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Star Tracker updates.

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Add sky temperature calculation.
Add Solar flux plot.
Add .gitattributes so .fits files are treated as binary.
This commit is contained in:
Jon Beniston
2021-01-29 12:57:58 +00:00
parent 52b51feded
commit d80087b974
36 changed files with 11995 additions and 465 deletions
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sdrbase/util/astronomy.cpp
+55
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@@ -492,6 +492,61 @@ double Astronomy::lstAndRAToLongitude(double lst, double raHours)
return -longitude; // East positive
}
// Return right ascension and declination of North Galactic Pole in J2000 Epoch
void Astronomy::northGalacticPoleJ2000(double& ra, double& dec)
{
ra = 12 + 51.4 / 60.0;
dec = 27.13;
}
// Convert from equatorial to Galactic coordinates, J2000 Epoch
void Astronomy::equatorialToGalactic(double ra, double dec, double& l, double& b)
{
const double raRad = Units::degreesToRadians(ra * 15.0);
const double decRad = Units::degreesToRadians(dec);
// Calculate RA and dec for North Galactic pole, J2000
double ngpRa, ngpDec;
northGalacticPoleJ2000(ngpRa, ngpDec);
const double ngpRaRad = Units::degreesToRadians(ngpRa * 15.0);
const double ngpDecRad = Units::degreesToRadians(ngpDec);
// Calculate galactic latitude for North Celestial pole, J2000
const double ncpLRad = Units::degreesToRadians(122.93192);
// Calculate galactic longitude in radians
double bRad = asin(sin(ngpDecRad)*sin(decRad)+cos(ngpDecRad)*cos(decRad)*cos(raRad - ngpRaRad));
// Find the two possible solutions for galactic longitude in radians
double rhs1 = cos(decRad)*sin(raRad-ngpRaRad)/cos(bRad);
double rhs2 = (-cos(decRad)*sin(ngpDecRad)*cos(raRad-ngpRaRad)+sin(decRad)*cos(ngpDecRad))/cos(bRad);
double l1 = ncpLRad - asin(rhs1);
double l2 = ncpLRad - acos(rhs2);
// Plug them back in and select solution which is valid for both equations
// (Error should be 0, but we have to allow for small numerical differences)
// There's probably a better way to solve this.
double l1lhs1 = sin(ncpLRad - l1);
double l1lhs2 = cos(ncpLRad - l1);
double l2lhs1 = sin(ncpLRad - l2);
double l2lhs2 = cos(ncpLRad - l2);
double l1Diff = abs(l1lhs1 - rhs1) + abs(l1lhs2 - rhs2);
double l2Diff = abs(l2lhs1 - rhs1) + abs(l2lhs2 - rhs2);
double lRad;
if (l1Diff < l2Diff)
lRad = l1;
else
lRad = l2;
// Convert to degrees in range -90,90 and 0,360
b = Units::radiansToDegrees(bRad);
l = Units::radiansToDegrees(lRad);
if (l < 0.0)
l += 360.0;
if (l > 360.0)
l -= 360.0;
}
// The following functions are from Starlink Positional Astronomy Library
// https://github.com/Starlink/pal