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Spaceship Oumuamua
Oumuamua is leaving us at high speed.
Humans try to follow it with the VLT, and they report that the thing... is accelerating. Accelerating? When I first saw the drawings I thought: Gosh! This is a spaceship. It really looks like one. Other humans tried to listen if it emits any comprehensible signals. They got nothing in radio frequencies, the only ones we know about. Accelerating? But how? Astronomers put forward the theory of some kind of "outgassing" from its encounter with the sun. Problem is, and they are honest enough to say it, is that no outgassing is seen. The surface of this thing was bombarded by the sun, no problem. But since it is tumbling, there is no preferencial side that gets more illuminated than any any other, and at most, that would produce a dust grain cloud around the object. But that would not furnish any THRUST! Acceleration needs a force vector. The outgassing must be concentrated in one direction to make the desired effect. This thing is moving, i.e. it can change its velocity vector. This a clear sign of life. "Spaceship" is making this thing human-like, and this tumbling object is surely not. But we dreamed of it in our novels and stories. Why? Bceause of the evidence: if we aren't the only ones around, there are beings more advanced than us that can travel around. Is this velocity vector change just the result of random fluctuations of the debris cloud? And why the hypothetical invisible coarse grains that get off the surface of this object (if they exist, as astronomers propose) should have a special direction? The object is tumbling. At least it was tumbling when it passed nearby. And it is quite massive too. Km wide. Accelerating this thing? And accelerating so fast that we can detect it? If we are all serious and agree that spaceships do not exist, we will never see one when it passes by. A pity for us. Oumuamua is leaving us at great speed. Changing its course for new endeavours. jacob [[Mod. note -- Yes, many of us have read "Rendezvous with Rama". But it seems to me that for Oumuamua the "comet-like outgassing" hypothesis is strongly favored by Occam's razor: we know that other objects (comets) outgas in this way (many comets are observed to have non-gravitational accelerations of this type), and if Oumuamua has spent little time near a star it's quite plausible that its surface still has plenty of volatiles (e.g., frozen water and/or methane) which would vaporize (outgas) when heated by a close solar passage. And, unlike Rama, Oumuamua's spin (tumbling) period seems to be a lot longer than 4 minutes. -- jt]] |
#2
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Spaceship Oumuamua
Le 28/06/2018 23:13, jacobnavia a écrit :
Accelerating this thing? And accelerating so fast that we can detect it? If we are all serious and agree that spaceships do not exist, we will never see one when it passes by. A pity for us. Oumuamua is leaving us at great speed. Changing its course for new endeavours. jacob [[Mod. note -- Yes, many of us have read "Rendezvous with Rama". I didn't, that is one novel from Clarke I am missing. But it is fun now that it is the VLT that is bringing the news... A much better novel. Incredible things happen. But it seems to me that for Oumuamua the "comet-like outgassing" hypothesis is strongly favored by Occam's razor: we know that other objects (comets) outgas in this way (many comets are observed to have non-gravitational accelerations of this type), Sure, this thing is outgassing. Comets can do it but... we do not see any outgassing. Strange isn't it? Why not if this is a comet? The "comet/inert rock from other solar system just tumbling around" hypothesis could be true. But the spaceship hypothesis has some traction in it too. and if Oumuamua has spent little time near a star it's quite plausible that its surface still has plenty of volatiles (e.g., frozen water and/or methane) which would vaporize (outgas) when heated by a close solar passage. Sure. But then... we would see it isn't it? We don't. And, unlike Rama, Oumuamua's spin (tumbling) period seems to be a lot longer than 4 minutes. -- jt]] Yes, but that is a detail. The idea behind this post is to discuss in public scientific hypothesis. And the spaceship solution is one of the solutions of this equation. We know its mass, we know its acceleration, how much energy would be necessary to make the observed delta v? We can calculate the tons of material necessary to give the observed thrust isn't it? How much is that? That would be one way of verifying the outgassing hypothesis. How can the spaceship hypothesis be verified? Well, if it is living, it can navigate. We use the mass of Jupiter to point us in the right direction with an added boost. (The new Horizons spaceship for instance). If it is using the mass of the sun to get a boost, as we do, it is accelerating in the direction of its next star. We have just try to figure out where is it moving to. Fun, isn't it? What is this thing? |
