They aren't. They often look that way because of the way various photographic emulsions and CCD arrays are sensitive to certain wavelengths of light.
A nebula is a region of interstellar gas and dust. Emission nebulae are clouds of ionized gas that allow red, blue, and violet light through. Generally, these nebulae appear reddish. Reflection nebulae are clouds of dust that simply reflect light from nearby stars. The dust particles of reflection nebulae usually only scatter blue light, so the appearance is blue. Other types of nebulae don't reflect light. Dark nebulae such as the Horsehead Nebula are so dense that they block light from other sources, such as background emission nebulae, reflection nebulae, or other stars.
A nebula is a region of interstellar gas and dust. Dark nebulae such as the Horsehead Nebula are so dense that they block light from other sources, such as background emission nebulae, reflection nebulae, or other stars. Other types of nebulae do reflect light. Emission nebulae are clouds of ionized gas that allow red, blue, and violet light through. Generally, these nebulae appear reddish. Reflection nebulae are clouds of dust that simply reflect light from nearby stars. The dust particles of reflection nebulae usually only scatter blue light, so the appearance is blue.
The color of emission nebulae is a result of the predominate gas or gasses in that nebulae. Different gasses glow in different colors. Blue, as the color of the star, indicates how hot the star is.
Emission nebulae can emit photons of many wavelengths, but the predominant color is red. They can also emit blue and pink colors (which are also part of the Balmer series of the hydrogen atom).
Nebulae (gas and dust) protostar (formed by immense pressure in nebulae) ^ becomes either a Brown dwarf (basicall dead :P) or a Main sequence star which becomes: A Red giant (when MSS runs out f hydrogen ) if red giant is small it becomes a white dwarf and does nothing or a planetary nebulae if it's a big one it either becomes a Neutron star or a Black hole
A nebula is a region of interstellar gas and dust. Emission nebulae are clouds of ionized gas that allow red, blue, and violet light through. Generally, these nebulae appear reddish. Reflection nebulae are clouds of dust that simply reflect light from nearby stars. The dust particles of reflection nebulae usually only scatter blue light, so the appearance is blue. Other types of nebulae don't reflect light. Dark nebulae such as the Horsehead Nebula are so dense that they block light from other sources, such as background emission nebulae, reflection nebulae, or other stars.
A nebula is a region of interstellar gas and dust. Dark nebulae such as the Horsehead Nebula are so dense that they block light from other sources, such as background emission nebulae, reflection nebulae, or other stars. Other types of nebulae do reflect light. Emission nebulae are clouds of ionized gas that allow red, blue, and violet light through. Generally, these nebulae appear reddish. Reflection nebulae are clouds of dust that simply reflect light from nearby stars. The dust particles of reflection nebulae usually only scatter blue light, so the appearance is blue.
The color of emission nebulae is a result of the predominate gas or gasses in that nebulae. Different gasses glow in different colors. Blue, as the color of the star, indicates how hot the star is.
Emission nebulae can emit photons of many wavelengths, but the predominant color is red. They can also emit blue and pink colors (which are also part of the Balmer series of the hydrogen atom).
Red, blue, green, and violet are found in the emission spectrum of hydrogen.
hydrogen
You get a dim grey. This is a result of all the minor frequencies of blue light that the red solid does have some reflection to .
Black because if a red light reflects off the blue surface there is no reflection, so the surface looks black.
The main reason is the ocean (and lakes and rivers), the reflection of the sky(blue color) gives it that extraordinary blue. For ex: if they sky was red, the water would also be red.
Well you see color is just the rays from the sun reflecting a certain color and if its blue then its reflecting blue. but heres the tricky part since its just a reflection blue paint and red paint smell the same so the answer is blue paint.
Black because if a red light reflects off the blue surface there is no reflection, so the surface looks black.
Blue photons are higher-energy than red photons. The equations governing the emission of light based solely on temperature state that an object giving off primarily blue light is hotter than one giving off primarily red light.