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The Puzzle of Martian Meteorites
Alien54 writes "Recent analysis of several new Martian meteorites is confounding planetary scientists. To put it simply, an awful lot of the Martian meteorites are way too young. According to this thi s story found at Space.com, standard theories predict that most meteorites from Mars should be billions of years old. However, almost half of the known rocks from mars are under 200 million years old. These results open up a Pandora's box of questions. The discussions should be interesting."
Maybe I've been wrong about this whole religion thing. Maybe there is a God and he's messing with our minds!
A lot of those craters are our testament to NASA's attempt at a Martian lander.
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Until we actually return samples of rock from Mars, I cannot understand how we can say they are of Martian origin. They might not be of the Earth, I'll allow that. I just think calling them "Martian" is bad science.
Graham
Graham
Linux - Fast Pane Relief
Isn't Mars the closest planet to the asteroid belt? If so, and assuming that that occasionally an asteroid gets knocked into an eccentric orbit, might this not explain some aspects? Of course, that's dependent on whether there are young rocks in the belt. If there aren't, pardonez mon air chaud. ;)
-TBHiX-
Forgive Babelfish, for it knows not what it translates.
The conclusion of the article says it all; that they need to send a lander to bring back samples from Mars as soon as possible.
IANAEG or CC (Exo-Geologist or Cosmo-Chemist):
I say this because until that happens, how can we be so sure that these rocks actually came from Mars? Yes, the chemistry is similar, to what we THINK Mars' chemistry is, based on our very limited (and no direct) observations, but if the planets, Mars included, formed by accretion of dust particles in space around the early Sun, then it stands to reason that maybe not ALL of the materials of similar Martian chemistry accreted to Mars. There could be any number of asteroids made of similar materials floating out there between Mars and Jupiter, and periodically colliding, getting melted, and sent Earthward. Sure, the stats may be against it, but I don't believe we really know all that much about the smaller residents of the asteroid belt.
I'm not saying that these rocks are not from Mars, but I'm saying that maybe it's time to entertain alternative theories as to these rocks origins, because the data doesn't jibe.
if it ain't broke, then fix it 'till it is!
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
Best scientific answer to date: It beats the shit outta me.
The scientists are just in denial about the really obvious answer.
The inhabitants of Mars are firing these little rocks at us just to mess with our heads.
"Here Earth-scum! Take a gander at *foom* this one! Just quit bombing us with those damned probes!"
Argh. Waaayyyy too much coffee today....
Well -not being a geologist myself- if memory serves, C-14 dating is *only* really useful for biological structures. I'd assume they are using isotopes of other elements.
j
I doubt it. There are many more isotopes, each with much greater half-lives than c14. Each is valid for a different range of years. For example, from http://www.talkorigins .org/faqs/faq-age-of-earth.html#howold:
The most direct means for calculating the Earth's age is a Pb/Pb isochron age, derived from samples of the Earth and meteorites. This involves measurement of three isotopes of lead (Pb-206, Pb-207, and either Pb-208 or Pb-204). A plot is constructed of Pb-206/Pb-204 versus Pb-207/Pb-204.
You quitting proves that the karma kap worked. The most annoying of the whores shut up. --CmdrTaco
Obviously the Martians were a race of giant creatures with immense strength and incredibly keen eyesight. Their primary sport was "Hit the Blue Dot", an odd pasttime which consisted of chucking rocks towards the earth. Any that managed to nail it, of course, got all the girls. Unfortunately, most of them were bad aims, as the Martian race obviously died out millions of years ago.
End of lesson. You may press the button.
First you need to sent a probe to mars that
launches a smaller probe to the surface
from about 200mi above the surface. The little probe (launched from 200km) would slam into the
martin surface....
damn it...they already tried that
AdFuel
This is perhaps the best argument yet for pushing ahead aggressively with manned missions to Mars. It shows that we can learn only so much about an object by looking at it with telescopes. Even when that object is extemely close by, all things considered. Satellites and unmanned landings have clearly not given us the information we desire.
