Astrophysics: Addon for Astrocraft

🌌 Astrophysics: Spacetime Simulation Engine

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Upgrade your Astrocraft experience into a state-of-the-art astrophysical, differential spacetime, and deep-time climate simulation. Astrophysics transcends traditional graphical sky tweaks—it is a comprehensive, client-side & Server cosmic simulation framework that fundamentally overhaulates Minecraft’s physical reality using first-principles Einsteinian general relativity tensor approximations, true astronomical rotational kinematics, multi-body barycentric orbital mechanics, Newtonian continuum physics, and secular astronomical climate forcing cycles. It completely deprecates Astrocraft's static legacy approximations in favor of a mathematically rigorous, living astrophysical universe.

NOTE: My mod have milancovitch cycels one of the cycles make ice ages wich is right, but this cycle does not have support serene seasons or fabric seasons, so its need another developer make a mod to make it work and support this feature and make winter take so long time like ice ages in real-life.

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⚡ A First-Principles Cosmological Simulation Matrix
Architected from the ground up as an advanced mathematical physics engine, Astrophysics translates static orbital scripts into dynamic vector-based differential equations, governed by genuine gravitational field potentials, resonant multi-body couplings, and atmospheric radiative transfer optics.

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⚠️ Important Compatibility Features

• Global Longitude (Astrocraft): Features like the zodiacal light, starlight dimming from the moon, or other related features do not synchronize well with longitudes. You must either turn off longitudes or disable those non-synchronized features to prevent visual desyncs and errors.

• Global Latitude (Astrocraft): The mod works very well with latitudes, and you likely won't need to turn it off or disable some of my mod features.

• Lunar Synchronization: Match the lunar month duration (orbital period) in both Astrophysics and Astrocraft configs to prevent shader and rendering desyncs.

• Sodium Compatibility: If using Sodium, disable "Zodiacal Light" in the config to prevent lighting issues and black sky dots.

• Axial Precession: Due to the base mod's design, the Axial Precession feature does not naturally synchronize with custom additions like Zodiacal Light or Rayleigh & Mie twilight colors. To achieve perfect alignment, disable either Axial Precession or those specific features.

• Tidal Deceleration & Feature Synchronization: Planetary rotational slowdown (Tidal Deceleration) naturally operates independently from fixed optical features like Zodiacal Light, Rayleigh & Mie twilight colors, and lunar starlight dimming. If visual desyncs occur, either disable Enable Tidal Deceleration or toggle off those specific non-synchronized features.

• More Realistic Skies Compatibility: Using More Realistic Skies alongside Astrophysics causes visual and rendering errors like light pullotion color. It is strongly recommended not to use them together.

• NOTE: Might my mod have another visuals bugs not because my mod, because how astrocraft classes build and work, i already fixed a lot of them, but some of them are unfixable.

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✨ Core Features & Cosmic Engine Physics 🌌 Spacetime Curvature & Multi-Body Gravitational Coupling

• Scientific Model: Implements weak-field approximations of Einstein's General Relativity Field Equations, completely replacing Astrocraft's pre-calculated legacy gravity with true relativistic spacetime curvature between celestial bodies, dynamically driven by the actual masses of planets, moons, and the Sun. Coupled with advanced multi-body barycentric mechanics, celestial bodies exert mutual gravitational forces on one another.
• In-Game Effect: With gravity now dynamically calculated across world space and astronomical spacetime, celestial bodies exert mutual gravitational influences on one another through advanced multi-body coupling. This results in realistic orbital wobbles, subtle fluctuations in day-night cycle timings, and authentic stellar positioning governed by real-world astrophysical principles.

🌠 Aurora Borealis & Earth's Magnetic Shield

• Scientific Model: Introduces Earth's magnetic shield and magnetosphere framework, integrating atmospheric thermal convection dynamics and mapping the physical interactions of solar wind plasma, solar flares, and solar flames (coronal mass ejections) against planetary magnetic induction lines, governed by a realistically fluctuating solar activity cycle.
• In-Game Effect: Adds the Aurora Borealis exclusively above latitude 50 or less latitude -50. Its brilliant visual curtains and atmospheric glows dynamically scale with real-life-like periodic changes in solar activity, solar flares, and flare intensity hitting Earth over time, while being realistically dimmed and modulated by moonlight and local light pollution. Additionally, as the aurora's brightness and intensity peak, it increases the extent of background stars, planets, and deep-sky objects obscured by its luminous atmospheric radiance.

