You can probably guess that the Sun is very massive, compared with
the Earth. It is so massive, in fact, that directly comparing an Earth-like
object against the Sun quickly makes one's mind become dizzy!
Instead, let us imagine that the Sun is on the scale of the largest
land mammals on the Earth: the African elephants. When baby African
elephants are born they weigh a a few hundred pounds and grow to
a weight of several thousand pounds.
For this exercise, assume that our African elephant weighs 3300 pounds
or 1500 kilograms. What object compares to our African
elephant with the same proportion that the Earth and the
Sun compare with each other?
Are you having a hard time imagining it? Let us say that the
objects whose masses that we want to compare to our African elephant are: a Spider
Monkey, a Tabby Cat, a Wood Frog Tadpole, and
a Hamster. Take a look at the images below.
How Hot ?
How hot do you think the Sun is, compared with the temperatures of
familiar things on Earth?
You can probably guess that the Sun is very hot, compared with
familiar things on the Earth. We will use the same technique that we used
for the mass comparisons (above), because directly comparing temperatures of
what we are familiar with on the Earth, to the temperatures of the
Sun, will quickly make one's mind become dizzy!
When we ask how hot is the Sun we have to specify which part of the
Sun, because the Sun's temperature is different in different places.
Let us start with the Sun's photosphere.
Photospheric Temperature of the Sun.
The photosphere is the layer located closest to the Sun's surface, and
when viewed in
white light, such as the picture shown on the right,
the photosphere corresponds to the solar surface.
Each square centimeter of the solar surface emits as much light as a
6000 Watt lamp. The temperature of the photosphere is about 5800 K. How hot is
5800 degrees Kelvin? Water boils at about 373 degrees Kelvin,
therefore, the surface of the Sun is about sixteen times hotter than
boiling water. Can you imagine sixteen times? Try the following
comparison.
Imagine that the Sun's photospheric temperature is on the same scale
as the mass of a normal-sized human male, say about 180 pounds (82
kilograms). What object is one-sixteenth the mass of our man?
Are you having a hard time imagining it? Let us say that the
object whose mass that we want to compare to our Man is:
a Cat, a Baseball, and
a Pencil. Take a look at the images below.
The proportion of the mass of one these objects compared to the mass
of our man is the same one-sixteenth proportion that the temperature
of water boiling is to the temperature of the Sun's photosphere.
How Far is the Sun?
Coming Soon.
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We present here a summary of some of the Sun's
vital statistics with a "down-to-Earth" perspective.
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Image Credits
