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Could Solar Radiation Pressure Explain Oumuamua’s Peculiar Acceleration?

selimthegrim 8y ago
David Brin is sticking to the solar radiation causing outgassing after a delay hypothesis. Go figure - it was his thesis
- ridgeguy 8y ago
  Seems at least plausible. Comet Rosetta's perihelion was August 13, 2015 [1] and there was a big outgassing event February 2016 [2]. Takes time for heat to propagate through stuff. But yeah, I'd rather it was due to radiation pressure on an alien solar sail. [1] https://www.space.com/30237-rosetta-spacecraft-comet-closest-to-sun.html https://www.space.com/30237-rosetta-spacecraft-comet-closest... [2] http://blogs.esa.int/rosetta/2016/08/25/rosetta-captures-comet-outburst/ http://blogs.esa.int/rosetta/2016/08/25/rosetta-captures-com...
vijaybritto 8y ago
I hope it's an alien probe sent by a mother ship. They should come and just destroy us before we slowly destroy ourselves!
- dgzl 8y ago
  Speak for yourself, there's still plenty of things I want to do on this planet.
  - point78 8y ago
    Damn right!
  - radisb 8y ago
    To be fair, he is speaking for himself.
  - vijaybritto 8y ago
    That was a joke
- toasterlovin 8y ago
  > They should come and just destroy us before we slowly destroy ourselves! Your misanthropy doesn’t even make sense. We should be destroyed because we are going to destroy ourselves? As in, we’re going to fall off a cliff, so why not just push us off pre-emptively?
samspenc 8y ago
> We discuss the possible origins of such an object including the possibility that it might be a lightsail of artificial origin. Our general results apply to any light probes designed for interstellar travel. Could someone clarify whether it means what I think it is saying - that an Arxiv paper is trying to prove that this is an object sent by an alien civilization to peek at our solar system?
- grondilu 8y ago
  Yes, it means what you think it means, though "discussing the possibility" does not mean "trying to prove". Weirder Arxiv papers exist, it's not that odd.
- naikrovek 8y ago
  Anyone can publish to Arxiv; one doesn't need to be credible to publish there. I am not saying these authors are untrustworthy, by the way, or that the object in question is or is not of alien & artificial origin; I am saying that anyone can publish a paper to Arxiv.
  - paulpauper 8y ago
    nope. from personal experience trying, you need two endorsements.
  - empath75 8y ago
    They are attached to an institution however.
- tree_of_item 8y ago
  No, you read it wrong. They are not trying to prove anything, they are discussing the possible origins of the object.
mindfulplay 8y ago
Before we jump to artificial/alien origins, let's at least consider the basic science before jumping to fantastical conclusions....
- yantrams 8y ago
  I always found it quite interesting to see the parallels between arguments for God and aliens -- X can't be explained by science so I'm going to jump to the conclusion I want to believe. I thought I was immune to this kind of reasoning but even I fell for it with Oumuamua. The initial paper and comments by some experts convinced me that there is a strong chance that this is a probe. It seemed plausible based on my limited understanding of Physics. (Moment of Inertia, Stresses etc.) But then a paper[1] was released claiming this to be a comet. I so wanted my original belief to be true(because it was more exciting!) I considered the possibility that their [2]model wasn't accurate. I was even willing to entertain the idea of cover-up just because it didn't align with what I wanted to be true! [1] https://www.space.com/41015-interstellar-visitor-oumuamua-comet-after-all.html https://www.space.com/41015-interstellar-visitor-oumuamua-co... [2]A recent study claims that it was indeed the case and the probe is more likely to not be a comet. https://www.quantamagazine.org/interstellar-comet-oumuamua-might-not-actually-be-a-comet-20181010/ https://www.quantamagazine.org/interstellar-comet-oumuamua-m... Edit: Formatting
  - rdtsc 8y ago
    > I always found it quite interesting to see the parallels between arguments for God and aliens -- X can't be explained by science so I'm going to jump to the conclusion I want to believe. In general I think it is because of baggage associated with "God". Which God(s)? Was/is there persecution, torture, killing, suppression of human rights happening or happened using the belief or lack of believe in said God(s) as a pretext. Aliens are a cute curiosity. That is, it is pretty safe to say we believe in them or hope that they visited us without getting too many people upset. Which is kind of what they did here. "Assuming this body can't outgas, and that the acceleration came from the solar wind, then it might have these other properties, including being an alien solar sail"
sunstone 8y ago
When you look at the trajectory that this object took through the solar system, coming within .14 AU of earth, you really have to wonder; what are the chances that it was a random flyby?
- deleted 8y ago
  [deleted]
- vertline3 8y ago
  Well, I think there could be lots of rocks but they are hard to see.
- InclinedPlane 8y ago
  You have to consider instead the probability of detecting such objects that don't come very close to Earth. And that probability is actually pretty low (currently), so the proximity tells us very little beyond some general estimate of how common such objects are.
  - jnicholasp 8y ago
    And in a similar vein, we have only very recently become able to detect (some) objects such as this one, and shortly after we gained the ability to spot things like this, we spotted this one. It at least allows the possibility that events like this are not incredibly rare, and we just haven't been able to perceive them until now.
    - simonh 8y ago
      Plus, it's not as if 0.14 AU (it was actually further than that according to Wikipedia)) is all that close, it was still well over 20 million km away or over 50 lunar orbital radii. It just sounds small when you write it as 0.14 because it's a small fraction of an AU, but an AU is freaking huge. If we sent a probe to Jupiter and it only got within 0.14 AU I can't see that being considered much of a success.
- Afforess 8y ago
deleted 8y ago
[deleted]
jwfxpr 8y ago
The HN title needs to be corrected. The correct name is ʻOumuamua, including the first punctuation character (an ʻokina, representing a glottal stop).
okket 8y ago
Previous discussion from 4 days ago: https://news.ycombinator.com/item?id=18338927 https://news.ycombinator.com/item?id=18338927 (100 comments)

