A little about the Martian Atmosphere.

It's thin.

It does not have Raleigh Scattering, which produces the blue color to our atmosphere.

It has a relatively low-suspension of Dust in it. This gives it a slight red color.

There is enough atmosphere to scatter light, making it white, which consequently gives the reddish dust a "pink hue" when combined in the atmosphere.

A true color Mars pic will be this, bright surface reflecting an orangish dust and the exposed rock I'd describe as a "steel gray but non-metallic luster" and the sky would be whiter towards the zenith and a faint pink "haze" toward the horizon.

Recently disturbed soil might seem a "steel blue with a non-metallic luster."

I would give you examples of some true color pictures but I first need to find out how I can upload my pictures onto the internet or this site to link them to you.

They are all pretty big, good quality bitmaps. My favorite example is 3 mb so you know.

Anyway, it's useful for you all to know this, right now there's a debate thread of what the color of the Martian sky is. There's really no debate, we know what it is, NASA wants you to see it as more "alien" more...Orange or butterscotch.

Others want you to see it as more eartly, more Blue.

But the above is the reality. And that thread got bogged down in how things work, and no one there seems to realize that NASA's raw images are probably mislabled, explaining why some true color images are coming out horribly wrong.

But that's discussed there. This is just a thread to go to and read the facts.

Mars is losing atmosphere at a rate of about 2.2 pounds(1 kilogram)/second.


Diagram shows the solar wind creating a teardrop-shaped planetary tail behind Mars. Water and other volatile substances are lost to space in the process.

Click here for the story. There are other related links on this site.

Originally posted by AmerKiller
It does not have Raleigh Scattering, which produces the blue color to our atmosphere.

It does, CO2 contributes to Raleigh scattering. Its just the dust in the air overpowers the raleigh. There is a blue area surrounding the sun when viewed from the martian surface, also noticeable at sunrise/sunset.

Originally posted by AmerKiller
It's thin.

It does not have Raleigh Scattering, which produces the blue color to our atmosphere.

...

There is enough atmosphere to scatter light, making it white, which consequently gives the reddish dust a "pink hue" when combined in the atmosphere.

Just to point out: These are conflicting statements.

Raleigh scattering doesn't make a sky blue. It just makes our sky blue. Given a different atmospheric composition, our sky would be a different colour. It would still be Raleigh scattering causing that colouring, though.

And I believe the colour of the clear Martian sky is thought to be purple.

Ugh, I've bothered NOT to correct Kano here, but now with UT, I can not resist. Raleigh scattering is "back scattering" and is completely different from the effect of the Martian Atmosphere. Earth does this, the Martian atmosphere, eh, it's so negligible it has no effect at all to anything. The Earth's atmosphere acts as an "absorber" while the Martian atmospher acts as a prism.

That's the easy way to sum it up.

The Martian sky is white with a rose touch to it.

Pardon my stupidity, but how come what Intelearthling said about Mars isn't happening to Earth. Earth is closer to the sun afterall. Or is it happening to us and it's yet another thing I didn't know?

I believe it is because Mars does not have a magnetic field, so the solar winds blow the atmosphere away.

Unless I'm wrong, Mars has a magnetic field. It is a lot weaker than earth's but there is a magnetic field. There is some gravity on Mars, so there is a magnetic field...

Without any magnetic field, there is no gravity, and I believe that any object orbiting in space has a magnetic field, thus some gravity, even very weak.

I'm not too sure about this next one, but I think that in fact any object in space has some magnetic field and gravity, even loose objects.

All planets and moons have gravity, not all have magnetic fields. Having a magnetic field is not a prerequisite for having gravity.

Originally posted by SpookyVince
Unless I'm wrong, Mars has a magnetic field. It is a lot weaker than earth's but there is a magnetic field. There is some gravity on Mars, so there is a magnetic field...

Without any magnetic field, there is no gravity, and I believe that any object orbiting in space has a magnetic field, thus some gravity, even very weak.

I'm not too sure about this next one, but I think that in fact any object in space has some magnetic field and gravity, even loose objects.

I'm not sure where you're coming up with this, but you're completely wrong. Gravity is caused by mass. Magnetism is caused by moving electric charges. They're completely different and unrelated.

Ok ok, I messed it up a bit here... Gravity comes from mass, and electromagnetism comes from moving electrically charged particles... Agreed. But, again, if I'm wrong, I'd be happy to know, given a mass somewhere in space has some gravity (because of its mass, all right), it must have some form of electromagnetism, no? I mean, a magnet would work on earth the same way as it works on any other celestial body, wouldn't it??? Maybe I'm missing something if it's not the case...

Originally posted by SpookyVince...given a mass somewhere in space has some gravity (because of its mass, all right),

In the absence of any other mass, there is no force.

F = GMm/r^2 -- note that there are two m's, for two masses.

It does generate a gravitational field, though.

it must have some form of electromagnetism, no?

Only if it's a charged particle. Neutrons, for instance, are completely electrically neutral, and are not affected by EM forces.

I mean, a magnet would work on earth the same way as it works on any other celestial body, wouldn't it???

Yes, but the magnet isn't a magnet because it's on a body with a magnetic field. The magnet has its own magnetic field, caused by the movement of electrons in its atoms.


To the best of my knowledge, there are no massless, charged particles. There are chargless, massive particles (neutrons, neutrinos), and massless, chargless particles (photons).

