What is the chance to find heavy metals (like uranium) resources outside the Earth?

Question

I mean places like the Moon, the Mars or maybe the Belt of Planetoids... or other places of our Sun System. In spite of oil, requiring biological material to become, heavy metals like uranium is “a death matery” presence (however it is a rare matery). Also the atomic plants are the more futurous and more efficient than power plants using oil and coal. When I noticed that despite of colonization of other planets is planed firstly to establish “space tourism” I was shocked. I always know that humans are short-sighted, but this. At least I consider what would be the wright reason of new genesis aiming at space, so the answer was the heavy metals resources. That is why I am asking if using curent astrological and space traveling technology we could find those “gold of new world” and maybe repeat the success of U.S.A. begining?

Answer 1

Probably not. But I'm sure there are metals out there that we don't have on earth, some of which could be even more effective at uses we use minerals for today.

Just curious, why did you pick uranium?

Answer 2

Check out Wikipedia.

Uranium is probably extremely rare if non-exsistant on the moon.
Actually water will be the most important part of space colonizing in addition to more common ore metals.

Uranium will probably be obsolete as a power source in the near future!

Answer 3

properly, i'm a Christian and that i like heavy metallic. fairly, it certainly relies upon on the way it impacts you, basically remember that some songs do say stuff like "Your God Is lifeless" or "Bow to devil, and start up a extra suitable existence". don't be naïve to the undeniable fact that those words are there and genuine. yet basically remember who your God and saviour is, Jesus Christ, and no-you will substitute that. If a song reasons you to stumble do not pay attention to it anymore. it fairly is going to be for the superb, yet ordinary, different than that, delight in the song, pay attention to three Christian metallic bands additionally and keepin headbangin' and don't ignore God! God Bless!

Answer 4

A lot of heavy metals are found in space rocks.

Answer 5

all material found in nature exist everywhere in the universe. there is noting special about the earth other than we are here.

Answer 6

Most of the heating in the Earth comes from decay of uranium. ...

The Planets

The Nine Planets

We have data on the various planets that allow us to compare them.

Comparison of Planets

We notice differences between what we call terrestrial planets and what we call jovian planets.

Differences between Terrestrial Planets and Jovian Planets

We will continue to study the goals:


How do other planets differ from ours?
Why they are different?
How they got that way.
How we study them?

We will be doing comparative planetology - comparing one planet with another. We will base the comparisons with Earth.

Three major areas we will look at are

The surface of the planet
The interior of the planet
The atmosphere of the planet

The terrestrial planets
--------------------------------------------------------------------------------
History of terrestrial planets
--------------------------------------------------------------------------------

The theory of the origin and formation of the solar system suggests that the earth and the other terrestrial planets passed through four stages in its formation and development. On the earth - we see evidence of the following four stages. To varying degrees, on the other terrestrial planets, we also see evidence of the four stages.


Differentiation
Differentiation is the separation of materials according to density. From knowing the mass and volume of the Earth, we can calculate its average density. The earth's average density is higher than the density of rocks that we find at the surface. Therefore, we know that the earth must be more dense further inside. The earth has a dense core and a low density crust. In its formation, the earth was in a molten state which allowed dense materials to sink to the center.
Cratering
When a solid surface formed on the earth, there was still a lot of debris that was orbiting around the sun. The collisions between the early earth and that debris caused cratering. We see that cratering on the Moon and on Mercury where the lack of an atmosphere prevented the erosion of the craters.
Flooding
The earth was flooded by lava and water. Decay of radioactive elements inside the earth heated the interior. Lava rose and covered the surface. As the atmosphere cooled, water fell as rain. Water flooded the surface, forming the first oceans.
Surface Erosion
Many processes can cause erosion of the surface of the Earth.

Earth

The interior of the earth is molten and generates a magnetic field. The earth's crust is active. The action of plate tectonics causes earthquakes, volcanoes, forms mountains. Over 75% of the surface of the earth is covered with water. The atmosphere of the earth is rich with oxygen.


