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Not that I get my science from SyFy but this particular hypothesis of a ice/dust composite doesn't survive the 'thermal / tidal' test. Which is that an object o

Not that I get my science from SyFy but this particular hypothesis of a ice/dust composite doesn't survive the 'thermal / tidal' test. Which is that an object of that density would deform due to the tidal forces imparted by the Sun as it changed direction. I've yet to see a paper that suggests its profile changed at all before, during, or after the solar system transit.

thebluehawk 8y ago
We didn't detect it until it was leaving. So we have no data to compare to in order to even begin to speculate if it changed shape at its periapsis.
joering2 8y ago
In Oumuamua defense, it hasn't seen this much of Sun to be impressed or inflicted by its thermal power. 25. kilometers. per. second. It went in and out before Sun could do its damage. However, the idea of a porous surface like a snowflake or sponge or something doesn't add up because of exact speed it travels. Even if this is just ice/dust composite, with that kind of speed, it would be disintegrated by having its surface polished with cosmic energy long before it could reach 25km/s. I hope we won't see another one. This one was so close to Earth it wasn't funny. And traveled so quick we wouldn't have time to call all family members to tell them we love them. Its nothing like meteor; even big one would just drop flat on earth, raise all dust for next 30,000 years, throw us back into stone age or close to extinction and some form of human life looking nothing like we do today would argue 250,000 years from now what caused the first human near-extinction. No. You're talking about razor-sharp thin and lightweight object traveling with insane speed. Upon impact, it would either penetrate Earth surface exploding inside the core, like any hollow bullet does, or it would cut Earth in half like a high power laser and deform itself on way out. Either way this wouldn't be your near extinction experience. This would be like all of sudden Earth spliced in half and both parts going away, while you are either being drown with oceans hundreds feet of water tall due to lack of gravity, or crushed by weight of same ocean who happened to froze in the upper atmosphere, caught some gravity and smashed on the top of you. I don't want to even think about super hot lava thrown everywhere without gravity it would be like spraying venom from a giant snake. I have no idea how something like that would look like when Earth split in two, and no movies of that kind of extinction has ever been done. But something tells me it would be far from an easy death and I would rather carry on suicide pill in my tooth like they did during WW2, rather than witness such literal Hell on Earth.
- saagarjha 8y ago
  > In Oumuamua defense, it hasn't seen this much of Sun to be impressed or inflicted by its thermal power. 25. kilometers. per. second. It went in and out before Sun could do its damage. …it was (and still will be) in the solar system for quite a while. The Solar System is big. > it would be disintegrated by having its surface polished with cosmic energy long before it could reach 25km/s …no? Relative to cosmic energy, it might as well be at rest. > Upon impact, it would either penetrate Earth surface exploding inside the core, like any hollow bullet does, or it would cut Earth in half like a high power laser and deform itself on way out. I suggest you read up on high velocity impacts: https://en.wikipedia.org/wiki/Impact_depth https://en.wikipedia.org/wiki/Impact_depth
  - joering2 8y ago
    I read it. It doesn't make a difference that majority of meteors burn in atmosphere and barely hit Earth surface. Oumuamua may have traveled through earth atmosphere and hit Earth undamaged. The difference is obviously like day and night.
    - saagarjha 8y ago
      This does not meaningfully change the result; as far as I'm aware you can just change the A/B ratio to account for the density of the atmosphere and treat it as any another layer. Even accounting for this, speed does not have a meaningful effect.
    - dragonwriter 8y ago
      > It doesn't make a difference that majority of meteors burn in atmosphere and barely hit Earth surface. Oumuamua may have traveled through earth atmosphere and hit Earth undamaged. The difference is obviously like day and night. https://en.m.wikipedia.org/wiki/Impact_event https://en.m.wikipedia.org/wiki/Impact_event Contains some tables with actual numbers (based on a 17km/s impact), including how big of a airburst a non-impacting object makes and how much of a crater an impacting object makes. You aren't splitting the Earth with something the size we are talking about with any of the estimates of it's size, even at 25km/s, which basically a little over doubles impact energy, the same as a 29% increase in diameter does.

