lew@ihuxr.UUCP (Lew Mammel, Jr.) (12/05/84)
I recently wrote a program to calculate the apparent relative brightness of Venus as a function of the angle, E-S-V, which varies approximately linearly with time. The program also prints the angle V-E-S, which is the "elongation" of Venus from the Sun in the sky. I assumed uniform surface brightness and circular orbits with Rv/Re = .723 The maximum elongation is 46.3, so we see that maximum brightness occurs significantly after this. By the way, when is maximum westward elongation this time around? I'm hoping someone else might want to join the fun and verify these results. Maybe someone has a table or something which gives more precise values. Anyway, here are my results. I'll post my formulas later. E-S-V V-E-S brightness (degrees) (degrees) (arbs) 180.000000 0.000000 0.673689 175.000000 2.097836 0.674507 170.000000 4.194176 0.676971 165.000000 6.287501 0.681106 160.000000 8.376248 0.686960 155.000000 10.458786 0.694597 150.000000 12.533386 0.704105 145.000000 14.598197 0.715593 140.000000 16.651209 0.729200 135.000000 18.690213 0.745091 130.000000 20.712757 0.763469 125.000000 22.716091 0.784574 120.000000 24.697094 0.808694 115.000000 26.652196 0.836175 110.000000 28.577273 0.867425 105.000000 30.467512 0.902936 100.000000 32.317248 0.943293 95.000000 34.119748 0.989196 90.000000 35.866929 1.041488 85.000000 37.548994 1.101180 80.000000 39.153934 1.169486 75.000000 40.666867 1.247860 70.000000 42.069124 1.338035 65.000000 43.336981 1.442049 60.000000 44.439869 1.562234 55.000000 45.337805 1.701122 50.000000 45.977649 1.861147 45.000000 46.287586 2.043909 40.000000 46.168893 2.248481 35.000000 45.483650 2.467724 30.000000 44.036780 2.680580 25.000000 41.551540 2.837198 20.000000 37.643009 2.835340 15.000000 31.814289 2.505032 10.000000 23.554963 1.688441 5.000000 12.693946 0.575283 0.000000 0.000000 0.000000 Lew Mammel, Jr. ihnp4!ihuxr!lew