# Re: Carbon source + oxygen = CO2

On Sun, 26 Jun 2011 22:31:13 +0900, Arkalen <skizzir@xxxxxxxxx> wrote:

(2011/06/26 18:18), iaoua iaoua wrote:
<snip stuff addressed in other post>

Now we've got that out of the way we do agree that the gravitational
forces we are talking about in a developing solar system are so
massive that the Earth's atmosphere is a very weak comparison right?

On reflection I went and did the math, to see how far something (say a
gas molecule) would have to be from the Sun to feel the same
gravitational pull as air does on the surface of the Earth.

I got 3.7 x 10^6 km.

That's about fifty times closer to the Sun than the Earth is; it's over
ten times closer to the Sun than *Mercury* is. In fact, the Sun's
photosphere is less than six time closer to its center than this
molecule would be.

Even considering a molecule near the top of the thermosphere instead of
at the Earth's surface I get 4.1 x 10^6 km. Not much change there.

In other words, in today's Solar System where 98% of the mass of the
whole system is concentrated within the Sun's radius, every particle
that is further away from the Sun than 4 million kilometers feels less
gravitational force from this mass than the Earth's atmosphere does from
the Earth's mass. (Mercury is 58 million kilometers from the Sun).

When we consider the proto-Solar System gas cloud, which would have
pretty much the same mass but very much NOT concentrated within the
Sun's radius... Every particle in that cloud would have felt a force
many, many, many times smaller than particles feel up in the Earth's
thermosphere.

I wonder how much smaller. Let's consider a molecule at the outer edge
of the gas cloud, which would be feeling the mass of the whole cloud as
if it were concentrated in a point particle at the center. Because I
don't know how big this gas cloud was I'll be VERY conservative and say
it's at Neptune's orbit (in reality I imagine it would have stretched at
least to the Kuiper belt, probably even the Oort cloud or further) (this
is before the whole thing had collapsed significantly of course. For one
thing I'm assuming the cloud is spherical; the math might be different
for a disk).

The force a molecule at Neptune's orbit feels from the Sun (which is 98%
of the whole mass of the Solar System) is 8.25 x 10^-8 times the force
this molecule would feel up in the Earth's thermosphere.

That's almost a billion times smaller.

<snip stuff addressed in other post>

This is quite correct and the calculations aren't too complex. The
mass if the sun is 1/3 of a million times that of the earth.
Gravitational forces vary as the square of the distance and linearly
with the mass. If the distance from the sun is more than 600 times
the distance from the earth, the sun's gravitation will be weaker.
Objects in our atmosphere are about 4000 miles from the center of the
earth. Objects around the sun more than 4000 * 600 = 2.4 million
miles from the sun will feel a weaker gravitational force from the sun
than the same object near the surface of the earth. That is extremely
close to the sun.

iaoua's knowledge about gravity is quite comparable to his knowledge

.

## Relevant Pages

• Re: Friar Broccoli is under the delustion that our Solar System is isolated from the rest of the Uni
... Impossibility of the Earth being the barycenter of the universe ... solar system is such a "rotating system". ... the sun have "decided" that the sun is the center ... of mass of the system, and 5 or 6 others ...
(talk.origins)
• Re: Tonys heliocentrism is perversity-like
... >>>Our Sun is by far the largest mass in the Solar System. ... however, Newton's law of gravity doesn't ...
(talk.origins)
• Re: What if there was no dark matter?
... then I calculate that a sphere around the solar system that includes ... mass in dark matter than in ordinary matter. ... 0.001% of the mass of the earth as dark matter. ... sun and I assume that goes for other solar systems as well. ...
(talk.origins)
• Re: What if there was no dark matter?
... then I calculate that a sphere around the solar system that includes ... mass in dark matter than in ordinary matter. ... 0.001% of the mass of the earth as dark matter. ... sun and I assume that goes for other solar systems as well. ...
(talk.origins)
• Re: "Deep Impact" mission; designed to deceive?
... >> formed out of an interstellar cloud of gas and dust. ... >> Not so, says Dr. Oliver Manuel, professor of nuclear chemistry at UMR. ... >> "Comets travel in and out of the solar system, toward the sun and away ...
(sci.astro.amateur)