If we want to unlock Mars' secrets, we've got to get there ourselves.
We must respect evil, and we must make evil respect us.
why yes, carbon-14 can only be used accurately for that long because of it's short half-life, but there are many other unstable isotopes that have been used to date materials - isotopes with much longer half-lifes. some include:
potassium->argon
argon->argon
rubidium->strontium
etc etc.
these isotopes let you accurately measure the date of materials way beyond that of carbon-14 dating.
I can see it now. "Well, God only made Earth look really old. He didn't spend as much effort making Mars look old. Really, they're both only 6000 years old and this hundred-million years is a facade made to trap the satanic atheists."
(Modified only slightly from an actual IRC quote).
--
Ben Kosse
--
Ben Kosse
Remember Ed Curry!
Did anybody consider that maybe the Martians have only recently (in geologic time) evolved to the point that they could build machines powerful enough to lob the darned things at us?
It's probably enough fun to keep them pretty busy nowadays - I imagine with Martian weather things could otherwise be a little monotonous.
- -Josh Turiel
-- Josh Turiel
"2. Do not eat iPod Shuffle."
that the process of knocking rocks off of Mars into space and their subsequent reentry thru the earth atmosphere would seriously disrupt the ability to date them by the isotope decay methods described. Therefore, a robotic Mars mission to bring samples back is justified. M&M's sold separately.
try { do() || do_not(); } catch (JediException err) { yoda(err); }
Had a conversation with my brother about something similar to this. The topic basically was, "The universe isn't as old as scientists believe". The posit: the universe (and all physical actions) are slowing down over time.
To explain: we know the age of X because of carbon dating. Carbon dating assumes that radioactive decay is a constant. What if, in the past, things happened much faster? Light travelled faster, radioactive isotopes decayed faster, etc. And as time went on, the physical properties assumed to be constant slowed down.
I dunno -- I know my VISA bill grows faster in the present than in the past, but VISA physics defies all rational thought. But, it's an interesting idea.
Potato chips are a by-yourself food.
I think i have finnaly figured out what NASA is up to, a long time ago the indigineous intelligent peoples of mars was bombarding us with meteors, and after 200 million years we are finnaly returning fire with billion dollar satalites and ground survey equipment!
Kick thier martian green ass NASA!
I am Jack's complete lack of surprise. -Fight Club
C-14 is only useful for dating PLANT material or animals that eat (directly or indirectly) recent plants.
Anyone who watched Mission to Mars will doubtless realize that these recent meteorites were generated whent he martian emigration fleet blasted off.
I mean, come one. It's so obvious.
Disclaimer: I saw that on a transatlantic flight while suffering jetlag and sleep deprivation. i was bound to get some funny ideas, okay?
-J
Karma: T-rexcellent.
- Carbon-14: 5730 years
- Uranium-235: 704 million years
- Potassium-40: 1.3 billion years
- Uranium-238: 4.5 billion years
- Thorium-232: 14 billion years
- Rubidium-87: 48.8 billion years
So if some other isotopes are present, they could easily do the dating.Also, how are half-lifes measured to millions of years? We've only known about this stuff for about 100 years...
Bruce
Bruce Perens.
Article: "Einstein Explains Theory of Relativity"
Slashdotter (knows nothing, but states the irrelevent obvious): "When is Einstein going to learn that F = MA??"
Moderator: Ooooohhhh Aaaaahhhhh Mark this as insightful!
--
Sometimes it's best to just let stupid people be stupid.
Please see google and learn for yourself.
I think you will find it fascinating.
No matter how much we think we know about dating things, it's still guesswork. Unless you or the person claiming to know the age were there when the object was "created" (really just matter being converted, we don't "create" any matter), you/they can only guess at its age. We can guess fairly accurately at relatively recent things, but we can't even say with full certainty what the C14 level, or any other age determining factor, was 1000 years ago, let alone exponetially higher ages.
