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Survival Prepper
Survival Prepper  
1 y

SHOCKING! I Am TRULY WORRIED About The Warning That Was JUST ISSUED.. | My Personal Opinion
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SHOCKING! I Am TRULY WORRIED About The Warning That Was JUST ISSUED.. | My Personal Opinion

Hey yall! #themacs #breaking #news #prepping #elon #april #jamie #chase #survival #prepper #foodshortage #shtf Want More In-Depth Information For Colby Mac and The Mac';s?? Subscribe To His Weekly Newsletter where he goes into alot of personal views and thoughts https://themacs.substack.com/subscribe Check out a great place to purchase precious metals‚ Gold and Silver Genesis Gold Group | https://themacs.io/ 1-800-200-4653 | #1 Trusted Gold IRA Company Want Survival Prescriptions Antibiotics To Place In Your PREPPING Supply? Don';t be Caught OFF GUARD. Get Your antibiotics TODAY Jase Medical: http://jasemedical.com/themacs Water Storage Options: https://shrsl.com/3q133 Want Personalize Official T Shirts and MERCH of THE MAC';S Check out these Freedom LOVING Shirt designs https://www.bonfire.com/store/the-macs/ The Official Coffee Of The Mac';s ! Start Your Day Off Right! https://www.hollowpointcoffee.com/?ref=BOkwESDJ PRESERVE FOOD For 25-30 year SHELF LIFE: Harvest Right Freeze Dryers: https://affiliates.harvestright.com/1682.html Here is a link to our Amazon store (NO EXTRA COST TO YOU!!) of some of the items we use around the farm: http://www.amazon.com/shop/themacs Pressure Canning Your Gardens and Meat?? Check out FOR JARS CANNING LIDS https://forjars.co/?sca_ref=2329266.PdmQQljrOG HOSS TOOLS SEEDS- https://shrsl.com/3hk59 Dont Know what Seeds you NEED or want to start a garden?? NO WORRIES! Check out our Survival Seeds Heirloom Kits! This is a GAMECHANGER! https://survivalgardenseeds.com/?ref=THEMACS10 Worry about Food Sustainability??? Cant Grow Big Gardens or Raise your Own Meat??? Look at this link and prep with this! We Believe in being ready for ANYTHING https://mypatriotsupply.com/?rfsn=5889303.cc7234 Shop Azure Standard: https://www.azurestandard.com/?a_aid=7af267da7c Music Licensure Provided by Epidemic Sound We hope you enjoy our YouTube channel‚ please like‚ subscribe and share! Email: themacshappyhomestead@gmail.com ~happy homesteading yall~
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Survival Prepper
Survival Prepper  
1 y

Bushcraft Belt Rig for Scouting &;amp; Survival #survival
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Bushcraft Belt Rig for Scouting &;amp; Survival #survival

My latest belt kit. Full length video review coming to my channel! @ThePreparedWanderer
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Survival Prepper
Survival Prepper  
1 y

Bushcraft Belt Rig for Scouting &;amp; Survival #survival
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Bushcraft Belt Rig for Scouting &;amp; Survival #survival

My latest belt kit. Full length video review coming to my channel! @ThePreparedWanderer
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Survival Prepper
Survival Prepper  
1 y

Mistakes made at the Homestead.
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Mistakes made at the Homestead.

https://preppernurse1.com/ P.O. BOX 472 Cool Ridge W.V. 25825 preppernurse1@yahoo.com etsy.com/shop/MsCarswellsCreations Sharing some mistakes that happened at the Homestead.
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Survival Prepper
Survival Prepper  
1 y

Mistakes made at the Homestead.
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Mistakes made at the Homestead.

https://preppernurse1.com/ P.O. BOX 472 Cool Ridge W.V. 25825 preppernurse1@yahoo.com etsy.com/shop/MsCarswellsCreations Sharing some mistakes that happened at the Homestead.
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Survival Prepper
Survival Prepper  
1 y

Grocery Prices in Alaska are Freaking Nutz ! Get Prepared #swpg Stock Up with Freeze Dry Wholesalers
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Grocery Prices in Alaska are Freaking Nutz ! Get Prepared #swpg Stock Up with Freeze Dry Wholesalers

www.freezedrywholesalers.com 15% off all orders with code southwestprepper and Free shipping. @freezedrywholesalers2602 We thought it was expensive in the lower 48‚ holy crap ! Subscribe #swpg southwest prepper group Grocery Prices in Alaska are Freaking Nutz ! Get Prepared viral tiktok trending
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Survival Prepper
Survival Prepper  
1 y

