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Consider the statistics of it being an alien probe. Now consider the statistics of it being a rock. It's a rock.

by 1970-01-01 4y ago

daveslash 4y ago
Stand back, this guy/gal's using Occam's Razor! They'll cut you!
david927 4y ago
What is that called? Occam's Blindfold? We don't know it's a rock. We don't really know what it is, other than it's the first thing we've picked up from an interstellar trajectory, is bizarrely shaped, didn't reflect the pull from the sun, swung by the Earth and then accelerated away.
- monkeydreams 4y ago
  It's Occam's Razor. In order for it to be an interstellar rock, you require no other assumption because there is little evidence to suggest it isn't. If you believe it is a probe you must assume an alien civilisation. Occam's Razor suggests fewest assumptions win.
  - twawaaay 4y ago
    Except the whole discussion is still here exactly because there is evidence to suggest it isn't a rock. Supposedly it accelerated a bit, inconsistent with what we know about how rocks move through space.
  - david927 4y ago
    I made a “play on words” to convey the notion of discarding data in the insistence on coming to a conclusion rather than simply holding ambiguity. No decision needs to be made. We don’t know if it’s a rock or anything else and that’s ok.
  - DennisP 4y ago
    You don't have to believe it's an alien probe to accept the substantial evidence that it's not a simple rock.
    - vecter 4y ago
      There is no such "substantial" evidence. If there really was scientifically agreed upon "substantial" evidence, then it would be world-shattering news.
      - DennisP 4y ago
        Why? It's some weird object that's not a simple rock. Most people don't see that as earth-shattering, just weird. The basic weirdness is this: it didn't move like a rock, and anything normal that outgassed from it would have been visible, but it wasn't. There have been a couple hypotheses for weird things it could have been made of, but those ideas look unlikely for their own reasons. One for example was that it was frozen hydrogen, but that would have evaporated in interstellar space. The earth has not shattered because most people assume there's a reasonable explanation that nobody's figured out yet.
- threatofrain 4y ago
  A better reframing of the same concept is scientific parsimony, which suggests a heuristic for economical empiricism. Occam’s Razor suggests to people that probability is somehow being calculated.
- lamontcg 4y ago
  The delta-V from non gravitational forces was only 17 m/s or 38 mph. By comparison it has a hyperbolic excess velocity of 26.33 km/s and its maximum speed was 87.71 km/s. Its "maneuvering acceleration" amounted to 0.02% of its maximum velocity. That is all consistent with some combination of radiation pressure, solar wind and offgassing. Its closest approach to Earth was 0.1618 AU which is not terribly remarkable, it isn't like it did a close flyby in between the Earth and Moon or something. We also now know that planetary systems are incredibly common, it is almost certain that Oort clouds are incredibly common. And while stars rarely collide, they do commonly come close enough to gravitationally interaction, and it is likely that material would be flung into interstellar space by that. Our imagination of interstellar space being just gas and dust and otherwise empty is likely very incorrect.
  - david927 4y ago
    Thank you. I stand corrected. And yet... you have to admit it’s intriguing...
    - lamontcg 4y ago
      It is intriguing because it may have been ejected after a star went red giant and stripped most of its volatiles from it, a billion years ago and wandered across the galaxy very slowly until it first encountered our solar system. It would have been incredible to be able to put together a lander mission, but the direct delta-V to rendezvous would be ludicrous.
      - actionfromafar 4y ago
        A fast fly-by would not have been though, if it had launched as soon as we saw it.
        haimez 4y ago
        A “direct intercept” like you’re suggesting gives you very little time to take any measurements even if we had a vehicle standing by. For now it’s not the kind of mission NASA has chosen to fund just in case they got the opportunity to scramble a one time fly-by mission to collect a few seconds of data on an object that happened to streak past us this millennia.
flaque 4y ago
This argument doesn't work, because you don't know the statistics of it being an alien probe.
- not2b 4y ago
  That's not how it works: you start with the null hypothesis and you try to see if you can reject that with some confidence interval. In this case, the null hypothesis is that it's some kind of ordinary object, and its path is determined by gravity, radiation pressure, and outgassing. Only if you can demonstrate why this is highly improbable can you start talking about alien probes. As others have argued in this thread, once you do this kind of analysis there's nothing left that is odd and needs explaining.
LargoLasskhyfv 4y ago
Wasn't the whole thing about that it didn't move like a rock?
twawaaay 4y ago
So... any statistics on rocks that can accelerate on their own?
postalrat 4y ago
What are the statistics of rocks that behave like rocks?
throwawaylinux 4y ago
What are "the statistics of it being a rock"? Of all the interstellar objects like this one we have observed, how many were rocks?
edgyquant 4y ago
How can we consider those statistics if we don’t know how common alien civilizations, or their sending of rocks, is?
aceazzameen 4y ago
I'm not sure what it is, but I'm in the camp that it's most likely a rock. But a very interesting rock! Especially considering it changed its trajectory but not its spin. It's extremely unlikely to be a probe because it's heading in a different direction from where it came from. And if it's an interstellar traveler, it's probably going too slow, or at least hasn't bothered to pick up speed as it exits. I don't think we'll ever truly know enough about it. Even as just a rock, there's a ton to learn there! And sadly we'll only ever have a small slice of data about it.
- JackFr 4y ago
  Obviously it was ejected mass used to reduce the velocity of the invasion vessel due in about 75 years.
xwdv 4y ago
This is disingenuous, an example of twisting statistics for your own karmic gain. The fact is, if you consider the statistics of it being a rock that also behaves in the peculiar flight pattern that this thing took, it could very well be a probe.
deleted 4y ago
[deleted]

Consider the statistics of it being an alien probe. Now consider the statistics of it being a rock. It's a rock.

