the classification of a star according to its temperature as measured from the strengths of its spectral lines. In order of temperatures from hottest to coolest the spectral types are O B A F G K M. This is also the order of luminosity and mass (most luminous and most massive to dimmest and least massive).
The spectral type is the classification of a star according to its temperature as measured from the strengths of its spectral lines. This is also the order of luminosity and mass (most luminous and most massive to dimmest and least massive). In order of temperatures from hottest to coolest the spectral types are O, B, A, F, G
A system of stellar classification based on a star's surface temperature, color and size. The familiar spectral classes of O, B, A, F, G, K, M have been expanded to include L & T. These designate surface temperature (in kelvin) and thus the color. These are each sub-divided into 10 classes (0 - 9) from hottest to coldest. To both of these an additional term is added called the Luminosity Class ( Roman numerals I thru VII ) to designate the the size (based on the star's actual spectra) from largest to smallest. The Sun is classified as a G2 V type star. To better understand the Spectral Type designations you can visit the following website http://www.answers.com/topic/stellar-classification .
A classification assigned to a star according to the appearance of its spectrum. The spectral type is based primaly on a temperature sequence; a luminosity class may also be specified. Additional information about star's spectrum, such as the appearance of emission lines or unusually strong metal lines, may also be indicated. The classes originally designated A-Q, were subsequently rationalized and re-ordered as a temperature sequence, resulting in the final basic types still used : O, B, A, F, G, K, M. --- Spectral Type-- O5 B0 B5 A0 A5 F0 F5 G0 G5 K0 K5 M0 M5-- Temperature 35 000 K 21 000 K 13 500 K 9 700 K 8 100 K 7 200 K 6 500 K 6 000 K 5 400 K 4 700 K 4 000 K 3 500 K 2 600 K
A letter (O,B,A,F,G,K,M) that is characteristic of a star's colour. O stars are blue, then through white, yellow and orange to M stars which are red.
the designation of a star based on its spectrum, which is determined by its surface temperature
The spectral type of stars is a system of classification of stars based on the stars' spectra, emission lines that correlate with each star's surface temperature (and color). There are seven major spectral types. Stars range from blue and hot to red and cool. The spectral types are: O, B, A, F, G, K, and M (from hottest to coolest). Each of these letters is divided into 10 numerical classes, from hotter to cooler: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. For example, our Sun has the spectral type G2.
stars are divided into several spectral types according to the lines of the spectrum that they emit; from these lines, information on its temperature, on the pressure at the surface of the star, as well as on its chemical composition can be obtained. To each spectral type corresponds a certain surface temperature interval.
