assignment week 12 space mech
DESCRIPTION
A solution to determine the location of satelliteTRANSCRIPT
clear all; clcr_e=6371*1000; AU=149597871*1000; %mr1_ijk=1000*[0; -4464.696; -5102.507]; %mr2_ijk=1000*[0; 5740.323; 3189.068]; %mhour=12; minute=00; second=00; day=15; month=2; year=1995;
theta=acosd((dot(r1_ijk,r2_ijk))/((norm(r1_ijk))*(norm(r2_ijk))));theta1=acosd(r_e/norm(r1_ijk));theta2=acosd((r_e/norm(r2_ijk))); % Checking Line of Sight for two satellites if (theta1+theta2)>theta disp '1. Satellites are in LOS'else disp '1. Satellites are not in LOS'end
JD_0=367*year-floor((year+floor((month+9)/12))*7/4)+floor(275*month/9)... +day+1721013.5 ; T_UT1=(JD_0-2451545)/36525;T_TDB=T_UT1;M_s=357.5277233 + 35999.05034*T_TDB;lambda_M_s=280.4606184 + 36000.77005361*T_TDB;
%CONVERTING lambda_M_m WITHIN (+/-)0-360 deg-------------------------------while abs(lambda_M_s)>360 if lambda_M_s>0 lambda_M_s=lambda_M_s-360; elseif lambda_M_s<0 lambda_M_s=lambda_M_s+360; endend%CONVERTING M_m WITHIN (+/-)0-360 deg--------------------------------------while abs(M_s)>360 if M_s>0 M_s=M_s-360; elseif M_s<0 M_s=M_s+360; endend%--------------------------------------------------------------------------lambda_ecliptic=lambda_M_s+1.914666471*sind(M_s)+0.019994643*sind(2*M_s);r_s=1.000140612-0.016708617*cosd(M_s)-0.000139589*cosd(2*M_s);e=23.439291-0.0130042*T_TDB;r_ss=AU*[r_s*cosd(lambda_ecliptic); r_s*cosd(e)*sind(lambda_ecliptic);... r_s*sind(e)*sind(lambda_ecliptic)]; theta_s=acosd((r_e/norm(r_ss)));theta_ss=acosd((dot(r1_ijk,r_ss))/((norm(r1_ijk))*(norm(r_ss)))); % Checking Line of Sight for Satellite 1 and Sunif (theta1+theta_s)> theta_ss disp '2. Satellite 1 is in sun phase.'else disp '2. Satellite 1 is in eclipse phase.'end
EAS 3801 SPACE MECHANIC ASSIGNMENT WEEK 12LECTURER : DR. SYARIL AZRAD MD. ALINAME : ONG THIAM CHUNNO. MATRIC : 158347
Result:
1. Satellites are not in LOS.2. Satellite 1 is in sun phase.