Let’s say I have a vial of powdery material. I know where it was collected (but that’s classified) but not how it got there.
Let’s also say that I have reason to believe that this material did not originate on Earth.
Would I be able to conclude, using only modern day technology, with some certainty, that this material is, for example, lunar dust?
Asteroid dust?
Dust from the rings of Saturn?
Oort Cloud dust?
Something from outside this solar system entirely?
My guess is that we would be quite limited in what we could compare it to - probably just lunar dust, maybe Martian dust, asteroid dust, perhaps cometary/Oort cloud dust?
And that at best we could say “this matches the chemical composition of asteroids known to come from the asteroid belt”, but there’d be no way to know it doesn’t come from an unknown terrestrial source.
But perhaps counting isotopes or something like that could give a more definitive answer?
Eta: purely hypothetically, I do not “need answers fast”.
May I state first of all that after reading the thead title I am deeply disappointed to open this thread and discover that you are not in fact in possession of some unidentified material of mysterious extraterrestrial origin. Bloody clickbait if you ask me.
A test of various isotope ratios would do it. Each parent body in the solar system has different isotopic compositions. Here’s how one source puts it:
A single chemical element may be found under several variants depending on its number of neutrons. These variants are called ‘isotopes’. Thus natural occurring oxygen is composed of three stable isotopes which are 18O (with eighteen neutrons), 17O (seventeen neutrons) and 16O (sixteen neutrons). Scientists established the diagram below showing the ratio of amounts of 18O and 17O contained in terrestrial rocks, lunar samples and several meteorites. In all the rocks that belong to the same parent body the oxygen isotopes 17O and 18O is ratios lie on the same line. This results in the fact that the rocks which have the same origin are aligned on the same line. For example the terrestrial rocks are all grouped on the same line. The Moon is also placed on this line, suggesting that it was formed from the Earth. The diagram also shows that the SNC meteorites (for Shergottite, Nakhlite and Chassignite, three meteorite groups then recognised as from Mars) are aligned together, suggesting that these meteorites come from the same parent body. Our meteorite Nakhla gave its name to the group Nakhlite and, thus, belongs to the SNC meteorite group.
So we test your material. We learn that it is not likely from Earth. But where is it from? We know isotope ratios specifically for the moon and Mars, so we would be able to name that location with a fair amount of confidence. Other than those two, we would be able to pin down if it originated from one of the dozens of other parent bodies that we have identified by studying meteorites but do not have a name for. And there is one group in particular called the HED meteorites (Howardites, Eucrites and Diogenites) that probably came from the asteroid Vesta.
Well, if I was in possession of such material, for example, due to my hypothetical work with a covert organization dedicated to combatting an alien threat, I wouldn’t be able to tell you about it, because I couldn’t risk them finding out.
There are more than 50 known parent bodies of iron meteorites alone. Each being an asteroid that was large enough to melt and differentiate into a metallic core and stony crust, then was completely shattered so that bits of the core reach Earth.
We need more context. Do we need to allow for the possibility that an Earthbound lab might be trying to deliberately fake something that looks like it came from a particular source?
We should be considering that possibility, so if we can get as far as “This matches the chemical and isotopic composition of Martian dust” then the next step will be to figure out whether you could source these components on Earth and if so whether anyone has done so. That should keep XCOM’s forensic accountants busy for a while, right?
So lunar dust, terrestrial rock, and a number of asteroid belt objects are all sampled well enough that if the dust came from there isotopic analysis would tell us so.
But it would need to be dust we have samples of, wouldn’t it? We couldn’t test the dust against, say, Satrun’s rings, because we don’t have any of that material here on Earth?
Would the only means to check the dust against Saturnian ring dust be to do a collect and return mission, or would long range spectrometry do anything here? I wouldn’t imagine long range spectometry can differentiate between isotopes?
If not, could we at least cut down the time it takes to get an answer by sending a probe that can collect and analyze the dust without returning?
As mentioned in the first article I linked, martian meteorites were identified because of trapped gasses that match the atmosphere of Mars as sampled by Viking:
Mars’ atmosphere is known since analysis in situ performed by the NASA’s Viking probes in 1976. Scientists found out that the abundance of rare isotopes (neon, argon, xenon, krypton) trapped in the meteorite EETA 79001 was exactly the same as the composition of Mars’ atmosphere. This substantial correlation suggests the meteorites have a large probability to be from Mars.
Scientists thus have the evidence of EETA 79001’s Martian origin. Moreover, as EETA 79001 shows the same oxygen isotopes composition as SNC and is on the same line of the diagram, we can conclude that EETA 79001 and the SNC, including Naklha, come from one single parent body: the planet Mars.
I imagine a similar instrument could be sent to Saturn to collect and sublimate a sample of ring material (which is mostly water ice iirc) and measure the composition of that.
Also mentioned in the article is why there is some speculation that a type of meteorote is from Mercury:
Most of the meteorites found on the Earth appear to be fragments from the asteroid belt between Mars and Jupiter and other ones originate from the Moon and Mars. However, another origin is possible.
In early 2012, the extra-terrestrial rock NWA 7325 was found in the Moroccan desert. The owner of the 35 fragments of the meteorite immediately noticed the intense green-coloured heart and the very shiny crust of the rock and sent a sample to the Washington University for further analysis.
After a scientific investigation, scientists discovered a substantial quantity of magnesium, aluminium and calcium silicates but a very low concentration of iron. This chemical composition closely resembles observations on Mercury’s crust ran by the probe Messenger, in orbit around the planet. Researchers also undertook the study of NWA 7325’s oxygen isotope composition to understand its parent body signature. The results of the study support the evidence that NWA 7325 belongs to a differentiated body. However its oxygen isotope composition does not match the Earth or Mars. Scientific investigations have not resolved the mystery of NWA 7325’s origin yet, but showed some evidence of a possible Mercurian origin.
If this hypothesis was confirmed, NWA 7325 would be the first meteorite to come from Mercury ever identified on Earth. To confirm or refute a Mercurian origin, the study requires a comparison with Mercury’s rocks, either with return samples from the planet, such as for the Moon, or with analyses in situ, such as for Mars.
If you have a rock that contains certain elements, you can perform radiometric dating to determine its age. If your sample is more than 4.5 billion years old, it came from outside the solar system.
Hold on a sec. He might have it but is just playing it close to the vest because he is worried about some 3-letter agency kicking in his door and taking both him and the vial.
