why does Dutch, UK have the authority to issue fines?
The UK has nuclear weapons. Some of them are probably in United States (or Canada) territorial waters, with sufficient range to hit many (most) million plus cities in the contiguous US.
Is that sufficient reason. (I assume that the Trumpian concept that "international law has no meaning" has already been hung from a tree in the finest lynching style. TrÃs American!)
About the same as 4 billion years ago, and 5 billion years ago - every year around 3 solar masses of interstellar medium were turned into stars, most of which were red dwarfs (and still are) though a couple of times a decade a star with a sun-like mass gets made. More rarely, larger stars would get formed.
TFA has no implication that anything particularly unusual was happening then. At this moment, the portion of the Milky Way visible to us (maybe one tenth of it), has several hundred open clusters of the form which they are suggesting the Sun and HD186302 once shared.
You : Mars had liquid water (and may still, underground), and several moons have liquid water under the surface
These are
GP : planets with abundant LIQUID surface water
??
There is a problem of coverage here. Out of the relatively small areas of the sky surveyed, to a quite shallow depth of survey, with major biases towards non-Sun-like stellar systems in the search methods, we have not found an Earth-a-like.
But we have found a number of somewhat similar systems.
And there are literally billions of un-surveyed systems in the galaxy.
While we haven't found an Earth-alike system, it's fairly safe to conclude that they are out there. It's as unsure as the prevalence of unfocussed video cameras and gorilla suits in Oregon being a good predictor of at least one Bigfoot hoaxer in America.
I make that about 7000 miles/ year on average dispersion velocity. I've had cars that travel faster than that. Actually, I don't think I've had a car which didn't travel faster than that, on average, over a year.
Taking you seriously, humans - and all other mammals - are fish. In the sense that we are craniate vertebrates and not sharks. Not all fish live in the sea. Some fish fly better than humans.
For those who don't know, the family of plants that includes the grasses - including all of our major calorie crops - evolved in the Eocene, some 15 to 20 million years after the end of the Cretaceous.
It would have effects, agreed. But having worked from the Bristol Channel (second highest tidal range in the world, after Bay of Fundy) to the Mediterranean (negligible tidal range), I'm really unclear as to which is "better", and which is "messed with"? Could you elaborate on why one is better than the other - or do you just mean "different to what I'm used to EQUALS worse"?
we can use that to add some spin to the moon, instead of keeping it tidally locked to earth.
Firstly, you'd have to concentrate the damage into one relatively small area, which is going to make a deep hole.
Secondly, the Moon's rotational locking to it's orbit around the Earth is considerably helped by the centre-of-mass of the Moon being displaced by some 60km from it's centre-of-figure towards the Earth. That's a characteristic that seems to have been inherited from the "magma ocean phase of the formation of the Moon - the first few thousand years (maybe approaching a million?) after the Moon formed.
The moon would require roughly 1,000 comets to terraform.
Care to show some working to go with that? I'm getting more like a million. Oh, sorry, that's for Mars - so on the order of 30,000 comets for the Moon. Not that it would hold onto the vapour for more than a few days.
We'll need to develop the habitats anyway, as work camps for collecting the volatile-rich asteroids to deliver a workable atmosphere to Mars. Which would render the planet unsafe to be on while each one of those atmosphere lumps gets delivered. Then, once we've mined out the asteroid belt, we'll probably need to be mining the Kuiper belt to supply the necessary volatiles. But that's a problem for the 4th or 5th millennium of the terraforming project.
Incidentally, your thousand-odd habitats would be a total population of around a million - maybe two million. It depends on whether or not you want each one to have a large enough stable population to justify an institution of higher education, or to work on the principal of sending the offspring away from home to college. Good for mixing the gene pools, unpopular with the parents. A problem every small settlement has faced since Ur.
and made the Earth a sustainable place to live for the very long term, we're one catastrophic event away from oblivion.
As a geologist, "very long term" means a little more to me than it does to most people. I'd just settle for doubling the lifetime of the species - which would be 250 to 350 thousand years more. On which time scale, terraforming Mars almost looms into feasibility - if you can find enough volatiles to make an atmosphere worth speaking of.
