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Here is how I understand these terms.

  • Apparent magnitude is what you can see, or measure from where you really are and where the object really is.
  • Absolute magnitude is a mathematical prediction based on a standardized distance and configuration (see below) so that you don't have to specify the particular conditions. Venus always has roughly the same absolute magnitude because it's always roughly the same size and albedo (see next), but varies greatly in apparent magnitude be cause of changes in distance and phase angle (sun-venus-earth angle).
  • Albedo is a little tricky because different objects have different surface roughness and angular scattering properties. If it was a smooth ping-pong ball and had a well defined diffusivity profile, then it's easy to imagine a white, gray, or black ping-pong ball representing transitions from 1 to 0.

I've just asked Is albedo ever greater than unity? How is it calculated for various surface diffusivities and specular reflection? to get at some of those subtleties.

For stars and other objects that make their own light:

enter image description here

For planets, asteroids, comets, satellites (artificial and natural) and even electric cars 1, 2 that are seen in reflected light from the Sun:

enter image description here

Here is how I understand these terms.

  • Apparent magnitude is what you can see, or measure from where you really are and where the object really is.
  • Absolute magnitude is a mathematical prediction based on a standardized distance and configuration (see below) so that you don't have to specify the particular conditions. Venus always has roughly the same absolute magnitude because it's always roughly the same size and albedo (see next), but varies greatly in apparent magnitude be cause of changes in distance and phase angle (sun-venus-earth angle).
  • Albedo is a little tricky because different objects have different surface roughness and angular scattering properties. If it was a smooth ping-pong ball and had a well defined diffusivity profile, then it's easy to imagine a white, gray, or black ping-pong ball representing transitions from 1 to 0.

For stars and other objects that make their own light:

enter image description here

For planets, asteroids, comets, satellites (artificial and natural) and even electric cars 1, 2 that are seen in reflected light from the Sun:

enter image description here

Here is how I understand these terms.

  • Apparent magnitude is what you can see, or measure from where you really are and where the object really is.
  • Absolute magnitude is a mathematical prediction based on a standardized distance and configuration (see below) so that you don't have to specify the particular conditions. Venus always has roughly the same absolute magnitude because it's always roughly the same size and albedo (see next), but varies greatly in apparent magnitude be cause of changes in distance and phase angle (sun-venus-earth angle).
  • Albedo is a little tricky because different objects have different surface roughness and angular scattering properties. If it was a smooth ping-pong ball and had a well defined diffusivity profile, then it's easy to imagine a white, gray, or black ping-pong ball representing transitions from 1 to 0.

I've just asked Is albedo ever greater than unity? How is it calculated for various surface diffusivities and specular reflection? to get at some of those subtleties.

For stars and other objects that make their own light:

enter image description here

For planets, asteroids, comets, satellites (artificial and natural) and even electric cars 1, 2 that are seen in reflected light from the Sun:

enter image description here

1
source | link

Here is how I understand these terms.

  • Apparent magnitude is what you can see, or measure from where you really are and where the object really is.
  • Absolute magnitude is a mathematical prediction based on a standardized distance and configuration (see below) so that you don't have to specify the particular conditions. Venus always has roughly the same absolute magnitude because it's always roughly the same size and albedo (see next), but varies greatly in apparent magnitude be cause of changes in distance and phase angle (sun-venus-earth angle).
  • Albedo is a little tricky because different objects have different surface roughness and angular scattering properties. If it was a smooth ping-pong ball and had a well defined diffusivity profile, then it's easy to imagine a white, gray, or black ping-pong ball representing transitions from 1 to 0.

For stars and other objects that make their own light:

enter image description here

For planets, asteroids, comets, satellites (artificial and natural) and even electric cars 1, 2 that are seen in reflected light from the Sun:

enter image description here