Interior
From the theory of the formation of the solar system, we expect that the Earth is differentiated. But we also have evidence of this from observation.

From its mass and volume we estimate a density of 5.5 times that of water. Since rocks only have a density of about 3, we expect that there must be something pretty dense inside. The interior of the Earth must be made of material denser than rock.

From seismology (the study of earthquakes) we can determine that the center of the Earth is molten, since some seismic waves can penetrate a liquid and some cannot.

These two observations can be explained if the core of the earth is molten iron and nickel with a density of 14 times the density of water and a temperature of about 6000K (about as hot as the surface of the sun). The high pressure in the center keeps the inner core solid, surrounded by a liquid core.

The Earth has a magnetic field. This is further evidence that the center of the Earth is liquid iron. A conducting liquid undergoing rotation would generate a magnetic field. If the earth were totally solid, we would not observe a magnetic field.

Why do we have a molten core? The earth is kept hot by energy released by radioactivity in rocks. Most of the heating in the Earth comes from decay of uranium.

Above the liquid core is the largest part of the solid earth, called the mantle, a solid with the ability to flow. Above the mantle is the solid crust.


Surface
One of the most obvious features of the Earth is the fact that its surface is constantly changing and being eroded. Among the causes of erosion are:

Water: earth is the only planet with liquid water. The movement of water causes erosion and shaping of the rocky surface.
Atmospheric Erosion: winds, rain, snow, ice
Life (including us!)
Volcanoes: Molten rock rises to the surface. Some volcanic eruptions produce mountains, such as Mauna Kea, other eruptions spread out to form lava plains, such as the Snake River Basalts.
Plate tectonics: continents move around the surface. Solid plates of crust ride on a plastic (solid that is capable of flowing) mantle.

It is the collisions between continents that give rise to most of the worlds mountain ranges, earthquakes and volcanoes.

Rift Zones
Subduction Zones

Atmosphere
Earth's atmosphere is about 78% nitrogen (N2), 21% oxygen, (O2) 1% argon.
Tropical Storm

There are also rarer gases (less than 1% concentration) which are very important

Water vapor (H2O), which give us highly visible clouds
Carbon dioxide, (CO2)
Ozone (O3) which protects us from ultraviolet radiation from the Sun.
The Earth's atmosphere is quite different from the other planets.

Theory tells us that the early atmosphere of the earth was probably quite different from the present atmosphere. The early atmosphere may have contained much more carbon dioxide (as Venus's atmosphere still has). However, the oceans on the earth may have removed that carbon dioxide from the atmosphere by dissolving the carbon dioxide in the water. This is quite fortunate for us. Carbon dioxide in the atmosphere can trap heat, causing the greenhouse effect, where heat, from the sun, can reach the surface, but cannot escape out.

Greenhouse Effect

Venus demonstrates the greenhouse effect to an extreme, the surface of Venus is very hot, making Venus quite uninhabitable.

There is evidence that the greenhouse effect is increasing. Carbon Dioxide is released to the atmosphere through the burning of fossil fuels. There is also widespread destruction of tropical forests. These forests are important in extracting carbon dioxide from the atmosphere and replenishing the atmosphere with oxygen. So far in this century, the amount of carbon dioxide has increased by about 25 percent. If this trend continues then the carbon dioxide level in the atmosphere will double the value it was before the industrial revolution. What the consequences will be are not really known, but most scientists are convinced that global warming is indeed taking place due to the greenhouse effect.

CO2 levels

The ozone layer in the atmosphere protects the Earth from high energy photons. Recall - ultraviolet radiation is blocked by ozone in the atmosphere. Ultraviolet radiation can be very harmful. That is why there is concern about chloroflourocarbons (CFCs) which can destroy ozone when they leak into the atmosphere.