But otherwise, yes, we're one catastrophic event from oblivion. And we're in the process of lining up three or four such catastrophes for the next generation (or your generation, depending on your age) to survive.
Something like a 15 month round trip for a month (or 2 years - no other alternatives unless you have a way around orbital mechanics) of ground time. That's some vacation. Oh, and the fact that you'd only e outside a metal-walled box for a few hours of EVA during that time.
Even a tiny amount of dust that got in would soon make people sick and clog up machinary.
So, the non-trivial amounts of perchlorate dust I had floating around in my bedroom as a kid (make your own explosives - normal child's play) made me ill. Odd that, I never noticed.
You're probably not wrong about dust having the potential to clog machinery - if the normal moisture levels in an atmosphere fit for humans to breathe did't condense onto the dust and precipitate it out to the ground. So you have to dust. Big deal. It's not as if your humans wouldn't be shedding dust-size particles of skin every second of every day. Big deal- just don't have humans in your pristine, ultra-clean Mars colony. "Oh!"
you'd have to fully wash and decontaminate a spacesuit each time it came back into the facility
Do you actually need to bring the space suit in every time you use it? There are designs (designs only, at this stage) where the free-standing areonaut backs up to an airlock which clamps onto the sealing rim to their life support backpack, checks pressure integrity, gives the machinery a wash and dust-off, then un-dogs the sealing plate of the primary airlock, and disconnects the consumables part of the backpack from the rim and removes it. That exposes the areonaut to the (pressure-integrity-checked) interior of the airlock from buttocks to shoulder, and they back out of the suit, leaving the arms, legs and head of the suit outside and exposed to Mars' atmosphere. The pressure difference leaves the arms and legs sticking out like a mild case of rigor mortis. After cleaning the suit of their nappies (EN_US : "diaper", I think?) and athletes foot (would you like to use someone else's used nappy?), the areonaut exits the airlock, which then becomes the second level of pressure barrier between them and the lethal near-vacuum (0.6% off vacuum) outside and head off to the sewage plant with their waste.
Short version : you only bring the body of the suit into the habitat when you need to conduct repairs, and you wash it free of dust as part of that process.
These arn't the sort of problems you can hand wave away.
If you consider that handwavery, feel free.
Actually, the Apollo selenonauts met the problem of dust, and worried about it - but it didn't actually cause any significant problems. However NASA, Rockocmoc, ESA and CNSA have been giving it a lot of thought since then. Handwavium aside, the problem is one you can engineer around.
Shock horror, but the locker room type scenes beloved of Hollywood producers are... Hollywood bullshit.
Thankfully, the Galileo saga appears to be coming to a close. On October 24th, FCC Chairman Ajit Pai announced that the Commission will vote in November (presumably in their November 15th open meeting) on allowing American devices to use signals from Galileo. Given the positive tone of the announcement, it seems that Galileo may be headed for official approval
Anyone heard any news?
Otherwise, maybe it's time for several tens of thousands of relevant people to request, fill out and return, some forms:
United States Electronic Code of Federal Regulations (eCFR) Title 47 â Chapter I â Subchapter B (pause, take a deep breath) â Part 25 â Subpart B â Section 25.131 â (j) says:
Receive-only earth stations operating with non-U.S. licensed space stations shall file an FCC Form 312 requesting a license or modification to operate such station.
After several years of work by seismic survey boats, seabed samplers, more seismic on a different spacing, and a team of a dozen geologists working for about 5 years on "developing the prospect... and several lawyers and bean counters working on the drilling permits and financials... I've seen 300+million year errors assigned to a structure. And proved wrong as soon as we put a drill bit into the structure.
When a meteor impacts, most of it's material is ejected from the initial impact crater by the pressure of thousands of cubic metres of rock vapour (no, that's not a typo for "liquid") where the landscape and the impactor boiled away on contact. (Whether the impactor was "dirty snowball" or "nickel-iron" doesn't matter ; same for the impact site).
You're not wrong about there being inhomogeneity in the minor element and isotopic composition of the upper mantle - as sampled by diamond inclusions, and including extinct isotopic clocks - and much of the original complement of siderophile ("iron-loving") elements (includes gold and some PGEs [platinum group elements]) having ended up in the core. But that is most likely the result of impacts after the Moon-forming impact - which would have probably homogenised the mantle fairly well.
