> This way they can lock this modified iOS to the one device in question.
That's not what the FBI is asking for, and it's not clear that's even feasible. Public/private key authentication for software updates usually has nothing to do with identifying the individual target device, and I'd be very surprised if Apple is maintaining a set of public keys for every device they manufacture that could be used for that kind of device specific software upgrade management.
> The reason Blackberry went under has absolutely nothing to do with it opening up the platform to the government. It had everything to do with the instability of their server infrastructure.
I'll disagree: Both were signs of some fundamental failures at Blackberry, and a failure to understand the desires of the growing market for smarter, portable devices., That included more bandwidth, reliable service that could be used by even fools, and a sense of personal security for private data. The "security hardened Blackberry", for example, was a very poor marketing decision. It implied that the normal Blackberry had little security in the first place.
Which is why they trade data with the NSA, who does it for them. Look into the "Echelon" program: various nations involved in it skirt domestic laws against monitoring their citizens by exchanging data with other nations who have no qualms about monitoring other nations.
The connection between the hotspot and a cell phone network is encrypted. The connection of wifi devices to the hotspot is often left unencrypted or with a published or guessable passphrase, for convenience of the hotspot users. Cross-connect them, and you have fascinating issues.
Cross connecting to other devices on the same private subnet, behind the same NAT, is a problem. It's aggravated if devices in the same NAT have non-firewalled and non-monitorable connections to alternative networks at the same time.
> If you set up your own WiFi hotspot, say using your cellular phone, you are not putting traffic on the facility network,
As long as the traffic from the hostspot stays only on that VLAN, then yes. Part of the difficulty is that it does _not_ stay there. People cross connect networks as a matter of course, for example with laptops that have both wired and wifi connections, and they are horrible about the resulting security problems.
In essence, yes. Putting a fireall between the local clients and the rest of the Internet, or even port blocking certain classes of internal traffic, protects the clients and the rest of the Internet from quite a few vulnerabilities, such as unsecured sharing of the "C$" share with no admin password that is prevalent on poorly managed Windows laptops. And it reduces the cost of the service for the hotel by allowing bandwidth limiting on the controlled "free" access.
I run into similar issues with "free" services in coffee shops, offices, and workspaces all the time. They tend to be plague pits of problems: a few filters at the firewall improves the service _enormously_, even though it's not a robust security solution.
> The protocol design must be such that the server sends a bigger amount of data to an unverified source address than it has received in the request.
Not necessarily. The equivalent is not that of lasers, where amplification and synchronization occurs inside the device. DDOS does not require multiplication inside the attack vactor itself. It requires overwhelming volume at the target. DDOS is _cheaper_ and easier if there's an effective amplificaiton technique, but can be done quite effectively by distributing the transmission across a large enough array of attack systems. It can be done, for instance, by simply spreading a coordinated HTTP connection across many attacking systems, each of them with an appropriate bit of pre-programmed malware to attack at a specific time.
The risks and difficulty of coordinating are much less if there is no amplification at the hosts involved in transmitting the DDOS, but it's not strictly necessary for DDOS. Even the "Slashdot effect" of a company mentioned in a Slashdot article can bring down a web service.
> obviously, google is offering a public pxe boot over-the-internet service we havent been told about.
I've done it when hurried. It's sometimes easier to run an internal DHCP relay pointed to a well configured externally accessible DHCP server and TFTP server to get fast PXE setups in a remote environment. It's especially useful if you have a DMZ or NAT'ed internal network and set up the TFTP server outside the local VLAN.
I only open them to external traffic temporarily, but many home users and beginning sysadmins frankly insist on exposing their internal hosts, with public IP addresses. The practice of publicly exposed services, includiing TFTP, is so rampant on campuses and small businesses that a very real part of me hopes that IPv6 is never fully adapted, to ensure that the limited IPv4 address space _forces_ people to surrender unnecessary public IP addresses and take the elementary step of activating NAT simply to reduce the ease of abusive access to the Internet at large.
I've also caught employees taking calls from recruiters on their morning commute, to avoid using the phone in their offices where they may be overheard by colleagues. I've only had to take someone like that aside for a personal chat once, when I was involved in consulting work with their employer and they were flat-out lying to the recruiter. But there's a real risk of being overheard when you do this.
911 calls from cell phones on public transit are relatively rare. But many of us use the data links on our smart phones to check our schedules for connections for other buses or for trains. Many of us in high demand work also respond to text based alerts during lengthy commutes. We're not loud, we're not speaking on the cell phones, and it's much safer to do this on public transit than it is to drive home and have to pull off the road to handle an alert. So it sounds like he's interfering with people who are being responsible and safe, as well as those who are rude.