#3
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Spaceship Oumuamua
On 6/30/18 4:58 PM, jacob navia wrote:
Le 28/06/2018 23:13, jacobnavia a écrit : Accelerating this thing? And accelerating so fast that we can detect it? If we are all serious and agree that spaceships do not exist, we will never see one when it passes by. A pity for us. Oumuamua is leaving us at great speed. Changing its course for new endeavours. jacob [[Mod. note -- Yes, many of us have read "Rendezvous with Rama". I didn't, that is one novel from Clarke I am missing. But it is fun now that it is the VLT that is bringing the news... A much better novel. Incredible things happen. But it seems to me that for Oumuamua the "comet-like outgassing" hypothesis is strongly favored by Occam's razor: we know that other objects (comets) outgas in this way (many comets are observed to have non-gravitational accelerations of this type), Sure, this thing is outgassing. Comets can do it but... we do not see any outgassing. Strange isn't it? Why not if this is a comet? The "comet/inert rock from other solar system just tumbling around" hypothesis could be true. But the spaceship hypothesis has some traction in it too. and if Oumuamua has spent little time near a star it's quite plausible that its surface still has plenty of volatiles (e.g., frozen water and/or methane) which would vaporize (outgas) when heated by a close solar passage. Sure. But then... we would see it isn't it? We don't. And, unlike Rama, Oumuamua's spin (tumbling) period seems to be a lot longer than 4 minutes. -- jt]] Yes, but that is a detail. The idea behind this post is to discuss in public scientific hypothesis. And the spaceship solution is one of the solutions of this equation. We know its mass, we know its acceleration, how much energy would be necessary to make the observed delta v? We can calculate the tons of material necessary to give the observed thrust isn't it? How much is that? That would be one way of verifying the outgassing hypothesis. How can the spaceship hypothesis be verified? Well, if it is living, it can navigate. We use the mass of Jupiter to point us in the right direction with an added boost. (The new Horizons spaceship for instance). If it is using the mass of the sun to get a boost, as we do, it is accelerating in the direction of its next star. We have just try to figure out where is it moving to. Fun, isn't it? What is this thing? Trying to get a dimensional feel of the problem: Oumuamua's dimensions: 230 x 35 x 35 m = 282,000 m^3 or 2.82x1a^11 cm^3 Assume 1 g/cc density then mass = 2.82x1a^11 g Nature Letter says anomalous non gravity acceleration at 4.92x10^-6 m/sec^2 or 4.92x10^-4 cm/sec^2 Therefore sun based radial Force = 2.82x1a^11 x 4.92x10^-4 = 1.39 x 10^8 dyne Calculate ejected material by impulse momentum F = (m/t) x v with hydrogen ejected at temperature 20 K (perhaps there is a better temperature sqrt(Boltzmann x 20K/hydrogen mass) = 41,000 cm/sec with hydrogen mass ejected on a second basis m/t = F/v = 1.39 x 10^8/41,000 = 3,400 g/sec or 3.4 kg/sec This net radial ejection mass quantity rate does not seem to be that much considering the low temperature gas potential of an object that has been wandering in cold interstellar space for millions of years. Richard D Saam |
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Spaceship Oumuamua
Le 01/07/2018 à 19:37, Richard D. Saam a écrit:
m/t = F/v = 1.39 x 10^8/41,000 = 3,400 g/sec or 3.4 kg/sec OK, but this thing has been accelerating for months... Suppose just 4 months. At this ejection rate we have material=3.4*3600*24*30*4 35 251 200.0 Kg For an object whose mass is 2.82e8 Kg this represents mass=2.82e8 Kg mass/material 7.999727 i.e. this object should have lost 1/8th of its mass in 4 months... And we should somehow see something of those 35 thousand tons of ejected gas. But maybe is not a spaceship, we will never know. There is a recent paper "A possible flyby anomaly for Juno at Jupiter" https://arxiv.org/abs/1711.08893v2 a team of astronomers confirms the pioneer anomaly and other spacecraft mysterious accelerations. Maybe this object is experiencing the same "problem"? That would be also a big scoop, maybe more productive than just an interstellar cargo ship passing by. :-) jacob |
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Spaceship Oumuamua
On 7/2/2018 7:08 AM, jacobnavia wrote:
