What Is the Solar Radiation Pressure (SRP) Force & Disturbance Torque Calculator?
Solar radiation pressure is the mechanical pressure exerted upon spacecraft surfaces by electromagnetic radiation from the Sun.
How Does the Solar Radiation Pressure (SRP) Force & Disturbance Torque Calculator Work?
Combines absorption and reflection photon momentum transfer equations at 1 AU (Solar constant 1361 W/m² / c = 4.56 µPa).
Solar Radiation Pressure (SRP) Force & Disturbance Torque Calculator Formula & Variables
The core mathematical equation utilized by this calculator is expressed as:
F = P_{ ext{srp}} A (1 + q) cos( heta), quad T = F cdot |mathbf{r}_{ ext{cp}} - mathbf{r}_{ ext{cg}}|
Photon momentum transfer force where P_srp = 4.56 µN/m² at 1 AU solar distance.
How to Use the Solar Radiation Pressure (SRP) Force & Disturbance Torque Calculator
- Enter surface area, reflectivity coefficient, solar incidence angle, and offset between center of pressure and center of gravity.
Step-by-Step Example Calculation
GEO Telecommunications Satellite Solar Array
Input Values:
surfaceAreaM2:12
reflectivityCoefficient:0.6
solarIncidenceAngleDeg:0
centerOfPressureOffsetM:0.25
Worked Steps: Solar force F = 87.6 µN; disturbance torque T = 21.9 µN·m accumulating ~1.89 N·m·s of momentum daily.
Understanding Your Result
Shows solar force in micro-Newtons and disturbance torque causing reaction wheel momentum buildup.
Factors That Affect the Result
- Solar sailing utilizes high-reflectivity sails to turn SRP from a disturbance into propulsive thrust.
When Should You Use This Calculator?
- GEO satellite stationkeeping propellant budgeting, deep-space trajectory modeling, and attitude momentum dumping planning.
Assumptions & Limitations
- Assumes flat planar surface at 1 AU Earth distance; ignores thermal re-radiation Yarkovsky forces.
Frequently Asked Questions
Calculation Accuracy & Reference Note
Standard astronautical solar radiation pressure formulation.