1. Celestial object identification: sunspots, comets, open clusters, planetary nebulae, ringed planets like Saturn, crater sketching from binocular view

2. Planetary comparison and stellar evolution: smallest planet (Mercury), hottest (Venus), first discovered by telescope (Uranus), Jovian moons (Jupiter), life cycles for solar-mass vs. high-mass stars (main sequence to white dwarf or supernova)

3. Telescope function and usage: Newtonian reflector structure, role of aperture and focal length in image clarity and brightness, suitable eyepiece focal length for high magnification of Jupiter

4. Venus observations and heliocentrism: phase change as proof of orbiting Sun, angular resolution vs. Venus’s apparent size, safe solar viewing during Venus transit, triangulation for Earth-Sun distance

5. Redshift and Hubble’s discovery: wavelength stretching indicates expansion, limitations of earlier telescopes (small aperture, low magnification), explanation of blue-shift for Andromeda, light pollution effects on modern observatories

6. Radio astronomy: metal dish necessity, resolution increase via larger or multiple dishes, reason for 21 cm wavelength use, radio interferometry advantages for improving resolution

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