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Started by a425couple
Thu, 29 Aug 2024 09:21
200 meteorites on Earth traced to 5 craters on Mars
Author: a425couple
Date: Thu, 29 Aug 2024 09:21
Date: Thu, 29 Aug 2024 09:21
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And this is why I personally would not be at all surprised if future exploration discovers life on Mars with genetic connections to life on Earth. "panspermia" from https://www.space.com/mars-meteorites-5-craters-tharsis-elysium 200 meteorites on Earth traced to 5 craters on Mars News By Victoria Corless published August 23, 2024 Astronomers have traced the origins of 200 meteorites to five impact craters in two volcanic regions on Mars, known as Tharsis and Elysium. Comments (3) When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. craggy grey rocks float above a reddish orange planet Illustration of a large meteorite above Mars. (Image credit: Pitris/Getty Images) Believe it or not, debris from Mars has frequently made its way to Earth after powerful impacts hit the Red Planet's surface and launch it into space. There have been at least 10 of these meteorite-forming events in Mars' recent history. When these massive impacts occur, meteorites can be flung away from the Red Planet with enough velocity that they break free of Mars' gravitational pull to enter orbit around the sun, with some eventually falling to Earth. Scientists at the University of Alberta have now traced the origins of 200 of these meteorites to five impact craters in two volcanic regions on Mars, known as Tharsis and Elysium. "Now, we can group these meteorites by their shared history and then their location on the surface prior to coming to Earth," said Chris Herd, curator of the university's meteorite collection and professor in the faculty of science, in a statement. Meteorites fall to Earth all the time — an estimated 48.5 tons (44,000 kilograms) of meteorite material falls each day, according to NASA — though the majority make it to the surface as tiny unnoticeable particles of dust. Determining their origins can often be difficult, but in the 1980s, scientists became suspicious of a group of meteorites that appeared to have volcanic origins with ages of 1.3 billion years. This meant that these rocks had to have come from a celestial body with recent (in geological terms) volcanic activity, making Mars a likely candidate. However, proof came when NASA's Viking landers were able to compare the composition of Mars' atmosphere with trapped gases found in these rocks. Identifying exactly from where on Mars they originated was previously difficult to do. The team noted in their paper that this difficulty arose from using a technique called spectral matching, a technique used to identify and compare the composition of materials by analyzing the patterns of light they absorb or emit. However, this method is limited by factors such as terrain variability and extensive dust cover, which can skew spectral signals, especially on younger terrains like Tharsis and Elysium. But knowing exactly where these Martian meteorites came from would allow scientists to better piece together the planet's geological past. Get the Space.com Newsletter Breaking space news, the latest updates on rocket launches, skywatching events and more! Your Email Address Contact me with news and offers from other Future brands Receive email from us on behalf of our trusted partners or sponsors By submitting your information you agree to the Terms & Conditions and Privacy Policy and are aged 16 or over. "[It would] enable the recalibration of Mars' chronology, with implications for the timing, duration and nature of a wide range of major events through Martian history," said Herd. "I call that the missing link — to be able to say, for example, the conditions under which this meteorite was ejected were met by an impact event that produced craters between 10 and 30 kilometres across." a dark grey pockmarked rock A Martian meteorite known as Amgala 001, found in Western Sahara in 2022. (Image credit: Wikimedia Commons/Steve Jurvetson) The team combined high-resolution simulations of impacts into a Mars-like planet. "One of the major advances here is being able to model the ejection process, and from that process be able to determine the crater size or range of crater sizes that ultimately could have ejected that particular group of meteorites, or even that one particular meteorite," said Herd. The model's output allowed the team to determine the impact events' "peak shock pressures" and the duration the rocks were exposed to these pressures. This can be determined from "shock features" observed in the meteorites—for example, unique mineral changes, impact glass, and special fracture patterns. From this data, Herd and his colleagues were able to estimate the size of the impact craters that could have launched the meteorites, as well as how deep the rocks were buried before the impact. Although these depth estimates come with some uncertainty, the researchers compared them with the local geology of possible source craters and the characteristics and ages of the meteorites to see if they align. RELATED STORIES: —  Mars is an asteroid punching bag, NASA data reveals  — The mystery of how Mars meteorites reach Earth may finally be solved  — Mars meteorites reveal clues about what lies within the Red Planet "[Our modelling approach] allows us to say, of all these potential craters, we can narrow them down to 15, and then from the 15 we can narrow them down even further based on specific meteorite characteristics," he said. "We can maybe even reconstruct the volcanic stratigraphy [the geological record], the position of all these rocks, before they got blasted off the surface." This could help the scientists better understand when volcanic events on Mars occurred, the different sources of Martian magma, and how quickly craters formed during an era of low meteorite bombardment on the Red Planet known as the Amazonian period, some 3 billion years ago. "It is really amazing if you think about it," Herd added. "It's the closest thing we can have to actually going to Mars and picking up a rock." Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: community@space.com. Victoria Corless Victoria Corless Contributing Writer A chemist turned science writer, Victoria Corless completed her Ph.D. in organic synthesis at the University of Toronto and, ever the cliché, realized lab work was not something she wanted to do for the rest of her days. After dabbling in science writing and a brief stint as a medical writer, Victoria joined Wiley’s Advanced Science News where she works as an editor and writer. On the side, she freelances for various outlets, including Research2Reality and Chemistry World.
