Was the collision that formed Luna responsible for water and life on Earth?

[steve_bank]

From a quick search it looks like it is thought water already existed in the nebula to begin with. Learn something new everyday.


http://curious.astro.cornell.edu/ab...-water-in-the-universe-come-from-intermediate

No, H2O cannot exist in stars, but H and O separately can. Hydrogen is the basic building material of the universe, created in the Big Bang. Oxygen is created by nuclear reactions in stars. If you put H and O together in the cold of space, you get H2O. There are enormous amounts of water in space. In fact, nearly all of the oxygen in space is in the form of water or carbon monoxide. Similarly, most the carbon and nitrogen in space are also in their most hydrogenated forms: methane (CH4) and ammonia (NH3).

 

[bilby]

As I seen it regardless of form any mass has to overcomes gravity to leave the planet. When a comet hit the panet I'd think mot of the kinetic energy would end up as heat, not kinetic of motion in energy in water molecules.

Now I am wondering what you think heat actually is - if it's not the kinetic energy of molecules.

 

[bilby]

From a quick search it looks like it is thought water already existed in the nebula to begin with. Learn something new everyday.


http://curious.astro.cornell.edu/ab...-water-in-the-universe-come-from-intermediate

No, H2O cannot exist in stars, but H and O separately can. Hydrogen is the basic building material of the universe, created in the Big Bang. Oxygen is created by nuclear reactions in stars. If you put H and O together in the cold of space, you get H2O. There are enormous amounts of water in space. In fact, nearly all of the oxygen in space is in the form of water or carbon monoxide. Similarly, most the carbon and nitrogen in space are also in their most hydrogenated forms: methane (CH4) and ammonia (NH3).

I find it astonishing that you are learning this newly today, as I mentioned it in this very thread a fortnight ago.

 

[fromderinside]

From: The Vapors | Electrical Contractor Magazine https://www.ecmag.com/section/safety/vapors
Gasoline is probably the best known and most widely used of the flammable or combustible liquids. ... Gasoline is very volatile when changing from a liquid to a vapor at low temperatures. Gasoline vapors are denser than air, meaning these vapors will sink and collect at the lowest point.

According to Volatile fluids are in constant flux between gaseous and liquid states in containers and elsewhere in the world. As steve_bank says gas vapor loses kinetic energy it settles toward the liquid surface and eventually will become liquid while at higher temperatures, as pressure varies, liquid gasoline near the surface will exceed energy needed to break the cohesive energy state of surface gas and become a gas vapor. So on both counts gas being heavier than air and gas vapors becoming gas liquid a reading of steve_bank's post is correct

So overall Vapor will settle and become liquid and liquid will evaporate from the liquid surface sustaining a more or less constant pressure/temperature/volume balance in a gas tank.

Of course if all there is in a gas tank is gasoline vapor and air, kept as appropriately high temperature, as bilby argues, gas will remain gas vapor above it's vaporization temperature, but since gasoline is heavier than air it will sink to the bottom of the tank again in line with steve_bank's assertion and remain a gas as bilby argues.

IMHO they are shouting past each other based on different assumptions.

As for evidence of Origin of Water in the Inner Solar System http://astrobiology.com/2017/07/origin-of-water-in-the-inner-solar-system.htmlp

There is a long-standing debate regarding the origin of the terrestrial planets' water as well as the hydrated C-type asteroids. Here we show that the inner Solar System's water is a simple byproduct of the giant planets' formation.Giant planet cores accrete gas slowly until the conditions are met for a rapid phase of runaway growth. As a gas giant's mass rapidly increases, the orbits of nearby planetesimals are destabilized and gravitationally scattered in all directions. Under the action of aerodynamic gas drag, a fraction of scattered planetesimals are deposited onto stable orbits interior to Jupiter's. This process is effective in populating the outer main belt with C-type asteroids that originated from a broad (5-20 AU-wide) region of the disk.

As the disk starts to dissipate, scattered planetesimals reach sufficiently eccentric orbits to cross the terrestrial planet region and deliver water to the growing Earth. This mechanism does not depend strongly on the giant planets' orbital migration history and is generic: whenever a giant planet forms it invariably pollutes its inner planetary system with water-rich bodies.

and presented in NOVA presentations recently this year suggests rather than water coming from comets water on the inner planets is probably due to jupiter and the other gas planets knocking meteors out of orbit and into earth and the inner planets.

While it is true that the sun blasted a lot of water into constitutes H₂ and O and O<sub>2 and is still driving that matter outward there is evidence rocky planets retained water within supported by evidence there is still water on mars and the moon.

As for evolution I think bilby covered that pretty well. OK, OK. Brilliantly.</sub>

Gas isn't vapour. Vapour isn't gas.

Vapour is to gas, as emulsion is to solution.

A gas consists of free molecules moving independently and colliding individually with each other, and with the walls of its container.

A vapour consists of droplets of liquid, each containing huge numbers of molecules moving in concert through a gaseous substrate.

A "gas vapour" isn't anything at all, other than a confusion either between the completely different physical states "gas" and "vapour"; Or between "gas" the physical state, and "gas" the abbreviation for "gasoline" (gasoline is typically only considered in the liquid and vapour states; to render gasoline gaseous would require raising its temperature to about 126°C, or 258°F, and this isn't a common engineering scenario).

Either way, it's not a phrase that can possibly reduce confusion.

I think I covered the participants of gasoline in a tank which has air in it as well. I left uncertainty about the mechanism by which vapors (aggregates of molecules) and gaseous form would be reintroduced into the liquid state. Both are heavier than air and will descend below air for the most part over time. vapor overcomes adhesion at the surface through mutual attraction while gaseous first aggregates into droplets, vapor, before surface areas adhesive properties result in mutual attraction and reintegration as liquid.

 

[steve_bank]

PV=NRTZ where Z is an empirical compressibility factor.

Enough pressure and argon or nitrogen or oxygen liquefies. Liquid nitrogen and argon when used for cryogenic cooling acts just like evaporating water. Put a drop on a surface and it evaporates reducing temperature. It all depends on pressure and temperature and the material properties.

When compressed nitrogen gas is used to cool a sensor high pressure gas is vented on a surface of the sensor where it then condenses to liquid and evaporates back to gas in the atmosphere cooling the sensor. Joules-Thompson cooling cycle.

I believe I read we are losing water to space at the top of the atmosphere. Mars could not keep an atmosphere due to low gravity.

As to atmospheric water vapor escaping I imagine the law of partial pressures applies. There is a pressure differential between space and each component in the atmosphere, not necessarily the same. That pressure is offset by gravity.