Cratering
On the moon, we see craters, evidence that interplanetary debris bombarded the moon. On Earth, however, we do not see much evidence of impact cratering. It is true that the Earth's atmosphere shields us from some impacts - small pieces of interplanetary debris burn up when they enter earth's atmosphere. But the atmosphere would not shield earth from impact of larger objects. It seems reasonable that in the past, the earth was as heavily cratered as the moon. But, unlike the moon, there are active geologic processes that renew the surface of the earth. Plate tectonics and volcanic activity shape and change the crust of the earth.
There is some evidence of impacts. In recent history, on June 30, 1908, near the Tunguska River in Siberia, an explosion took place in the atmosphere about 8 km above the surface. No craters were formed in this explosion, but the blast did flatten trees in the forest.

Meteor Crater, in Arizona, is a relatively intact crater that was formed from an impact about 50,000 years ago. Scientists have identified more than 150 other impact craters, although most of those are very eroded.
Moon

We include the Moon in this section, even though it is not another planet, because it is the only other world that humans have visited. In addition, study of the moon can give clues to the origin and development of the other planets.

The moon is small, only (1/4) one-fourth the diameter of the Earth. The mass of the moon is about 1/80 of the mass of the mass of the earth and 1/6 of the Earth's surface gravity. The Moon always keeps the same side toward the Earth. On the following photo of the moon, the left side shows part of the hemisphere that faces the Earth. The right side, the side that faces away from the earth, is dominated by highlands.


Atmosphere
The moon has no atmosphere. The reason is that the gravity of the moon is too low, about (1/6) one-sixth of that of the Earth. Since the gravity is so low, the escape velocity is also low. The escape velocity is the velocity needed to escape the force of gravity. A low escape velocity means that gas atoms and molecules can more easily escape the gravitational force of the moon. The moon could not hold on to an atmosphere.

Exploration of the Moon
In June 1969, the first astronauts landed on the moon. There were six Apollo missions that landed on the moon. The astronauts collected soil samples from the surface and mapped and photographed the lunar surface from orbit.

Surface
The visible surface of the moon is dominated by dark areas called maria (Latin for seas) and lighter areas which are heavily impacted by craters. The dark areas are the lowlands, a smoother surface composed of darker rocks. The lighter areas are the highlands, rougher and heavily cratered.

Highlands rock

The surface of the moon is dominated by craters, which are due to meteorite impacts in the past.

Moon craters

We see craters on Earth also. The Barringer Crater in Arizona is such a crater. We see many craters on the moon, but we don't see very many craters on the Earth. Moreover, we don't experience very many meteorite impacts in this present day.

It is believed that in the early solar system, there was much more debris in space, which collided with the newly formed planets, causing the cratering that we see both on the moon and on Mercury. The Earth would have undoubtedly experienced just as much cratering as the moon.

However, on the moon (and, as we shall see, on Mercury as well), there was much less erosion. The moon has no atmosphere to cause erosion. The moon has no water to cause erosion. So the evidence of early impacts and cratering is preserved on the moon. On the other hand, on Earth craters get eroded away quite quickly.

The surface of the moon has a dusty layer on top. This is believed to be caused by meteorite impacts which crushes the rock. Small meteorites (micro-meteorites) may still impact the moon, grinding the rock to a consistency of powder.

There are no signs of current volcanic activity, though the maria are believed to be ancient lava flows. That indicates that, unlike the Earth, the Moon does not have a molten core.


Impact Cratering
The types of craters that we see on the moon are different than the volcanic craters we see on earth. Craters on the moon are circular features, rimmed by mountains, with the interior floor usually below the level of the surrounding plains. Earth's volcanic craters are smaller and deeper and occur at the tops of volcanic mountains.

Differences between Craters

Impact craters are formed when a high velocity projectile hits the surface.