The Vredefort impact structure (to which I think you refer) is a billion or two years too late to have been involved significantly in that - and the impactor got fairly evenly coated over the inner solar system. It is certainly associated with PGE and gold mining - a classic area, I've had microscope training on samples from there - but whether that is actually "extra-terrestrial" in any meaningful sense : no.
The deep fracturing caused by the Vredefort impactor seems to have allowed fluids (water, carbon dioxide) to mobilise PGEs and gold from the upper mantle below the impact, which then came up towards the surface and became involved with volcanism (and volcaniclastic sediments, in running water) near the surface tens or hundreds of millions of years after the impact.
There does seem to be a relationship between the events, but it's a lot more subtle than the "gold rich asteroid buries itself". Which is a story that appeals to TV documentary producers, if not actual geologists. (Sorry - I did my Honours in mantle petrology. Fuck all use for finding oil, but far more interesting!)
Whether those are an impact field (from a near-surface airburst), or a meteorological phenomenon remains, TTBOMK, to be determined. And part of the problem of (natural) airbursts is that they don't leave a huge amount of evidence on the ground.
That is, indeed, one of the lines of argument that others have been using to debate what the actual impact date was. The age of the rock cut by the (putative) impact is 1.7 to 1.9 Ga, providing a terminus post quem for the structure. And the event didn't happen within recorded history (say, several thousand years, the terminus ante quem). Narrowing the gap between those termini... needs more data. I'd go for sea-bed sampling using a piston corer - where the water is deep enough to have floated the last few millions of years of ice above the seabed sludge. Probably only a weeks work with an ice-breaker with over-the-side or through-the-middle craneage to handle the coring equipment. Sites - I've got a long list of about 4 areas, but that'll need refinement. What's my budget for renting such a boat?
For a 31km (nominal) diameter crater, the nature of the substrate at the impact site is pretty much irrelevant. Any substrate with a boiling point below 5000 to 10000 K would flash to vapour due to the thermal radiation from the plasma shock wave ahead of the impactor.
Carbon dating is not the only tool in the dating toolbox. For this, I'd hope for micropalaeo, but since they don't mention that they either couldn't budget for getting seabed samples (icebreakers with a hefty over-side crane, significant tonnage of equipment... not cheap), or there's too much bioturbation/ glacial gouging in the samples available (seabed evaluations for IODP drilling sites as well as Cairn's oil exploration of a few years ago would have possibly been usefully close), and micropalaeo didn't work.
It's unfortunate that they can't tightly constrain the impact date. But there is no actual guarantee that any particular site will [b]preserve[/b] useful data. Or, indeed, that researchers find it. Your time on site may be just a couple of working days book-ended by the times that helicopters or boats can get to your embarkation point.
There are a couple of perfectly serious researchers who are claiming evidence from "impact-generated" spherules to signs of radiation (what? how does that figure?) at a variety of locations in the "north east" of the American continent - and related claims that this supports models that have multiple waves of Siberians (where "palaeoindian" comes from... [SURUG]. Probably that incompetent mathematician and lucky Italian navigator, Chris Columbus) entering the Americas at different times and by different routes. It is a reasonable claim, but I don't see it having reached anywhere near "consensus." Then again, it's not a topic I follow with any effort - there are enough Americans to get overexcited about it.
the eccentricity of the orbit depends, in part, on the object's velocity.
That's.... well, a... tautology would be a polite way of putting it. Since orbits are all about the interplay of velocity with position and gravity field. Of course, the velocity varies somewhat between periapse and apoapse - if the latter has any meaning. Actually, reading up on the messages announcing the realisation of the importance of 'Oumuamua, the humans who looked at the machine-generated orbital solutions paid more attention to the V_inf (velocity at infinite range - velocity at apoapse for a hyperbolic orbit) as more indicative of an interstellar origin than the eccentricity. Several examples were discussed of records of objects of undisputed solar system origin being ejected on hyperbolic orbits (after interacting with Jupiter.