Grocery Prices in Alaska are Freaking Nutz ! Get Prepared #swpg Stock Up with Freeze Dry Wholesalers
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Grocery Prices in Alaska are Freaking Nutz ! Get Prepared #swpg Stock Up with Freeze Dry Wholesalers

www.freezedrywholesalers.com 15% off all orders with code southwestprepper and Free shipping. @freezedrywholesalers2602 We thought it was expensive in the lower 48‚ holy crap ! Subscribe #swpg southwest prepper group Grocery Prices in Alaska are Freaking Nutz ! Get Prepared viral tiktok trending
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Science Explorer
Science Explorer
1 y

Did An Ancient Icy Impactor Create the Martian Moons?
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Did An Ancient Icy Impactor Create the Martian Moons?

The Martian moons Phobos and Deimos are oddballs. While other Solar System moons are round‚ Mars moons are misshapen and lumpy like potatoes. Theyre more like asteroids or other small bodies than moons. Because of their odd shapes and unusual compositions‚ scientists are still puzzling over their origins. Two main hypotheses attempt to explain Phobos and Deimos. One says theyre captured asteroids‚ and the other says they are debris from an ancient impactor that collided with Mars. Earths moon was likely formed by an ancient collision when a planetesimal slammed into Earth‚ so theres precedent for the impact hypothesis. Theres also precedent for the captured object scenario because scientists think some other Solar System moons‚ like Neptunes moon Triton‚ are captured objects. Phobos and Deimos have lots in common with carbonaceous C-type asteroids. Theyre the most plentiful type of asteroid in the Solar System‚ making up about 75% of the asteroid population. The moons compositions and albedos support the captured asteroid theory. But their orbits are circular and close to Mars equator. Captured objects should have much more eccentric orbits.This illustration shows Phobos and Deimos orbits along with the orbits of spacecraft at Mars. The moons near-circular orbits dont support the captured asteroid theory. Image Credit: By NASA/JPL-Caltech http://photojournal.jpl.nasa.gov/jpeg/PIA19396.jpg‚ Public Domain‚ https://commons.wikimedia.org/w/index.php?curid=39982795The moons are less dense than silicate‚ the most abundant material in Mars crust. That fact works against the impact theory. A powerful impact wouldve blasted material from Mars into space‚ forming a disk of material rotating around the planet. Phobos and Deimos wouldve formed from that material. If they result from an ancient planetesimal impact‚ they should contain more Martian silica. Heres the problem in a nutshell. The captured asteroid theory can explain the moons observed physical characteristics but not their orbits. The impact theory can explain their orbits but not their compositions. Phobos and Deimos look like potatoes more than moons. Image Credit: Left: By NASA / JPL-Caltech / University of Arizona http://photojournal.jpl.nasa.gov/catalog/PIA10368‚ Public Domain‚ https://commons.wikimedia.org/w/index.php?curid=5191977. Right: By NASA/JPL-Caltech/University of Arizona http://marsprogram.jpl.nasa.gov/mro/gallery/press/20090309a.html‚ Public Domain‚ https://commons.wikimedia.org/w/index.php?curid=6213773In research presented at the 55th Lunar and Planetary Science Conference‚ three researchers proposed a different origin story for Phobos and Deimos. They suggest that an impactor is responsible for creating the moons‚ but the impactor was icy.The research is titled THE ICY ORIGINS OF THE MARTIAN MOONS. The first author is Courteney Monchinski from the Earth-Life Science Institute at the Tokyo Institute of Technology.If a rocky impactor slammed into Mars‚ it wouldve created a massive debris disk around the planet. Previous researchers have examined the idea using simulations and found that an impact couldve created the moons. But the disk created by the impact wouldve been far more massive than Phobos and Deimos combined. The simulations showed that there wouldve been a third‚ much more massive moon created within Phobos orbit that wouldve fallen back down to Mars. But theres no strong evidence of something that massive striking Mars.This illustration shows how a giant impact couldve created Phobos and Deimos. The collision wouldve created a massive debris disk where a third more massive moon formed before falling back to Mars. Image Credit: Antony Trinh / Royal Observatory of BelgiumOther impact studies used basaltic impactors. But those showed that the temperature in the debris disk wouldve been so high it wouldve melted the disk material and destroyed ancient chondritic materials. Since the pair of moons appear to contain those materials‚ a basaltic impactor is ruled out. According to the research presented at the conference‚ an icy impactor can explain Phobos and Deimos origins. There are three reasons for that. The extra disk mass created by a rocky impactor would not be present. Instead‚ much of the mass in the impactor wouldve been vapourized on impact and escaped the system rather than persisting in the disk and being taken up by the formation of moons. There wouldve been no large third moon and no need to explain how it fell back to Mars.The second reason concerns