Formation of a Crater


The projectile impacts the surface.
Because of the high velocity, it explodes upon impact. A shock wave spreads out through the surrounding rock. This shock wave fractures the rock, and a crater is formed. The size of the crater is generally 10 to 15 times the diameter of the projectile.
Material is ejected from the interior of the crater. The rim of the crater is turned up by the force of the explosion. Sometimes the ejected material is thrown out with such velocity that it forms secondary craters where this material strikes the surface.
The ejected material settles back down, partially filling in the crater and sometime creating a central peak.


Interior
The Moon has a lower average density than the Earth (3.3 g/cm3 versus 5.5 g/cm3. The rocks that were brought back to earth by Apollo missions were close to the average density, which means that the Moon's interior is probably about the same density as the surface. Unlike the earth, the moon does not have a molten iron core.

Astronauts left a seismograph on the surface of the moon and, on purpose, crashed a lunar lander. The seismograph registered for about 45 minutes. This indicates that the moon doesn't have molten core - for otherwise it would not have resonated for so long.


Formation
We can examine the history of the moon in light of the four stages of terrestrial planet development. The size of the moon plays a big role in its history.



Differentiation
Analysis of moon rocks obtained during the Apollo space missions show that the moon is likely to be differentiated. The crust is low-density anorthosite, while the core is not large, contains little iron, but is denser than the surface.

Cratering
Cratering is quite obvious.


Flooding
Impact craters cracked the crust and led to the third stage of flooding - lava flooding. We see evidence of lava flooding in the maria regions. Even though as a relatively small object, the moon cooled rapidly after its formation, nonetheless, some processes, such as radioactive decay, could have heated the subsurface material, causing the lava flows whose evidence we see.


Surface Erosion
There is not much surface erosion that happened on the moon. The moon lacks an atmosphere and lacks water. Erosion, thus, is limited to bombardment of meteorites. As the moon cooled down, it lost its internal heat. With no molten interior, there is no volcanism to change the surface. The moon is geologically inactive. There is no plate tectonics.


Note: the moon is small. Since it is small, it cooled fairly rapidly after its formation. That is why it does not have a molten core. That is why there is no volcanism on the moon. Unlike the moon, the earth is larger, it hasn't entirely cooled off yet. It still has a very hot molten core. The small size of the moon meant that it could not hold on to an atmosphere. So the moon hasn't experienced the surface erosion that the earth has.


Origin
We are by no means certain how the moon formed, but the most likely scenario is that there was a collision between the Earth and another smaller planet (maybe one that was about the size of Mars), that threw stuff off into space. This could explain why the interiors of the Earth and Moon are so different.

Mercury

Mercury is intermediate in size between the Earth and the Moon. It is larger than the Moon, but less than half the diameter of the Earth. Because of its relatively small size, it too cooled off rather quickly. Like the moon, its appearance is heavily cratered.


Surface
Because it is so close to the sun, the surface temperature of Mercury can reach 800 degrees Fahrenheit. It has a slow rotation period (59 days), so there are extreme variations in its surface temperature (-280o F to 800o F ). In 1974-1975 Mariner 10 flew past Mercury. Photos from Mariner showed a heavily cratered surface.

Caloris Basin

Other analysis showed that large areas have been flooded by lava and then cratered. There are other indications that the planet may have shrunk as it cooled, causing the crust to buckle and form long scarps or cliffs. Some of these scarps, such as Discovery Scarp, cut across craters. This means that the scarps formed after cratering.

Discovery Scarp

Interior
Mercury is quite dense (5.4 g/cm3). We believe it to have a large metallic core (composed of iron or nickel-iron) with a thin rock mantle. This iron core is probably molten, for Mercury has a, albeit weak, magnetic field.

Structure of Mercury


Atmosphere
There is no atmosphere on Mercury, it is too hot and too small to retain an atmosphere. Thus, there is little erosion. That is why we still see the craters on the surface of Mercury.


History
It is believed that Mercury followed the four stages of formation. Like the moon, it cooled relatively quickly and is now geologically inactive. Surface erosion is limited however by the lack of an atmosphere.
Mercury's small size is attributed to it's distance from the Sun. So close to the Sun, the intense heat prevented most of the gases present from becoming part of the protoplanet.

