Class O stars are the hottest of stars with temperatures greater than 30,000oK
Small hot stars are classified as type O, B, or A stars based on their spectral characteristics. These stars are typically blue-white in color and have high surface temperatures and luminosities. They are also referred to as main sequence stars because they are actively fusing hydrogen into helium in their cores.
Hot stars are typically blue or white in color. These stars have higher surface temperatures, often exceeding 10,000 degrees Celsius (18,000 degrees Fahrenheit). Their intense heat results in the emission of light at shorter wavelengths, which gives them their blue or white appearance. Examples of hot stars include O-type and B-type stars in the stellar classification system.
O. This is the class of the blue/white giants.
T Tauri stars are pre-Main Sequence stars which are large but not as hot as O and B Main Sequence stars. They mainly fall in the categories of F, G, K or M, and they are not yet on the Main Sequence because they are still accreting mass and are still very young and unstable.
The seven types of main sequence stars in the universe are O (blue and hot), B (white-blue and hot), A (white and hot), F (yellow-white and medium), G (yellow and medium), K (orange and cool), and M (red and cool).
All stars are hot. Blue stars are the hottest.
hot, bright stars
Very hot stars typically appear blue or blue-white in color. These stars have surface temperatures exceeding 10,000 Kelvin, which emits most of their light in the blue and ultraviolet part of the spectrum. The extreme heat causes them to radiate energy more efficiently at shorter wavelengths, resulting in their characteristic blue hue. Examples of such stars include O-type and B-type stars.
Hot.
Hot.
hot,dim stars.
Red stars are cooler than stars of other colors but are still quite hot, which is why the glow red.