Given that TFS states (wrongly) that there were at least 100 comets in parabolic orbits
No it doesn't - and I wrote the damned summary, not just copy-pasting the article from some pre-digested pap website. I quote the paper about the assumption of parabolic orbits for hundreds of comets since the 1950s, and the context of that has the clear expectation (written by the paper's authors, not me) that at least some of these parabolic solutions would be found to be wrong, or at least, unjustifiable with today's better computational tools.
Now, of course, I know that TFS misquoted the paper,
Go to the paper - the published PDF, not just the abstract. Page 1, section 1, paragraph 1. Compare the paper with my alleged misquote. How have I misrepresented the authors?
I still think that developing an idea for a technology that would get a probe large enough to carry a vonNeumann machine and a fistful of gametes & bacteria at more that 0.1c is a more immediate concern. After all, if you've got a 0.2c propulsion technology, you can launch several robotic prototypes ahead of the actual probe with the expensive equipment (or even people) aboard.
Slashdot Mirror
The UK has nuclear weapons. Some of them are probably in United States (or Canada) territorial waters, with sufficient range to hit many (most) million plus cities in the contiguous US. Is that sufficient reason. (I assume that the Trumpian concept that "international law has no meaning" has already been hung from a tree in the finest lynching style. TrÃs American!)
About the same as 4 billion years ago, and 5 billion years ago - every year around 3 solar masses of interstellar medium were turned into stars, most of which were red dwarfs (and still are) though a couple of times a decade a star with a sun-like mass gets made. More rarely, larger stars would get formed.
TFA has no implication that anything particularly unusual was happening then. At this moment, the portion of the Milky Way visible to us (maybe one tenth of it), has several hundred open clusters of the form which they are suggesting the Sun and HD186302 once shared.
These are
??
There is a problem of coverage here. Out of the relatively small areas of the sky surveyed, to a quite shallow depth of survey, with major biases towards non-Sun-like stellar systems in the search methods, we have not found an Earth-a-like.
But we have found a number of somewhat similar systems.
And there are literally billions of un-surveyed systems in the galaxy.
While we haven't found an Earth-alike system, it's fairly safe to conclude that they are out there. It's as unsure as the prevalence of unfocussed video cameras and gorilla suits in Oregon being a good predictor of at least one Bigfoot hoaxer in America.
I make that about 7000 miles/ year on average dispersion velocity. I've had cars that travel faster than that. Actually, I don't think I've had a car which didn't travel faster than that, on average, over a year.
Taking you seriously, humans - and all other mammals - are fish. In the sense that we are craniate vertebrates and not sharks. Not all fish live in the sea. Some fish fly better than humans.
For those who don't know, the family of plants that includes the grasses - including all of our major calorie crops - evolved in the Eocene, some 15 to 20 million years after the end of the Cretaceous.
It would have effects, agreed. But having worked from the Bristol Channel (second highest tidal range in the world, after Bay of Fundy) to the Mediterranean (negligible tidal range), I'm really unclear as to which is "better", and which is "messed with"? Could you elaborate on why one is better than the other - or do you just mean "different to what I'm used to EQUALS worse"?
Firstly, you'd have to concentrate the damage into one relatively small area, which is going to make a deep hole.
Secondly, the Moon's rotational locking to it's orbit around the Earth is considerably helped by the centre-of-mass of the Moon being displaced by some 60km from it's centre-of-figure towards the Earth. That's a characteristic that seems to have been inherited from the "magma ocean phase of the formation of the Moon - the first few thousand years (maybe approaching a million?) after the Moon formed.
Care to show some working to go with that? I'm getting more like a million. Oh, sorry, that's for Mars - so on the order of 30,000 comets for the Moon. Not that it would hold onto the vapour for more than a few days.
We'll need to develop the habitats anyway, as work camps for collecting the volatile-rich asteroids to deliver a workable atmosphere to Mars. Which would render the planet unsafe to be on while each one of those atmosphere lumps gets delivered. Then, once we've mined out the asteroid belt, we'll probably need to be mining the Kuiper belt to supply the necessary volatiles. But that's a problem for the 4th or 5th millennium of the terraforming project.
