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Oumuamua: Alien lightsail probe?

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#26 Gvs

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Posted 10 November 2018 - 09:47 AM

Even though physics is universal. Perception of it, and understanding it are different. In the 1800s physicist consider ether a real thing, today our understanding dark energy or dark matter even m/p theory is limited or wrong at best. As neither can be proven one way or the other.


Our understanding of physics has evolved over time, consequently if aliens exist, the evolution of understanding physics for them will be different then ours, consequently what they leverage as technology will be based on their understanding. So their technology will be different then ours.


For example, if we could show a smartphone shown to Sir Isaac Newton, he would condider it to be magic, as his understanding of physics would not be enough to make sense of it.

Further more, to interpret physics, mathematics is the tool that allows us to model it. Math has evolved over time as well. Today, for most people imaginary numbers, chaos, fractals and lets not get into higher math, these are concepts they barely can grasp.

An average human today would barely be able to leverage the ideal gas law. Askthem to build a reciever from scratch, (I assume most here have done so) they won't be able to do it. And that is simple early 1900s physics. Most will be able to program an arduino to control lights or a stepper motor even create a self walking robot. Because tiday is the technology they understand.

Though if the supply chain for all this tech wasn't there, how many here could create from scratch a simple calculator, a pneumatic controller or a control valve, even a transceiver, better yet an SDF radio! Very few indeed.

My point, any civilization can only leverage what it understands of physics, and the technology derived from it. It can only leverage technology available to all its population in order to speed up development of new technology products and services.

Develoment partners for that technology differ based on the products and services available to them. This is why different countries on Earth have different ways of accessing space, all based on similar technology, though their paths have been different.
  • Astroman007 likes this

#27 Keith Rivich

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Posted 10 November 2018 - 10:29 AM

Maybe it was a turn indicator grin.gif

Couldn’t be. Based on current driving trends no one is using turn signals anymore....including alien Uber drivers. 


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#28 epee

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Posted 10 November 2018 - 11:06 AM

Couldn’t be. Based on current driving trends no one is using turn signals anymore....including alien Uber drivers.

That just proves they are not of this solar system....

Edited by epee, 10 November 2018 - 11:06 AM.


#29 Keith Rivich

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Posted 10 November 2018 - 12:02 PM

Even though physics is universal. Perception of it, and understanding it are different. In the 1800s physicist consider ether a real thing, today our understanding dark energy or dark matter even m/p theory is limited or wrong at best. As neither can be proven one way or the other.


Our understanding of physics has evolved over time, consequently if aliens exist, the evolution of understanding physics for them will be different then ours, consequently what they leverage as technology will be based on their understanding. So their technology will be different then ours.


For example, if we could show a smartphone shown to Sir Isaac Newton, he would condider it to be magic, as his understanding of physics would not be enough to make sense of it.

Further more, to interpret physics, mathematics is the tool that allows us to model it. Math has evolved over time as well. Today, for most people imaginary numbers, chaos, fractals and lets not get into higher math, these are concepts they barely can grasp.

An average human today would barely be able to leverage the ideal gas law. Askthem to build a reciever from scratch, (I assume most here have done so) they won't be able to do it. And that is simple early 1900s physics. Most will be able to program an arduino to control lights or a stepper motor even create a self walking robot. Because tiday is the technology they understand.

Though if the supply chain for all this tech wasn't there, how many here could create from scratch a simple calculator, a pneumatic controller or a control valve, even a transceiver, better yet an SDF radio! Very few indeed.

My point, any civilization can only leverage what it understands of physics, and the technology derived from it. It can only leverage technology available to all its population in order to speed up development of new technology products and services.

Develoment partners for that technology differ based on the products and services available to them. This is why different countries on Earth have different ways of accessing space, all based on similar technology, though their paths have been different.

