities, variables, and assumptions fit together into a unified descriptive framework. | Entities, variables, and assumptions must unify orbital motion, internal structure, atmospheric processes, surface behavior, and long term evolution into a coherent physical description of planetary systems. |
| 2. Evidence Layer | 2.1 Observable Phenomena | Observables | The aspects of the domain that can produce detectable signals accessible to measurement. | Detectable signals include planetary transits, radial velocity shifts, direct imaging brightness, thermal emission, reflected light curves, planetary spectra, orbital motion, surface composition signatures, atmospheric absorption features, phase curves, and timing variations. |
| | Detection Limits | The boundaries of what can be resolved or sensed by current instruments or methods. | Limited by telescope sensitivity, star planet contrast ratios, angular resolution, atmospheric interference for ground data, instrument noise, photon noise, and the ability to detect small planets or long period orbits. |
| 2.2 Measurement Systems | Units | Standardized quantifications (meters, seconds, volts, decibels, dollars, etc.) necessary for consistent comparison. | Uses meters, seconds, astronomical units, Earth or Jupiter mass units, Earth or Jupiter radius units, kelvins, magnitudes, flux units, orbital period in days or years, and velocities in kilometers per second. |
| | Instruments | Devices and tools (microscopes, spectrometers, sensors, surveys, detectors) used to produce measurements. | Instruments include space telescopes, ground telescopes, spectrographs, photometers, interferometers, coronagraphs, adaptive optics systems, radial velocity spectrometers, and infrared or ultraviolet detectors. |
| 2.3 Operational Definitions | Definitions | Terms defined by specific measurement procedures, ensuring empirical clarity. | Quantities such as transit depth, radial velocity amplitude, atmospheric composition indicators, equilibrium temperature, orbital inclination, albedo, and mass radius relationships are defined by standardized observational procedures. |
| | Procedures | The explicit steps required to perform a measurement in a reproducible way. | Procedures include extracting light curves, fitting transit models, measuring radial velocity shifts, performing spectral retrieval, conducting direct imaging reductions, and correcting for stellar variability or instrument drift. |
| 2.4 Data Acquisition | Protocols | Formal processes for gathering data under controlled or standardized conditions. | Data gathered using long duration monitoring, repeated transits, multi wavelength spectroscopy, scheduled follow up observations, direct imaging sequences, and coordinated observations across multiple instruments. |
| | Sampling | Rules determining which subset of the domain is measured and how representative it is. | Sampling rules include multiple transit sampling, high cadence photometry, wavelength binning for spectroscopy, repeated orbital phase coverage, and validation via independent observation epochs. |
| 2.5 Data Character & Format | Data Types | The form raw evidence takes (time series, spectra, images, counts, qualitative records). | Data appears as transit light curves, radial velocity time series, spectra, direct images, temperature maps, orbital catalogs, phase curves, and atmospheric retrieval outputs. |
| | Resolution | The granularity or precision with which data is captured. | Determined by detector sensitivity, time sampling accuracy, spectral dispersion, angular resolution in imaging, mechanical stability of instruments, and atmospheric transparency for ground based surveys. |
| 2.6 Reliability & Calibration | Calibration | Adjustment procedures ensuring instruments produce accurate results. | Calibration uses reference stars, flat field corrections, dark and bias frames, wavelength calibration sources, pointing corrections, thermal background subtraction, and cross calibration across instruments or surveys. |
| | Error Characterization | Identification and quantification of noise, uncertainty, bias, and measurement error. | Errors arise from stellar activity, photon noise, instrument drift, atmospheric distortion, contamination from nearby stars, transit timing uncertainty, and degeneracy in spectral retrieval or orbital fits. |
| 3. Structural Layer | 3.1 Patterns & Regularities | Laws / Relations | Stable, repeatable patterns governing how observables behave across conditions. | Stable patterns include mass radius relations, temperature distance laws, atmospheric escape trends, star planet interaction rules, density composition correlations, orbital stability conditions, and climate energy balance patterns. |
| | Invariants | Quantities or properties that remain constant under transformations (symmetries, conservation laws). | Invariants include conservation of angular momentum in planetary orbits, conserved orbital resonances, stable density composition relationships, persistent atmospheric ratios under equilibrium, and long term internal structural layers. |
| 3.2 Causal Architecture | Mechanisms | Underlying processes or structures that produce the observed regularities. | Mechanisms arise from gravitational attraction, stellar irradiation, atmospheric chemistry, internal heat flow, accretion in protoplanetary disks, tidal interactions, and long term climate evolution. |
| | Pathways | Organized sequences of interactions forming a causal chain or network. | Pathways include planet formation by accretion, orbital migration, atmosphere formation and loss, surface evolution, geology climate feedback loops, and long term orbital and rotational evolution. |
| 3.3 Theoretical Vocabulary | Concepts | Core terms that encode the domain’s structure (force, gene, equilibrium, field). | Core terms include transit, radial velocity, albedo, equilibrium temperature, exosphere, atmospheric retrieval, habitable zone, protoplanetary disk, escape velocity, and orbital resonance. |
