A star's magnitude is assosiated with its surface area/size. The reason Red giants may be brighter than those within the same colou (B-V), is simply due to the fact that it is much larger. (which results in an increased magnitude/brightness/luminosity.)
Because they have such a large surface area.
Red giants.
Yes red giants are the largest. But the bigger stars of red giants can be called red hyper giants.
red giants
Generally red giants are bigger, but really it has more to do with how hot they burn. Blue giants burn hotter and have more mass.
They are red giants.
Because they have such a large surface area.
Red giants.
In the usual position of the axes, the upper-right is populated by giants and supergiants.
The red giants like Betelgeuse and Antares are bright and - relatively - cool.
The red giants like Betelgeuse and Antares are bright and - relatively - cool.
The red giants like Betelgeuse and Antares are bright and - relatively - cool.
I'm going to have to go with red because in the question, it says "What color is a red giant?"Well its not always red, it might also be white or blue indicating that its bright and hot. But it is also red.
haemoglobin is blue in colour
To be bright you need to be hot, close or have a large surface area. The brightest coolest stars are red super giants. They have such a large surface area, that even though their surface temperature is cool - in star terms - their large surface area makes them appear bright.
Yes red giants are the largest. But the bigger stars of red giants can be called red hyper giants.
red giants