Anyone who thinks that Facebook can't tell the difference between someone checking in through the web client or even checking in through the app by putting in a location instead of actually geolocating is a dumbshit.
Doesn't Android in it's development modes have an option for faking (overriding) the location returned by the GPS sub-system. So unless Facebook directly talks to the hardware (don't know - never used the app when I had a FB account), they shouldn't be able to know if that's happening.
Of course, the absence of "jitter" in the last couple of decimal places would still give it away. Unless the "developer modes" cover that too. Having met software that will fake data including different error/ noise models, I wouldn't be surprised either way.
But the most profound observation I have ever made was seeing the look on a youngster's face after he had directly viewed the moons of Jupiter for the first time. That is the most significant use of a telescope that I have ever done, and I would like to repeat it.
There's a guy does that in a corner of Fountain Square (which isn't square, but does have fountains) in Baku. Nice guy. Speaks about 3 more words of English than I do (or did, then) of Russian.
Traveling through through space containing the typical atom of interstellar hydrogen per cm^3 at relativistic speeds(0.95C) would result in instant death.
That's a fairly dense molecular cloud, rather than a typical interstellar medium. But the general point is still valid - at relativistic velocities, stationary material is dangerous.
No, we don't have any technologies that can protect against this material, particularly neutral material.
The most obvious missing cause is "our particular G0 star is unusual".
Which, considering that almost every natural phenomenon has multiple ways of being measured, almost al of which have significant variance, is likely to be true for almost every natural phenomenon. Any particular specimen is likely to be unusual in some way.
Which anyone who has tried to identify a fossil (part of my day job) or a tree, or a piece of pond-slime (my activity precisely one email ago) will know already.
Nice way of putting it. I might not agree with the premise, but it certainly bears thinking about. Until you realise there's X light years between "them" and "us".
Very interesting, thanks. So where did this proposed planetary mass come from?
The Brown-Batygin Planet 9 (there are other proposals), at about 10 Earth-masses (~= 0.03 Jupiter masses), is proposed as a primordial part of the solar system, possibly with it's perihelion raised by interactions with the gas giants (i.e. Jupiter and it's sidekick Saturn, sideline-cheering from Neptune and Uranus) during the 500-700 million years (after origin of the Solar system) of re-shuffling which the inner planets saw as the "Late Heavy Bombardment". Their estimates (published in about March this year IIRC - the papers are on Arxiv) suggest that such a planet may remain visible in the IR - just - and they're just conducted an observing campaign in Hawaii which I assume was targetting just this hypothesis. In fact (fiddles with Skyglobe), just from the clock and the observatory, you can deduce that they're looking at RAs of 07 to about 21H. (Don't ask me to convert that into solar longitudes in my head!)
BTW, love your tagline... puts birds in a new perspective.
It's intended to. But it's probably 5 years since I've changed it. It's as subtle as an ostrich beak to the gonads (an experience to be avoided, according to the only one-eyed man I know who has had the experience).
With the information I gave you, your estimate of my age was a good one.
I put a good few minutes (and edits) into working it out.
My facts were wrong.
You're a bolder person than most Slashdotters for being able to admit it.
Thoughts on "one of the computer-controlled" scopes : one of my colleagues who has better skies than me for practical astronomy brought a little Meade "goto"scope about a dozen years ago (ETX-80 or ETX-90, I forget ; whichever came first), liked it a lot, and upgraded after a couple of years to the 125mm (4in~) version which he also likes. That and a decent tripod, a few fittings and he's routinely turning out cloud photos (noctilucents in particular), air-show photos, and occasional lunar photos that he's very happy with.
On the basis of that experience, I'd decided that if I did buy such a scope, I'd go direct for the 125mm version.
But I suspect that I'd get more productive use from an account with a Pro-Am telescope that is operated over the Internet. I really should look at that again - not really followed up on it since my last bout of consideration last year.
However, the reductio ad absurdam is that if you don't have a criterion for differentiating between a star, a planet, and a minor body (dwarf planet, mote, dust, asteroid, whatever), then you shove lots of different bodies into one classification. Kind of like including dolphins and whales as "fish" because they live in the sea and aren't worms.