David Brin is sticking to the solar radiation causing outgassing after a delay hypothesis. Go figure - it was his thesis

ridgeguy 8y ago
Seems at least plausible. Comet Rosetta's perihelion was August 13, 2015 [1] and there was a big outgassing event February 2016 [2]. Takes time for heat to propagate through stuff. But yeah, I'd rather it was due to radiation pressure on an alien solar sail. [1] https://www.space.com/30237-rosetta-spacecraft-comet-closest-to-sun.html https://www.space.com/30237-rosetta-spacecraft-comet-closest... [2] http://blogs.esa.int/rosetta/2016/08/25/rosetta-captures-comet-outburst/ http://blogs.esa.int/rosetta/2016/08/25/rosetta-captures-com...

vijaybritto 8y ago

I hope it's an alien probe sent by a mother ship. They should come and just destroy us before we slowly destroy ourselves!

dgzl 8y ago
Speak for yourself, there's still plenty of things I want to do on this planet.
- point78 8y ago
  Damn right!
- radisb 8y ago
  To be fair, he is speaking for himself.
- vijaybritto 8y ago
  That was a joke
toasterlovin 8y ago
> They should come and just destroy us before we slowly destroy ourselves! Your misanthropy doesn’t even make sense. We should be destroyed because we are going to destroy ourselves? As in, we’re going to fall off a cliff, so why not just push us off pre-emptively?

samspenc 8y ago

> We discuss the possible origins of such an object including the possibility that it might be a lightsail of artificial origin. Our general results apply to any light probes designed for interstellar travel. Could someone clarify whether it means what I think it is saying - that an Arxiv paper is trying to prove that this is an object sent by an alien civilization to peek at our solar system?

