L7 telescopes

refraction

bending of light when it passes between substances, based on refractive indices of the two different media

refracting telescope

lens can bend parallel light rays to converge to a focus, but lenses must be large and heavy

reflecting telescope

can have a much greater diameter, focuses light with mirrors

light collected with a curved primary mirror that reflects light up to a secondary mirror

eye has 3 color receptors, _, peaking in the _

blue, green and red; green

broadband or narrowband filters

placed on telescope to only let certain range of color or specific colors through, then combined after to form a full color image

time monitoring

progression of events on human timescales can be observed, like supernovae

type 1 supernovae

binary star system, white dwarf accretes material from other star, eventually reaching critical density and exploding, possibly emitting beams of gamma radiation

type 2 supernovae

end of star’s life, core collapses in on itself, rebounds and releases gas to form a nebula; neutron star or black hole left behind

telescope properties

wavelengths that can be collected, light-collecting area (surface area = good), angular resolution (larger distances can take greater detail images)

light collecting area equation

A = π(d/2)²

ways to increase collecting area

build array of many telescopes and connect digitally e.g. CHIME

CHIME’s large field of view helps it monitor

fast transients e.g. radio bursts

limit to resolution comes from

interference of light waves within a telescope; less in a larger telescope

angular resolution equation

θ=1.22λ/D

interferometry

linking multiple telescopes so they have the angular resolution of a single large one

adaptive optics

deforming mirror to compensate for aberration’s in light’s path, i.e. atmospheric turbulence