🌍 Newtonian Surface Dynamics & Earth Gravity

• True Earth Rotational Kinematics: The mod introduces a true, fully functional planetary rotation to Minecraft—the world actually spins on its axis in real-time, actively and dynamically influencing gameplay, celestial movement, and environmental physics.
• Coriolis Force Simulation: Simulates the apparent deflection of moving entities, trajectories, and projectiles caused by the Earth's axial spin, with deflection intensity scaling dynamically based on your geographic position.
• Rotational Centrifugal Force: Replicates the outward inertial force driven by Earth's rotation, which slightly counteracts and reduces downward gravitational pull near the equator.
• Observer & Dynamic Latitude Calibration: All rotational mechanics, Coriolis trajectories, and celestial calculations seamlessly integrate with either the manual Observer Latitude (°) configuration option or Use Globe Latitude setting—which dynamically computes latitude based on the player's world Z-coordinate—allowing players to choose between precise geographic positioning or manual calibration.
• Scientific Model: Formulated upon classical Newtonian Mechanics and Universal Gravitation (governed by F = ma and multi-body gravitational attraction vectors), applying precise Earth-standard surface free-fall acceleration (g ≈ 9.81 m/s²) coupled with quadratic aerodynamic drag equations and unconstrained vertical velocity limits, completely superseding vanilla Minecraft's hard-coded velocity clamping caps.
• In-Game Effect: Entities experience continuous, uninhibited acceleration profiles during atmospheric free-fall—faithfully adhering to real-world ballistic physics—while fluid dynamics overhaulates transform aquatic interactions; swimming incorporates realistic hydrodynamic drag, water viscosity, and buoyancy resistance, rendering aquatic traversal significantly more tactical, physically demanding, and dependent on precise momentum management.

⏱️ Tidal Deceleration & Planetary Slowdown

• Scientific Model: Simulates the gradual rotational slowing of the planet caused by tidal friction, gravitational drag, and energy dissipation within the Earth-Moon system over time.
• In-Game Effect: Progressively reduces planetary rotation speed, altering day lengths and interacting directly with rotational physics. Note on Synchronization: Because this dynamic slowdown changes planetary rotation independently, it does not naturally synchronize with fixed optical features like the Zodiacal Light, Rayleigh & Mie twilight colors, and lunar starlight dimming/attenuation. If you experience visual mismatches, simply disable Enable Tidal Deceleration or toggle off those specific non-synchronized features.

🪐 Multi-Body Barycentric Wobble & Resonance

• Scientific Model: Leverages dynamic Barycentric Mechanics (calculating true multi-body center-of-mass vectors) combined with advanced Orbital Resonance Locking frameworks (including the critical spin-orbit resonance lock) — mirroring the intricate gravitational locking seen between Neptune's inner moons Naiad and Thalassa (maintaining precise orbital harmony) and Mercury's 3:2 spin-orbit resonance with the Sun, alongside the classic 4:2:1 Laplace Orbital Resonance framework.
• In-Game Effect: Replicates complex orbital harmony, gravitational inter-body coupling, resonance locking effects, and system-wide barycentric wobbles across the star system, dynamically shifting apparent solar positions, orbital paths, and satellite interactions based on true multi-body physics.

🌙 Lunar Recession & Earth's Equatorial Bulge

• Scientific Model: Applies Tidal Torque Conservation of Angular Momentum (~3.8 cm/year secular orbital expansion via tidal dissipation) alongside Maclaurin/Jacobi Ellipsoid Centrifugal Bulge Equations (quantifying Earth's equatorial bulge, where planetary rotation induces an oblate spheroid geometry and mass redistribution acting against self-gravitational potential energy).
• In-Game Effect: The Moon's apparent angular diameter gradually contracts over deep timescales (transitioning total solar eclipses into annular ones), while the equatorial bulge and mass distribution interact with lunisolar gravity to drive long-term axial precession torques.

🪐 Gyroscopic Precession & Milankovitch Cycles

• Scientific Model: Implements comprehensive astronomical Milankovitch Climate Forcing Cycles (directly responsible for Earth's deep-time ice ages), rigorously modeling the ~25,772-year lunisolar gyroscopic axial precession period, obliquity variations, and the 100,000-year orbital eccentricity modulation cycle where the massive gravitational perturbations of Jupiter and Saturn stretch and elongate Earth's orbit into a more elliptical trajectory, contrasted by the Sun's gravitational pull which periodically draws and relaxes Earth's orbit back toward a near-circular geometry.
• In-Game Effect: Drifts celestial poles across geological epochs, recalibrates the true North Star, and drives cyclic ice age regimes; as Jupiter, Saturn, and the Sun continuously reshape Earth's orbital stretch, it causes sweeping distance variations that directly alter the apparent angular size of the Sun's disk in the sky, dynamically impacts sky lighting, reshapes stellar visibility, and governs every planetary, climatic, and cosmic aspect of the simulation.