thebluehawk 8y ago

We didn't detect it until it was leaving. So we have no data to compare to in order to even begin to speculate if it changed shape at its periapsis.

joering2 8y ago

In Oumuamua defense, it hasn't seen this much of Sun to be impressed or inflicted by its thermal power. 25. kilometers. per. second. It went in and out before Sun could do its damage. However, the idea of a porous surface like a snowflake or sponge or something doesn't add up because of exact speed it travels. Even if this is just ice/dust composite, with that kind of speed, it would be disintegrated by having its surface polished with cosmic energy long before it could reach 25km/s. I hope we won't see another one. This one was so close to Earth it wasn't funny. And traveled so quick we wouldn't have time to call all family members to tell them we love them. Its nothing like meteor; even big one would just drop flat on earth, raise all dust for next 30,000 years, throw us back into stone age or close to extinction and some form of human life looking nothing like we do today would argue 250,000 years from now what caused the first human near-extinction. No. You're talking about razor-sharp thin and lightweight object traveling with insane speed. Upon impact, it would either penetrate Earth surface exploding inside the core, like any hollow bullet does, or it would cut Earth in half like a high power laser and deform itself on way out. Either way this wouldn't be your near extinction experience. This would be like all of sudden Earth spliced in half and both parts going away, while you are either being drown with oceans hundreds feet of water tall due to lack of gravity, or crushed by weight of same ocean who happened to froze in the upper atmosphere, caught some gravity and smashed on the top of you. I don't want to even think about super hot lava thrown everywhere without gravity it would be like spraying venom from a giant snake. I have no idea how something like that would look like when Earth split in two, and no movies of that kind of extinction has ever been done. But something tells me it would be far from an easy death and I would rather carry on suicide pill in my tooth like they did during WW2, rather than witness such literal Hell on Earth.

saagarjha 8y ago
> In Oumuamua defense, it hasn't seen this much of Sun to be impressed or inflicted by its thermal power. 25. kilometers. per. second. It went in and out before Sun could do its damage. …it was (and still will be) in the solar system for quite a while. The Solar System is big. > it would be disintegrated by having its surface polished with cosmic energy long before it could reach 25km/s …no? Relative to cosmic energy, it might as well be at rest. > Upon impact, it would either penetrate Earth surface exploding inside the core, like any hollow bullet does, or it would cut Earth in half like a high power laser and deform itself on way out. I suggest you read up on high velocity impacts: https://en.wikipedia.org/wiki/Impact_depth https://en.wikipedia.org/wiki/Impact_depth
- joering2 8y ago
  I read it. It doesn't make a difference that majority of meteors burn in atmosphere and barely hit Earth surface. Oumuamua may have traveled through earth atmosphere and hit Earth undamaged. The difference is obviously like day and night.
  - saagarjha 8y ago
    This does not meaningfully change the result; as far as I'm aware you can just change the A/B ratio to account for the density of the atmosphere and treat it as any another layer. Even accounting for this, speed does not have a meaningful effect.
  - dragonwriter 8y ago
    > It doesn't make a difference that majority of meteors burn in atmosphere and barely hit Earth surface. Oumuamua may have traveled through earth atmosphere and hit Earth undamaged. The difference is obviously like day and night. https://en.m.wikipedia.org/wiki/Impact_event https://en.m.wikipedia.org/wiki/Impact_event Contains some tables with actual numbers (based on a 17km/s impact), including how big of a airburst a non-impacting object makes and how much of a crater an impacting object makes. You aren't splitting the Earth with something the size we are talking about with any of the estimates of it's size, even at 25km/s, which basically a little over doubles impact energy, the same as a 29% increase in diameter does.