Voyager 1 and Voyager 2
Two probes that just keep on giving.
NASA has come in for a lot of stick over the years, but yu have to admit - when they build a deep space probe, it stays built!
A pint raised in celebration and thanks.
NASA's Voyager 2, launched to study the Solar System's outer planets, has had its first readings from interstellar space, collected after travelling more than 11 billion miles over forty years, analyzed by scientists. It was the second human-made probe known to have sailed beyond the heliosphere – the expansive region made of …
Bears are just like dogs, they secretly love fireworks! The howling, whimpering and mauling (in the bear case) is just there to make sure we don't catch on!
I'm sure all big firework displays are just there to attract bears into the cities to increase the wildlife diversity in parks!
Bears (Ursids) and Dogs (Canines) form a clade. Which means they are each other’s closest relatives. Like us humans are with chimps.
The next closest relative is the pinnipeds, seals, sealions, dugongs and the like. Meaning they evolved from a dogbear before the dogbear line split into dogs and bears.
Look at a bear and a dog, it doesn’t actually need skeletal comparisons or DNA alignment. Bears are usually bigger than dogs and generally have smaller ears. That’s about it. So a dogbear has middle sized ears and is middle sized or possibly wolf sized (pinnipeds are not small animals either).
I have taken mice apart and know mouse anatomy very well. Grow it, take most of the fur away, shorten the whiskers, flatten the face, move the eyes forward, adjust hand and foot anatomy slightly and you have a hominid. The common ancestor between rodents and primates probably looked a lot like a rodent. Though it’s difficult to tell since we mostly have isolated teeth and occasionally some jaw bone still attached to the teeth from early mammals.
Long ago, I read that in 1895, there were two cars in the state of Ohio. They collided. (Turns out to be almost certainly an urban legend, unfortunately.)
You are correct in thinking that the Roadster is definitely in an elliptical orbit around the sun (perihelion is just inside the earth's orbit, apohelion just outside the orbit of Mars). We have a pretty good idea as to where it is and where it's going, mostly because of amateur astronomers taking images as it went into Outer Darkness and measuring its position. (NASA, ESA, etc. are usually not very interested in heliocentric objects that aren't active payloads.)
I assume we'll someday launch a second car into orbit, and the Roadster will collide with that instead.
Take a bag, throw a loan of magnets into the bag, shake. Notice the magnets all arrange themselves clumped together. Their poles equally can repel and attract, but the force organizes itself to always attract. It is a net attraction only force, lets call this force F2Clumping force.
This force doesn't disappear at cosmological scale, you might suppose it tends to zero if you like to simplify things, but it is *not* zero.
You don't model F2Clumping, you only model gravity as the clumping force, ergo gravity *must* include a component of that force, and gravity is therefore really Sum(F2Clumping, others_stuff).
Look at a photon, it is divisible, it can be split between slits in a slit experiment. So its made of multiple parts. Yet it travels across the universe as a single photon. If those parts were independent, then the tiniest difference would eventually separate them, yet they travel across the universe intact. So there must be a clumping force there too. Lets call that force F1Clumping.
And since gravity is the only clumping force we know, gravity must include that force too, Gravity must be sum(F1Clumping, F2Clumping, other_stuff).
A quick sanity check here, if light has a clumping force, and gravity also has a component that is that clumping force, then light must be bent by gravity. It *is* bent by gravity therefore the sanity check is passed, and gravity must include the F1Clumping force.
And there would be loads of these with matter, notice crystals clumping, notice water clumping notice all *solid* matter clumping to be solid! All of these clumping forces must also be in gravity, since they are small individually but in bulk they are not zero!
So, lets hypothesize a form of gravity as the sum of clumping effects of (for example) an oscillating system at multiples of some resonance frequency. Most of those will be matter oscillating, hence gravity appears to correlate to the measure of matter, "mass".
Gravity = sum(F1Clumping, F2Clumping, F3Clumping, F4WeakClumping, F5Clumping, F6WeakClumping, F7Clumping..... FLimitCaseNearInfinityClumping).
It happens that most of the components of gravity correlate with matter, but not all, the light one for example does not. And we've assigned a magic value to that sum, and this gravitational constant we have assume is due to mass, because most of these clumping effects correlate to mass.
Does gravity bend space? Space is an arbitrary flawed co-ordinate system chosen by humans to define their physics in. Does the universe bend *our* definition? What if Martians have a different definition of space that doesn't need bending (like the one I outlined above), does it bend *our* space and not *their* spacetime?? Is it some sentient being that examines the physics model of the day and bends or does not bend space just for that civilisation to fix up their physics model, based on how crap their understanding of spacetime is?
You see the problem with bent space time? It would be impossible both to bend and not bend space to fix up some physics models not others.
Speed of light in a vacuum isn't a constant, its slower in the vacuum between atoms of glass, than in the vacuum between atoms of air, than in the vacuum between planets. So it's not a constant. We know its not interacting with the atoms of glass individually, because it does not bend further the deeper it goes into the glass. So it is traveling between the atoms in the vacuum between them.
The more spread out the planets the faster light will travel. Our universe is expanding, so the speed of light is getting faster. So the measure of distance "light years" is confused at best.
Hence our definition of space, does not represent any kind of deep understanding of the nature of space, that applies everywhere to everyone. It's badly flawed.
Suppose an electrons size is a sphere, caused by it oscillating over a field. All matter's size is it oscillating over a field.
If the field wavelength was 10 times longer in the X axis than the Y axis, then the electron would be stretched out 10x longer along the X axis than in the Y axis. Matter would be longer in the X axis by a factor of 10. The ruler you measure with, would also be 10x longer in the X axis than the Y axis. And if light is moving ~ 1 wavelength per resonant oscillation, then light is also moving 10x faster in the X axis than the Y axis. And since electric force we make using electrons, and they are oscillating, so electric force is an oscillating force, and it too requires the oscillations to propagate, which is why forces propagate at the apparent same 'speed of light' constant. In this case 10x faster in the X axis than the Y axis.
So you cannot tell if the X axis is 10x longer wavelength than the Y axis. It would always appear to be the same by any measurement you can make.
So our concept of space is a flawed definition based on our local perception of space.
Well done on Voyager guys. There's a lot of bollocks talked about 'wait theory', as if its always better to wait for technology to improve than to start off now. But if you don't start now, there is no driver pushing improvements, and the improvements you are waiting for never happen. You are the driver here. Hats off to ya.
Try reading some real physics, what you cobbled together is misassumptions compounded by misunderstandings resulting in a meaningless word salad.
Far too many errors to address them all, easier to list the bits that are correct:
Err, there does not seem to be any correct bits.
"Look at a photon, it is divisible..."
Wait a sec though... aren't a lot a photonic quantum entanglement experiments based on splitting a single photon into two photons, each with half the energy of the original...? Ergo a photon is "divisible" in some ways.
Just not the ways the OP believes, and this doesn't mean the rest of their... uh... "analysis" (to be generous)... is any less bollocks.
Photons behave differently depending on how you measure them. Fire them singly at a slit and they go through one slit but still interfere. Fire them as a wave and they behave like a wave.
I read an article where they set up a system where they could move from particle to wave and pretty much concluded that whatever a photon is classical ideas of particles and waves do not describe it. Sure you can make it behave like a particle or a wave but that doesn’t mean it is either of those things when you aren’t measuring it.
If you fire a single bollock at a screen with 2 slits in it, you'll get an interference pattern as if it had gone through both.
If you fire multiple bollocks at a screen with 2 slits in it, you get an interference pattern that's unknown until it's observed; at which point it may appear to be a forum post where someone takes a bag and shakes a loan of magnets about...