Incidentally, your thousand-odd habitats would be a total population of around a million - maybe two million. It depends on whether or not you want each one to have a large enough stable population to justify an institution of higher education, or to work on the principal of sending the offspring away from home to college. Good for mixing the gene pools, unpopular with the parents. A problem every small settlement has faced since Ur.
As a geologist, "very long term" means a little more to me than it does to most people. I'd just settle for doubling the lifetime of the species - which would be 250 to 350 thousand years more. On which time scale, terraforming Mars almost looms into feasibility - if you can find enough volatiles to make an atmosphere worth speaking of.
But otherwise, yes, we're one catastrophic event from oblivion. And we're in the process of lining up three or four such catastrophes for the next generation (or your generation, depending on your age) to survive.
Big tourist market, that!
So, the non-trivial amounts of perchlorate dust I had floating around in my bedroom as a kid (make your own explosives - normal child's play) made me ill. Odd that, I never noticed. You're probably not wrong about dust having the potential to clog machinery - if the normal moisture levels in an atmosphere fit for humans to breathe did't condense onto the dust and precipitate it out to the ground. So you have to dust. Big deal. It's not as if your humans wouldn't be shedding dust-size particles of skin every second of every day. Big deal- just don't have humans in your pristine, ultra-clean Mars colony. "Oh!"
Do you actually need to bring the space suit in every time you use it? There are designs (designs only, at this stage) where the free-standing areonaut backs up to an airlock which clamps onto the sealing rim to their life support backpack, checks pressure integrity, gives the machinery a wash and dust-off, then un-dogs the sealing plate of the primary airlock, and disconnects the consumables part of the backpack from the rim and removes it. That exposes the areonaut to the (pressure-integrity-checked) interior of the airlock from buttocks to shoulder, and they back out of the suit, leaving the arms, legs and head of the suit outside and exposed to Mars' atmosphere. The pressure difference leaves the arms and legs sticking out like a mild case of rigor mortis. After cleaning the suit of their nappies (EN_US : "diaper", I think?) and athletes foot (would you like to use someone else's used nappy?), the areonaut exits the airlock, which then becomes the second level of pressure barrier between them and the lethal near-vacuum (0.6% off vacuum) outside and head off to the sewage plant with their waste.
Short version : you only bring the body of the suit into the habitat when you need to conduct repairs, and you wash it free of dust as part of that process.
If you consider that handwavery, feel free.
Actually, the Apollo selenonauts met the problem of dust, and worried about it - but it didn't actually cause any significant problems. However NASA, Rockocmoc, ESA and CNSA have been giving it a lot of thought since then. Handwavium aside, the problem is one you can engineer around.
Shock horror, but the locker room type scenes beloved of Hollywood producers are ... Hollywood bullshit.
Anyone heard any news? Otherwise, maybe it's time for several tens of thousands of relevant people to request, fill out and return, some forms :
After several years of work by seismic survey boats, seabed samplers, more seismic on a different spacing, and a team of a dozen geologists working for about 5 years on "developing the prospect ... and several lawyers and bean counters working on the drilling permits and financials ... I've seen 300+million year errors assigned to a structure. And proved wrong as soon as we put a drill bit into the structure.
You're not wrong about there being inhomogeneity in the minor element and isotopic composition of the upper mantle - as sampled by diamond inclusions, and including extinct isotopic clocks - and much of the original complement of siderophile ("iron-loving") elements (includes gold and some PGEs [platinum group elements]) having ended up in the core. But that is most likely the result of impacts after the Moon-forming impact - which would have probably homogenised the mantle fairly well.
The Vredefort impact structure (to which I think you refer) is a billion or two years too late to have been involved significantly in that - and the impactor got fairly evenly coated over the inner solar system. It is certainly associated with PGE and gold mining - a classic area, I've had microscope training on samples from there - but whether that is actually "extra-terrestrial" in any meaningful sense : no.
The deep fracturing caused by the Vredefort impactor seems to have allowed fluids (water, carbon dioxide) to mobilise PGEs and gold from the upper mantle below the impact, which then came up towards the surface and became involved with volcanism (and volcaniclastic sediments, in running water) near the surface tens or hundreds of millions of years after the impact.
