The sun is a ....

Someone described the sun as a yellow dwarf. I don't think this is
correct. What is the correct description?

TIA

Lawrence

"Lawrence" lawrence@astronomer wrote in message
s.com...
Someone described the sun as a yellow dwarf. I don't think this is
correct. What is the correct description?

TIA

Lawrence


Actually, it is correct. The Sun is a main sequence star, and main sequence
stars are termed "dwarfs" (or dwarves"). Stars of the same exact spectral
class as the Sun look pale yellow through a telescope (Capella is similar
enough to show this) provided the star is bright enough to use the colour
receptors in the human eye. It is hard to gain an easy appreciation of the
Sun's colour as yellow simply because it is so bright as to overwhelm the
eye, saturating and bleaching out the colour receptors. White light is a
combination of sunlight and the light of the much bluer sky, which is
scattered sunlight. A star seen through a telescope is much less bright.

To gain an idea of how strongly circumstances govern our perception of
colour of the source of illumination, look around yourself at night in a
room lit by incandescent lamps. It seems pretty white. Then switch on the
same lamps during daylight (or even better, outdoors) and look at their
colour, which will seem a yellow-orange caste.

--
Mike Dworetsky

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"Lawrence" lawrence@astronomer wrote in message
s.com...
Someone described the sun as a yellow dwarf. I don't think this is
correct. What is the correct description?

TIA

Lawrence


Actually, it is correct. The Sun is a main sequence star, and main sequence
stars are termed "dwarfs" (or dwarves"). Stars of the same exact spectral
class as the Sun look pale yellow through a telescope (Capella is similar
enough to show this) provided the star is bright enough to use the colour
receptors in the human eye. It is hard to gain an easy appreciation of the
Sun's colour as yellow simply because it is so bright as to overwhelm the
eye, saturating and bleaching out the colour receptors. White light is a
combination of sunlight and the light of the much bluer sky, which is
scattered sunlight. A star seen through a telescope is much less bright.

To gain an idea of how strongly circumstances govern our perception of
colour of the source of illumination, look around yourself at night in a
room lit by incandescent lamps. It seems pretty white. Then switch on the
same lamps during daylight (or even better, outdoors) and look at their
colour, which will seem a yellow-orange caste.

--
Mike Dworetsky

(Remove "pants" spamblock to send e-mail)

"Lawrence" lawrence@astronomer wrote in message
s.com...
Someone described the sun as a yellow dwarf. I don't think this is
correct. What is the correct description?

Looking up "Hertzsprung Russell" on google should give you plenty of
information.

Marcus

"Lawrence" lawrence@astronomer wrote in message
s.com...
Someone described the sun as a yellow dwarf. I don't think this is
correct. What is the correct description?

Looking up "Hertzsprung Russell" on google should give you plenty of
information.

Marcus