Thanks Ut for your explanations, it seems I was a bit lost... Just one more precision then: a planet "lost" in space, not orbiting any star but just drifting in the void (I think we have identified one already, but I need to find a link for that...) would have also a gravity? And a EM field? In my views, its gravity would only be extremely low, and it should have anyway a EM field...

(I must admit that this is not my field of expertise, you have noticed probably! )

[Edit:]
Oh, and, I was "wrongly" talking about a mass... I meant a complex body, a planet, a star, a rock, anything like that, but not just one single particle. As such, any if these bodies is composed of electrically charged particles, right?

[edit on 4-10-2004 by SpookyVince]

Everything that has mass has gravity.

If you were floating in space, with, for example, a screwdriver near you, the fact that both objects have mass would make the two objects come together with a force that could be calculated with the formula given by Ut, F = GMm/r^2.

As the difference in mass between you and the screwdriver is great, the force would create an greater acceleration of the screwdriver towards you than the acceleration of your body towards the screwdriver.

Now, if the screwdriver was one of those that are magnetic, the screwdriver would have a magnetic field, but as the human body only has a very small magnetism, the effect of your body's magnetism would be very small when compared with that of the screwdriver.

I hope this helps, sometimes when I am trying to explain things I only confuse people even more.

SpookyVince...

Gravity and Electromagnetism are completely unrelated. You are relating them because you have to have a charged mass to have EM but the gravity of that mass is still unrelated.

All bodies have mass because they are made of matter. Only bodies with static magnetite or molten, spining, cores have EM fields.

For example...If earth's core stopped spinning, the moving charge would halt and Earth would have no magnetic field. The mass would stay the same, but the EM field would be completely gone.

all of these bold statements of knowledge!!

we know this and we know that,, it seems to be human nature to believe that we understand everything around us and are in control of our little world and what we can see in front of our face,,

alot of you making these BOLD "its because" statements need to realise that you are posing a theory, or a belief based on current beliefs on how science works and science is always changing and new rules are always popping up, the only true knowledge is knowing WE KNOW NOTHING,, thats it folks, and before u start STATING FACTS of how it is in the universe ask your self how we cant even agree on if we went to the moon, theres supposed to be a radiation belt that would cook us, science says so,,, but theres pictures and a mirror on the moon to calculate distance from earth,,how did it get there? lol we cant even explain why florida got slammed with so many storms that did hard right turns and u turns and even hurricane jeanne threw its force in reverse and backed up a few hundred miles and made our meteorologists look like idiots because it defied science,, science is theory only,,lets not be so pompious and act like we know,,or mabey we will upset the great god that makes THUNDER! BOOM BOOM,, lets sacrafice a virgin to make him happy,, that was a belief system too once used to explain what we didnt understand,,sorry im not trying to be obnoxious but come on lets keep an open mind

Its obvious we don't know all, far from it, but there are some things that we do know, or that we know to be a good approximation of the real way something works.

Of course we may try to explain some things, and if he had asked why the hurricanes did what they did, I would have said that I do not know, but as he was asking about things that are confirmed by practice and confirmed hundreds or thousands of times in more or less a century, I think that maybe we can have some confidence in what we say.

And you can be assured that I will not make sacrifices to any god because I do not believe in sacrificing other people for personal reasons and I do not believe in gods.

And yes, you are being a little obnoxious, maybe you are trying to be the next Charles Fort?

Originally posted by ArMaP
Its obvious we don't know all, far from it, but there are some things that we do know, or that we know to be a good approximation of the real way something works.

Of course we may try to explain some things, and if he had asked why the hurricanes did what they did, I would have said that I do not know, but as he was asking about things that are confirmed by practice and confirmed hundreds or thousands of times in more or less a century, I think that maybe we can have some confidence in what we say.

And you can be assured that I will not make sacrifices to any god because I do not believe in sacrificing other people for personal reasons and I do not believe in gods.

And yes, you are being a little obnoxious, maybe you are trying to be the next Charles Fort?

lol thats funny and i know i was being a little obnoxious but i was trying to make an example of how ridiculous it is to try to claim that we understand something thats so far away when we barely understand our own planet or even our own bodies,, mysteries and abnormalities are everywhere that defy our "knowledge" and while the example of being caught off gaurd by our abnormal weather defying science i have a better example,, at one time "SCIENCE" said we will never be able to launch a rocket into space,,why? because theres no oxygen,, they swore it would be impossible and people that thought it was possible didnt understand science and the way everything really works better then our scientists that were experts in that field,, science is like religion,, in the end its based on our current belief system and can be disproved on a daily basis once more "knowledge" becomes available

Gravity its not that far away.

There are many examples of cases of "impossibilities" in science, but that does not invalidate the fact that there are a lot of confirmed things.

Many people do not understand what I think is the true scientific spirit, if you not know anything about something, try to understand it. If there is not confirmation of some theory, then continue the search, but do not believe in everything just because someone says it is so.
That is the difference, in my view, between religion and science, but as I am not religious, maybe I am wrong about religion.

In that spirit, I ask you:
Why do you always put 2 commas instead of one in your posts?

i suppose the double comma is just my posting personality to show a pause or moment to make a point,, but in religion like science i tend to think its more we go with what we know to be self evident based on trial and error at that moment and some people hate the idea there may be more to it because they cant figure it out yet,, thats a whole insecurity issue i think,, but when we learn and grow like religion we tend to dismiss what we thought was fact or knowledge and pretend it didnt happen or we never really thought that if its too embarrasing