the composition of the moons. With abundant water ice in the collision‚ the temperature in the debris disk wouldve been lower. That wouldve preserved the carbonaceous materials in Phobos and Deimos today. It also can help explain their density and possible porosity. An icy impactor couldve also delivered water to Mars‚ and we know Mars was wetter in its past. The third reason concerns Deimos orbit. Its not synchronous with Mars‚ and an icy impactor can explain that. With more water ice in the disk‚ there wouldve been a viscous interaction between the disks dust and vapour that extended the disk‚ allowing Deimos to occupy its orbit. The researchers used Smoothed Particle Hydrodynamic (SPH) simulations to test the icy impactor idea. They simulated giant impactors with varying quantities of water ice and watched as disks formed around Mars and moons formed in the disk. They first found that an impactor with any amount of water ice produced a more massive debris disk. It could be because an impactor containing water ice would be larger‚ though less massive‚ than one without any ice. That allowed more material to spray from the planet into the disk. It could also be because the water ice absorbs some of the impact energy when it vapourizes. That would cool the disk temperature‚ lowering the velocities of particles in the disk and making them less likely to escape. This figure from the research shows that any amount of ice in an impactor increases the size of the debris disk. Image Credit: Monchinski et al. 2024. LPSCVarying the ice content in the impactor also affected the makeup of the disk. Different amounts of ice lead to disks with different amounts of Martian rock and impactor rock in the disk. This graph from the study shows impactor ice content (x-axis) affects the debris disk composition. Image Credit: Monchinski et al. 2024. LPSCThe temperature in the disk is a critical part of this. Different amounts of water ice in the impactor change the disk temperature and what types of materials in the disk would melt. Impactors with more than 30% ice create disk temperatures too low to melt silicates. Perhaps more tellingly‚ impactors with more than 70% ice result in a disk temperature too low to alter or destroy chondritic material‚ which both Phobos and Deimos are expected to contain. According to the researchers‚ an icy impactor can also explain other features. The existence of water in the impact-generated disk also suggests that water may condense‚ accounting for the possible water-ice content of the moons‚ they write. Ultimately‚ the researchers say an icy impactor with 70% to 90% water ice mantles can explain the pair of moons. The best case for reproducing the moons proposed compositions are the 70% and 90% water-ice mantle impactor cases‚ as they allow for low disk temperatures and more chances for chondritic materials to survive‚ they explain. Unfortunately‚ that may not be realistic. In our current solar system‚ an object with around 70% or 90% water-ice content is not exactly realistic‚ as the object with the highest amount of water content in our current solar system‚ Ganymede‚ is only about 50% water‚ they write.The ESAs Mars Express orbiter captured this image of Phobos over the Martian landscape in this image taken in November 2010. Irregularly shaped and only 27 km long‚ Phobos is actually much darker (due to its carbon-rich surface) than is apparent in this contrast-enhanced view. Image Credit: ESA / DLR / G. neukumBut could things have been different in the past? Samples from asteroid Ryugu suggest that its parent body couldve been up to 90% water. That number is based on the types of minerals in Ryugu. But unfortunately‚ scientists dont now for sure. Ryugus parent body could have contained as little as 20% water. But its at least plausible that early in the Solar Systems life‚ an impactor with 70% water ice could have existed. If so‚ then the icy impactor scenario could be a robust theory to explain the origins of Phobos and Deimos. This impactor would have come from the outer solar system around the time of giant planet instability‚ the authors write. During that time‚ outer Solar System bodies were perturbed and sent flying into the inner Solar System. But in this case‚ the impacts timing needs to be constrained by Phobos and Deimos formation ages.Scientists need more evidence to deepen their understanding of Mars and its moons. Japans Martian Moons eXploration (MMX) mission will provide that. MMXs mission is to return a sample of Phobos to Earth. The goal is to determine if it is a captured asteroid or the result of an impact. Unfortunately‚ JAXA just delayed MMXs launch. It was scheduled to launch in September 2024 but has been delayed until 2026. That means we wont get samples until 2031 instead of 2029. JAXA has completed successful sample return missions‚ so they have the expertise to bring a piece of Phobos back to Earth. If scientists can determine how Phobos and Deimos formed‚ itll be part of a much larger‚ detailed picture of how the Solar System formed. Itll be worth it if we have to wait a couple extra years. The post Did An Ancient Icy Impactor Create the Martian Moons? appeared first on Universe Today.
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Science Explorer
Science Explorer
1 y

