Unsurprisingly, you failed to mention the criticism Bergner & Seligman received. "Bergner and Seligman (hereafter BS23) proposed that evaporation of trapped H2 created by cosmic rays (CRs) can explain the non-gravitational acceleration. However, their modeling of the thermal structure of 1I/`Oumuamua ignored the crucial cooling effect of evaporating H2. By taking into account the cooling by H2 evaporation, we show that the surface temperature of H2-water ice is a factor of 9 lower than the case without evaporative cooling. As a result, the thermal speed of outgassing H2 is decreased by a factor of 3. Our one-dimensional thermal modeling that takes into account evaporative cooling for two chosen values of thermal conductivity of κ=0.01 and 0.1 WK−1m−1 shows that the water ice volume available for H2 sublimation at T>30 K would be reduced by a factor of 9 and 5 compared to the results of BS23, not enabling enough hydrogen to propel 1I/`Oumuamua." Implications of evaporative cooling by H2 for 1I/`Oumuamua Thiem Hoang, Abraham Loeb The fact is, that we don't know what caused the non-gravitational acceleration. Radiation pressure is certainly one plausible explanation. Claiming that it is not, without any evidence backing up that claim... well, sounds more like a religious dogma rather than scientific estimation to me. (And btw, Hainauts comments in regards to this were just stupid.)
Thanks so much for saving me 1 hour of my life watching this video 👍 Without contradictory it is not science but speeches at the bar! Shame of humanity!
Thanks for saving me an hour as well. I have better things to do than listen to a bunch of possibility-denialists invent unproven and undiscovered excuses for not accepting the _mere possibility_ of alien manufacture even when exactly such a technology is literally on our own damned drawing boards. That type of denialist consistently operates under the artificial and unspoken constraint that aliens are scientifically acceptable so long as they're far away and/or long in the past, and under the chauvinism that we will discover and surveil other species who themselves have not discovered and surveilled us first. SETI has always been a mediocre organization and has generated almost nothing in its decades of funding. Too bad, since they and "ufology" should be looking for the same alien peoples.
"Implications of Evaporative Cooling by H2 for 1I/‘Oumuamua" by Hoang and Loeb was published on July 10 and accepted on June 18. Comment from our speakers: The new paper is considering chemical cooling, but there are additional chemical heat sources that are not considered. For instance, the crystallization of H2O is exothermic, and a back-of-the-envelope calculation shows that it should more than compensate for the heat loss from sublimation. My 2c: The study by Hoang and Loeb doesn't provide an incomplete and detailed analysis, sublimation cooling is not an issue. Great that people are working on this in any case.
@@AllPlanets My comment was not so much about who is right and who is wrong. I did not like the bias and dishonesty implied by the fact that critique was not even mentioned. I agree that it's great people are working on this. I hope they'll leave the childish games and shaming the opponents to teenagers and focus on their work instead.
These SETI mediocrities truly don't know what they believe. There's a speech from a few years back where Seth Sleestak effectively uses a "pioneer ants on the countertop" analogy, and then less than two minutes later dismisses the implicit (unnamed) possibility of alien species sending exactly such pioneer "ants" to earth. That such people are considered "scientists" boggles my mind.
No. But that doesn't mean he was right either. His theory is still valid, but the burden of proof is very high. What Loeb suggested remains perfectly valid. Loeb's view is that his theory is worth exploring because the possibility it is correct is so important it should not be ignored. Who can disagree?
I'm no physicist, but it seems reasonable that its inbound deceleration would be the same as its outbound acceleration. The charts I've seen show the same speed at the same distances on each side, though I can't guarantee that equal deceleration was factored in. If not, would it be enough to change the assumed originating speed of "local standard of rest" to something else?
@@VaraLaFey The reason I would like to know this, is it would or may prove if it had an intelligences behind it, if it was shown the thrust was there before moving past the sun. I wonder if any other observatory had picked it up long before...
@@hardergamer Not sure I understand. Do you wonder if they slowed down just for us on the inbound trajectory? That would imply they will speed up after leaving our observation range on their outbound trajectory. Likely I misunderstand you, but I've half-jokingly thought that Starshot or similar lightsail will eventually catch up to where Mua should be, and it won't be there. 🙂
Everyone wants their theory to be the most accepted. There is no direct evidence of H2 outgassing it is just theoretical model and but they are quick to debunk other ideas. The fact is there is no clear explanation of acceleration and simplest answer is "we don't know".