Le 01/07/2018 à 19:37, Richard D. Saam a écrit: m/t = F/v = 1.39 x 10^8/41,000 = 3,400 g/sec or 3.4 kg/sec ... mass/material 7.999727 i.e. this object should have lost 1/8th of its mass in 4 months... Yes, so after a few passages close to a star it would perhaps be destroyed. But that is what happens to comets and asteroids all the time (assuming that this is just an asteroid). ... But maybe is not a spaceship, we will never know. Maybe we could listen for EM interference with sharply beamed receiver antennas? (Or actually not just noise but intentional radio transmissions.. Has this been investigated?) In any case it is wise of them to disguise their spaceship as an asteroid. And to restrict their acceleration to small values that could be caused by outgassing. That must be quite annoying, never to be able to put their foot on the throttle (I mean their tentacles, of course!) ... a team of astronomers confirms the pioneer anomaly and other spacecraft mysterious accelerations. Maybe this object is experiencing the same "problem"? That would be also a big scoop, maybe more productive than just an interstellar cargo ship passing by. If it is a real asteroid, just hollowed out to carry cargo, it might be the cheapest interstellar transportation method. If it could somehow control its outgassing for course corrections and use a slingshot trajectory, delivering and picking up goods at every passage of a star.. Perhaps Elon Musk should have sent up his Tesla car to Oumuamua! Or better a whole shipment. Primitive artifacts from the natives are always good merchandise. (Although not always a success for the natives.. So maybe the President didn't allow him to, fearing a new trade imbalance would develop?) -- Jos |
#6
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Spaceship Oumuamua
On 7/2/18 12:08 AM, jacobnavia wrote:
Le 01/07/2018 19:37, Richard D. Saam a écrit: m/t = F/v = 1.39 x 10^8/41,000 = 3,400 g/sec or 3.4 kg/sec OK, but this thing has been accelerating for months... Suppose just 4 months. At this ejection rate we have material=3.4*3600*24*30*4 35 251 200.0 Kg For an object whose mass is 2.82e8 Kg this represents mass=2.82e8 Kg mass/material 7.999727 i.e. this object should have lost 1/8th of its mass in 4 months... And we should somehow see something of those 35 thousand tons of ejected gas. But maybe is not a spaceship, we will never know. There is a recent paper "A possible flyby anomaly for Juno at Jupiter" https://arxiv.org/abs/1711.08893v2 a team of astronomers confirms the pioneer anomaly and other spacecraft mysterious accelerations. Maybe this object is experiencing the same "problem"? That would be also a big scoop, maybe more productive than just an interstellar cargo ship passing by. :-) jacob My apologies, I made a mistake length m^3 cm^3 conversion The ejection rate .034 kg/sec and not 3.4 kg/sec ***************** Trying to get a dimensional feel of the problem: Oumuamua's dimensions: 230 x 35 x 35 m = 282,000 m^3 or 2.82x10^9 cm^3 Assume 1 g/cc density then mass = 2.82x10^9 g Nature Letter says anomalous non gravity acceleration at 4.92x10^-6 m/sec^2 or 4.92x10^-4 cm/sec^2 Therefore sun based radial Force = 2.82x10^9 x 4.92x10^-4 = 1.39 x 10^6 dyne Calculate ejected material by impulse momentum F = (m/t) x v with hydrogen ejected at temperature 20 K (perhaps there is a better temperature sqrt(Boltzmann x 20K/hydrogen atomic weight) = 41,000 cm/sec with hydrogen mass ejected on a second basis m/t = F/v = 1.39 x 10^6/41,000 = 34 g/sec or .034 kg/sec This net radial ejection mass quantity rate does not seem to be that much considering the low temperature gas potential of an object that has been wandering in cold interstellar space for millions of years. Richard D Saam |
#7
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Spaceship Oumuamua
On 30/06/2018 22:58, jacob navia wrote:
Le 28/06/2018 23:13, jacobnavia a écrit : Accelerating this thing? And accelerating so fast that we can detect it? If we are all serious and agree that spaceships do not exist, we will never see one when it passes by. A pity for us. Oumuamua is leaving us at great speed. Changing its course for new endeavours. jacob [[Mod. note -- Yes, many of us have read "Rendezvous with Rama". I didn't, that is one novel from Clarke I am missing. But it is fun now that it is the VLT that is bringing the news... A much better novel. Incredible things happen. If we see another two go past then we will know that ET is a big fan of Arthur C. Clarke. But it seems to me that for Oumuamua the "comet-like outgassing" hypothesis is strongly favored by Occam's razor: we know that other objects (comets) outgas in this way (many comets are observed to have non-gravitational