Re: 200 meteorites on Earth traced to 5 craters on Mars
Author: R Kym Horsell
Date: Thu, 29 Aug 2024 18:16
Date: Thu, 29 Aug 2024 18:16
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In alt.astronomy a425couple <a425couple@hotmail.com> wrote: > And this is why I personally would not be at all surprised if > future exploration discovers life on Mars with genetic connections > to life on Earth. "panspermia" ... At this point a good bet I think. In the past few years theyve confirmed all the major ingredients of life-as-we-know-it have been found in meteorites and are now assembling a list of things found in asteroid return samples. Building block of life found in sample from asteroid Ryugu Space.com, 21 Mar 2023 The discovery of the nucleobase uracil is a big step forward for astrobiology. One of the four nucleobases of RNA has been discovered in samples retrieved from the asteroid Ryugu, providing the strongest evidence yet that the organic building blocks for life on Earth came from space. All of the bases in DNA and RNA have now been found in meteorites Science News, 26 Apr 2022 Space rocks that fell to Earth within the last century contain the five bases that store information in DNA and RNA, scientists report April 26 in Nature ... Could the Blueprint for Life Have Been Generated in Asteroids? NASA.gov, 26 Apr 2022 Using new analyses, scientists have just found the last two of the five informational units of DNA and RNA that had yet to be discovered in ... Scientists say the 'R' in RNA may be abundant in space Phys.org, 8 Apr 2016 New research suggests that the sugar ribose - the "R" in RNA - is probably found in comets and asteroids that zip through the solar system ... Maybe 10y back I was subcontracted to work on the chemistry seen in space. 10s of 1000s of chemical reactions are possible with what has been detected in gas clouds all over. For some not-clear-to-me-at-the-time reason I was told to keep any results under my hat. The workd of course was funded by the US military. Maybe I should dig it out and have a look at it again. I wasnt tuned in to looking at the carbon chemistry. I was infatuated by the quantum chemistry of boron hydrides that showed structures "similar" to RNA could self-construct at low temps. The calculations on that suggested over enough time the compounds become very complex indeed. Hoyle would have been tickled pink.
Re: 200 meteorites on Earth traced to 5 craters on Mars
Author: "Jim Wilkins"
Date: Thu, 29 Aug 2024 18:37
Date: Thu, 29 Aug 2024 18:37
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"R Kym Horsell" wrote in message
news:vaqdt4$26s2$1@nnrp.usenet.blueworldhosting.com...
Maybe 10y back I was subcontracted to work on the chemistry seen in
space. 10s of 1000s of chemical reactions are possible with what
has been detected in gas clouds all over. For some
not-clear-to-me-at-the-time
reason I was told to keep any results under my hat. The workd of course
was funded by the US military.
Maybe I should dig it out and have a look at it again. I wasnt tuned in
to looking at the carbon chemistry. I was infatuated by the quantum
chemistry of boron hydrides that showed structures "similar" to RNA
could self-construct at low temps. The calculations on that suggested
over enough time the compounds become very complex indeed. Hoyle would
have been tickled pink.