Did An Ancient Icy Impactor Create the Martian Moons?
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Did An Ancient Icy Impactor Create the Martian Moons?

The Martian moons Phobos and Deimos are oddballs. While other Solar System moons are round‚ Mars moons are misshapen and lumpy like potatoes. Theyre more like asteroids or other small bodies than moons. Because of their odd shapes and unusual compositions‚ scientists are still puzzling over their origins. Two main hypotheses attempt to explain Phobos and Deimos. One says theyre captured asteroids‚ and the other says they are debris from an ancient impactor that collided with Mars. Earths moon was likely formed by an ancient collision when a planetesimal slammed into Earth‚ so theres precedent for the impact hypothesis. Theres also precedent for the captured object scenario because scientists think some other Solar System moons‚ like Neptunes moon Triton‚ are captured objects. Phobos and Deimos have lots in common with carbonaceous C-type asteroids. Theyre the most plentiful type of asteroid in the Solar System‚ making up about 75% of the asteroid population. The moons compositions and albedos support the captured asteroid theory. But their orbits are circular and close to Mars equator. Captured objects should have much more eccentric orbits.This illustration shows Phobos and Deimos orbits along with the orbits of spacecraft at Mars. The moons near-circular orbits dont support the captured asteroid theory. Image Credit: By NASA/JPL-Caltech http://photojournal.jpl.nasa.gov/jpeg/PIA19396.jpg‚ Public Domain‚ https://commons.wikimedia.org/w/index.php?curid=39982795The moons are less dense than silicate‚ the most abundant material in Mars crust. That fact works against the impact theory. A powerful impact wouldve blasted material from Mars into space‚ forming a disk of material rotating around the planet. Phobos and Deimos wouldve formed from that material. If they result from an ancient planetesimal impact‚ they should contain more Martian silica. Heres the problem in a nutshell. The captured asteroid theory can explain the moons observed physical characteristics but not their orbits. The impact theory can explain their orbits but not their compositions. Phobos and Deimos look like potatoes more than moons. Image Credit: Left: By NASA / JPL-Caltech / University of Arizona http://photojournal.jpl.nasa.gov/catalog/PIA10368‚ Public Domain‚ https://commons.wikimedia.org/w/index.php?curid=5191977. Right: By NASA/JPL-Caltech/University of Arizona http://marsprogram.jpl.nasa.gov/mro/gallery/press/20090309a.html‚ Public Domain‚ https://commons.wikimedia.org/w/index.php?curid=6213773In research presented at the 55th Lunar and Planetary Science Conference‚ three researchers proposed a different origin story for Phobos and Deimos. They suggest that an impactor is responsible for creating the moons‚ but the impactor was icy.The research is titled THE ICY ORIGINS OF THE MARTIAN MOONS. The first author is Courteney Monchinski from the Earth-Life Science Institute at the Tokyo Institute of Technology.If a rocky impactor slammed into Mars‚ it wouldve created a massive debris disk around the planet. Previous researchers have examined the idea using simulations and found that an impact couldve created the moons. But the disk created by the impact wouldve been far more massive than Phobos and Deimos combined. The simulations showed that there wouldve been a third‚ much more massive moon created within Phobos orbit that wouldve fallen back down to Mars. But theres no strong evidence of something that massive striking Mars.This illustration shows how a giant impact couldve created Phobos and Deimos. The collision wouldve created a massive debris disk where a third more massive moon formed before falling back to Mars. Image Credit: Antony Trinh / Royal Observatory of BelgiumOther impact studies used basaltic impactors. But those showed that the temperature in the debris disk wouldve been so high it wouldve melted the disk material and destroyed ancient chondritic materials. Since the pair of moons appear to contain those materials‚ a basaltic impactor is ruled out. According to the research presented at the conference‚ an icy impactor can explain Phobos and Deimos origins. There are three reasons for that. The extra disk mass created by a rocky impactor would not be present. Instead‚ much of the mass in the impactor wouldve been vapourized on impact and escaped the system rather than persisting in the disk and being taken up by the formation of moons. There wouldve been no large third moon and no need to explain how it fell back to Mars.The second reason concerns the composition of the moons. With abundant water ice in the collision‚ the temperature in the debris disk wouldve been lower. That wouldve preserved the carbonaceous materials in Phobos and Deimos today. It also can help explain their density and possible porosity. An icy impactor couldve also delivered water to Mars‚ and we know Mars was wetter in its past. The third reason concerns Deimos