I think you overestimate the capabilities of what common people of yore achieved. I bet even in the height of the "build your own radio craze" of the early 20th century only a few folks had the know how to do so. In the time of Newton I bet 99.9% of the population couldn't multiply fractions, let alone grasp higher math. 

 

Today most folks are happy with their electronics without a blip of knowledge on how it works. They watch "Ghost Hunters" on their TV's and truly believe ghost exist, an idea which is totally incompatible with the physics that allows them to receive and watch the show!

 

On Oumuamua:

 

This is probably how a first real encounter will look. A fast flyby by a probe using the sun as a slingshot to reach its next target, collecting data along the way. Perhaps even looping around to return samples and data to its senders descendants. 



#30 Jason H.

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Posted 14 November 2018 - 10:46 PM

Regarding “Could Solar Radiation Pressure Explain ‘Oumuamua’s Peculiar Acceleration?”
http://adsabs.harvar...arXiv181011490B

My personal opinion is that it would be very nice if what they were speculating were to turn out to be true, however, the following comes to mind:

 

1. “Based on the survey properties and the single detection, Do et. a (2018) estimated that interstellar density…”

In statistical analysis, we cannot imply a population or derive statistics from a sample of one. This is the same problem as in the SETI.

 

2. “…if outgassing was responsible for acceleration (as originally proposed by Micheli et al. 2018), then the associated outgassing torques would have driven a rapid evolution in “Oumoumua’s spin, incompatible with observations.”

 

Considering the short observation period of this object, combined with the already rapid rotation, odd shape of at least 5:1, and albedo variability indicating a complex aperiodic presentation of specific surface features, I suspect that there’s a good chance that we could not detect changes due to torque imposed vector variation due to it’s chaos-like tumbling presentation in a such a short sample (the animation and light curves of which can be seen at the wikipedia article https://en.wikipedia.../wiki/'Oumuamua .)

 

3. “This work was supported in part by a grant from the Breakthrough Prize Foundation”.

 

This reminds me of clinical drug trials sponsored by pharmaceutical companies, smoking studies by cigarette companies, or environmental studies by petrochemical companies; there’s reason to suspect biased thinking in the paper. Breakthrough Initatives, https://en.wikipedia...ugh_Initiatives is a multi-pronged effort, but what’s interesting here is that this paper brings together two separate areas of their investigation (SETI and Starshot) into one contemplation. Regarding the objectivity of the investigators, one has to ask, do the authors have other works in progress or that they’ve previously written that would cause them to want to validate their prior or current works? The answer IMO is yes (based on their other published works). Not that that’s necessarily a bad thing; people looking at a specific series of questions/problems will often tend to be the first to observe characteristics of objects that fit with patterns they’ve observed previously, but the human tendency to super-impose perspectives based on past experience, or fill in the dots if you will, can be a myopic experiential bias that has no basis in reality (i.e. why focus on light sails?). More specifically, they see things in terms of light sails because that’s what they do every day, not necessarily wrong, but suspect in the least. Why would E.T.’s use a form of propulsion that is consistent with the prior work of the authors? In the least it’s highly coincidental, at worst it seems self-serving IMO.

 

4. “Although ‘Oumamua has a red surface color, similar to organic-rich surfaces of Solar-System comets and D-type asteroids (Meech et al. 2017) this does not contradict the artificial scenario, since irrespective of the object’s composition, as it travels through the ISM its surface will be covered by a layer of interstellar dust, which itself is composed of organic-rich materials (Draine 2003.)”
 

IMO this is highly contradictory! If one follows this reference to the Draine 2003 paper, one sees that there is absolutely no indication of how long it would take for ISM dust deposition to occur in sufficient amounts to alter the presentation of a light sail to appear to be comet/asteroid like. Indeed this seems very contradictory to their argument that this could be a purposefully directed probe, as IMO a directed probe would not seek to be coated in ISM dust to impair the light sail performance (indeed it might actively seek to clean/remove it over time). And if E.T.’s were trying to be a camouflaged probe, I would not think it stealthful to present an asteroid with unnatural/non-keplerian motion while still within easy imaging range.