It is expected that Mercury would be quite dense. So close to the sun, it must have formed out of metals that could condense at such high temperatures. Yet it is more dense than models predict. Perhaps a major impact soon after it differentiated shattered and blew away some of the rocky mantle, leaving an iron rich planet.



Venus

For quite a while, people believed that Venus would be very similar to Earth. After all, it is about the size of the Earth, has a similar average density, and is only 30 percent closer to the Sun (at an average distance of 0.7 AU from the sun). Only recently (in the last few decades) have we realized what an inhospitable world Venus is.

One unusual feature of Venus is that it has a very slow backward rotation (243 days); this may be caused by forces from the Earth's gravity, or it could be caused by some catastrophic impact early in its history.


Surface
Venus is completely covered in thick clouds, so we cannot see the surface form Earth.

However, radio waves do penetrate through the atmosphere, so astronomers mapped Venus using radar.
In 1962, Mariner 2 flyby was the first spacecraft to explore Venus. A Soviet spacecraft landed on Venus in the 1970s. The temperature on Venus is so hot that the spacecraft died within an hour of landing. However, before it died, it was able to take photos of the surface.

Much more information comes from radar observations by the Magellan spacecraft, which, in the 1990's, mapped the whole planet using radio waves.

Magellan image of Venus
Magellan image of Venus (color coded - blue regions are lava basins, brown regions are continental highlands)

About 75% of the surface of Venus is lowland lava plains. These plains have been distorted by stresses in the crust, producing the appearance of a grid (Lakshmi Plains). Above the lava plains are mountains, mountain ranges, and two continents. There are 2 continental regions: Aphrodite (about the size of Africa) and Ishtar (about the size of Australia).

Ishtar Terra is one of the highland regions. Collapsed caldera are seen there, indicating that there was once volcanism active in this region.

There is evidence of impact craters on Venus's surface: 24% of the surface is highlands. However the number of impact craters is considerably less than that of the Moon or Mercury. This indicates that the surface of Venus is much more active.

There is indication of recent volcanic activity. Magellan data has shown lots of volcanic craters, though no active volcanoes were seen. However, scientists believe that Venus still has active volcanoes. There are circular structures, called pancake domes, that appear to be areas where magma has risen suddenly to near the surface, and the surface has then collapsed.

Venus is seen to be a hot, dry, desert world, with extensive volcanism. Most of Venus' surface is rolling plains (65%), while 24% is highlands, and the rest is high volcanic peaks. Scientists believe that Venus still has active volcanoes.

The temperature near the surface makes the crust drier and stronger than earth's crust. It does not appear that Venus has moving tectonic plates. Surface features, such as the folded mountain range of the Danu mountains, are believed to be formed by convection currents in the mantle below the crust.

It is believed that Venus was entirely resurfaced about 300 to 500 million years ago.

Atmosphere
Venus' Atmosphere

The composition of the atmosphere is very different from the Earth:

The atmosphere is composed of almost all carbon dioxide (CO2) (96%)
There is some oxygen in the atmosphere, which indicates that, at one time, Venus may have had water, which was later lost.
The pressure at the surface is approximately 90 times the surface pressure of Earth's atmosphere. It would be like being 3000 feet under water.
The temperature at the surface is around 750 K (900 F). This is hot enough to melt lead.
There are clouds in Venus' atmosphere. These clouds are composed of sulfuric acid.
High winds of up to 200 mph flow through the atmosphere.
One main reason for the differences between Earth's atmosphere and Venus' atmosphere is the presence of water on Earth. It may be that both Venus and Earth initially had the same amount of CO2 in their early atmospheres. Earth's oceans dissolved the carbon dioxide, but Venus, if it had any water, did not have enough to dissolve great quantities of CO2. The CO2 in the atmosphere created a greenhouse effect that warmed up the planet even further.