accelerations of this type), Sure, this thing is outgassing. Comets can do it but... we do not see any outgassing. Strange isn't it? It is probably a bit far from the sun now to see if there is any coma. Why not if this is a comet? It may be a comet with a nice sturdy thick crust of black sooty dust on the surface and the heat from the sun has finally reached a volatile layer deep inside it. The anomolous acceleration isn't really anything to write home about - merely that it isn't slowing down in exactly the way that basic gravitational mechanics would predict. The "comet/inert rock from other solar system just tumbling around" hypothesis could be true. But the spaceship hypothesis has some traction in it too. and if Oumuamua has spent little time near a star it's quite plausible that its surface still has plenty of volatiles (e.g., frozen water and/or methane) which would vaporize (outgas) when heated by a close solar passage. Sure. But then... we would see it isn't it? We don't. And, unlike Rama, Oumuamua's spin (tumbling) period seems to be a lot longer than 4 minutes. -- jt]] ISTR Rama was spinning along the central axis allowing fake gravity on the inside rim. And they did everything in threes. [snip] If it is using the mass of the sun to get a boost, as we do, it is accelerating in the direction of its next star. We have just try to figure out where is it moving to. Fun, isn't it? What is this thing? That is an interesting question though. Did the approach trajectory look planned to take advantage of the position of any of the gas giants to get a slingshot assist? That *would* favour ET being involved. -- Regards, Martin Brown |
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Spaceship Oumuamua
On Mon, 02 Jul 2018, Martin Brown wrote:
That is an interesting question though. Did the approach trajectory look planned to take advantage of the position of any of the gas giants to get a slingshot assist? That *would* favour ET being involved. For interstellar travel, the Sun itself can be used for a slingshot assist for (say) travelling outwards in the Galactic disk. The key question, I think, is whether the object approached on a similar vector as the Sun's but travelling a bit faster so as to catch up to the Sun.. |
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Spaceship Oumuamua
On 6/28/18 11:13 PM, jacobnavia wrote:
The object is tumbling. At least it was tumbling when it passed nearby. And, unlike Rama, Oumuamua's spin (tumbling) period seems to be a lot longer than 4 minutes. -- jt]] Yes, interstellar originated Oumuamua's spin (tumbling) period is faster than Rama's 4 minutes and has a ~8 hr spin commonality with a lot of asteroids. Is that a coincidence? Or how about a similar period observed by gravitationally sensitive Pathfinder and Gravity Probe B (outside their stated missions). And then there are universal stellar core g-waves of the same period. It all points to a universal Machian oscillation. Is it alive? That is the question. Richard D Saam |
#10
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Spaceship Oumuamua
On 7/9/2018 8:42 PM, Eric Flesch wrote:
On Mon, 02 Jul 2018, Martin Brown wrote: That is an interesting question though. Did the approach trajectory look planned to take advantage of the position of any of the gas giants to get a slingshot assist? That *would* favour ET being involved. For interstellar travel, the Sun itself can be used for a slingshot assist for (say) travelling outwards in the Galactic disk. The key question, I think, is whether the object approached on a similar vector as the Sun's but travelling a bit faster so as to catch up to the Sun.. The key question for the slingshot hypothesis is whether it comes from the direction of a nearby star and leaves the solar system into the direction of another nearby star. If both directions would match a star within, say 100 psc distance, then it is a slingshot trajectory for traveling along three stars. (By definition it is such a trajectory, whether it is *intentionally* so, or just by accident, is then still not proven. but one could calculate how small the chances for the latter would be..) Of course one could always match the two directions to very distant stars, but then there is a big chance that it is accidental. There are 2 'uncertainty cones' around the measured directions of arrival and departure and we could ask: What are the nearest stars in those two cones and how small (or big) is the combined chance of finding them at those distances. [And if nobody has published the result of that calculation yet, that fact is of course good material for a conspiracy theory! :-) ] -- Jos |
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