 

5. If it’s technological detritus, this seems antithetical to its behaviors of being a directed probe (i.e. the close solar passage.) It seems to me that that finding (by others) 

Kinematics of the Interstellar Vagabond 1I/’Oumuamua (A/2017 U1) Eric Mamajek
https://arxiv.org/abs/1710.11364

“…In the Local Standard of Rest frame (circular Galactic motion), ‘Oumuamua is remarkable for showing both negligible radial (U) and vertical (W) motion, while having a slightly sub-Keplerian circular velocity (V; by ~11 km/s). These calculations strengthen the interpretation that A/2017 U1 has a distant extrasolar origin, but not among the very nearest stars. Any formation mechanism for this interstellar asteroid should account for the coincidence of ‘Oumuamua’s velocity being so close to the LSR.”

 

I think this argues against the probe actively accelerating with a purpose, and is more like being drifting galactic sea foam (metaphor) that our Sun has overtaken.

 

6. And last but certainly not least is
“Since it is too late to image ‘Oumuamua with existing telescopes or chase it with chemical rockets (Seligman & Laughlin 2018), its likely origin and mechanical properties could only be deciphered by searching for other objects of its type in the future.”

 

They might as well have said, since our paper is not scientifically provable, we can say whatever we want. Being unable to further test any of their suppositions by further observation of proposed characteristics (jet-caused torque, non-keplerian motion or other inexplicable behaviors) puts their speculation into a highly anti-scientific realm IMO (even SETI seeks repeatability/testability).

 

(but I hope they are right :^)
Jason W. Higley


Edited by Jason H., 14 November 2018 - 10:52 PM.


#31 DaveC2042

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Posted Yesterday, 12:12 AM

Regarding “Could Solar Radiation Pressure Explain ‘Oumuamua’s Peculiar Acceleration?”
http://adsabs.harvar...arXiv181011490B

My personal opinion is that it would be very nice if what they were speculating were to turn out to be true, however, the following comes to mind:

 

1. “Based on the survey properties and the single detection, Do et. a (2018) estimated that interstellar density…”

In statistical analysis, we cannot imply a population or derive statistics from a sample of one. This is the same problem as in the SETI.

 

2. “…if outgassing was responsible for acceleration (as originally proposed by Micheli et al. 2018), then the associated outgassing torques would have driven a rapid evolution in “Oumoumua’s spin, incompatible with observations.”

 

Considering the short observation period of this object, combined with the already rapid rotation, odd shape of at least 5:1, and albedo variability indicating a complex aperiodic presentation of specific surface features, I suspect that there’s a good chance that we could not detect changes due to torque imposed vector variation due to it’s chaos-like tumbling presentation in a such a short sample (the animation and light curves of which can be seen at the wikipedia article https://en.wikipedia.../wiki/'Oumuamua .)

 

3. “This work was supported in part by a grant from the Breakthrough Prize Foundation”.

 

This reminds me of clinical drug trials sponsored by pharmaceutical companies, smoking studies by cigarette companies, or environmental studies by petrochemical companies; there’s reason to suspect biased thinking in the paper. Breakthrough Initatives, https://en.wikipedia...ugh_Initiatives is a multi-pronged effort, but what’s interesting here is that this paper brings together two separate areas of their investigation (SETI and Starshot) into one contemplation. Regarding the objectivity of the investigators, one has to ask, do the authors have other works in progress or that they’ve previously written that would cause them to want to validate their prior or current works? The answer IMO is yes (based on their other published works). Not that that’s necessarily a bad thing; people looking at a specific series of questions/problems will often tend to be the first to observe characteristics of objects that fit with patterns they’ve observed previously, but the human tendency to super-impose perspectives based on past experience, or fill in the dots if you will, can be a myopic experiential bias that has no basis in reality (i.e. why focus on light sails?). More specifically, they see things in terms of light sails because that’s what they do every day, not necessarily wrong, but suspect in the least. Why would E.T.’s use a form of propulsion that is consistent with the prior work of the authors? In the least it’s highly coincidental, at worst it seems self-serving IMO.