"Look at a photon, it is divisible, it can be split between slits in a slit experiment. So its made of multiple parts"
It isn't, it can't and it isn't.
Even with my GCSE A level physics from 35 years ago, that sentence made me pause, think and then jump to bit where he said "bollocks", at which point I agreed with him :-)
(I am in awe of this article... the markings on the whiteboard behind the evangelical "physicist"... the reasoning that because we don't fully understand gravity -- which is correct -- it must be God doing everything... definitely one of The Onion's masterpieces.)
Take a bag, throw a loan of magnets into the bag, shake. Notice the magnets all arrange themselves clumped together. Their poles equally can repel and attract, but the force organizes itself to always attract.
There's one fatal flaw in your assumption of a net clumping force: it doesn't exist.
When you put the magnets in a pile (or a bag) some opposite poles will be close enough by chance to attract and stick together; some matching poles will be close enough to repel and that might perhaps move one or both magnets to a point where attraction to another magnet occurs.
By shaking the bag you are providing extra energy the magnets can effectively use to organise themselves -- you're shuffling them around so even at random more opposite poles have the chance to come into contact and connect two magnets together.
If you shook the bag very, very hard the kinetic energy you provided might be enough to overcome the attraction between connected magnets, forcing them through impact to separate. If the bag tears some will have the opportunity to fly apart and never be forced into connecting up again.
Ergo, all your theorising about gravity is just bollocks.
Missed the easy one there.
If you've placed magnets into a bag, the clumping force is attracting them--it's coming from the bag. If you did the same thing with say, glass marbles, they would be clumped at the bottom of the bag as well, as they can't get out of the bag. Using a large (flat) table or the like would be more accurate way to demonstrate 3D space in 2D.
Of course, if you did it without a bag or table, what you'd end up with is just a mess. And then you'd have to clean up all the magnets.
I will admit I was surprised to read that the interstellar medium is higher density then within the solar system. My guess is that when the sun formed it sucked up a lot of the local plasma, dust, etc, and so led to a reduced local density. Although its somewhat surprising that just basic hydrodynamics didnt lead to an "influx" of the high pressure density plasma from the surrouding space to the now lower density pre-solar system. At least up until the point where the sun ignited and started sending out the solar wind to push back against the interstellar medium.
I love when Science throws up curve balls like that and makes you think about your basic assumptions on the universe.
It may be very low density, but the particle soup inside the heliosphere is still a gas, as is the interstellar medium, and the makeup of both is quite similar. Hence the material in both places will obey the physical Gas Laws. The stuff inside the heliosphere is hotter, i.e. contains more energy, than the stuff outside because it has captured more energy from the sun, so it follows that the stuff in the heliosphere must be less dense than the stuff in the interstellar medium.
This hypothesis was proposed some time ago, so its really nice to have two independent measurements that confirm it.
Would centrifugal force have an effect too? The matter inside the star system is pulled around by the host-star's gravity (and other significant bodies such as gas giants), so not only does the matter (plasma and gas) inside the system have a higher energy level, but also a direction that would sweep and push against the interstellar matter. When you swirl water in a bowl the well in the middle is below the resting-state, and against the walls the water rises above the resting-state, trying to push the glass back away from the middle but failing.
> My guess is that when the sun formed it sucked up a lot of the local plasma, dust, etc, and so led to a reduced local density.
The solar system and even the galaxy itself are moving in space so the sun may have sucked up a lot of the local stuff but we're not in that locality any more.
We have plasma streaming out from the Sun at some velocity. the density of the plasma is constantly reducing as it spreads out over a larger area. The momentum of the plasma and the pressure exerted by it is also reducing. If the heliopause represents the boundary where the pressure of interstellar plasma is equal to the solar wind, then unless the interstellar plasma is travelling toward the sun with the same or greater velocity (and lets face it it wont be unless we we closer to some other star), the only way you can have a point where the two pressures are equal and the combined momentum is zero, is if the interstellar medium is more dense. It has to be more dense because the solar wind is travelling at a greater velocity than the interstellar plasma. The solar wind is travelling at a greater velocity away from the Sun than the interstellar plasma is travelling towards the Sun because the solar wind it comes from a star close by, and by comparison the interstellar plasma is likely to be in thermal equilibrium, which will be cooler and thus also more dense than the solar wind, because it has been sitting in interstellar space for billions of years.
