use sciforge::hub::domain::meteorology::radiation::stefan_boltzmann_flux;
use crate::{
MU_0, SOLAR_EFFECTIVE_TEMP, SOLAR_LUMINOSITY,
SOLAR_MAGNETIC_FIELD_SUNSPOT_T, SOLAR_RADIUS, SUNSPOT_PENUMBRA_TEMP, SUNSPOT_UMBRA_TEMP,
};
pub const SUNSPOT_MIN_DIAMETER_M: f64 = 2.5e6;
pub const SUNSPOT_MAX_DIAMETER_M: f64 = 5e7;
pub const SUNSPOT_LIFETIME_SCALE_DAYS: f64 = 10.0;
pub const ZURICH_NUMBER_SCALE: f64 = 10.0;
pub const WOLF_NUMBER_K: f64 = 0.6;
pub const BUTTERFLY_LATITUDE_MAX_DEG: f64 = 35.0;
pub const BUTTERFLY_LATITUDE_MIN_DEG: f64 = 5.0;
pub const MAUNDER_MINIMUM_SSN: f64 = 0.0;
pub const MODERN_MAXIMUM_SSN: f64 = 190.0;
pub const JOY_LAW_TILT_COEFF: f64 = 0.5;
pub struct Sunspot {
pub latitude_deg: f64,
pub longitude_deg: f64,
pub diameter_m: f64,
pub umbra_temperature_k: f64,
pub penumbra_temperature_k: f64,
pub magnetic_field_t: f64,
pub polarity: i8,
}
impl Default for Sunspot {
fn default() -> Self {
Self::typical()
}
}
impl Sunspot {
pub fn typical() -> Self {
Self {
latitude_deg: 15.0,
longitude_deg: 0.0,
diameter_m: 2e7,
umbra_temperature_k: SUNSPOT_UMBRA_TEMP,
penumbra_temperature_k: SUNSPOT_PENUMBRA_TEMP,
magnetic_field_t: SOLAR_MAGNETIC_FIELD_SUNSPOT_T,
polarity: 1,
}
}
pub fn large() -> Self {
Self {
latitude_deg: 12.0,
longitude_deg: 45.0,
diameter_m: SUNSPOT_MAX_DIAMETER_M,
umbra_temperature_k: 3500.0,
penumbra_temperature_k: 4300.0,
magnetic_field_t: 0.4,
polarity: -1,
}
}
pub fn umbra_area_m2(&self) -> f64 {
let r = self.diameter_m * 0.2;
std::f64::consts::PI * r * r
}
pub fn penumbra_area_m2(&self) -> f64 {
let r_total = self.diameter_m / 2.0;
let r_umbra = self.diameter_m * 0.2;
std::f64::consts::PI * (r_total * r_total - r_umbra * r_umbra)
}
pub fn total_area_m2(&self) -> f64 {
let r = self.diameter_m / 2.0;
std::f64::consts::PI * r * r
}
pub fn area_millionths_hemisphere(&self) -> f64 {
let hemisphere = 2.0 * std::f64::consts::PI * SOLAR_RADIUS * SOLAR_RADIUS;
self.total_area_m2() / hemisphere * 1e6
}
pub fn umbra_flux(&self) -> f64 {
stefan_boltzmann_flux(self.umbra_temperature_k)
}
pub fn penumbra_flux(&self) -> f64 {
stefan_boltzmann_flux(self.penumbra_temperature_k)
}
pub fn photosphere_flux(&self) -> f64 {
stefan_boltzmann_flux(SOLAR_EFFECTIVE_TEMP)
}
pub fn luminosity_deficit(&self) -> f64 {
let f_photo = self.photosphere_flux();
let f_umbra = self.umbra_flux();
let f_penumbra = self.penumbra_flux();
(f_photo - f_umbra) * self.umbra_area_m2()
+ (f_photo - f_penumbra) * self.penumbra_area_m2()
}
pub fn brightness_contrast(&self) -> f64 {
self.umbra_flux() / self.photosphere_flux()
}
pub fn magnetic_pressure(&self) -> f64 {
self.magnetic_field_t.powi(2) / (2.0 * MU_0)
}
pub fn magnetic_energy(&self) -> f64 {
let volume = self.total_area_m2() * 1e7;
self.magnetic_field_t.powi(2) * volume / (2.0 * MU_0)
}
pub fn wilson_depression_m(&self) -> f64 {
let p_mag = self.magnetic_pressure();
let rho = 2e-4;
let g = 274.0;
p_mag / (rho * g)
}
pub fn evershed_flow_speed(&self) -> f64 {
2000.0
}
pub fn estimated_lifetime_days(&self) -> f64 {
let area_msh = self.area_millionths_hemisphere();
0.1 * area_msh
}
pub fn joy_law_tilt_deg(&self) -> f64 {
JOY_LAW_TILT_COEFF * self.latitude_deg.abs()
}
}
pub struct SunspotCycle {
pub cycle_number: u32,
pub phase: f64,
pub ssn_max: f64,
}
impl SunspotCycle {
pub fn current_ssn(&self) -> f64 {
self.ssn_max * (std::f64::consts::PI * self.phase).sin().max(0.0)
}
pub fn activity_level(&self) -> &'static str {
let ssn = self.current_ssn();
if ssn < 20.0 {
"Minimum"
} else if ssn < 80.0 {
"Low"
} else if ssn < 150.0 {
"Moderate"
} else {
"Maximum"
}
}
pub fn butterfly_latitude_deg(&self) -> f64 {
let max = BUTTERFLY_LATITUDE_MAX_DEG;
let min = BUTTERFLY_LATITUDE_MIN_DEG;
max - (max - min) * self.phase
}
pub fn f107_index(&self) -> f64 {
67.0 + 0.572 * self.current_ssn()
}
pub fn tsi_variation_wm2(&self) -> f64 {
0.1 * (self.current_ssn() / 100.0)
}
pub fn total_solar_irradiance(&self) -> f64 {
1361.0 + self.tsi_variation_wm2()
}
}
pub fn wolf_number(groups: u32, individual_spots: u32) -> f64 {
WOLF_NUMBER_K * (ZURICH_NUMBER_SCALE * groups as f64 + individual_spots as f64)
}
pub fn sunspot_number_to_area_msh(ssn: f64) -> f64 {
16.7 * ssn
}
pub fn maunder_minimum_cycle() -> SunspotCycle {
SunspotCycle {
cycle_number: 0,
phase: 0.5,
ssn_max: MAUNDER_MINIMUM_SSN,
}
}
pub fn cycle_25() -> SunspotCycle {
SunspotCycle {
cycle_number: 25,
phase: 0.45,
ssn_max: 150.0,
}
}
pub fn sporer_law_latitude(phase: f64) -> f64 {
BUTTERFLY_LATITUDE_MAX_DEG * (1.0 - phase)
}
pub fn active_region_probability(ssn: f64) -> f64 {
1.0 - (-ssn / 100.0).exp()
}
pub fn facular_brightening(ssn: f64) -> f64 {
0.0011 * ssn
}
pub fn total_luminosity_variation(ssn: f64) -> f64 {
let spot_dimming = -0.0003 * ssn;
let facular = facular_brightening(ssn);
SOLAR_LUMINOSITY * (1.0 + spot_dimming + facular)
}