![]() The albedo reported for an astronomical body may vary widely by the spectral and angular distribution of the incident radiation, by the "layer" of the body being measured (e.g. It is a dimensionless quantity typically measured on a scale from 0 (indicating total absorption of all incident radiation, as by a black body) to 1 (indicating total reflection). albedo A measure of the proportion of the total solar radiation received by an astronomical body, such as a planet, that is diffusely reflected away from the body. A galaxy hosting an AGN is called an active galaxy. active galactic nucleus (AGN) A compact region in the center of a galaxy displaying a much higher than normal luminosity over some part of the electromagnetic spectrum with characteristics indicating that the luminosity is not produced by stars. The material is acquired from a source external to the central object, and friction causes it to spiral inward towards the object. accretion disk A roughly circular mass of diffuse material in orbit around a central object, such as a star or black hole. ![]() It is defined as the apparent magnitude the star would show if it were located at a distance of 10 parsecs, or 32.6 light-years. A B C D E F G H I J K L M N O P Q R S T U V W X Y ZĪ A-type star absolute magnitude A measure of a star's absolute brightness.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |