6 ms·

On a similar vein there's Project Lyra which is a theoretical fly-by mission of ʻOumuamua or 2I/Borisov. The proposed trajectories to catch up are pretty crazy

by rtkwe 1y ago

On a similar vein there's Project Lyra which is a theoretical fly-by mission of ʻOumuamua or 2I/Borisov. The proposed trajectories to catch up are pretty crazy with my favorite being the 2030 launch for a 2052 fly-by that uses Jupiter and a close Sol 10 solar radii!) gravity assist to rocket out of the solar system [0]. It will be interesting to see if we've just been missing these extra solar objects. I have doubts we'll actually do a project Lyra style fly-by though. Funding is going the opposite direction and all. [0] http://orbitsimulator.com/BA/lyra.gif http://orbitsimulator.com/BA/lyra.gif and https://i4is.org/project-lyra-a-solar-oberth-at-10-solar-radii/#gsc.tab=0 https://i4is.org/project-lyra-a-solar-oberth-at-10-solar-rad...

jerf 1y ago
I'd expect this is just the lamppost effect and we'll start seeing lots of these. It means there's no great need to chase any particular one of them, we can almost certainly wait until we're ready, then pick one that is convenient at the time. It also means that "Oumuamua is an alien craft!" will almost certainly join in the ignoble legacy of "thinking the first instance of a new thing must be ALIENS" once we've detected hundreds of these (or more, depending on how sensitive we can get). You'd really think we'd be over this by now, but apparently not.
- __MatrixMan__ 1y ago
  If we ever stop being excited about the possibility that poorly understood phenomena are evidence of undiscovered intelligent life the we'll have lost a part of our humanity.
  - pfdietz 1y ago
    That's just bullshit. The idea that undiscovered intelligent life is a plausible explanation for such things is just the triumph of numerically illiterate wishful thinking over rational thought.
    - foxglacier 1y ago
      It's a triumph of humanity over rational thought. Imagining intelligent beings is a core part of being human. We do it with gods, ghosts, monsters, etc. It's exciting and it's kind of a major reason we're exploring space to begin with. If you want pure rationality, might as well kill all astronomy research because what's the point? We do it because it's exciting to discover things, not for any practical purpose.
    - __MatrixMan__ 1y ago
      I'm not saying that it's a conclusion that we should jump to. Just that it's silly to expect people not to consider it first. It's more related to why we're looking up in the first place than any of its alternatives.
      - pfdietz 1y ago
        It's so ridiculous that the only reason to expend a single keystroke on it is to demolish it. Consider what the implication would be if these are ET spacecraft. The galaxy would be absolute soaked in ETI. The Fermi argument would then bite maximally: why did we even evolve, if the galaxy has been so saturated? Why wasn't every single planet and asteroid used for colonies and resources ages ago? It's important to realize that science fictional tropes of galaxies with everyone zooming around in spaceships having adventures are not consistent with what we observe.
        __MatrixMan__ 1y ago
        What does the low probability have to do with it? If you had asked Galileo's contemporaries about the probability that he'd find moons orbiting Jupiter, they'd have put it at zero, and they turned out to be wrong. Einstein's work was also in flagrant disregard of the established scientific sensibilities of the time. I can't speak for everybody, but the excitement that I get when I look through a telescope, or a microscope, or commune with any machine that can see something that I can't... it comes from the possibility that I'll see something impossible, something that invalidates the theories which previously governed what I'm likely to see. It's why we keep building better telescopes and bigger particle colliders--because we want to prove ourselves wrong. It's fine to be a rationalist with an appreciation for existing theory, but it's not irrationality when others attempt to invalidate what you're protecting--thats where progress comes from. We wouldn't know as much as we do without the people who look for things that shouldn't be there on the basis of viewpoints outside of accepted theory.
- MarkusQ 1y ago
  I remember the first time I heard of that pattern of thinking. My initial reaction was "OMG, it must be aliens!" Then I thought "now wait a minute...hold on..."
- rtkwe 1y ago
  It's not so much a matter of being ready, it's a matter of what planets are where that we can get a boost out of to get those speeds. Even with a fleet of working starships and assembling something in orbit getting up the to speed of these extra solar objects practically requires some intense maneuvers near conveniently positioned and timed planets.
- dbingham 1y ago
  Please correct me if I'm wrong, but my understand of the alien craft theory specifically for Oumuamua wasn't just because the object itself was new, but that it changed acceleration [1] without apparent off gassing in a way that isn't explained by our current understanding of orbital physics for a natural object. It's not just "New object, must be aliens!" It's "This thing doesn't fit our understanding of orbital motion for natural objects, aliens is actually a rational, if still unlikely, possible explanation." [1] https://en.wikipedia.org/wiki/1I/%CA%BBOumuamua#Non-gravitational_acceleration https://en.wikipedia.org/wiki/1I/%CA%BBOumuamua#Non-gravitat...
  - ryanblakeley 1y ago
    There were a number of anomalous characteristics including its shape, acceleration, rotation, origin, and reflectivity.
    - ceejayoz 1y ago
      How do we know they're anomalous characteristics if it's literally the first one we've ever spotted? What is the normal shape of an interstellar comet core?
      - cubefox 1y ago
        For example, being flat like a pancake is obviously highly unusual and very different from anything we have seen from stellar comets.
        ceejayoz 1y ago
        Stellar comets haven't been ejected from another solar system. We have vanishingly few examples of those, and we've not directly observed any up close. "Flat as a pancake" is one of several theoretical possibilities from its light curve, not a known fact about the object. "Highly unusual" in space tends to mean "there are a bunch, but we haven't seen them until now". In 1992, exoplanets were "highly unusual". Now they're everywhere.
- deleted 1y ago
  [deleted]
- cubefox 1y ago
  > It also means that No, it doesn't mean that. What makes 'Oumuamua special is not the fact that we didn't see interstellar objects before. It's rather the fact that 'Oumuamua has highly unusual and hard to explain properties. Avi Loeb: > ‘Oumuamua exhibited a non-gravitational acceleration of 4.92 ± 0.16 × 10^⁻6 m/s² that decreased proportionally to 1/r², where r represents the heliocentric distance, corresponding to a formal ~30 σ detection of non-gravitational acceleration (Micheli et al., 2018). The inverse-square relationship typically indicates radiation pressure or outgassing forces. However, despite extensive observations by the Spitzer Space Telescope, no carbon-based molecules, dust, or thermal emission indicative of cometary outgassing were detected (Trilling et al., 2018). Such a paradox — acceleration without observable mass loss — violates fundamental assumptions about how small bodies behave in the solar system. > The object’s extreme geometry presented another unprecedented observation. ‘Oumuamua’s brightness varied by a factor of 10 during its 8-hour rotation period, indicating an extreme geometry with an aspect ratio exceeding 10:1 (Drahus et al., 2018; Meech et al., 2017). Such extreme elongation is unprecedented among known Solar System objects, leading to competing interpretations of either a cigar-shaped or pancake-like geometry (Belton et al., 2018; Luu et al., 2020; Mashchenko, 2019; Moro-Martín, 2019a,b; Zhang & Lin, 2020). > More significantly, ‘Oumuamua entered the Solar System with a velocity remarkably close to the Local Standard of Rest (LSR). The object’s velocity before encountering the Solar System was within approximately 6 km/s of the local median stellar velocity and just 11 km/s from the LSR, with negligible radial and vertical Galactic motion (Mamajek, 2017). Fewer than 1 in 500 stars share such kinematics, making ‘Oumuamua’s near-stationary approach highly improbable for a naturally ejected object from a nearby star system (Loeb, 2022). Natural ejection mechanisms from planetary systems typically impart the host star’s peculiar velocity to expelled bodies, yet ‘Oumuamua appeared to originate from the most kinematically common frame of reference in our Galactic neighborhood (Loeb, 2022; Mamajek, 2017). > The object’s rotational dynamics added another layer of complexity. ‘Oumuamua displayed non-principal axis rotation, exhibiting a tumbling motion rather than spinning around a single axis. Such a rotational state is unusual for an object that has been traveling through interstellar space for potentially billions of years, as collisions and internal friction should have damped its motion to simple rotation (Belton et al., 2018; Fraser et al., 2018). > Finally, the object’s slightly red color differed from both typical comets and asteroids. Its spectral properties showed no absorption features that would indicate specific mineral compositions, making it difficult to determine its definite surface composition (Jewitt et al., 2017; Ye et al., 2017). This spectral ambiguity prevented researchers from determining surface composition through standard techniques, leaving the object’s fundamental nature — rocky, icy, or something else entirely — unresolved. https://avi-loeb.medium.com/scientific-paradigm-resistance-evidence-from-the-oumuamua-debate-and-cross-disciplinary-cases-c5a4c341a355 https://avi-loeb.medium.com/scientific-paradigm-resistance-e...
api 1y ago
Rendezvous with one of these would be a good use for a NERVA-type nuclear engine (upper stage, not used in the atmosphere). Also seems like the thing to do, given that we are finding more than one of these now, is to build such a thing and have it on standby and look for one that's inbound so we can launch at the best window to reach it.
- rtkwe 1y ago
  Even with a NERVA engine it's a LOT of work to get to the 26 kmps of an object like ʻOumuamua so you're still at the mercy of planets being in roughly the right locations to provide some gravity assists. I think it would widen the workable solutions but something like the 10 SR assist could work with things we've actually built already.
- dylan604 1y ago
  to build a thing would be astonishingly lucky for it be parked in the right place to catch the next one, so where would you park it? seems like it would be better to build a lot of them, and park them through out in various orbits so maybe one of them has a chance to rendezvous
  - api 1y ago
    I was thinking park it on Earth. Have something ready to launch that consists of a very spicy nuclear upper stage to yeet a small probe at very high speed. The whole upper stages assembly and probe could be sitting there ready to be sent up on a Falcon Heavy or Starship class booster. Might even use an expendable launch to send the upper stage into the highest energy trajectory possible. I wonder how small you could make the probe vs how big the booster and upper stages assembly could be and how fast such a thing could be yeet. I’m thinking even a glorified cubesat size thing paired with a whole lot of rocket. It wouldn’t slow down. It would be a flyby. But it would get us high resolution images and scans and spectroscopic readings, and if one of these visitors was artificial that would become quite obvious with a good picture.
m4rtink 1y ago
Solar Oberth manuever FTW! :D The High Frontier board game from Phil Eklund even has it as a valid option on its orbital map of the Solar system. :)
- rtkwe 1y ago
  A ten solar radii oberth maneuver too! Which is only slightly farther than the Parker Solar probe got (3.8 million miles vs ~4.3 million for that Lyra proposal)

by rtkwe 1y ago

jerf 1y ago

I'd expect this is just the lamppost effect and we'll start seeing lots of these. It means there's no great need to chase any particular one of them, we can almost certainly wait until we're ready, then pick one that is convenient at the time. It also means that "Oumuamua is an alien craft!" will almost certainly join in the ignoble legacy of "thinking the first instance of a new thing must be ALIENS" once we've detected hundreds of these (or more, depending on how sensitive we can get). You'd really think we'd be over this by now, but apparently not.

__MatrixMan__ 1y ago
If we ever stop being excited about the possibility that poorly understood phenomena are evidence of undiscovered intelligent life the we'll have lost a part of our humanity.
- pfdietz 1y ago
  That's just bullshit. The idea that undiscovered intelligent life is a plausible explanation for such things is just the triumph of numerically illiterate wishful thinking over rational thought.
  - foxglacier 1y ago
    It's a triumph of humanity over rational thought. Imagining intelligent beings is a core part of being human. We do it with gods, ghosts, monsters, etc. It's exciting and it's kind of a major reason we're exploring space to begin with. If you want pure rationality, might as well kill all astronomy research because what's the point? We do it because it's exciting to discover things, not for any practical purpose.
  - __MatrixMan__ 1y ago
    I'm not saying that it's a conclusion that we should jump to. Just that it's silly to expect people not to consider it first. It's more related to why we're looking up in the first place than any of its alternatives.
    - pfdietz 1y ago
      It's so ridiculous that the only reason to expend a single keystroke on it is to demolish it. Consider what the implication would be if these are ET spacecraft. The galaxy would be absolute soaked in ETI. The Fermi argument would then bite maximally: why did we even evolve, if the galaxy has been so saturated? Why wasn't every single planet and asteroid used for colonies and resources ages ago? It's important to realize that science fictional tropes of galaxies with everyone zooming around in spaceships having adventures are not consistent with what we observe.
      - __MatrixMan__ 1y ago
        What does the low probability have to do with it? If you had asked Galileo's contemporaries about the probability that he'd find moons orbiting Jupiter, they'd have put it at zero, and they turned out to be wrong. Einstein's work was also in flagrant disregard of the established scientific sensibilities of the time. I can't speak for everybody, but the excitement that I get when I look through a telescope, or a microscope, or commune with any machine that can see something that I can't... it comes from the possibility that I'll see something impossible, something that invalidates the theories which previously governed what I'm likely to see. It's why we keep building better telescopes and bigger particle colliders--because we want to prove ourselves wrong. It's fine to be a rationalist with an appreciation for existing theory, but it's not irrationality when others attempt to invalidate what you're protecting--thats where progress comes from. We wouldn't know as much as we do without the people who look for things that shouldn't be there on the basis of viewpoints outside of accepted theory.
MarkusQ 1y ago
I remember the first time I heard of that pattern of thinking. My initial reaction was "OMG, it must be aliens!" Then I thought "now wait a minute...hold on..."
rtkwe 1y ago
It's not so much a matter of being ready, it's a matter of what planets are where that we can get a boost out of to get those speeds. Even with a fleet of working starships and assembling something in orbit getting up the to speed of these extra solar objects practically requires some intense maneuvers near conveniently positioned and timed planets.
dbingham 1y ago
Please correct me if I'm wrong, but my understand of the alien craft theory specifically for Oumuamua wasn't just because the object itself was new, but that it changed acceleration [1] without apparent off gassing in a way that isn't explained by our current understanding of orbital physics for a natural object. It's not just "New object, must be aliens!" It's "This thing doesn't fit our understanding of orbital motion for natural objects, aliens is actually a rational, if still unlikely, possible explanation." [1] https://en.wikipedia.org/wiki/1I/%CA%BBOumuamua#Non-gravitational_acceleration https://en.wikipedia.org/wiki/1I/%CA%BBOumuamua#Non-gravitat...