orbit. Its not synchronous with Mars‚ and an icy impactor can explain that. With more water ice in the disk‚ there wouldve been a viscous interaction between the disks dust and vapour that extended the disk‚ allowing Deimos to occupy its orbit. The researchers used Smoothed Particle Hydrodynamic (SPH) simulations to test the icy impactor idea. They simulated giant impactors with varying quantities of water ice and watched as disks formed around Mars and moons formed in the disk. They first found that an impactor with any amount of water ice produced a more massive debris disk. It could be because an impactor containing water ice would be larger‚ though less massive‚ than one without any ice. That allowed more material to spray from the planet into the disk. It could also be because the water ice absorbs some of the impact energy when it vapourizes. That would cool the disk temperature‚ lowering the velocities of particles in the disk and making them less likely to escape. This figure from the research shows that any amount of ice in an impactor increases the size of the debris disk. Image Credit: Monchinski et al. 2024. LPSCVarying the ice content in the impactor also affected the makeup of the disk. Different amounts of ice lead to disks with different amounts of Martian rock and impactor rock in the disk. This graph from the study shows impactor ice content (x-axis) affects the debris disk composition. Image Credit: Monchinski et al. 2024. LPSCThe temperature in the disk is a critical part of this. Different amounts of water ice in the impactor change the disk temperature and what types of materials in the disk would melt. Impactors with more than 30% ice create disk temperatures too low to melt silicates. Perhaps more tellingly‚ impactors with more than 70% ice result in a disk temperature too low to alter or destroy chondritic material‚ which both Phobos and Deimos are expected to contain. According to the researchers‚ an icy impactor can also explain other features. The existence of water in the impact-generated disk also suggests that water may condense‚ accounting for the possible water-ice content of the moons‚ they write. Ultimately‚ the researchers say an icy impactor with 70% to 90% water ice mantles can explain the pair of moons. The best case for reproducing the moons proposed compositions are the 70% and 90% water-ice mantle impactor cases‚ as they allow for low disk temperatures and more chances for chondritic materials to survive‚ they explain. Unfortunately‚ that may not be realistic. In our current solar system‚ an object with around 70% or 90% water-ice content is not exactly realistic‚ as the object with the highest amount of water content in our current solar system‚ Ganymede‚ is only about 50% water‚ they write.The ESAs Mars Express orbiter captured this image of Phobos over the Martian landscape in this image taken in November 2010. Irregularly shaped and only 27 km long‚ Phobos is actually much darker (due to its carbon-rich surface) than is apparent in this contrast-enhanced view. Image Credit: ESA / DLR / G. neukumBut could things have been different in the past? Samples from asteroid Ryugu suggest that its parent body couldve been up to 90% water. That number is based on the types of minerals in Ryugu. But unfortunately‚ scientists dont now for sure. Ryugus parent body could have contained as little as 20% water. But its at least plausible that early in the Solar Systems life‚ an impactor with 70% water ice could have existed. If so‚ then the icy impactor scenario could be a robust theory to explain the origins of Phobos and Deimos. This impactor would have come from the outer solar system around the time of giant planet instability‚ the authors write. During that time‚ outer Solar System bodies were perturbed and sent flying into the inner Solar System. But in this case‚ the impacts timing needs to be constrained by Phobos and Deimos formation ages.Scientists need more evidence to deepen their understanding of Mars and its moons. Japans Martian Moons eXploration (MMX) mission will provide that. MMXs mission is to return a sample of Phobos to Earth. The goal is to determine if it is a captured asteroid or the result of an impact. Unfortunately‚ JAXA just delayed MMXs launch. It was scheduled to launch in September 2024 but has been delayed until 2026. That means we wont get samples until 2031 instead of 2029. JAXA has completed successful sample return missions‚ so they have the expertise to bring a piece of Phobos back to Earth. If scientists can determine how Phobos and Deimos formed‚ itll be part of a much larger‚ detailed picture of how the Solar System formed. Itll be worth it if we have to wait a couple extra years. The post Did An Ancient Icy Impactor Create the Martian Moons? appeared first on Universe Today.
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Science Explorer
Science Explorer
1 y

Did An Ancient Icy Impactor Create the Martian Moons?
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Did An Ancient Icy Impactor Create the Martian Moons?

The Martian moons Phobos and Deimos are oddballs. While other Solar System moons are round‚ Mars moons are misshapen and lumpy like potatoes. Theyre more like asteroids or other small bodies than moons. Because of their odd shapes and unusual compositions‚ scientists are still puzzling over their origins. Two main hypotheses attempt to explain Phobos and Deimos. One says theyre captured asteroids‚ and the other says they are debris from an ancient impactor that collided with Mars. Earths moon was likely formed by an ancient collision when a planetesimal slammed into Earth‚ so theres precedent for the impact hypothesis. Theres also precedent for the captured object scenario because scientists think some other Solar System moons‚ like Neptunes moon Triton‚ are captured objects. Phobos and Deimos have lots in common with carbonaceous C-type asteroids. Theyre the most plentiful type of asteroid in the Solar System‚ making up about 75% of the asteroid population. The moons compositions and albedos support the captured asteroid theory. But their orbits are circular and close to Mars equator. Captured objects should have much more eccentric orbits.This illustration shows Phobos and Deimos orbits along with the orbits of spacecraft at Mars. The moons near-circular orbits dont support the captured asteroid theory. Image Credit: By NASA/JPL-Caltech http://photojournal.jpl.nasa.gov/jpeg/PIA19396.jpg‚ Public Domain‚ https://commons.wikimedia.org/w/index.php?curid=39982795The moons are less dense than silicate‚ the most abundant material in Mars crust. That fact works against the impact theory. A powerful impact wouldve blasted material from Mars into space‚ forming a disk of material rotating around the planet. Phobos and Deimos wouldve formed from that material. If they result from an ancient planetesimal impact‚ they should contain more Martian silica. Heres the problem in a nutshell. The captured asteroid theory can explain the moons observed physical characteristics but not their orbits. The impact theory can explain their orbits but not their compositions. Phobos and Deimos look like potatoes more than moons. Image Credit: Left: By NASA / JPL-Caltech / University of Arizona http://photojournal.jpl.nasa.gov/catalog/PIA10368‚ Public Domain‚ https://commons.wikimedia.org/w/index.php?curid=5191977. Right: By NASA/JPL-Caltech/University of Arizona http://marsprogram.jpl.nasa.gov/mro/gallery/press/20090309a.html‚ Public Domain‚ https://commons.wikimedia.org/w/index.php?curid=6213773In research presented at the 55th Lunar and Planetary Science Conference‚ three researchers proposed a different origin story for Phobos and Deimos. They suggest that an impactor is responsible for creating the moons‚ but the impactor was icy.The research is titled THE ICY ORIGINS OF THE MARTIAN MOONS. The first author is Courteney Monchinski from the Earth-Life Science Institute at the Tokyo Institute of Technology.If a rocky impactor slammed into Mars‚ it wouldve created a massive debris disk around the planet. Previous researchers have examined the idea using simulations and found that an impact couldve created the moons. But the disk created by the impact wouldve been far more massive than Phobos and Deimos combined. The simulations showed that there wouldve been a third‚ much more massive moon created within Phobos orbit that wouldve fallen back down to Mars. But theres no strong evidence of something that massive striking Mars.This illustration shows how a giant impact couldve created Phobos and Deimos. The collision wouldve created a massive debris disk where a third more massive moon formed before falling back to Mars. Image Credit: Antony Trinh / Royal Observatory of BelgiumOther impact studies used basaltic impactors. But those showed that the temperature in the debris disk wouldve been so high it wouldve melted the disk material and destroyed ancient chondritic materials. Since the pair of moons appear to contain those materials‚ a basaltic impactor is ruled out. According to the research presented at the conference‚ an icy impactor can explain Phobos and Deimos origins. There are three reasons for that. The extra disk mass created by a rocky impactor would not be present. Instead‚ much of the mass in the impactor wouldve been vapourized on impact and escaped the system rather than persisting in the disk and being taken up by the formation of moons. There wouldve been no large third moon and no need to explain how it fell back to Mars.The second reason concerns the composition of the moons. With abundant water ice in the collision‚ the temperature in the debris disk wouldve been lower. That wouldve preserved the carbonaceous materials in Phobos and Deimos today. It also can help explain their density and possible porosity. An icy impactor couldve also delivered water to Mars‚ and we know Mars was wetter in its past. The third reason concerns Deimos orbit. Its not synchronous with Mars‚ and an icy impactor can explain that. With more water ice in the disk‚ there wouldve been a viscous interaction between the disks dust and vapour that extended the disk‚ allowing Deimos to occupy its orbit. The researchers used Smoothed Particle Hydrodynamic (SPH) simulations to test the icy impactor idea. They simulated giant impactors with varying quantities of water ice and watched as disks formed around Mars and moons formed in the disk. They first found that an impactor with any amount of water ice produced a more massive debris disk. It could be because an impactor containing water ice would be larger‚ though less massive‚ than one without any ice. That allowed more material to spray from the planet into the disk. It could also be because the water ice absorbs some of the impact energy when it vapourizes. That would cool the disk temperature‚ lowering the velocities of particles in the disk and making them less likely to escape. This figure from the research shows that any amount of ice in an impactor increases the size of the debris disk. Image Credit: Monchinski et al. 2024. LPSCVarying the ice content in the impactor also affected the makeup of the disk. Different amounts of ice lead to disks with different amounts of Martian rock and impactor rock in the disk. This graph from the study shows impactor ice content (x-axis) affects the debris disk composition. Image Credit: Monchinski et al. 2024. LPSCThe temperature in the disk is a critical part of this. Different amounts of water ice in the impactor change the disk temperature and what types of materials in the disk would melt. Impactors with more than 30% ice create disk temperatures too low to melt silicates. Perhaps more tellingly‚ impactors with more than 70% ice result in a disk temperature too low to alter or destroy chondritic material‚ which both Phobos and Deimos are expected to contain. According to the researchers‚ an icy impactor can also explain other features. The existence of water in the impact-generated disk also suggests that water may condense‚ accounting for the possible water-ice content of the moons‚ they write. Ultimately‚ the researchers say an icy impactor with 70% to 90% water ice mantles can explain the pair of moons. The best case for reproducing the moons proposed compositions are the 70% and 90% water-ice mantle impactor cases‚ as they allow for low disk temperatures and more chances for chondritic materials to survive‚ they explain. Unfortunately‚ that may not be realistic. In our current solar system‚ an object with around 70% or 90% water-ice content is not exactly realistic‚ as the object with the highest amount of water content in our current solar system‚ Ganymede‚ is only about 50% water‚ they write.The ESAs Mars Express orbiter captured this image of Phobos over the Martian landscape in this image taken in November 2010. Irregularly shaped and only 27 km long‚ Phobos is actually much darker (due to its carbon-rich surface) than is apparent in this contrast-enhanced view. Image Credit: ESA / DLR / G. neukumBut could things have been different in the past? Samples from asteroid Ryugu suggest that its parent body couldve been up to 90% water. That number is based on the types of minerals in Ryugu. But unfortunately‚ scientists dont now for sure. Ryugus parent body could have contained as little as 20% water. But its at least plausible that early in the Solar Systems life‚ an impactor with 70% water ice could have existed. If so‚ then the icy impactor scenario could be a robust theory to explain the origins of Phobos and Deimos. This impactor would have come from the outer solar system around the time of giant planet instability‚ the authors write. During that time‚ outer Solar System bodies were perturbed and sent flying into the inner Solar System. But in this case‚ the impacts timing needs to be constrained by Phobos and Deimos formation ages.Scientists need more evidence to deepen their understanding of Mars and its moons. Japans Martian Moons eXploration (MMX) mission will provide that. MMXs mission is to return a sample of Phobos to Earth. The goal is to determine if it is a captured asteroid or the result of an impact. Unfortunately‚ JAXA just delayed MMXs launch. It was scheduled to launch in September 2024 but has been delayed until 2026. That means we wont get samples until 2031 instead of 2029. JAXA has completed successful sample return missions‚ so they have the expertise to bring a piece of Phobos back to Earth. If scientists can determine how Phobos and Deimos formed‚ itll be part of a much larger‚ detailed picture of how the Solar System formed. Itll be worth it if we have to wait a couple extra years. The post Did An Ancient Icy Impactor Create the Martian Moons? appeared first on Universe Today.
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