There does seem to be a relationship between the events, but it's a lot more subtle than the "gold rich asteroid buries itself". Which is a story that appeals to TV documentary producers, if not actual geologists. (Sorry - I did my Honours in mantle petrology. Fuck all use for finding oil, but far more interesting!)
Whether those are an impact field (from a near-surface airburst), or a meteorological phenomenon remains, TTBOMK, to be determined. And part of the problem of (natural) airbursts is that they don't leave a huge amount of evidence on the ground.
Actually, it's more likely to be in the mud of the seabed. But still under hundreds or thousands of metres of water, some of it solid.
Stretch, is that you?
That is, indeed, one of the lines of argument that others have been using to debate what the actual impact date was. The age of the rock cut by the (putative) impact is 1.7 to 1.9 Ga, providing a terminus post quem for the structure. And the event didn't happen within recorded history (say, several thousand years, the terminus ante quem). Narrowing the gap between those termini ... needs more data. I'd go for sea-bed sampling using a piston corer - where the water is deep enough to have floated the last few millions of years of ice above the seabed sludge. Probably only a weeks work with an ice-breaker with over-the-side or through-the-middle craneage to handle the coring equipment. Sites - I've got a long list of about 4 areas, but that'll need refinement. What's my budget for renting such a boat?
Carbon dating is not the only tool in the dating toolbox. For this, I'd hope for micropalaeo, but since they don't mention that they either couldn't budget for getting seabed samples (icebreakers with a hefty over-side crane, significant tonnage of equipment ... not cheap), or there's too much bioturbation/ glacial gouging in the samples available (seabed evaluations for IODP drilling sites as well as Cairn's oil exploration of a few years ago would have possibly been usefully close), and micropalaeo didn't work.
It's unfortunate that they can't tightly constrain the impact date. But there is no actual guarantee that any particular site will [b]preserve[/b] useful data. Or, indeed, that researchers find it. Your time on site may be just a couple of working days book-ended by the times that helicopters or boats can get to your embarkation point.
There are a couple of perfectly serious researchers who are claiming evidence from "impact-generated" spherules to signs of radiation (what? how does that figure?) at a variety of locations in the "north east" of the American continent - and related claims that this supports models that have multiple waves of Siberians (where "palaeoindian" comes from ... [SURUG]. Probably that incompetent mathematician and lucky Italian navigator, Chris Columbus) entering the Americas at different times and by different routes. It is a reasonable claim, but I don't see it having reached anywhere near "consensus." Then again, it's not a topic I follow with any effort - there are enough Americans to get overexcited about it.
Have you ever worked in the discovery phase of an observational science? Obviously not.
That's .... well, a ... tautology would be a polite way of putting it. Since orbits are all about the interplay of velocity with position and gravity field. Of course, the velocity varies somewhat between periapse and apoapse - if the latter has any meaning. Actually, reading up on the messages announcing the realisation of the importance of 'Oumuamua, the humans who looked at the machine-generated orbital solutions paid more attention to the V_inf (velocity at infinite range - velocity at apoapse for a hyperbolic orbit) as more indicative of an interstellar origin than the eccentricity. Several examples were discussed of records of objects of undisputed solar system origin being ejected on hyperbolic orbits (after interacting with Jupiter.
No it doesn't - and I wrote the damned summary, not just copy-pasting the article from some pre-digested pap website. I quote the paper about the assumption of parabolic orbits for hundreds of comets since the 1950s, and the context of that has the clear expectation (written by the paper's authors, not me) that at least some of these parabolic solutions would be found to be wrong, or at least, unjustifiable with today's better computational tools.
Go to the paper - the published PDF, not just the abstract. Page 1, section 1, paragraph 1. Compare the paper with my alleged misquote. How have I misrepresented the authors?
I still think that developing an idea for a technology that would get a probe large enough to carry a vonNeumann machine and a fistful of gametes & bacteria at more that 0.1c is a more immediate concern. After all, if you've got a 0.2c propulsion technology, you can launch several robotic prototypes ahead of the actual probe with the expensive equipment (or even people) aboard.