-----------------------------
These are DNA & RNA components.
https://en.wikipedia.org/wiki/Guanine
"A Fischer–Tropsch synthesis can also be used to form guanine, along with
adenine, uracil, and thymine. Heating an equimolar gas mixture of CO, H2,
and NH3 to 700 °C for 15 to 24 minutes, followed by quick cooling and then
sustained reheating to 100 to 200 °C for 16 to 44 hours with an alumina
catalyst, yielded guanine and uracil:
10CO + H2 + 10NH3 → 2C5H8N5O (guanine) + 8H2O
Another possible abiotic route was explored by quenching a 90% N2–10%CO–H2O
gas mixture high-temperature plasma."
Re: 200 meteorites on Earth traced to 5 craters on Mars
Author: danny burstein
Date: Fri, 30 Aug 2024 01:26
Date: Fri, 30 Aug 2024 01:26
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In <vaqdt4$26s2$1@nnrp.usenet.blueworldhosting.com> R Kym Horsell <kymhorsell@gmail.com> writes: >In alt.astronomy a425couple <a425couple@hotmail.com> wrote: >> And this is why I personally would not be at all surprised if >> future exploration discovers life on Mars with genetic connections >> to life on Earth. "panspermia" >... >At this point a good bet I think. >In the past few years theyve confirmed all the major ingredients of >life-as-we-know-it have been found in meteorites and are now >assembling a list of things found in asteroid return samples. [snip] Brings to mind this fascinating experiment in 1952 in which a group of subversives at Univ of Chicago. I'll quote a bit from Wikipedia: "The Miller-Urey experiment[1] (or Miller experiment[2]) was an experiment in chemical synthesis carried out in 1952 that simulated the conditions thought at the time to be present in the atmosphere of the early, prebiotic Earth. It is seen as one of the first successful experiments demonstrating the synthesis of organic compounds from inorganic constituents in an origin of life scenario. The experiment used methane (CH4), ammonia (NH3), hydrogen (H2), in ratio 2:2:1, and water (H2O). Applying an electric arc (the latter simulating lightning) resulted in the production of amino acids." https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment They were, of course, ridiculed. Until lots of high school chem labs (remember those?) replicated the work -- _____________________________________________________ Knowledge may be power, but communications is the key dannyb@panix.com [to foil spammers, my address has been double rot-13 encoded]
Re: 200 meteorites on Earth traced to 5 craters on Mars
Author: "Jim Wilkins"
Date: Fri, 30 Aug 2024 08:49
Date: Fri, 30 Aug 2024 08:49
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"danny burstein" wrote in message news:var74d$d73$1@reader1.panix.com... >The Miller-Urey experiment... Underwater volcanic vents have been recognized as other abiotic (non-biological) chemical synthesis sites, where the active oxidizing agent is hot sulfur instead of oxygen.
Re: 200 meteorites on Earth traced to 5 craters on Mars
Author: "Jim Wilkins"
Date: Fri, 30 Aug 2024 13:34
Date: Fri, 30 Aug 2024 13:34
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"R Kym Horsell" wrote in message news:vasj6n$pgj$1@nnrp.usenet.blueworldhosting.com... THE FERMI PARADOX AND THE AURORA EFFECT: EXO-CIVILIZATION SETTLEMENT, EXPANSION AND STEADY STATES Carroll-Nellenback, Frank, Wright, Schart, 6 Feb 2020 We model the settlement of the galaxy by space-faring civilizations in order to address issues related to the Fermi Paradox. We are motivated to explore the problem in a way that avoids assumptions about the `agency' (i.e. questions of intent and motivation) of any exo-civilization seeking to settle other planetary systems. We begin by considering the speed of an advancing settlement front to determine if the galaxy can become inhabited with space-faring civilizations on timescales shorter than its age. Our models for the front speed include the directed settlement of nearby settleable systems through the launching of probes with a finite velocity and range. We also include the effect of stellar motions on the long term behavior of the settlement front which adds a diffusive component to its advance. As part of our model we also consider that only a fraction f of planets will have conditions ... --------------------------------- It's valid to define a search area by what is possible, but it dilutes the effort and still depends on unknowable assumptions such as how fast they can travel. In many cases scenarios of what is probable may be as or more productive. One is searching for wounded grazing vs predatory animals, some may run as far as they can but the dangerous ones tend to circle back and wait in ambush. The tactics to find them and live to tell about it are very different. North Sentinel island in the Andamans is a human example, it remains undisturbed because the natives are so hostile to outsiders. Earth might seem that way too. If I was from a species that had depleted its resources long ago I'd quarantine Earth for it's wasteful temptations. The Titanic remained lost for so long because of an invalid assumption that they reported their correct position. Their first report was too far west by 20 miles, the revised one by 13, possibly due to a temperature inversion mirage "haze" that obscured the western horizon, and the iceberg.
