Astronomy for Beginners

Here’s where you’ll find observing guides, how-to articles and great astronomy hints and tips. Don’t forget to also check out our comprehensive astronomy dictionary.

Astronomy Dictionary

An optical effect whereby the corners or edges of a telescope’s field of view are darkened. There are several ways vignetting can appear, but it can be reduced by taking flat fields (using software to remove its appearance) and in some cases by stopping down an aperture.

Yarkovsky effect

This is an effect that can change the movement or rotation of tiny rocky particles and small asteroids in space, caused by the absorption and reemission of photons of light. The result is that asteroids can be slightly perturbed in their orbits by this effect.

Absolute zero

This is the coldest temperature theoretically possible (-273.15 degrees Celsius), where the motion of atoms in a material would stop completely, leaving them only with a small amount of quantum mechanically energy.

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