Worse than no evidence, if the hydrogen was being held in a water ice lattace, it seems unlikely a significant % of mass of the object could boil off a spinning object, for the outgassing not to change the spin and also so little of the water to escape that it couldn't be detected.
That’s not the way science works. Scientists don’t give a damn about the acceptance of « their theory » . They care in finding answers which are simple, elegant and does not involved divinities or aliens if possible. The H2 production was discussed in a paper published in the 1980s first but was quickly forbidden because scientists didn’t see its use. ‘Oumuamua has revived this exotic and forgotten physics. Nobody is getting a raise for that, it’s just a small brick added in our knowledge on how the universe works. Thanks for not thinking that we are all driven by ego and money like politicians or rock stars. People are better than that.
@@AllPlanets "...and does not involved divinities or aliens if possible..." Why? The fact remains that you didn't get Avi Loeb or Thiem Hoang talking in this live! Why?
Because they are massive (this was one of my questions). Oumuamua was only 100s m in diameter , long period comets are 5-50 km in diameter so the H2 evaporation does not have a strong effect.
If we in for example 100-200 years have invented and perfected some new advanced propulsion system, do we know the orbit of Oumuamua exiting the solar system well enough to catch up to it and find it again?
"it could be a comet after all"; blithering nonsense! No matter how you look at it, it does not meet any of the accepted criteria for being called a "comet". Can nobody accept that we simply don't know? Is saying we don't know what it is that terrifying?
It could be an extremely unlikely comet. Yes it's far more lightly to be a thin sheet of material formed by unknown processes. But I agree this theory about a significant % of the mass of this object being hydrogen gas that has magically been trapped by water ice that also magically didn't also didn't include this water in the outgassing and also magically didn't adjust the spin while outgassing is extremely unlikely. We will know more when lots of interstellar objects are discovered.
It seems to me that we have no problem in saying "we don't know" in most cases. However, when it comes to possibility of artifacts of an extraterrestrial technological civilization (ETC), then we always know for sure: We know that ETC does not exists, and if they do, they're definitely not close by, or if they are close by, they wouldn't send probes here because we're uninteresting, and even if they would, god forbid, consider us mildly interesting, they couldn't possibly send interstellar probes because of the speed limit. And on and on and on and on ad nauseam. The bottom line is, that we ALWAYS KNOW FOR SURE it's not ETC. And how do we know this? It's simple. It's not ETC because it cannot be ETC. And because of that, we do not need... No, we must crush, ridicule and ostracize everybody who dares to even consider such a possibility. More seriously speaking, the same arrogant "we know it all" attitude is quite common in many fields of science. I think science in general is quite well protected against bogus claims, but not so well protected against various sociological phenomena producing bad incentives and amplifying cognitive biases (group-think and taboo subjects are two examples of this). Besides that, scientist are human after all. There are always jerks who think it's perfectly fine to ridicule everyone who happens to disagree with them. Especially if someone suggests anything outside of the main-stream "party line".
What is happening with oxygen during long period changes resulting in and from multi-form change of water ice with liberation/sublimation/squeezing out of hydrogen?
Well, look at the authors. What do you expect from outreach/extension classes? That guy Seti, Sthi, _- he's not a disappointment - not really.. but then, what will we know is when we see one?
@@SETIInstituteI love how convinced you all are that there is nothing left to know concerning this object. The schadenfreude will be that much sweeter when you are proved wrong. 💫🙏🍻
Unsurprisingly, you failed to mention the criticism Bergner & Seligman received.
"Bergner and Seligman (hereafter BS23) proposed that evaporation of trapped H2 created by cosmic rays (CRs) can explain the non-gravitational acceleration. However, their modeling of the thermal structure of 1I/`Oumuamua ignored the crucial cooling effect of evaporating H2. By taking into account the cooling by H2 evaporation, we show that the surface temperature of H2-water ice is a factor of 9 lower than the case without evaporative cooling. As a result, the thermal speed of outgassing H2 is decreased by a factor of 3. Our one-dimensional thermal modeling that takes into account evaporative cooling for two chosen values of thermal conductivity of κ=0.01 and 0.1 WK−1m−1 shows that the water ice volume available for H2 sublimation at T>30 K would be reduced by a factor of 9 and 5 compared to the results of BS23, not enabling enough hydrogen to propel 1I/`Oumuamua."