☀️ Solar Analemma & Barycentric Orbit

• Scientific Model: Combines Keplerian Orbital Mechanics (Kepler's First Law of elliptical orbits and Second Law of equal areal velocity vectors) with the geometric interplay of Earth's axial obliquity and orbital eccentricity, solving the precise Equation of Time components.
• In-Game Effect: The Sun traces a mathematically exact, asymmetric figure-8 analemma curve across the sky over an annual cycle, reflecting variations in solar transit speed and declination, while synchronized atmospheric optical scattering dynamically handles stellar magnitude attenuation and daylight contrast.

🎈 Atmospheric Pressure & Barometric Altitudes

• Scientific Model: Integrates the Barometric Formula derived from Hydrostatic Equilibrium Equations coupled with temperature lapse-rate profiles, dynamically computing exponential atmospheric pressure decay across extreme high-altitude tropospheric/stratospheric boundaries alongside linear hyperbaric compression models for deep subterranean crustal depths.
• In-Game Effect: Crossing structural altitude thresholds or descending past subterranean depth baselines triggers rigorous barometric stress calculations; this dynamically depletes alveolar oxygen partial pressure, simulating severe high-altitude hypoxia or deep-crustal hyperbaric pressure imbalances resulting in progressive cellular and suffocation damage.

🔒 Tidal Locking

• Scientific Model: Formulates permanent Spin-Orbit Resonance Coupling (such as synchronous 1:1 and asymmetric 3:2 states) governed by gravitational tidal torque acting on a moon's triaxial mass distribution.
• In-Game Effect: Synchronously locked celestial bodies maintain a permanent primary hemisphere facing their parent world, preventing static rigidity and mimicking true astronomical dynamics.

✨ Lunar Glare & Atmospheric Scintillation

• Scientific Model: Implements Kolmogorov Turbulence Theory and the Atmospheric Scintillation Index to compute density-driven refractive index fluctuations for starlight, integrated with phase-dependent lunar illuminance extinction functions and sky background radiance models accounting for Rayleigh and Mie scattering of moonlight across airmass columns.
• In-Game Effect: High-phase lunar illuminance dynamically scales sky brightness and glare—washing out faint stellar magnitudes just like real-world dark-sky degradation—while lower atmospheric density gradients induce authentic stellar twinkling (scintillation) that naturally stabilizes and vanishes in absolute space vacuum environments.

🌆 Light Pollution & Skyglow Scattering

• Scientific Model: Integrates the official Bortle Dark-Sky Scale (Class 1 to Class 9) paired with artificial luminance diffusion matrices, computing volumetric ground-level block-light emission radiance, horizontal light trespass propagation, and altitude-dependent aerosol scattering/attenuation coefficients across urban-to-wilderness gradients.
• In-Game Effect: High block-light levels and low elevations dim deep-sky objects, introducing realistic light domes over populated regions and heavily rewarding players who seek out pristine dark-sky mountain elevations for stargazing.

🌅 Rayleigh Sunrise & Sunset Gradients

• Scientific Model: Utilizes Rayleigh Optical Scattering Physics (where scattering intensity scales inversely with the fourth power of wavelength), combined with airmass optical depth path-length integration at low solar elevation angles, Chappuis ozone absorption profiles, and multi-layered atmospheric chromatic dispersion models.
• In-Game Effect: Completely supersedes vanilla horizon blending with smooth, physically accurate twilight luminance and chromatic separation gradients, spanning civil, nautical, and astronomical twilight phases.

✨ Zodiacal Light & Interplanetary Dust

• Scientific Model: Applies Mie and Rayleigh Interplanetary Dust Forward-Scattering Optics alongside coordinate transformation algorithms to simulate sunlight reflection off micrometeoroidal cosmic dust aligned with the orbital ecliptic plane, accounting for observer latitude geometry.
• In-Game Effect: Renders a subtle, realistic celestial band visible before sunrise and after sunset during twilight under dark-sky conditions, with its tilt dynamically adapting based on your current latitude—whether through dynamic world-space position calculations or manual configurations—adding unprecedented astronomical realism.