From my geologist's point of view, I'd probably have been happier with the dividing line being put at the "forms a sphere under self-gravity", but I'm a geologist not an astronomer and haven't put in the 20-odd years of research work to have had an invite to the IAU bun-fest and had a vote. And I'm content with the criteria that they've developed, whereas the criterion I suggest would have put Pluto at around planet #20 at it's time of discovery.
The solar system is not old enough - by billions or tens of billions of years - for a brown dwarf which formed at the same time as the rest of the solar system to have cooled to the point that recent decades of whole-sky IR surveys couldn't see it. Even planets as small as the Brown-Batygin proposal for Planet 9 (~10*Earth-mass) would have noticeable IR emission.
(One of the weirder things about Jupiter mass and larger planets is that their diameter and therefore surface area and therefore heat-loss rate changes little between Jupiter mass and deuterium-ignition mass @ ~75 Jupiter-mass. So loss of heat-of-formation takes longer than you'd expect.)
For the solar system to have captured a cold brown dwarf (or black dwarf, or Jupiter mass planet, or even a back hole ; why not ; the only relevant factor is mass) between the stabilisation of plantary orbits at around 1 billion years after origin and today, there would have been a massive disruption of the inner and outer solar system as the interloper passed through to where it would need to mutually interact with the Sun and some other large body. You need the third body to take angular momentum and energy out of the system, otherwise the interloper will leave the system after it's inelastic (energy conserving) interaction with the Sun. This is a result that was worked out in the 18th or 19th century, by hand, as people tried to work out the implications of Laplace's proposed methods for origin of the solar system.
Sorry, but the Solar system is pretty boring. OTOH, if it weren't a boring place, we'd probably have died out before getting an oxygenated atmosphere.
It's not like you go through a metal detector or are waved for bugs.
Yet.
I'm assuming that US polling places already have metal detectors due to the threat of armed nut jobs attacking them on polling day. If not this election, then the next one. Soldiers in full battle gear outside the polling places too, yet? To protect the populace and provide a little more security theatre.
You can get an air pistol, or a rifle, but not a handgun.
Air weapons are being tightened up on - a lot. Since it doesn't affect me, I didn't note any great details, but the last time I was in a cop shop they had a locked container chained up outside covered in posters about the amnesty for people to surrender their air weapons before the licensing requirement comes into effect. From which I deduce that in the near future, possessing an unlicensed air weapon will become an offence.
We Travel through a Crowded Galaxy... and pass close to other stars. Furthermore the Sun probably evolved in a densely packed globular cluster.
Not a globular cluster. They're a different cluster of stars. Probably the Sun did form in a molecular cloud with many others - see for example, the modern Orion star-forming region. The light from the largest and brightest of the cluster's stars would then have dispersed the remaining gas and dust of the cloud (see both the Orion nebulae and the "Pillars of Creation" photo done by Hubble), eventually leaving an open cluster (see Pleiades, or Praesepe - the Beehive Cluster). And eventually, the cluster would have dispersed to the barely detectable (such as the
Astronomers are looking for stars of the same age, chemistry and motions as the Sun, as potential stars formed in the same molecular cloud. But TTBOMK, they haven't found an example.
Since formation, the Sun - and it's cohort - will have orbited the galaxy on the order of 20 times. So even small initial relative motions would have thoroughly dispersed them by now.
All of which is a typology of different types of stellar cluster. But globular clusters are a different beast, not on that typology.
I believe it was first seen by a comet hunter. So that was a happy accident.
Your memory is faulty, or your original sources were incorrect. Pluto was discovered as the result of a multi-year search programme by the Lowell Observatory, looking for Pluto using calculations made by it's founder (and funder), Lowell. Clyde Tombaugh was hired by the observatory as an observer, and specifically assigned to perform this task. It was as accidental as something completely intentional.
People certainly tried to predict the existence of both Neptune and later Pluto from discrepancies in the orbits of inner planets. And while this approach has the potential to work, it remains unclear if either of the discoveries were more than coincidence. Tombaugh performed a comprehensive search of the anti-solar point, which scans the entire sky once per year (obviously). This covered the areas which Lowell predicted, and a lot of other sky too. By putting the hoped-for object in the darkest sky, the odds of detection are improved.