grondilu 8y ago
Yes, it means what you think it means, though "discussing the possibility" does not mean "trying to prove". Weirder Arxiv papers exist, it's not that odd.
naikrovek 8y ago
Anyone can publish to Arxiv; one doesn't need to be credible to publish there. I am not saying these authors are untrustworthy, by the way, or that the object in question is or is not of alien & artificial origin; I am saying that anyone can publish a paper to Arxiv.
- paulpauper 8y ago
  nope. from personal experience trying, you need two endorsements.
- empath75 8y ago
  They are attached to an institution however.
tree_of_item 8y ago
No, you read it wrong. They are not trying to prove anything, they are discussing the possible origins of the object.

mindfulplay 8y ago

Before we jump to artificial/alien origins, let's at least consider the basic science before jumping to fantastical conclusions....

yantrams 8y ago
I always found it quite interesting to see the parallels between arguments for God and aliens -- X can't be explained by science so I'm going to jump to the conclusion I want to believe. I thought I was immune to this kind of reasoning but even I fell for it with Oumuamua. The initial paper and comments by some experts convinced me that there is a strong chance that this is a probe. It seemed plausible based on my limited understanding of Physics. (Moment of Inertia, Stresses etc.) But then a paper[1] was released claiming this to be a comet. I so wanted my original belief to be true(because it was more exciting!) I considered the possibility that their [2]model wasn't accurate. I was even willing to entertain the idea of cover-up just because it didn't align with what I wanted to be true! [1] https://www.space.com/41015-interstellar-visitor-oumuamua-comet-after-all.html https://www.space.com/41015-interstellar-visitor-oumuamua-co... [2]A recent study claims that it was indeed the case and the probe is more likely to not be a comet. https://www.quantamagazine.org/interstellar-comet-oumuamua-might-not-actually-be-a-comet-20181010/ https://www.quantamagazine.org/interstellar-comet-oumuamua-m... Edit: Formatting
- rdtsc 8y ago
  > I always found it quite interesting to see the parallels between arguments for God and aliens -- X can't be explained by science so I'm going to jump to the conclusion I want to believe. In general I think it is because of baggage associated with "God". Which God(s)? Was/is there persecution, torture, killing, suppression of human rights happening or happened using the belief or lack of believe in said God(s) as a pretext. Aliens are a cute curiosity. That is, it is pretty safe to say we believe in them or hope that they visited us without getting too many people upset. Which is kind of what they did here. "Assuming this body can't outgas, and that the acceleration came from the solar wind, then it might have these other properties, including being an alien solar sail"

sunstone 8y ago

When you look at the trajectory that this object took through the solar system, coming within .14 AU of earth, you really have to wonder; what are the chances that it was a random flyby?

deleted 8y ago
[deleted]
vertline3 8y ago
Well, I think there could be lots of rocks but they are hard to see.
InclinedPlane 8y ago
You have to consider instead the probability of detecting such objects that don't come very close to Earth. And that probability is actually pretty low (currently), so the proximity tells us very little beyond some general estimate of how common such objects are.
- jnicholasp 8y ago
  And in a similar vein, we have only very recently become able to detect (some) objects such as this one, and shortly after we gained the ability to spot things like this, we spotted this one. It at least allows the possibility that events like this are not incredibly rare, and we just haven't been able to perceive them until now.
  - simonh 8y ago
    Plus, it's not as if 0.14 AU (it was actually further than that according to Wikipedia)) is all that close, it was still well over 20 million km away or over 50 lunar orbital radii. It just sounds small when you write it as 0.14 because it's a small fraction of an AU, but an AU is freaking huge. If we sent a probe to Jupiter and it only got within 0.14 AU I can't see that being considered much of a success.
Afforess 8y ago

deleted 8y ago

[deleted]

jwfxpr 8y ago

The HN title needs to be corrected. The correct name is ʻOumuamua, including the first punctuation character (an ʻokina, representing a glottal stop).

okket 8y ago

Previous discussion from 4 days ago: https://news.ycombinator.com/item?id=18338927 https://news.ycombinator.com/item?id=18338927 (100 comments)