Explain why the current spectral classification letters are all jumbled and not in alphabetical order

What will be an ideal response?


The spectral classification sequence originated with the amount of hydrogen in the star's spectrum and was labeled A through Q. However, after plotting that information, it was noticed that there was no pattern to the graph. When they used temperature instead of the hydrogen line, the graph made sense, and has been adopted since then.

Physics & Space Science

You might also like to view...

Classify the following statement as a characteristic

(a) of electric forces only, (b) of magnetic forces only, (c) of both electric and magnetic forces, or (d) of neither electric nor magnetic forces. The force exerted on a charged object cannot alter the object’s speed.

1.electric forces 2.magnetic forces 3.both electric and magnetic forces 4.neither electric nor magnetic forces

Physics & Space Science

Which domain or domains are made up of organisms without nuclei?

a. archaea only b. bacteria only c. eukarya d. both archaea and bacteria e. both bacteria and eukarya

Physics & Space Science

One way to ensure your navigation system is user-based is to perform usability tests.

Answer the following statement true (T) or false (F)

Physics & Space Science

Three flat layers of transparent material are stacked upon one another. The top layer has index of refraction n1, the middle has n2 and the bottom one has n3 . If n1 > n2 > n3, and if a ray of light strikes the top layer at an angle of incidence ?i = 30º, in which layer is the angle of refraction the greatest?

a. the top layer b. the middle layer c. the bottom layer d. Once the ray enters the touching layers, the angle of refraction remains constant.

Physics & Space Science