Charon had nothing to do with the discovery of Pluto. However, Charon's discovery did finally allow the mass of Pluto (and Charon) to be determined accurately for the first time, finding it to be around 1/1000 of earlier estimates.
To have been taught about the discovery of Pluto 3-4 decades before the discovery of Charon, you'd be remembering things you were taught between 1938 and 1948, putting you in your 90s, and possibly the oldest Slashdot reader I've commented to. What did you do in the War?
Has there ever been any evidence that this was once a binary system?
None. The Sun matches the behaviour of similarly massed stars very closely. While about half of all stars are in multiples (and so about 1/3 of star systems are multiple), no evidence of the Sun having a companion star has been reported.
If a putative companion were comparable in size to the Sun, than we'd see it by night. In fact, we'd not really have a night. (ACC played with that in one of the Space Odyssey sequels, IIRC)
If th putative companion were smaller than the Sun, it'd have to be considerably smaller to not be obvious. Smaller stars develop more slowly and last for longer, so it would still be visible. That relation lasts all the way down to the bottom end of "stars" at around 80 Jupiter-masses, when we get into the brown dwarfs. And even for them, we can model the evolution of temperature (from heat released on formation from infalling material) against time, and say "there isn't anything bright enough out there". (We do have adequate whole-sky IR surveys.)
Get down to Jupiter-mass and smaller (Brown-Batygin propose a Planet 9 of around 10 Earth masses/ 1 Neptune mass/ 0.03 Jupiter mass) and the temperatures and luminosities continue to decrease, but remain potentially observable (Brown has recently been complaining about the weather on Hawaii, blinding his telescope time looking for exactly this). Unfortunately, there are other similar-looking sources on the sky, at greater distances than the putative Planet 9, which is going to complicate interpretation of the data.
Astronomers do not reject the idea of "the Sun's companion", "Niburu", or whatever you want to call it out of caprice, malice to SF authors, or because their Mufti tells them to. The hypothesis has been rejected because observational evidence that should be visible if the hypothesis were correct has been looked for and is not there.
The answer seems to be that the planets' orbital plane, the ecliptic, is tilted.
It's worse than that. "THE ecliptic" is the projection of the Earth's orbit onto the plane of the sky as seen from the centre of the Sun. Or (equivalently), the projection of the Sun's position onto the plane of the sky from the Earth.
For every object in orbit around the Sun, there is a different ecliptic, similarly defined. We relate them to the Earth-Sun ecliptic purely for the convenience that we are mostly resident on Earth.
Now consider a particle on the Sun's equator, which for some completely incomprehensible reason (let's call it the Noodly Appendage) sits exactly stationary (whatever that means). As seen from the centre of mass of the Sun, it will trace a line on the plane of the sky in the same way as the ecliptics discussed above. That plane is not coincident with the Earth-ecliptic, nor with any of the other planet's respective ecliptics. They do cluster on the plane of the sky - within about 6 degrees as seen from the centre of mass of the Solar System - but they are not coincident. Add Pluto - 17 degrees spread now. Add Planet 9... 25 to 30 degrees.
Until recently, planet hunting took place on that 6 degree band. Pluto's discovery tripled the size of the search area. Planet 9 increases it around 6-fold again.
The problem here is that Planet X is so far away, and its orbit is so long, that you would need to observe the sun for thousands of years for the movement to be discernible.
This might work, if the output of the Sun was stable over that period of time. We don't know that.
IANAA but I have an impractical idea that might work. Everything outside solar system is either redshifted or blueshifted by a large margin.
Your last sentence which I quote is where it breaks down. Not everything outside the solar system is considerably red- or blue-shifted w.r.t laboratory standards (at zero relative velocity). Most things that we can see in our galaxy have very little velocity relative to us, because most of the galaxy is invisible to us due to dust and gas in the plane of the galaxy. It's easier to see 10 million light years out of the galactic plane than to see a couple of thousand light years in the plane of the galaxy.
Say that we look towards the galactic centre. Since we're in a nearly circular orbit around the centre of mass of the galaxy, our velocity relative to it is nearly zero. The same applies for any other objects near our radial line from th centre of mass of the galaxy.