Re: 200 meteorites on Earth traced to 5 craters on Mars
Author: R Kym Horsell
Date: Fri, 30 Aug 2024 13:58
Date: Fri, 30 Aug 2024 13:58
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In alt.astronomy Jim Wilkins <muratlanne@gmail.com> wrote: > "danny burstein" wrote in message news:var74d$d73$1@reader1.panix.com... > >>The Miller-Urey experiment... > > Underwater volcanic vents have been recognized as other abiotic > (non-biological) chemical synthesis sites, where the active oxidizing agent > is hot sulfur instead of oxygen. > As one TV program put it -- they boiled and boiled various combinations of pre-biotic Earth ingredients since the 1950s and didnt seem to get past a mix of RNA components that most chemists characterise as "easy enough to sythesize with random reactions". Only in the past few years did anyone thing of alternating wet and dry conditions to get some polimerisation. But if you have made a bad assumption about where the chemsitry happened then you are not going to find the right conditions or evidence it ever happened the way you thought since some Haldane and some Russian in the 1920s. -- Surprising Findings in NASA's OSIRIS-REx Asteroid Sample: Could They Unlock the Origins of Life? SciTechDaily, 08 Jul 2024 12:39Z The most extreme life-forms in the universe New Scientist, 26 June 2008 There's hardly a niche on Earth that hasn't been colonised. Life can be found in scalding, acidic hot pools, in the driest deserts, and in ... THE FERMI PARADOX AND THE AURORA EFFECT: EXO-CIVILIZATION SETTLEMENT, EXPANSION AND STEADY STATES Carroll-Nellenback, Frank, Wright, Schart, 6 Feb 2020 We model the settlement of the galaxy by space-faring civilizations in order to address issues related to the Fermi Paradox. We are motivated to explore the problem in a way that avoids assumptions about the `agency' (i.e. questions of intent and motivation) of any exo-civilization seeking to settle other planetary systems. We begin by considering the speed of an advancing settlement front to determine if the galaxy can become inhabited with space-faring civilizations on timescales shorter than its age. Our models for the front speed include the directed settlement of nearby settleable systems through the launching of probes with a finite velocity and range. We also include the effect of stellar motions on the long term behavior of the settlement front which adds a diffusive component to its advance. As part of our model we also consider that only a fraction f of planets will have conditions ...
Re: 200 meteorites on Earth traced to 5 craters on Mars
Author: "Jim Wilkins"
Date: Fri, 30 Aug 2024 18:07
Date: Fri, 30 Aug 2024 18:07
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"R Kym Horsell" wrote in message news:vat20j$2u3p$1@nnrp.usenet.blueworldhosting.com... Many of these questions can be answered by game-theory simulations. I've done a few of them. Some of them based on first the Polynesian expansion across the Pacific (a good model for alien expansion as well ;) and then European colonialisation leads to some optimistic predictions for what anyone that maybe tarted out sailing from our galactic core 13 bn years ago. The general thrust seemed to be the early knocks they had encountering new system along the way as well as other travellers would smooth off a lot of the rough edges and they may be a lot more gentle and less gung-ho exploitative than when they may have started out. There was an old SF short story that proposed the same kind of pattern -- think it was called something like "gone fishin". ----------------------------------- Many advances have come from the bold imaginations of exceptional individuals, whose proposals have often been dismissed or ridiculed by "normal" people. I doubt that they would have been thought of or allowed to be added to computer models. Of course some have been spectacular failures, like the Franklin Expedition to find a Northwest Passage or Umberto Nobile's north pole flight in the airship "Italia". I stopped reading fiction when I discovered that autobiographies of clever and highly accomplished people could be more interesting.
