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On Satellites in General
Observing the Satellites
15 other sections not shown
Altazimuth mounting altitude angle apogee apparent field astronomical atmosphere axis ball binoculars bright camera chart clock cosmic particles degrees device diameter direction distance double tick earth ellipse equator exit pupil exposure eye relief eyepiece field of view film focal length focus glass gravitational h m h m h m height horizon inches instrument International Geophysical ionosphere latitude launching light located longitude look magnetic field magnification magnitude mast measure meridian meteorites Millbrook School Photo moon Moonwatch teams Moonwatch telescope motion mounting moving objective lens observer optical bench orbit passage path perigee period photograph Phototrack plane position produce radiation rays right ascension rocket satel satellite satellite finder satellite passes satellite trace satellite watching satellite's School Photo Service semimajor axis Smithsonian Astrophysical Observatory space speed Sputnik star station surface telescope temperature tion track transmission transmitter tripod tube twilight velocity watchers