The heliosphere is based on solar wind, so why isn't the heliosphere centered around the Sun ? Looking at the diagram, I see a very exaggerated version of Earth's magnetic field. I know the Sun is moving around the center of our galaxy, but surely the heliosphere encounters the pressure of the interstellar medium in all directions, no ?
So why the gigantically-disproportioned tail ?
Think of it like pulling something through water, you will always end up with a long wake trailing behind the boat. The same applies in gases and plasmas, even in the extremely low density of interstellar space.
The proportions in the artists view might be off, but you definitely would see a wake, trailing behind the solar system in its course around the galaxy.... It would be interesting to send out a Voyager 3 in the wake dimension to see just how long the wake is though... NASA hop to it... :)
We do have New Horizons going into interstellar space. A rough extrapolation puts it as far from the sun as Voyager 2 currently is sometime around 2045. Dunno if it's headed in the "wake" direction (and therefore will have to go _really_ far to emerge) or more in the "forward" direction (and therefore wouldn't have to go as far.)
We also have Pioneers 10 and 11, but lost contact with both about fifteen years ago, as they got further away and their Pu-238 decayed. Maybe we just build a bigger radio telescope, suitable for regaining contact? (With the benefit that we can find other things to do with such a telescope.)
Or, to put it another way:
Just remember that you're standing on a planet that's evolving
And revolving at 900 miles an hour.
It's orbiting at 19 miles a second, so it's reckoned,
The sun that is the source of all our power.
Now the sun, and you and me, and all the stars that we can see,
Are moving at a million miles a day,
In the outer spiral arm, at 40, 000 miles an hour,
Of a galaxy we call the Milky Way.
[disclaimer: Monty Python do not guarantee the accuracy of all their lyrics - neither are they peer reviewed.]
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"The two Voyagers will outlast Earth ... They're in their own orbits around the galaxy for five billion years or longer.
As an old contrarian, I am willing to bet my slide rule neither one of the Voyagers will last even 1 billion years. Here is why: As the probes swipe through space, they'll keep colliding with whatever atoms and ions they encounter. The collisions will erode the probes. There isn't a lot of stuff in the interstellar space, but in time the collisions will erode the probes to nothing. We can easily figure out an order of magnitude.
Let's assume the Voyagers are moving at a leisurly pace of 1 km/s through the surrounding medium. Then, in 1 million years they will travel:
1e6 [y/My] * 365 [d/y] * 24 [h/d] * 3600 [s/h] * 1000 [m/s] = 3.2e16 meters.
Assuming that the probes' cross-section is 1 m^2, each will swipe through 3.2e16 m^3 of the interstellar space, and necessarily collide with all the matter therein. Assuming that the interstellar space contains just 1 atom per mililiter (or 1e6 atoms per m^3), that's 3.2e22 atoms, or 0.05 mol. Since most of the matter in the universe is hydrogen, that amounts to 50 milligrams of matter hitting the probe at 1 km/s, each million years. The probes should certainly survive that, and last at least a million years.
However, a billion years is 1000 times longer, and the Voyagers are moving not at 1 km/s, but at over 10 km/s - so in 1 billion years, each will encounter the equivalent of a 500-g [50 mg/My * (10 km/s / 1 km/s) * 1000 My/Gy] projectile hitting it at 10 km/s. They are very unlikely to survive that intact.
A quick JFGI suggests the number of atoms per m^3 is roughly 10. 1e2 rather than 1e6 per m^2.