:)
We can't guess right all the time, so don't expect all guesses (hypotheses even) to be right, and don't be so surprised when they're wrong.
About a year ago I was on campus watching a lecture being given by one of the Profs from the Aerospace and Mechanical Engineering department here at the U... (U of A is a big school for space-sorta stuff)
And now, why this is relevant:
There was some speculation that very early/primitive forms of life may have existed on Earth during the time this collision occured. The debris from the collision could very well have contaminated the rest of the solar system with life, including Mars. ALH84001 may just be the ancestor of a hunk of material that came off of earth, made it to mars, then got blown back here. Weird, eh?
By the way, 1998-2000 PROPAGANDA Image Archive CDs are now available. Click the "Enjoy!" link below...and enjoy.
Bowie J. Poag
Bowie J. Poag
For example, with potassium-argon dating, how do we:
- know that potassium-40's half-life is 1.3 billion years? Even over 10 years, that's a part-per-billion experiment.
- know that there wasn't argon trapped in the rock along with the potassium in the first place?
Some good scientists admit these assumptions up front, for example http://www.icr.org/research/sa/sa-r03.htm clearly says:True. But by measuring what portion of it decays in 100 years, we can extrapolate the half life.
75% decayed => half life is 50 years
50% decayed => half life is 100 years
25% decayed => half life is 241 years
10% decayed => half life is 658 years
1% decayed => half life is 6897 years
.1% decayed => half life is 69280 years
and so on.
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--
E_NOSIG
A Brief Conversation with NASA's Mars Program.
From the story:
The age of the Martian surface has been calculated by examining the number of craters on Mars, Mittlefehldt explained. The oldest surfaces would have been exposed to meteorite impacts from space for the longest time, and thus would have the most craters on them. Young surfaces would be relatively free of craters.
Using the current understanding of crater density, a maximum of 15 percent of the Martian surface could be as young as 175 million years old, Mittlefehldt said. Even getting that high of a percentage is really stretching the model, he said. It simply doesn't make sense that half the meteorites from Mars and half the big impact events that sent them to Earth just happened to hit the 15 percent of the surface that is young, he said.
This method of determining the surface age of Mars seems to assume that the meteorite strikes occur at consistent intervals. Therefore, the older the surface, the more impact craters. However, what if there was some reason that a surface which is relatively new (say, 175 million years old) has a much higher density of crater impacts for some reason? Here's what I think: There were very high levels of volcanic activity when these meteorites we're finding were formed. Soon after, one or several large impacts caused a great deal of this newly formed rock to be thrown into space. Several bits made it to earth where we can now puzzle over them, but more importantly, most fell back to Mars, causing heavy cratering over most of the surface.
Thus, the surface of Mars has seen recent volcanic activity, but still shows heavy cratering because the same impact that sent the meteorites to us also sent up large rocks that came back down to form many new impact craters; many more than would be normally be formed in that time span.
But, IANAMG (Martian Geologist). Is any one here who is know if this would work?
...this hardly deserves "Insightful". It's pretty content-free. Note the needless repetition of ideas, malapropisms, and use of filler such as "ever-expanding rapid rate".
Read carefully. The poster could have said the same thing in much less space:
I wouldn't accept this from a student, let alone give it anything better than a "D".
DNA just wants to be free...
-Pete
I'm not supposed to say this in public, but since it's slashdot, it'll be written off as blatherings...
Humanity started on Mars billions of years ago.
They seeded Earth as a new place to live, as they wasted their natural resources and destroyed their own planet.
They also seeded Earth with low-level lifeforms whom they could use as beasts-of-burden and slave labor.
All those crop circles and such you hear about today are people who still have this Mars programming in their subconscious and are making landing sites for their masters.- whom no longer exist
And it's also the reason for the various odd land formations, like the Nazca works in South America.
However, something went horribly wrong on Mars before the seeding and transplanting was complete...likely some kinda war which wiped out all natural life on that planet. We're still looking into that.