Nearby objects ahead of us and behind us in our orbits are also in near-circular orbits, and also have consequently low relative velocities.
And that is assuming it's a bright object reflecting a LOT of light from a very distant sun. If this thing is dark in color at all, the lumens available out at where they guess it is...
The best chance - if you read the papers - is in the fairly far IR, looking for remenant heat of formation from the assembly of the planet. If I remember the papers, which I did read.
It has all been put up on Arxiv, and no small amount of it submitted to this site as news items.
Slashdot Mirror
Doesn't Android in it's development modes have an option for faking (overriding) the location returned by the GPS sub-system. So unless Facebook directly talks to the hardware (don't know - never used the app when I had a FB account), they shouldn't be able to know if that's happening. Of course, the absence of "jitter" in the last couple of decimal places would still give it away. Unless the "developer modes" cover that too. Having met software that will fake data including different error/ noise models, I wouldn't be surprised either way.
There's a guy does that in a corner of Fountain Square (which isn't square, but does have fountains) in Baku. Nice guy. Speaks about 3 more words of English than I do (or did, then) of Russian.
That's a fairly dense molecular cloud, rather than a typical interstellar medium. But the general point is still valid - at relativistic velocities, stationary material is dangerous.
No, we don't have any technologies that can protect against this material, particularly neutral material.
I take it that you'll be holding yourself down and beating yourself to death, to save us the effort?
Which, considering that almost every natural phenomenon has multiple ways of being measured, almost al of which have significant variance, is likely to be true for almost every natural phenomenon. Any particular specimen is likely to be unusual in some way.
Which anyone who has tried to identify a fossil (part of my day job) or a tree, or a piece of pond-slime (my activity precisely one email ago) will know already.
s/ scientists/ politicians/
Scientists can be as interested as they want in $SOMETHING$, but if no one will pay for it, it ain't going to happen.
Nice way of putting it. I might not agree with the premise, but it certainly bears thinking about. Until you realise there's X light years between "them" and "us".
The Brown-Batygin Planet 9 (there are other proposals), at about 10 Earth-masses (~= 0.03 Jupiter masses), is proposed as a primordial part of the solar system, possibly with it's perihelion raised by interactions with the gas giants (i.e. Jupiter and it's sidekick Saturn, sideline-cheering from Neptune and Uranus) during the 500-700 million years (after origin of the Solar system) of re-shuffling which the inner planets saw as the "Late Heavy Bombardment". Their estimates (published in about March this year IIRC - the papers are on Arxiv) suggest that such a planet may remain visible in the IR - just - and they're just conducted an observing campaign in Hawaii which I assume was targetting just this hypothesis. In fact (fiddles with Skyglobe), just from the clock and the observatory, you can deduce that they're looking at RAs of 07 to about 21H. (Don't ask me to convert that into solar longitudes in my head!)
It's intended to. But it's probably 5 years since I've changed it. It's as subtle as an ostrich beak to the gonads (an experience to be avoided, according to the only one-eyed man I know who has had the experience).
I put a good few minutes (and edits) into working it out.
You're a bolder person than most Slashdotters for being able to admit it.
Thoughts on "one of the computer-controlled" scopes : one of my colleagues who has better skies than me for practical astronomy brought a little Meade "goto"scope about a dozen years ago (ETX-80 or ETX-90, I forget ; whichever came first), liked it a lot, and upgraded after a couple of years to the 125mm (4in~) version which he also likes. That and a decent tripod, a few fittings and he's routinely turning out cloud photos (noctilucents in particular), air-show photos, and occasional lunar photos that he's very happy with.
On the basis of that experience, I'd decided that if I did buy such a scope, I'd go direct for the 125mm version.
But I suspect that I'd get more productive use from an account with a Pro-Am telescope that is operated over the Internet. I really should look at that again - not really followed up on it since my last bout of consideration last year.
However, the reductio ad absurdam is that if you don't have a criterion for differentiating between a star, a planet, and a minor body (dwarf planet, mote, dust, asteroid, whatever), then you shove lots of different bodies into one classification. Kind of like including dolphins and whales as "fish" because they live in the sea and aren't worms.