Re: 200 meteorites on Earth traced to 5 craters on Mars
Author: R Kym Horsell
Date: Fri, 30 Aug 2024 18:11
Date: Fri, 30 Aug 2024 18:11
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In alt.astronomy Jim Wilkins <muratlanne@gmail.com> wrote: > "R Kym Horsell" wrote in message > news:vasj6n$pgj$1@nnrp.usenet.blueworldhosting.com... > > THE FERMI PARADOX AND THE AURORA EFFECT: EXO-CIVILIZATION SETTLEMENT, > EXPANSION > AND STEADY STATES > Carroll-Nellenback, Frank, Wright, Schart, 6 Feb 2020 > We model the settlement of the galaxy by space-faring civilizations in > order to address issues related to the Fermi Paradox. We are motivated > to explore the problem in a way that avoids assumptions about the `agency' > (i.e. questions of intent and motivation) of any exo-civilization > seeking to settle other planetary systems. We begin by considering the > speed of an advancing settlement front to determine if the galaxy can > become inhabited with space-faring civilizations on timescales shorter > than its age. Our models for the front speed include the directed > settlement of nearby settleable systems through the launching of > probes with a finite velocity and range. We also include the effect of > stellar motions on the long term behavior of the settlement front which > adds a diffusive component to its advance. As part of our model we also > consider that only a fraction f of planets will have conditions ... > > --------------------------------- > > It's valid to define a search area by what is possible, but it dilutes the > effort and still depends on unknowable assumptions such as how fast they can > travel. In many cases scenarios of what is probable may be as or more > productive. One is searching for wounded grazing vs predatory animals, some > may run as far as they can but the dangerous ones tend to circle back and > wait in ambush. The tactics to find them and live to tell about it are very > different. > > North Sentinel island in the Andamans is a human example, it remains > undisturbed because the natives are so hostile to outsiders. Earth might > seem that way too. If I was from a species that had depleted its resources > long ago I'd quarantine Earth for it's wasteful temptations. > > The Titanic remained lost for so long because of an invalid assumption that > they reported their correct position. Their first report was too far west by > 20 miles, the revised one by 13, possibly due to a temperature inversion > mirage "haze" that obscured the western horizon, and the iceberg. Many of these questions can be answered by game-theory simulations. I've done a few of them. Some of them based on first the Polynesian expansion across the Pacific (a good model for alien expansion as well ;) and then European colonialisation leads to some optimistic predictions for what anyone that maybe tarted out sailing from our galactic core 13 bn years ago. The general thrust seemed to be the early knocks they had encountering new system along the way as well as other travellers would smooth off a lot of the rough edges and they may be a lot more gentle and less gung-ho exploitative than when they may have started out. There was an old SF short story that proposed the same kind of pattern -- think it was called something like "gone fishin". -- [From the "get used to it" file:] -- <http://news.nationalgeographic.com/news/2013/13/ 130524-australia-extreme-weather-climate-change-heat-wave-science-world/> The rough-hewn sandstone buildings perched atop Observatory Hill have been keeping an eye on Sydney Harbor since 1858. They've pretty much seen it all-from the installation of the city's first gaslights to the construction of the now iconic Sydney Opera House and Harbor Bridge. But at 2:55 p.m. on January 18, 2013, meteorological equipment in the observatory registered something new: a read-out marking the hottest day in the city's history: 45.8?C (114.4?F). Sydney enjoys record spell of warm weather SMH, 19 Mar 2014 06:00Z With Wednesday's peak of 27.8 degrees, Sydney has now clocked daily maximums of at least 25 degrees for the past 17 days, eclipsing the previous record of 16 such days set in 1977, said Brett Dutschke, senior meteorologist with Weatherzone.
Re: 200 meteorites on Earth traced to 5 craters on Mars
Author: "Jim Wilkins"
Date: Sat, 31 Aug 2024 12:58
Date: Sat, 31 Aug 2024 12:58
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"Jim Wilkins" wrote in message news:vatft2$lo0b$1@dont-email.me... >Many advances have come from the bold imaginations of exceptional >individuals, whose proposals have often been dismissed or ridiculed by >"normal" people. ... Oliver Evans is a good example. https://en.wikipedia.org/wiki/Oliver_Evans
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