Thus, earth was left to develop on it's own- and look where we are today! Not too bad...
The thing we need to worry about is when the beings who seeded Mars come back to look in on their experiment. Will they know we're related? Or an aberration?
Wait and see, young ones, wait and see.
---
Kinda like Moe, but just a little more Kool
Take a homogenous magma composed of some Sr an Rb. Now let it cool thus forming various minerals such as plagioclase, pyroxene, and olivine.
Now: Rb87 decays to Sr87. Sr86 is stable and is not a by-product of the radioactive decay of another isotope. The number of Sr87 atoms in a mineral is given by
Sr87 = (Sr87)o + Rb87 * ( exp(at) - 1 )
where (Sr87)o = original amount of Sr87 at the time of crystalization, Rb87 = current amount Rb, a=decay constant, t=time since crystalization. Now divide by the amount of Sr86.
Sr87/Sr86 = (Sr87/Sr86)o + Rb87/Sr86 * ( exp(at) - 1 )
If the initial ratio of Sr87/Sr86 is uniform throughout the rock at the time of crystalization (as it turns out, this is a good assumption), then this the above equation is the equation of a straight line where (exp(at)-1) is the slope, and (Sr87/Sr86)o is the y intercept.
Now measure the various isotopic ratios from various minerals in different parts of the rock. The decay rate is known from the results of laboratory measurements. Solve for t.
Well, I'm not really talking about carbon dating, but using it as an example for the whole of the idea. If it makes you feel better, replace "carbon dating" with "speed of light".
And you are allowed to laugh at my ignorance. In my family, I'm one of the ones holding the bottom of the intelligence ladder. I've got an electrical engineer father, a math teacher mother, two mechanical engineering uncles, a cousin with a 4.0 in Aerospace engineering and my brother who is finishing a computational engineering degree. I'm the creative one (euphamism for "well, at least he GOT a degree...").
I don't present it as gospel, but it is a philosophical argument that occurs in the scientific community (at least, the parts that I'm familiar with). It's called Uniformitarianism, or something similar. All things continue as they always have.
I find it sad, though, that you outright dismiss the idea. Everything I've ever read or heard from really smart people mentions that they don't believe that they know everything, or indeed a lot about anything. The quest for knowledge stops as soon as you believe that you know all there is to know.
I don't claim to know the answer. I don't even claim there is an answer. I just claim that I find it an interesting thing to talk and think about. It gives a different perspective on things, which may lead to a greater understanding of the problem, just as it may lead to a two hour wanking session. I make no guarantee or warranty.
Anyway, I appreciate the links. They've got good info, and I learned something new, which is cool. However, I will always keep in mind all of the things that science KNEW was true, until somebody discovered something else that discounted the earlier theory, which led to new things that science now KNEW was true... ad infinitum. They are working theories -- and good ones, I might add -- but only theories.
Potato chips are a by-yourself food.
That maybe these rocks are all the result of a large Mars meteor strike 175 million years ago?
The meteor struck, blasted a crapload of molten rock to escape velocity, where it cooled and solidified, resetting this isotope 'clock'.
-josh
How do we know the half-life of $element
Take a kilo of $element (measured to an accuracy of 1 ppm): Given the atomic weight of $element, you know how many atoms of $element you have (to an accuracy of 1 ppm). You know that when $element decays it emits N $particles: so set up a particle counter and count how many $particles are emitted in $time: This give you the number of atoms that decay per unit time for that many atoms. You derive the decay rate of $element from that.
Given that $element1 decays into $element2, how do we know that there wasn't any $element2 in the mix to start with?
In the cases that are used, the decay product of $element1 isn't any old isotope of $element2, but an isotope that is not produced by any other form of decay. Therefor, you know that every atom of $element2<isotope-x> was produced by the decay of an atom of $element1.
www.eFax.com are spammers
I like your explaination of that. It is logical and seems to hold merit. Now, they claim that the rocks came to earth at different times (and spent different amounts of time in space on the way) so they couldn't have come from the same 'initial impact'.