- ryanblakeley 1y ago
  There were a number of anomalous characteristics including its shape, acceleration, rotation, origin, and reflectivity.
  - ceejayoz 1y ago
    How do we know they're anomalous characteristics if it's literally the first one we've ever spotted? What is the normal shape of an interstellar comet core?
    - cubefox 1y ago
      For example, being flat like a pancake is obviously highly unusual and very different from anything we have seen from stellar comets.
      - ceejayoz 1y ago
        Stellar comets haven't been ejected from another solar system. We have vanishingly few examples of those, and we've not directly observed any up close. "Flat as a pancake" is one of several theoretical possibilities from its light curve, not a known fact about the object. "Highly unusual" in space tends to mean "there are a bunch, but we haven't seen them until now". In 1992, exoplanets were "highly unusual". Now they're everywhere.
deleted 1y ago
[deleted]
cubefox 1y ago
> It also means that No, it doesn't mean that. What makes 'Oumuamua special is not the fact that we didn't see interstellar objects before. It's rather the fact that 'Oumuamua has highly unusual and hard to explain properties. Avi Loeb: > ‘Oumuamua exhibited a non-gravitational acceleration of 4.92 ± 0.16 × 10^⁻6 m/s² that decreased proportionally to 1/r², where r represents the heliocentric distance, corresponding to a formal ~30 σ detection of non-gravitational acceleration (Micheli et al., 2018). The inverse-square relationship typically indicates radiation pressure or outgassing forces. However, despite extensive observations by the Spitzer Space Telescope, no carbon-based molecules, dust, or thermal emission indicative of cometary outgassing were detected (Trilling et al., 2018). Such a paradox — acceleration without observable mass loss — violates fundamental assumptions about how small bodies behave in the solar system. > The object’s extreme geometry presented another unprecedented observation. ‘Oumuamua’s brightness varied by a factor of 10 during its 8-hour rotation period, indicating an extreme geometry with an aspect ratio exceeding 10:1 (Drahus et al., 2018; Meech et al., 2017). Such extreme elongation is unprecedented among known Solar System objects, leading to competing interpretations of either a cigar-shaped or pancake-like geometry (Belton et al., 2018; Luu et al., 2020; Mashchenko, 2019; Moro-Martín, 2019a,b; Zhang & Lin, 2020). > More significantly, ‘Oumuamua entered the Solar System with a velocity remarkably close to the Local Standard of Rest (LSR). The object’s velocity before encountering the Solar System was within approximately 6 km/s of the local median stellar velocity and just 11 km/s from the LSR, with negligible radial and vertical Galactic motion (Mamajek, 2017). Fewer than 1 in 500 stars share such kinematics, making ‘Oumuamua’s near-stationary approach highly improbable for a naturally ejected object from a nearby star system (Loeb, 2022). Natural ejection mechanisms from planetary systems typically impart the host star’s peculiar velocity to expelled bodies, yet ‘Oumuamua appeared to originate from the most kinematically common frame of reference in our Galactic neighborhood (Loeb, 2022; Mamajek, 2017). > The object’s rotational dynamics added another layer of complexity. ‘Oumuamua displayed non-principal axis rotation, exhibiting a tumbling motion rather than spinning around a single axis. Such a rotational state is unusual for an object that has been traveling through interstellar space for potentially billions of years, as collisions and internal friction should have damped its motion to simple rotation (Belton et al., 2018; Fraser et al., 2018). > Finally, the object’s slightly red color differed from both typical comets and asteroids. Its spectral properties showed no absorption features that would indicate specific mineral compositions, making it difficult to determine its definite surface composition (Jewitt et al., 2017; Ye et al., 2017). This spectral ambiguity prevented researchers from determining surface composition through standard techniques, leaving the object’s fundamental nature — rocky, icy, or something else entirely — unresolved. https://avi-loeb.medium.com/scientific-paradigm-resistance-evidence-from-the-oumuamua-debate-and-cross-disciplinary-cases-c5a4c341a355 https://avi-loeb.medium.com/scientific-paradigm-resistance-e...

