- With its mountains of ice, dunes of hydrocarbons, and methane/ethane seas, Saturn’s moon Titan is one of the most intriguing and alien worlds in our Solar System. But while some of its vistas may seem similar to those seen on Earth, standing on the surface of Titan would be a very unusual experience.
- Absolute magnitude (Wikipedia)
In astronomy, absolute magnitude (M) is a measure of the luminosity of a celestial object on an inverse logarithmic astronomical magnitude scale. An object’s absolute magnitude is defined to be equal to the apparent magnitude that the object would have if it were viewed from a distance of exactly 10 parsecs (32.6 light-years), without extinction (or dimming) of its light due to absorption by interstellar matter and cosmic dust. By hypothetically placing all objects at a standard reference distance from the observer, their luminosities can be directly compared among each other on a magnitude scale. For Solar System bodies that shine in reflected light, a different definition of absolute magnitude (H) is used, based on a standard reference distance of one astronomical unit.