From my geologist's point of view, I'd probably have been happier with the dividing line being put at the "forms a sphere under self-gravity", but I'm a geologist not an astronomer and haven't put in the 20-odd years of research work to have had an invite to the IAU bun-fest and had a vote. And I'm content with the criteria that they've developed, whereas the criterion I suggest would have put Pluto at around planet #20 at it's time of discovery.
(One of the weirder things about Jupiter mass and larger planets is that their diameter and therefore surface area and therefore heat-loss rate changes little between Jupiter mass and deuterium-ignition mass @ ~75 Jupiter-mass. So loss of heat-of-formation takes longer than you'd expect.)
For the solar system to have captured a cold brown dwarf (or black dwarf, or Jupiter mass planet, or even a back hole ; why not ; the only relevant factor is mass) between the stabilisation of plantary orbits at around 1 billion years after origin and today, there would have been a massive disruption of the inner and outer solar system as the interloper passed through to where it would need to mutually interact with the Sun and some other large body. You need the third body to take angular momentum and energy out of the system, otherwise the interloper will leave the system after it's inelastic (energy conserving) interaction with the Sun. This is a result that was worked out in the 18th or 19th century, by hand, as people tried to work out the implications of Laplace's proposed methods for origin of the solar system.
Sorry, but the Solar system is pretty boring. OTOH, if it weren't a boring place, we'd probably have died out before getting an oxygenated atmosphere.
Well ... actually, you just did.
Yet.
I'm assuming that US polling places already have metal detectors due to the threat of armed nut jobs attacking them on polling day. If not this election, then the next one. Soldiers in full battle gear outside the polling places too, yet? To protect the populace and provide a little more security theatre.
Sure will. Which knee do you never want to bear weight again?
Young little shits like you would have been better as a spat-out blow job instead of being wasted on an ovum.
Spaghetti for supper, I think.
Air weapons are being tightened up on - a lot. Since it doesn't affect me, I didn't note any great details, but the last time I was in a cop shop they had a locked container chained up outside covered in posters about the amnesty for people to surrender their air weapons before the licensing requirement comes into effect. From which I deduce that in the near future, possessing an unlicensed air weapon will become an offence.
Signed, Felix.
(After minor planet 1664 Felix (1929 CD), discovered February 4, 1929 by E. Delporte ; the last Solar system body discovered before Pluto, TTBOMK).
Yes, this is an example of reductio ad absurdam .
Not a globular cluster. They're a different cluster of stars. Probably the Sun did form in a molecular cloud with many others - see for example, the modern Orion star-forming region. The light from the largest and brightest of the cluster's stars would then have dispersed the remaining gas and dust of the cloud (see both the Orion nebulae and the "Pillars of Creation" photo done by Hubble), eventually leaving an open cluster (see Pleiades, or Praesepe - the Beehive Cluster). And eventually, the cluster would have dispersed to the barely detectable (such as the
) before dispersing beyond the detectable.
Astronomers are looking for stars of the same age, chemistry and motions as the Sun, as potential stars formed in the same molecular cloud. But TTBOMK, they haven't found an example.
Since formation, the Sun - and it's cohort - will have orbited the galaxy on the order of 20 times. So even small initial relative motions would have thoroughly dispersed them by now.
All of which is a typology of different types of stellar cluster. But globular clusters are a different beast, not on that typology.
Your memory is faulty, or your original sources were incorrect. Pluto was discovered as the result of a multi-year search programme by the Lowell Observatory, looking for Pluto using calculations made by it's founder (and funder), Lowell. Clyde Tombaugh was hired by the observatory as an observer, and specifically assigned to perform this task. It was as accidental as something completely intentional.
People certainly tried to predict the existence of both Neptune and later Pluto from discrepancies in the orbits of inner planets. And while this approach has the potential to work, it remains unclear if either of the discoveries were more than coincidence. Tombaugh performed a comprehensive search of the anti-solar point, which scans the entire sky once per year (obviously). This covered the areas which Lowell predicted, and a lot of other sky too. By putting the hoped-for object in the darkest sky, the odds of detection are improved.
Charon had nothing to do with the discovery of Pluto. However, Charon's discovery did finally allow the mass of Pluto (and Charon) to be determined accurately for the first time, finding it to be around 1/1000 of earlier estimates.