Implications of evaporative cooling by H2 for 1I/`Oumuamua
Thiem Hoang, Abraham Loeb
The fact is, that we don't know what caused the non-gravitational acceleration. Radiation pressure is certainly one plausible explanation. Claiming that it is not, without any evidence backing up that claim... well, sounds more like a religious dogma rather than scientific estimation to me. (And btw, Hainauts comments in regards to this were just stupid.)
Thanks so much for saving me 1 hour of my life watching this video 👍
Without contradictory it is not science but speeches at the bar! Shame of humanity!
Thanks for saving me an hour as well. I have better things to do than listen to a bunch of possibility-denialists invent unproven and undiscovered excuses for not accepting the _mere possibility_ of alien manufacture even when exactly such a technology is literally on our own damned drawing boards. That type of denialist consistently operates under the artificial and unspoken constraint that aliens are scientifically acceptable so long as they're far away and/or long in the past, and under the chauvinism that we will discover and surveil other species who themselves have not discovered and surveilled us first. SETI has always been a mediocre organization and has generated almost nothing in its decades of funding. Too bad, since they and "ufology" should be looking for the same alien peoples.
I just smoked the biggest blunt of my life. FYI.
"Implications of Evaporative Cooling by H2 for 1I/‘Oumuamua" by Hoang and Loeb was published on July 10 and accepted on June 18.
Comment from our speakers: The new paper is considering chemical cooling, but there are additional chemical heat sources that are not considered. For instance, the crystallization of H2O is exothermic, and a back-of-the-envelope calculation shows that it should more than compensate for the heat loss from sublimation.
My 2c: The study by Hoang and Loeb doesn't provide an incomplete and detailed analysis, sublimation cooling is not an issue. Great that people are working on this in any case.
@@AllPlanets My comment was not so much about who is right and who is wrong. I did not like the bias and dishonesty implied by the fact that critique was not even mentioned.
I agree that it's great people are working on this. I hope they'll leave the childish games and shaming the opponents to teenagers and focus on their work instead.
Didn't Avi Loeb debunk this explanation of its acceleration the day it was published?
Hainaut: we know everything we need to know about this object
(5 minutes later) Hainaut: we don't know how this object got its shape
FAIL
These SETI mediocrities truly don't know what they believe. There's a speech from a few years back where Seth Sleestak effectively uses a "pioneer ants on the countertop" analogy, and then less than two minutes later dismisses the implicit (unnamed) possibility of alien species sending exactly such pioneer "ants" to earth. That such people are considered "scientists" boggles my mind.
so Avi Loeb was wrong?
No. But that doesn't mean he was right either. His theory is still valid, but the burden of proof is very high.
What Loeb suggested remains perfectly valid. Loeb's view is that his theory is worth exploring because the possibility it is correct is so important it should not be ignored. Who can disagree?
Surely, this was a fragment from a catastrophic event?
He usually is
Avi loeb hijacked science and manipulated it for personal gain/fame.
He’s a sociopath (read his book, )
Some theories are more plausible than others. Any theory about ʻOumuamua is untestable, including Mr. Loeb's.
4:00 Ort Cloud: Does any one know how long it will be before Oumuamua begins to enter the Ort Cloud??
How much did Oumuamua decelerate as it was moving towards the sun after deducting the sun's gravitational pull? Or did we not see it in time?
ʻOumuamua discovered when it was outbound from the solar system. There were no observations of it inbound.
I'm no physicist, but it seems reasonable that its inbound deceleration would be the same as its outbound acceleration. The charts I've seen show the same speed at the same distances on each side, though I can't guarantee that equal deceleration was factored in. If not, would it be enough to change the assumed originating speed of "local standard of rest" to something else?
@@VaraLaFey The reason I would like to know this, is it would or may prove if it had an intelligences behind it, if it was shown the thrust was there before moving past the sun. I wonder if any other observatory had picked it up long before...
@@hardergamer Not sure I understand. Do you wonder if they slowed down just for us on the inbound trajectory? That would imply they will speed up after leaving our observation range on their outbound trajectory.
Likely I misunderstand you, but I've half-jokingly thought that Starshot or similar lightsail will eventually catch up to where Mua should be, and it won't be there. 🙂
Everyone wants their theory to be the most accepted. There is no direct evidence of H2 outgassing it is just theoretical model and but they are quick to debunk other ideas. The fact is there is no clear explanation of acceleration and simplest answer is "we don't know".
Worse than no evidence, if the hydrogen was being held in a water ice lattace, it seems unlikely a significant % of mass of the object could boil off a spinning object, for the outgassing not to change the spin and also so little of the water to escape that it couldn't be detected.