 

4. “Although ‘Oumamua has a red surface color, similar to organic-rich surfaces of Solar-System comets and D-type asteroids (Meech et al. 2017) this does not contradict the artificial scenario, since irrespective of the object’s composition, as it travels through the ISM its surface will be covered by a layer of interstellar dust, which itself is composed of organic-rich materials (Draine 2003.)”
 

IMO this is highly contradictory! If one follows this reference to the Draine 2003 paper, one sees that there is absolutely no indication of how long it would take for ISM dust deposition to occur in sufficient amounts to alter the presentation of a light sail to appear to be comet/asteroid like. Indeed this seems very contradictory to their argument that this could be a purposefully directed probe, as IMO a directed probe would not seek to be coated in ISM dust to impair the light sail performance (indeed it might actively seek to clean/remove it over time). And if E.T.’s were trying to be a camouflaged probe, I would not think it stealthful to present an asteroid with unnatural/non-keplerian motion while still within easy imaging range.

 

5. If it’s technological detritus, this seems antithetical to its behaviors of being a directed probe (i.e. the close solar passage.) It seems to me that that finding (by others) 

Kinematics of the Interstellar Vagabond 1I/’Oumuamua (A/2017 U1) Eric Mamajek
https://arxiv.org/abs/1710.11364

“…In the Local Standard of Rest frame (circular Galactic motion), ‘Oumuamua is remarkable for showing both negligible radial (U) and vertical (W) motion, while having a slightly sub-Keplerian circular velocity (V; by ~11 km/s). These calculations strengthen the interpretation that A/2017 U1 has a distant extrasolar origin, but not among the very nearest stars. Any formation mechanism for this interstellar asteroid should account for the coincidence of ‘Oumuamua’s velocity being so close to the LSR.”

 

I think this argues against the probe actively accelerating with a purpose, and is more like being drifting galactic sea foam (metaphor) that our Sun has overtaken.

 

6. And last but certainly not least is
“Since it is too late to image ‘Oumuamua with existing telescopes or chase it with chemical rockets (Seligman & Laughlin 2018), its likely origin and mechanical properties could only be deciphered by searching for other objects of its type in the future.”

 

They might as well have said, since our paper is not scientifically provable, we can say whatever we want. Being unable to further test any of their suppositions by further observation of proposed characteristics (jet-caused torque, non-keplerian motion or other inexplicable behaviors) puts their speculation into a highly anti-scientific realm IMO (even SETI seeks repeatability/testability).

 

(but I hope they are right :^)
Jason W. Higley

The cynic in me wonders about the game theory aspect of this:

  • If you are wrong, who cares, it was just speculation - 99.999...% likelihood with no downside;
  • If you turn out to be right, you get a Nobel Prize - 0.000...1% longshot, but with no real cost attached.


#32 Astroman007

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Posted Yesterday, 01:27 AM

https://www.earthfil...ightsail-power/



#33 Mister T

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Posted Yesterday, 07:36 AM

After reading all this conjecture about an object that just "fell past our window"..

Leads me to conclude that Oumuamua is composed chiefly of bovine excrement

 

smirk.gif 

 



#34 llanitedave

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Posted Yesterday, 07:47 PM


My personal opinion is that it would be very nice if what they were speculating were to turn out to be true, however, the following comes to mind:

 

1. “Based on the survey properties and the single detection, Do et. a (2018) estimated that interstellar density…”

In statistical analysis, we cannot imply a population or derive statistics from a sample of one. This is the same problem as in the SETI.

 

 

If we ever detect incoming interstellar visitors with a sample size greater than 1, I'm heading for the hills!




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