The greenhouse effect

Why is Venus so very hot? The answer is the greenhouse effect, a process that also explains why the interiors of cars get so hot in the sunshine.

In a greenhouse light can travel through glass and heat the plants inside. The plants radiate infrared radiation that balances the heat they receive. But glass is opaque to infrared radiation, so it gets trapped inside the greenhouse Thus the temperature rises.

On Venus carbon dioxide takes the place of glass. Light from the sun can travel through the atmosphere to the surface of Venus. The heat is radiated back, but can't make it through the carbon dioxide. This heat is trapped. More sunlight travels in. More heat is trapped and the surface heats up even more. If there were any oceans on Venus, they would have been dried up from the intense heat, thus eliminating any possibility of purging the atmosphere of the carbon dioxide. The more carbon dioxide in the atmosphere the more heating there will be.

The Earth has much less carbon dioxide than Venus, but the amount is rising because of the burning of fossil fuel, including wood, coal, oil, containing carbon. This is the danger of global warming.


Interior
Venus' average density is similar to the Earth's. So it seems likely that Venus has an overall composition like the Earth, including a molten iron-rich core. Yet Venus has no detectable magnetic field, such as would be expected for a planet with a molten iron core. This may by due to Venus's very slow rotation (243 days).

Mars
Mars is the planet whose surface conditions are most like Earth's. It is smaller than Earth, and cooler, since it is 50% farther away from the Sun than the Earth, at an average distance of 1.5 AU.

But in some ways, Mars is like the Earth.

A day on Mars is 24 hours, 37 minutes long, compared to Earth's 24 hours.

Its inclination is 24 degrees compared to Earth's inclination of 23 degrees 27 minutes.

Thus Mars has seasons and days like the Earth, though its year is nearly 2 Earth years (1.88 Earth years


Surface
From earth, we can see polar ice caps on Mars and hazy surface markings. In 1976, two Viking spacecraft landed on Mars. The southern hemisphere is old and heavily cratered. The northern hemisphere has few craters.

Geological Map of Mars (the yellow regions are lowland plains and the blue regions are upland, heavily cratered regions)

There are volcanoes on Mars. Olympus Mons is the largest volcano at 370 miles in diameter and 16 miles high. We can contrast that with Mauna Loa at 140 miles in diameter and only 6 miles high. Olympus Mons does not show any signs of recent activity, but there are some relatively recent (geologically speaking) lava flows that might indicate the Olympus Mons is intermittently active.


There are great valleys and canyons on Mars. Valles Marineris or Mariner Valley is a deep canyon, as much as 4 miles deep and as much as 120 miles wide. Unlike features we call canyons on Earth, these Martian canyons were not cut by running water. They are cracks in the surface, caused by some crustal tensions. Water is believed to have played a later role in shaping the canyons however. There are features that look like landslides that may have been formed when water undercut the cliffs.

No liquid water flows on Mars today - the air pressure is too low and any liquid water will boil away. But there is evidence that liquid water was present on Mars. In the upper highlands plains, there are small twisting channels that looks like runoff channels. These channels may have carried surface runoff from rainstorms. If that is the case then Mars must have had a very different climate in the past. Then there are outflow channels. There are much larger than the runoff channels (longer and deeper). They look like features formed by huge volumes of running water, not just water from rainfall. The regions where we see these outflow channels contained large amounts of permafrost. Some kind of heating (maybe volcanism) released this frozen water and caused flooding and the carving out of the soil. In fact, some areas on Mars resemble flood erosion plains. This evidence suggest that years ago Martian temperatures must have been warmer. It could be that Mars once had a much thicker atmosphere than it has now. But, since Mars is smaller than either Venus or Earth, its gravity is lower and gases could more easily escape into space. As the atmosphere diminished, the temperature on the surface fell.

Another piece of evidence that water existed on Mars is through examining meteorites that originated on Mars. Chemical analysis of some meteorites indicates that the magma that formed the rock contained about 1.4% water. Also, one of the meteorites contains carbonate deposits that could have been formed only if liquid water was present in the rock sometime after it was formed.

