OBAFGKM
The Sun is a as a G2V type star, a yellow dwarf and a main sequence star. Stars are classified by their spectra(the elements that they absorb) and their temperature. There are seven main types of stars. In order of decreasing temperature, O, B, A, F, G, K, and M
Main-sequence,red giant,white dwarf.
The three main isotopes, in decreasing order of abundance, as 40Ar, 36Ar and 38 Ar.
That's the sequence of the colors of light in order from longest to shortest wavelengths.
O. This is the class of the blue/white giants.
The Sun is a as a G2V type star, a yellow dwarf and a main sequence star. Stars are classified by their spectra(the elements that they absorb) and their temperature. There are seven main types of stars. In order of decreasing temperature, O, B, A, F, G, K, and M
Spectral class is the categorization of stars by temperature and size, mostly the former. Spectral class B is very hot. In descending order (hottest to coolest) the spectral classes are O,B,A,F,G,K,M. You can see that B is very near the top.
If the temperature of the gas is decreasing, then in order to maintain constant pressure, you would have to compress it in volume.
The HR diagram has the star's temperature along the horizontal axis and the absolute magnitude (brightness) along the vertical axis. Each star is represented by a single dot. Higher temperature is usually associated with more brightness so many stars lie on or near a line on the diagram called the Main Sequence. Red giant stars are found on the upper right hand quarter because they are relatively cool but still very bright.
The order of the instructions is the sequence.
the denotation of sequence is put in order
ORDER BY
The reason main sequence has a limit at the lower end is because of temperature and pressure. The lower limit exists in order to exclude stellar objects that are not able to sustain hydrogen fusion.
Sequence of Events.
v
logical sequence
the rule defines whether we have to arrange in ascending order or the decreasing order as per demand