That’s not the way science works. Scientists don’t give a damn about the acceptance of « their theory » . They care in finding answers which are simple, elegant and does not involved divinities or aliens if possible. The H2 production was discussed in a paper published in the 1980s first but was quickly forbidden because scientists didn’t see its use. ‘Oumuamua has revived this exotic and forgotten physics. Nobody is getting a raise for that, it’s just a small brick added in our knowledge on how the universe works. Thanks for not thinking that we are all driven by ego and money like politicians or rock stars. People are better than that.
@@AllPlanets "...and does not involved divinities or aliens if possible..." Why?
The fact remains that you didn't get Avi Loeb or Thiem Hoang talking
in this live! Why?
Thank you for the best talk on this subject.
Our pleasure!
Great content
Was evaporation of trapped H2 ever observed in any of our own comets?
If not than this explanation makes no sense
Because they are massive (this was one of my questions). Oumuamua was only 100s m in diameter , long period comets are 5-50 km in diameter so the H2 evaporation does not have a strong effect.
If we in for example 100-200 years have invented and perfected some new advanced propulsion system, do we know the orbit of Oumuamua exiting the solar system well enough to catch up to it and find it again?
Yes if we can do it the next decade or so
@@lib8884 Breakthrough Starshot seems to be working on it. I sure hope so. I'd love for scientists to get up-close Mua data in my lifetime.
Did your observations match your ideas? Are you using science?
"it could be a comet after all"; blithering nonsense! No matter how you look at it, it does not meet any of the accepted criteria for being called a "comet". Can nobody accept that we simply don't know? Is saying we don't know what it is that terrifying?
It could be an extremely unlikely comet. Yes it's far more lightly to be a thin sheet of material formed by unknown processes. But I agree this theory about a significant % of the mass of this object being hydrogen gas that has magically been trapped by water ice that also magically didn't also didn't include this water in the outgassing and also magically didn't adjust the spin while outgassing is extremely unlikely. We will know more when lots of interstellar objects are discovered.
It seems to me that we have no problem in saying "we don't know" in most cases. However, when it comes to possibility of artifacts of an extraterrestrial technological civilization (ETC), then we always know for sure:
We know that ETC does not exists, and if they do, they're definitely not close by, or if they are close by, they wouldn't send probes here because we're uninteresting, and even if they would, god forbid, consider us mildly interesting, they couldn't possibly send interstellar probes because of the speed limit. And on and on and on and on ad nauseam.
The bottom line is, that we ALWAYS KNOW FOR SURE it's not ETC. And how do we know this? It's simple. It's not ETC because it cannot be ETC. And because of that, we do not need... No, we must crush, ridicule and ostracize everybody who dares to even consider such a possibility.
More seriously speaking, the same arrogant "we know it all" attitude is quite common in many fields of science. I think science in general is quite well protected against bogus claims, but not so well protected against various sociological phenomena producing bad incentives and amplifying cognitive biases (group-think and taboo subjects are two examples of this).
Besides that, scientist are human after all. There are always jerks who think it's perfectly fine to ridicule everyone who happens to disagree with them. Especially if someone suggests anything outside of the main-stream "party line".
@@esakoivuniemi 👍👍👍
@@Tanks-In-Space 🤡🤡 🤡🤡
What is happening with oxygen during long period changes resulting in and from multi-form change of water ice with liberation/sublimation/squeezing out of hydrogen?
I have heard that for this theory to work the Oxygen has to magically escape
Starts 03:55 good info, thanks for streaming.
Without contradictory? This is how science dies. Condolences!
science is when aliens
Well, look at the authors. What do you expect from outreach/extension classes?
That guy Seti, Sthi, _- he's not a disappointment - not really.. but then, what will we know is when we see one?
& coincidences
Castro's Cigar
The sonofa______ was just another f________ piece of interstellar debris..
ßurely, his was a fragment, from a catastrophic event.
Oumuamua was a craft being pulled by solar sail. That's the simplest explanation.
Excellent. Thank you!
Glad you enjoyed it!
@@SETIInstituteI love how convinced you all are that there is nothing left to know concerning this object. The schadenfreude will be that much sweeter when you are proved wrong.
💫🙏🍻
It is one thing to be biased toward finding no intelligent life in the universe and sad to know you won't.
All 4 wear glasses
An amazing talk, and you take this away from it.
All of these geeks wear glasses!
16 eyes 👀 🤓