Astronomy Resources and Tutorials

How Bright is the Moon?

How bright is the Moon? That depends on a number of factors. The phase of the Moon is the primary one. Other obvious factors are the Earth-Moon and Sun-Moon distance as well as atmospheric transparency and extinction. Albedo and its variation is the final major factor affecting lunar brightness.


Temperature and Radiation

By: Mike Luciuk The three main methods of heat transfer resulting in change of temperature are conduction, convection and radiation. In conduction, energy is transferred by physical contact, like when one burns a finger while touching a hot pot. In convection, energy transfer occurs by fluid motion like water boiling in a kettle. In radiation, …


Astronomical Magnitudes

Several different types of “magnitude” are used in astronomy. Most commonly, apparent magnitudes are used to describe the brightness of stellar and solar system objects while absolute magnitudes are required to assess intrinsic brightness. A method is described to evaluate extended object versus sky brightness to calculate contrast, which explains why we can see Venus in daylight sky. There are specific procedures for calculating absolute magnitudes of asteroids, comets, and meteors. Factors such as color, albedo, and phase angles must, at times, be considered in their evaluation. The article will cover this topic with example calculations that can provide a firmer understanding of astronomical magnitudes.


Archived Tutorials

Astronomy Links