☀️ Realistic Solar Glare & Atmospheric Scattering

• Photorealistic Optical Simulation: Completely replaces the vanilla solar asset with an advanced solar glare model designed to emulate real-world atmospheric optics and scattering principles.
• High-Luminance Attenuation: Incorporates intense luminance thresholds during peak daylight hours, naturally obscuring the solar disc and rendering it fully resolvable only near the horizon as airmass and optical depth increase—mirroring actual atmospheric physics.

🌙 Realistic Lunar Phases & Phase-Adaptive Glare

• Selenological Accuracy: Overhaulates the default lunar texture to deliver scientifically accurate, true-to-life orbital phases based on exact orbital mechanics.
• True Earth Shadow Projection: The enhanced lunar texture accurately projects a true Earth shadow onto the moon's surface, reflecting realistic astronomical shadow casting, umbral/penumbral transitions, and alignment mechanics during lunar phases and eclipses.
• Dynamic Luminance Scaling: Features an immersive, phase-adaptive glare mechanism where the optical halo and luminescence intensity dynamically scale in real-time according to the moon's current illumination cycle.

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⚙️ Customization & Configuration

Fully configurable via Cloth Config and Mod Menu through a clean, streamlined 5-tab layout matching your astronomical controls:

☀️ Sun / Moon Tab

• Solar Physics Options: Solar Barycentric Wobble, Solar Wobble Velocity, Barycentric Orbit Radius, Figure-8 Analemma Pattern, and Realistic Eclipse & Solar Star Dimming.
• Lunar Mechanics Options: Phase Starlight Attenuation, Synodic Lunar Month (Days), Suppress Lunar Glare in Space.

🌌 Atmosphere Tab

• Atmospheric Fog: Tropospheric Fog Attenuation, Fog Start Altitude (Y), Fog End Altitude (Y), and Rayleigh & Mie Twilight Colors.
• Light Pollution: Light Pollution (Bortle) and Urban Skyglow Multiplier.
• Starlight Scintillation: Starlight Scintillation (Toggle), Scintillation Intensity, Scintillation Speed, and Dampen Scintillation in Space.
• Zodiacal Light: Zodiacal Dust Band and Interplanetary Dust Intensity.
• Aurora Borealis Mechanics: Enable Aurora Display, Aurora Cycle Interval (Days), Enable Aurora Altitude Fade, Aurora Fade Start Height, and Aurora Fade End Height.

⏱️ Milankovitch Cycles Tab

• Axial Precession: Manage Axial Precession Dynamics and Precession Period (Days).
• Obliquity Oscillation: Fine-tune Obliquity Oscillation toggles and Obliquity Period (Days).
• Eccentricity Modulation: Scale Eccentricity Climate Modulation, Elliptical Stretch Multiplier, Glacial Cycle Period (Years), and Restrict Dynamics to Overworld.

🌍 Earth Mechanics Tab

• Atmospheric Pressure: Configure Enable Atmospheric Pressure, Maximum Altitude Threshold, and Minimum Altitude Threshold.
• Gravity & Aerodynamics: Calibrate Realistic Free-Fall Gravity, Surface Gravity (g ≈ 9.81 m/s²), Use Globe Latitude, Observer Latitude (°), Coriolis Force Simulation, Rotational Centrifugal Force, and Atmospheric Drag (Cd).
• Earth-Moon Dynamics: Manage Apparent Lunar Recession, Lunar Recession Rate Multiplier, Enable Tidal Deceleration, and Tidal Time Constant (Speed).

🪐 Spin-Orbit Resonance Tab

• Multi-Body Resonances: Configure Tidal Locking, Laplace Resonance System, General Orbital Resonances, and Orbital Perturbation Multiplier.

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📦 Requirements & Compatibility

• Core Dependencies:
  • Fabric API
  • Astrocraft (v1.5.1 Only)
  • Cloth Config API
• Forge / NeoForge Support: Fully compatible using Sinytra Connector and Forgified Fabric API.
• Recommended Additions:
  • Mod Menu

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📜 Credits & Acknowledgments

• Me (PixelFlux) — Creator and main developer of Astrophysics (Licensed under MIT).
• Pymsrps — Creator of the original Astrocraft mod (Licensed under MIT).
• shedaniel — Creator of Cloth Config API.
• Terraformers — Developer of Mod Menu.
• Sinytra — Creators of Sinytra Connector & Forgified Fabric API.
• modmuss50 — Creator and maintainer of Fabric API.