api 1y ago

Rendezvous with one of these would be a good use for a NERVA-type nuclear engine (upper stage, not used in the atmosphere). Also seems like the thing to do, given that we are finding more than one of these now, is to build such a thing and have it on standby and look for one that's inbound so we can launch at the best window to reach it.

rtkwe 1y ago
Even with a NERVA engine it's a LOT of work to get to the 26 kmps of an object like ʻOumuamua so you're still at the mercy of planets being in roughly the right locations to provide some gravity assists. I think it would widen the workable solutions but something like the 10 SR assist could work with things we've actually built already.
dylan604 1y ago
to build a thing would be astonishingly lucky for it be parked in the right place to catch the next one, so where would you park it? seems like it would be better to build a lot of them, and park them through out in various orbits so maybe one of them has a chance to rendezvous
- api 1y ago
  I was thinking park it on Earth. Have something ready to launch that consists of a very spicy nuclear upper stage to yeet a small probe at very high speed. The whole upper stages assembly and probe could be sitting there ready to be sent up on a Falcon Heavy or Starship class booster. Might even use an expendable launch to send the upper stage into the highest energy trajectory possible. I wonder how small you could make the probe vs how big the booster and upper stages assembly could be and how fast such a thing could be yeet. I’m thinking even a glorified cubesat size thing paired with a whole lot of rocket. It wouldn’t slow down. It would be a flyby. But it would get us high resolution images and scans and spectroscopic readings, and if one of these visitors was artificial that would become quite obvious with a good picture.

m4rtink 1y ago

Solar Oberth manuever FTW! :D The High Frontier board game from Phil Eklund even has it as a valid option on its orbital map of the Solar system. :)

rtkwe 1y ago
A ten solar radii oberth maneuver too! Which is only slightly farther than the Parker Solar probe got (3.8 million miles vs ~4.3 million for that Lyra proposal)