To this I say, there was the initial impact (followed by your explaination above for the multiple craters). Then, there was a great out-pouring of many rocks into space. The earth caught a few of them on their way out from Mars (on their trip 'away' from the sun) and the others circled in various 'shaky orbits'(elliptical) until they fell to other planets, fell to Earth (some on their trip back 'towards' the sun), fell into the sun itself, or even fell back to Mars. Wouldn't that explain the various amounts of time in space, plus the fact that they arrived on Earth at various times?
Or am I missing something obvious that the article didn't mention? My feeling on this is that the 'Martian Geologists' are too close to the situation and are trying to look for the most complex and 'other worldly' type of explaination. Much like computer technicians get frustrated as hell because they can't figure something out (and they fight it and fight it looking at all of these complex possibilities), then some nearly computer illiterate person says, "hey, what about this?" and the techy smacks himself in the head for being a moron.
I say we 'open source' science, and put them (the scietists) on usenet and mailing lists that are easily accessible. Sure, they would get four hundred times as many useless messages as they got good messages, but I think it would be worth it if they got a few 'simple people's' explainations.
Bite my yammer.
The first book of the trilogy is "Out of the Silent Planet." The Silent Planet is Earth. Or at least what the Malacandrans refer to earth as. They call Earth "The Silent Planet" because its ruling eldila have become rebellious against Maleldil, the governing Spirit of the universe, who Ransom presumes to be the same as Jesus. Mars, incidentally, is Malacandra.
----
Celebrate the finer things in life
This sounds like additional support for Dr. Tom Van Flandern's Exploded Planet Hypothesis.
I agree - great ref to C.S.Lewis' Space trilogy. The books are, you know, written by a Christian Fundamentalist. While Clive (hist first name) would enjoy the origin of the rocks (from Mars, meteors spun 'round Mars to knock us on our noggins, etc) - the main character Ransom does believe in Creation, the wonderful expanses of the creation and yes, the heavenly hosts of each planet all bow down to a Most High Oyarsa. So maybe they are throwing the rocks at us. One of the posts said we don't create stuff anymore. Who did? . . . So maybe those on Malacandra (Mars) are tossin' the rocks at our noggins to get us to focus less on the age of the rocks (neat stuff to know) and MORE on the One who created them? (The Object Class of life from which all other class get their attributes!) If you happen to not see things this way, it was your reference to a solid Christian treatise in Science Fantasy that got me going) PS: I do enjoy your subtitles. Usually fun, great play on words, or like this story a good play on ideas by refercne. And keeps out minds going when we con't know what the subtitle refers to.
You shall know The TRUTH, and THE TRUTH will set you free.
Back on topic, myself: I really don't understand how the Martian rocks get to Earth to begin with, but am enjoying watching the theories fly about looking for a place to land. Anyway,<ugh> 'rock on'. </ugh>
Now hiring experienced client- & server-side developers
-- @rjamestaylor on Ello
Let me postulate a theory:
1. There was life on Mars. One of their largest structures, which only partially survived, was a face.
2. The Martians thought, "The danger from the sky will never hit us," and 200 million years ago they didn't see it coming.
3. The impact was so great, they all perished; so great, in fact, that it blew chunks of the planet into Earth's path.
4. The building blocks of life were contained in ... Nah, that's going too far. ;-)
Nice conspiracy theory, even without 4. This tells me we need to devote more resources to our "eyes."
Thing 1
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I feel fantastic, and I'm still alive.
This will probably get shot down by a passing astrophysicist, but anyway:
Could a large meteorite have impacted on Mars circa 200 million years ago and thrown pieces of rock clear of the planet?
I don't know much about the surface of the red planet, but is there a large enough crater to support this?
Alternatively, such a large impact could have made a serious hole in the crust, creating a large volcano. This could have been the origin of Olympus Mons (the monster volcano roughly on Mars' equator).