NASA

Light Curves, Spectra and Images.
Observing the lights is mostly the only way we can learn about them. If you graph different energies you can make a spectrum.
Quiz: 100%
Try this: The CD reflects a rainbow

X-ray Bianary Stars:
They emit x-rays. Contain 2 stars that orbit around their common center of mass.
Quiz: 100%
In an eclipsing binary, the brightness of the smaller, brighter star is greatest when its companion star, in this case the dark colored ball, is behind it.

BLack Holes:
DIstant and harmless things. Black holes cosume gas and little stars.
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Spectral anylisis:
Display of elctromagnetic radiation. It was reintrodusedwhen newton decomposed the white sunlight into a spectrum of colors.
Quiz: 75%
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