Are you sure? https://en.wikipedia.org/wiki/Interstellar_medium gives 0.2-0.5 particles/cm^3 - same order of magnitude as my estimate - for both the warm neutral medium and the warm ionized medium, which together account for most of the interstellar space in our galaxy.
On the other hand, a million BBs thrown at a wall with all your might, one at a time, probably won't even scratch the wall. But if you cast all million into a lump and throw it at the wall with the same velocity as you can manage a single BB, you'll hit the wall with the same total energy, but do a good deal more damage.
Gut feeling is the Voyagers will shrug off most of the interstellar matter they come into contact with, just like the wall and the individual BBs.
At 10km/sec the kinetic energy involved in each collision with a hydrogen atom is less than one electron volt. This is not enough to cause an atom to break free from the surface of one of the Voyager probes. The only damage to the surface of the probes would come from heavier particles which are extremely rare compared to hydrogen and helium atoms and from high energy particles (gamma rays and cosmic rays).
What the collisions with the interstellar gas will do is to gradually reduce the relative velocity of the probes and the gas.
Late to this party, but the relative speed is something else to consider. The 10km/s is the Voyagers' speed, but it doesn't take into account the speed of what they collide with.
Those hydrogen atoms could have been hurled at us at near relativistic speeds from a geyser or some other cosmic event, which would give the collision potentially significant energy. I'm no physicist, but I'm guessing this could be interesting to calculate.
Or they might be on similar paths and speeds and lightly bump into each other with extremely low energy.
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His eyes flicked open. He stared straight ahead. Where there should have been the awful white furred face above him, jaws hinging open, or the cold stars spinning slowly as he tumbled, there was instead a familiar figure, hanging upside down from a branch inside a large, brightly lit circular space. He was sitting up in a sort of cross between a bed and a giant nest. He blinked, ungumming his eyes. It did not feel as though it had been blood keeping them shut. He squinted at the creature hanging a few metres in front of him. It blinked and turned its head a little. Praf?' he said, coughing. His throat felt sore, but at least it was properly connected to his head again.
The small, dark creature shook its leathery wings. 'Uagen Zlepe,' it said, 'I am charged with welcoming you. I am 8827 Praf, female. I share the bulk of the memories associated with the fifth-order Decider of the 11th Foliage Gleaner Troupe of the dirigible behemothaur Yoleus which was known to you as 974 Praf, including, it is believed, all those regarding yourself'
Uagen coughed up some fluid. He nodded and looked around. This looked like the interior of Yoleus' Invited Guests' Quarters, with the sub-divisions removed. `Am I back on Yoleus?' he asked.
`You are aboard the dirigible behemothaur Yoleusenive.'
Uagen stared at the hanging creature in front of him. It took him a moment or two to work out the implications of what he'd just heard. He felt his mouth go dry. He swallowed. 'The Yoleus has . . . evolved?' he croaked.
`That is the case.'
He put his hand up to his throat, feeling the tender but whole flesh. He looked slowly up and around. 'How was I,' he began, then had to stop and swallow and start again. 'How was I brought back? How was I rescued?'
`You were found in the without. You wore a piece of equipment which stored your personality. The Yoleusenive has repaired and reconstructed your body and quickened your mind-life within said body.'
'But I wasn't wearing any . . Uagen began, then his voice trailed off as he looked down to where his fingers were stroking the skin around his neck where, once, there had been a necklace.
'the piece of equipment that stored your personality was where your fingers are now,' 8827 Praf confirmed, and clacked her beak once.
Aunt Silder's necklace. He remembered the tiny sting at the back of his neck. Uagen felt tears well in his eyes. 'How much time has passed?' he whispered.
Praf's head tipped to one side again and her eyelids flickered.
Uagen cleared his throat and said, 'Since I left the Yoleus; How much time has passed?'
'Nearly one Grand Cycle.'
Uagen found he could not speak for a little while. Eventually he said, 'One . . . one, ah, galactic, umm Grand Cycle?'