| | Classifications | Taxonomies, categories, or typologies that organize entities and relations. | Classifies planets by size, mass, composition, atmosphere type, orbital regime, temperature regime, and by categories such as terrestrial, gas giant, ice giant, sub Neptune, hot Jupiter, or super Earth. |
| 3.4 Formal Representations | Equations | Mathematical constructs expressing laws, relations, or mechanisms. | Includes orbital mechanics equations, mass radius relationships, energy balance equations, atmospheric scale height formulas, escape rate equations, and climate or interior structure equations. |
| | Models | Structured representations—mathematical, computational, or conceptual—used to predict and explain phenomena. | Uses climate models, atmospheric retrieval models, internal structure models, disk formation models, orbital evolution simulations, and habitability assessment frameworks. |
| 3.5 Idealized Structures | Simplified Models | Purposeful abstractions that capture essential dynamics while omitting irrelevant detail. | Idealizations include spherical planets, uniform atmospheres, circular orbits, perfect blackbody emission, simplified chemistry, no clouds, and uniform surface assumptions. |
| | Limit Conditions | Regimes where specific models or approximations hold (classical vs. quantum, linear vs. nonlinear). | Models valid when atmospheres are stable, eccentricity is low, stellar forcing changes gradually, rotation is moderate, and cloud cover or surface variability are limited; they break down in extreme or chaotic regimes. |
| 3.6 Integrative Frameworks | Unifying Theories | Higher-order structures that connect disparate laws or mechanisms under a coherent whole. | Includes frameworks linking planetary formation, orbital dynamics, interior physics, atmospheric behavior, climate models, and star planet interaction into a unified system description. |
| | Interdisciplinary Links | Points where the theory connects to adjacent sciences or larger explanatory systems. | Links to astronomy, atmospheric science, geology, chemistry, fluid dynamics, climate science, remote sensing, and astrobiology. |
| 4. Method Layer | 4.1 Inquiry Design | Experimental Design | Structured plans for manipulating variables to test causal claims. | Direct manipulation of planets is impossible; instead, designs involve selecting systems by stellar type, orbit, or atmospheric features to isolate causal effects. Experiments include comparing planets at different orbital distances, around different star types, or with different atmospheric compositions. |
| | Observational Design | Systematic approaches for gathering non-manipulated data (surveys, field studies, natural experiments). | Observational strategies include long term transit monitoring, high cadence radial velocity surveys, multi wavelength spectroscopy, direct imaging campaigns, and natural experiments such as eclipses or atmospheric escape events. |
| 4.2 Testing & Validation | Hypothesis Testing | Procedures for evaluating whether evidence supports or contradicts specific claims. | Hypotheses tested by comparing observed transit data, radial velocity curves, spectra, temperature maps, phase curves, and orbital evolution patterns with predictions from atmospheric, interior, or dynamical models. |
| | Replication | The requirement that results be independently reproducible under similar conditions. | Replication requires repeat transit observations, independent radial velocity detections, confirmation with different instruments, reanalysis using independent pipelines, and verification across multiple epochs. |
| 4.3 Inference & Evaluation | Statistical Inference | Rules for drawing conclusions from noisy or incomplete data. | Statistical methods include light curve fitting, orbital parameter estimation, spectral retrieval, noise modeling, significance testing of planet signals, and uncertainty quantification for atmospheric or interior properties. |
| | Model Comparison | Criteria (fit, simplicity, predictive accuracy, robustness) used to evaluate competing models. | Models compared by fit quality, ability to reproduce multi wavelength data, physical plausibility, robustness across observational conditions, and agreement with independent mass or radius measurements. |
| 4.4 Error Management | Error Analysis | Identification and quantification of random and systematic errors. | Errors arise from stellar variability, photon noise, atmospheric distortion, detector drift, incomplete transit sampling, instrument systematics, and degeneracies in atmospheric retrieval or orbital fitting. |
| | Bias Control | Methods for minimizing subjective, instrumental, or procedural biases. | Bias minimized through blind fitting, detrending of stellar activity, cross calibration of instruments, independent validation of retrieval outputs, and correction for observational selection effects. |
| 4.5 Adjudication & Revision | Peer Scrutiny | Collective evaluation of claims through critique, review, and debate. | Findings scrutinized through peer review, cross survey confirmation, conference critique, independent reanalysis, and comparisons with climate, interior, or orbital evolution models. |
| | Theory Revision | Procedures for modifying, replacing, or discarding models based on new evidence. | Theories revised when data reveal unexpected densities, anomalous spectra, unstable orbits, unusual temperature patterns, or unpredicted atmospheric chemistry; prompting updates to formation, interior, or atmospheric models. |
| 4.6 Integrity Conditions | Transparency | Requirements to disclose methods, data, assumptions, and limitations. | Requires full disclosure of calibration steps, data reduction pipelines, noise models, orbital fitting assumptions, retrieval parameters, and any limitations or uncertainties in detection or interpretation. |
| | Ethical Standards | Norms ensuring responsible conduct in experimentation, data handling, and publication. | Requires accurate reporting, transparency in catalog construction, avoidance of selective data omission, responsible use of telescope resources, and adherence to professional research standards in planetary science. |