To have been taught about the discovery of Pluto 3-4 decades before the discovery of Charon, you'd be remembering things you were taught between 1938 and 1948, putting you in your 90s, and possibly the oldest Slashdot reader I've commented to. What did you do in the War?
None. The Sun matches the behaviour of similarly massed stars very closely. While about half of all stars are in multiples (and so about 1/3 of star systems are multiple), no evidence of the Sun having a companion star has been reported.
If a putative companion were comparable in size to the Sun, than we'd see it by night. In fact, we'd not really have a night. (ACC played with that in one of the Space Odyssey sequels, IIRC)
If th putative companion were smaller than the Sun, it'd have to be considerably smaller to not be obvious. Smaller stars develop more slowly and last for longer, so it would still be visible. That relation lasts all the way down to the bottom end of "stars" at around 80 Jupiter-masses, when we get into the brown dwarfs. And even for them, we can model the evolution of temperature (from heat released on formation from infalling material) against time, and say "there isn't anything bright enough out there". (We do have adequate whole-sky IR surveys.)
Get down to Jupiter-mass and smaller (Brown-Batygin propose a Planet 9 of around 10 Earth masses/ 1 Neptune mass/ 0.03 Jupiter mass) and the temperatures and luminosities continue to decrease, but remain potentially observable (Brown has recently been complaining about the weather on Hawaii, blinding his telescope time looking for exactly this). Unfortunately, there are other similar-looking sources on the sky, at greater distances than the putative Planet 9, which is going to complicate interpretation of the data.
Astronomers do not reject the idea of "the Sun's companion", "Niburu", or whatever you want to call it out of caprice, malice to SF authors, or because their Mufti tells them to. The hypothesis has been rejected because observational evidence that should be visible if the hypothesis were correct has been looked for and is not there.
It's worse than that. "THE ecliptic" is the projection of the Earth's orbit onto the plane of the sky as seen from the centre of the Sun. Or (equivalently), the projection of the Sun's position onto the plane of the sky from the Earth.
For every object in orbit around the Sun, there is a different ecliptic, similarly defined. We relate them to the Earth-Sun ecliptic purely for the convenience that we are mostly resident on Earth.
Now consider a particle on the Sun's equator, which for some completely incomprehensible reason (let's call it the Noodly Appendage) sits exactly stationary (whatever that means). As seen from the centre of mass of the Sun, it will trace a line on the plane of the sky in the same way as the ecliptics discussed above. That plane is not coincident with the Earth-ecliptic, nor with any of the other planet's respective ecliptics. They do cluster on the plane of the sky - within about 6 degrees as seen from the centre of mass of the Solar System - but they are not coincident. Add Pluto - 17 degrees spread now. Add Planet 9 ... 25 to 30 degrees.
Until recently, planet hunting took place on that 6 degree band. Pluto's discovery tripled the size of the search area. Planet 9 increases it around 6-fold again.
It's a big problem.
This might work, if the output of the Sun was stable over that period of time. We don't know that.
Your last sentence which I quote is where it breaks down. Not everything outside the solar system is considerably red- or blue-shifted w.r.t laboratory standards (at zero relative velocity). Most things that we can see in our galaxy have very little velocity relative to us, because most of the galaxy is invisible to us due to dust and gas in the plane of the galaxy. It's easier to see 10 million light years out of the galactic plane than to see a couple of thousand light years in the plane of the galaxy.
Say that we look towards the galactic centre. Since we're in a nearly circular orbit around the centre of mass of the galaxy, our velocity relative to it is nearly zero. The same applies for any other objects near our radial line from th centre of mass of the galaxy.
Nearby objects ahead of us and behind us in our orbits are also in near-circular orbits, and also have consequently low relative velocities.
How are these probes of yours going to know their position in space in order to report it back?
Just a little question. A tiny little question. A really simple, basic, fundamental question. Got an answer?
The best chance - if you read the papers - is in the fairly far IR, looking for remenant heat of formation from the assembly of the planet. If I remember the papers, which I did read.
It has all been put up on Arxiv, and no small amount of it submitted to this site as news items.