8827 Praf's beak clacked a couple of times. She shook herself, adjusting her dark wings as though they were a cloak. 'That is what a Grand Cycle is,' she said as though explaining something obvious to someone just hatched. 'Galactic.'
Uagen swallowed on a dry, dry throat. It was as though it was still ripped out and open to the vacuum. 'I see,' he said.
I treasure my Ian M Banks books; the world is worse off for his passing
'I am charged with welcoming you. I am 8827 Praf, female. I share the bulk of the memories associated with the fifth-order Decider of the 11th Foliage Gleaner Troupe of the dirigible behemothaur Yoleus which was known to you as 974 Praf, including, it is believed, all those regarding yourself'
^^^ I had a girlfriend like that a long time ago. Nikki? Is it you?
And the probability of them running into anything is almost zero.
I have some problems with that statement, if as is suspected the universe is infinite then unless everything evaporates first then the probability of it hitting something is close to 1:1, it might take a few trillion years but that's nothing when working in astronomical time scales.
And then there's the definition of "something", there's going to be some ablation due to being hit by stray atoms of Hydrogen or Helium or interstellar dust. I suspect they mean "intersecting with another planet" which is a pretty remote chance even on astronomical timescales but there's a lot of other crap floating about for them to bump into.
"it might take a few trillion years but that's nothing when working in astronomical time scales."
Considering that the best scientific estimates we have currently put the Universe at somewhere between 12 - 14 billion years old, then I'd suggest that your "few trillion years" would certainly be SOMETHING in astronomical timescales, rather than the "nothing" you state.
Regardless, I'm fully expecting both of these probes to be either destroyed, or preferably appropriated by some advanced alien race and sent back to us on a fact finding mission. Thinking about it, that would make the basis of a half decent science fiction movi... oh...
In terms of time past since the Big bang then you are quite correct, however in regard to the projected lifetime of the universe a few trillion years is pretty negligible.
Projected death of the Universe is at around 10 qudrodecillion (10^40) years so there's a bit of time left.
Come on folks. While I have been and continue to be a die hard fan of the Voyagers, I do prefer technical accuracy, not blind adoration. A solar system is that volume of space under the direct influence of a central star (or stars - binary system). The Oort Cloud, which envelopes the solar system, is where the Sun drags comets from and therefore is under the influence of the Sun. The Oort Cloud isn't just passing by; it's anchored to the Sun. Stating the heliosphere or the magnetosphere to be the edge of the solar system, as so many do, is simply wrong. The Voyagers have only left the inner region of the solar system and have far to go before reaching, let alone passing through, the Oort Cloud which marks the currently observed edge of the solar system.
The beamwidth of the antenna is enough to be many earth diameters across by the time it hits the earth, so the pointing accuracy doesn't have to be has high as you'd imagine.
With a few assumptions (10GHz, 3.7m dish, 15 billion km away) I reckon that the .25dB beamwidth is about 3000 earth diameters. Link margin is likely to be 1-2dB by now (except for solar conjunctions), so the useable beamwidth might be a bit more than this.
Now, when they start using lasers for space comms then your question is valid, at least for local solar system distances.
".... "It's just astonishing how fluids, including plasmas, form boundaries.""
Really? It happens all the time with liquids and gases here on Earth and it looks like it happens on Sol with plasmas, too. Indeed, it is probably more surprising when bunches of plasmas manage to *mix*.
"Both probes will continue speeding into the depths of the Milky Way galaxy virtually indefinitely."
Only until the Klingons zap one of them in the 22nd Century and the other gets sucked in to a wormhole, evolves into a god and comes back looking for a cuddle and some hugs.
Well, we're all living on borrowed time, are we not, so it's not inconceivable that magnets need to be borrowed for this clumpiness theory to work. ... Or was it a typo: probably should have been "load of magnets" (as in truckload, or as in "load of bollocks"). Gosh this cosmology stuff is fun, you can dream up anything you want to!
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