One of the most prominent features on Mars is the polar ice caps. The seasonal polar ice caps grow and fade with the year long season changes are seen even from telescopes on Earth. The seasonal polar ice caps are not composed of frozen water, but of frozen carbon dioxide (dry ice). Underneath the seasonal ice caps is a thicker permanent ice cap, composed of frozen carbon dioxide and ice. The north pole permanent ice is primarily composed of water ice.

The Viking lander analyzed the Martian soil and found that it was composed of clays and iron oxides. During the winter, Viking photographed frost deposits (frozen water as opposed to frozen carbon dioxide).
There are major dust storms on Mars that occasionally blow up and hide all the surface features for weeks at a time.

Atmosphere
The atmosphere of Mars is mainly CO2, (like that of Venus) but the atmosphere is very thin. The pressure is only about 1% that of Earth. The temperature is quite cold - it can get down to -220 degrees F.

There are clouds of water vapor sometimes visible.

The atmosphere condenses at the poles to form ice caps. The polar ice caps are composed of frozen carbon dioxide (dry ice).

As mentioned before, liquid water cannot exist on Mars - the air pressure is too low. Any liquid water would immediately boil away. But, because there is indication that liquid water once did exist on the surface of Mars we conclude that, at one time, Mars had a thicker atmosphere than it does now.

Interior
The density of Mars is 3.9 g/cm3. This indicates that it is composed primarily of silicates (rocks) but that it might have a significant metal core. It has no appreciable magnetic field. That means that it probably does not currently have a molten iron core. However, Mars is large enough to have a molten core. Therefore, it is believed that Mars must have a molten core that may be some other compound (like an iron/sulphur compound) that is not a good conductor. Mars likely did not differentiate in the same way as the Earth.


Moons
Unlike Mercury and Venus, Mars has moons. Phobos and Deimos are Mars' two moons. They are very small and irregularly shaped and hard to see from Earth. They are probably captured asteroids.


Life?
The Viking spacecraft looked for signs of current life on Mars found but did not find any.
More recently there had been an announcement of evidence that there might once have been life on Mars. The evidence is from a meteorite that was found in Antarctica. Meteorites are easy to find there; there's not many other ways for rocks to get to be on top of ice. From its chemistry we can deduce that the meteorite once came from Mars. There is evidence of water. There are signs of complex organic molecules and also microscopic structures that resemble those made by very primitive forms of life on Earth. There is no suggestion that there is still life there, or that it evolved into anything more sophisticated. These results are very controversial.

More recent study suggests that this may be a false alarm, but if it is true, then it is one of the most exciting discoveries of the last 20 years.


Pathfinder
Recently the Mars Pathfinder mission landed a surveyor on Mars. The purpose of Pathfinder was to examine the atmosphere, weather, and surface of Mars. The little rover examined rocks and soils on the surface. The results of Pathfinder indicate more differentiation of volcanic materials than previously though. That may be caused by more crustal activity early in Mars' history. Mars appears to have erosion features caused by winds and flowing water. Rocks appear to have been weathered sometime in the history of Mars. Sand is present on the surface, also indicating weathering processes by wind and water.

Comparative Planetology

Atmospheres
The atmospheres of the terrestrial planets are so different that we must ask why. The answer is still controversial, but the most likely explanation is that CO2 is widely formed by volcanoes. Earth is the only planer with liquid water. Water can dissolve carbon dioxide (think of carbonated beverages) in its oceans, then turn it into rocks such as limestone. Thus Earth can get rid of CO2 but Venus cannot. Nitrogen (which is the second most common gas on Venus) then becomes the most common gas on Earth, because it does not react with anything. Because of life on Earth some more of the carbon dioxide is turned in to Oxygen, though the details of how this happened are still uncertain.
On Mars much of the carbon dioxide must have frozen out.