Stand back, this guy/gal's using Occam's Razor! They'll cut you!

What is that called? Occam's Blindfold? We don't know it's a rock. We don't really know what it is, other than it's the first thing we've picked up from an interstellar trajectory, is bizarrely shaped, didn't reflect the pull from the sun, swung by the Earth and then accelerated away.

monkeydreams 4y ago
It's Occam's Razor. In order for it to be an interstellar rock, you require no other assumption because there is little evidence to suggest it isn't. If you believe it is a probe you must assume an alien civilisation. Occam's Razor suggests fewest assumptions win.
- twawaaay 4y ago
  Except the whole discussion is still here exactly because there is evidence to suggest it isn't a rock. Supposedly it accelerated a bit, inconsistent with what we know about how rocks move through space.
- david927 4y ago
  I made a “play on words” to convey the notion of discarding data in the insistence on coming to a conclusion rather than simply holding ambiguity. No decision needs to be made. We don’t know if it’s a rock or anything else and that’s ok.
- DennisP 4y ago
  You don't have to believe it's an alien probe to accept the substantial evidence that it's not a simple rock.
  - vecter 4y ago
    There is no such "substantial" evidence. If there really was scientifically agreed upon "substantial" evidence, then it would be world-shattering news.
    - DennisP 4y ago
      Why? It's some weird object that's not a simple rock. Most people don't see that as earth-shattering, just weird. The basic weirdness is this: it didn't move like a rock, and anything normal that outgassed from it would have been visible, but it wasn't. There have been a couple hypotheses for weird things it could have been made of, but those ideas look unlikely for their own reasons. One for example was that it was frozen hydrogen, but that would have evaporated in interstellar space. The earth has not shattered because most people assume there's a reasonable explanation that nobody's figured out yet.
threatofrain 4y ago
A better reframing of the same concept is scientific parsimony, which suggests a heuristic for economical empiricism. Occam’s Razor suggests to people that probability is somehow being calculated.
lamontcg 4y ago
The delta-V from non gravitational forces was only 17 m/s or 38 mph. By comparison it has a hyperbolic excess velocity of 26.33 km/s and its maximum speed was 87.71 km/s. Its "maneuvering acceleration" amounted to 0.02% of its maximum velocity. That is all consistent with some combination of radiation pressure, solar wind and offgassing. Its closest approach to Earth was 0.1618 AU which is not terribly remarkable, it isn't like it did a close flyby in between the Earth and Moon or something. We also now know that planetary systems are incredibly common, it is almost certain that Oort clouds are incredibly common. And while stars rarely collide, they do commonly come close enough to gravitationally interaction, and it is likely that material would be flung into interstellar space by that. Our imagination of interstellar space being just gas and dust and otherwise empty is likely very incorrect.
- david927 4y ago
  Thank you. I stand corrected. And yet... you have to admit it’s intriguing...
  - lamontcg 4y ago
    It is intriguing because it may have been ejected after a star went red giant and stripped most of its volatiles from it, a billion years ago and wandered across the galaxy very slowly until it first encountered our solar system. It would have been incredible to be able to put together a lander mission, but the direct delta-V to rendezvous would be ludicrous.
    - actionfromafar 4y ago
      A fast fly-by would not have been though, if it had launched as soon as we saw it.
      - haimez 4y ago
        A “direct intercept” like you’re suggesting gives you very little time to take any measurements even if we had a vehicle standing by. For now it’s not the kind of mission NASA has chosen to fund just in case they got the opportunity to scramble a one time fly-by mission to collect a few seconds of data on an object that happened to streak past us this millennia.

flaque 4y ago

This argument doesn't work, because you don't know the statistics of it being an alien probe.

not2b 4y ago
That's not how it works: you start with the null hypothesis and you try to see if you can reject that with some confidence interval. In this case, the null hypothesis is that it's some kind of ordinary object, and its path is determined by gravity, radiation pressure, and outgassing. Only if you can demonstrate why this is highly improbable can you start talking about alien probes. As others have argued in this thread, once you do this kind of analysis there's nothing left that is odd and needs explaining.

LargoLasskhyfv 4y ago

Wasn't the whole thing about that it didn't move like a rock?

twawaaay 4y ago

So... any statistics on rocks that can accelerate on their own?

postalrat 4y ago

What are the statistics of rocks that behave like rocks?

throwawaylinux 4y ago

What are "the statistics of it being a rock"? Of all the interstellar objects like this one we have observed, how many were rocks?

edgyquant 4y ago

How can we consider those statistics if we don’t know how common alien civilizations, or their sending of rocks, is?

aceazzameen 4y ago

I'm not sure what it is, but I'm in the camp that it's most likely a rock. But a very interesting rock! Especially considering it changed its trajectory but not its spin. It's extremely unlikely to be a probe because it's heading in a different direction from where it came from. And if it's an interstellar traveler, it's probably going too slow, or at least hasn't bothered to pick up speed as it exits. I don't think we'll ever truly know enough about it. Even as just a rock, there's a ton to learn there! And sadly we'll only ever have a small slice of data about it.

JackFr 4y ago
Obviously it was ejected mass used to reduce the velocity of the invasion vessel due in about 75 years.

xwdv 4y ago

This is disingenuous, an example of twisting statistics for your own karmic gain. The fact is, if you consider the statistics of it being a rock that also behaves in the peculiar flight pattern that this thing took, it could very well be a probe.

deleted 4y ago

[deleted]