One also has to not try to take credit for ideas from popular television shows, such as the Six Million Dollar Man, from 1973. Or try to take credit or the hundreds if not thousands of science fiction stories with artificial limbs from before that.
This reminds me that I'm actually seeing signs of a revival of dotcom business plans. Exciting "new" ideas are being funded in startup companies, ideas that gathered funding but didn't work out profitably 15 years ago, either. Facial recognition and natural speech comprehension and social media advertising projects are all on the upswing.\
Fingerprint scanners have long been proven vulnerable to the most elementary of attacks. There is a stack of references to gelatin based fingerprint replication, including http://www.theregister.co.uk/2... And MythBusters did a very useful comparison of the most robust and expensive fingerprint scanners at https://www.youtube.com/watch?... .
> Ideally the justice department is not political in operation
Law enforcement is by its very nature political. It's enforcing the will of those who make the laws on the population. The ideas that it law enforcement is supposed to be dispassionate, or even-handed, or to ignore the wealth and political status of the accused are themselves political in nature.
Unfortunately for this claim, there's a fascinating "clumping" effect as larger gas clouds collect, forming supernova capable stars within the cloud, and then causing a cascade of stellar formation when the first supernovae explode. The result is that local concentrqtions are disrupted into new, more stqable, more evenly populated states. The supernovae act much like "backfires" in stellar formation by triggering early formaton, which partially exhausts the resources of the cloud.
The result is a surprising normalization of stellar clusters and of the availability of heavier isotopes in these clusters. The phenomenon is described at http://www.nasa.gov/mission_pa....
It's shoved up an artery into the brain, and is not in direct contact with neural tissue. It's inside the blood vessel, _adjacent_ to neural tissue. I'm fascinated by the stunning risks of infection if the leads to the device are left entering a blood vessel to the brain, and the well known and well understood bandwidth limitations of implanted medical electronics if it's not.
There are many regulations about free speech, but particular political views can be a condition of employment in private enterprises in most states. See breakdowns of worker political rights such as http://www.workplacefairness.o..., and review the history of corporations breaking up union activities by both subtle pressure and physical violence throughout American history.
Even if political support is "voluntary", the absence of a vocal support of leadership's views on politics, race, religion, gender, age, or sexuality have often been subtle workplace hindrances or benefits to salary and promotions.
> Depends on what you get out of it. I don't think we'll ever have a profitable space industry outside Earth orbit,
Even Earth orbit stations need water and solid raw material. SpaceX is breaking the $1000/pound price barrier. But if the price for asteroid or planetary ring water farming gets low enough, particularly using cheap solar sails to navigate them, the difficulty might well be justified by the savings. I look forward to finding out over the next few decades.
> What's the relevance of that whole, long bit of obviousness to whether we, in the near future, can not just live on -- for example -- Europa with a shit load of gargantuanly expensive support from Earth, but independently sustain ourselves on Europa?
Where, in this thread, did that ever come up? I became concerned about your statement quoted below.
> Which planets? Only the Earth has anything remotely like the environment and resources that we need to sustain life.
You're adding a new goal, namely to Independently sustain human life on another planet. That is a quite distinct topic than whether life can exist there, which you raised, and whether it's worth going there, which is what justifies NASA budgets and space exploration as a whole. I'm afraid that requirement may have that seemed quite obvious to you but wasn't in the actual questions or any published spec. Colonization of _any_ remote region takes lengthy support from the colonizing nation. There are often tools, technologies, and critical trade goods not immediately available in the colonies until they can build up the resources to produce them locally. And ecological disasters are common in distant colonies, even those with the advantage of a compatible biology such as European colonies in Australia and the Americas. One should expect disasters: I don''t believe anyone has said it would be risk free or easy. But that kind of colonization is a different question than whether it's worth establishing a base there.
I'm also afraid that this is extremely common in technological consulting or partnership. A project is proposed and bids accepted, or refused, on the basis of goals that are not made apparent in the published proposal. These goals may have seemed intrinsically obvious to the person who originally suggested the project, but need not be apparent to people paying for, or bidding on, the project. In other cases, the earlier, published goals are rejected by latecomers on the basis of _their_ assumed goals, which they've often failed to explicitly state and which no one involved in specifying or doing the work was part of the project. And the project can be poisoned by concerns or objections about these other goals, which were _never agreed on as part of the original project_. I'm concerned that this is what you're doing.
In real work, that's the point that it's vital to keep the original specifications in hand, and get changes written _explicitly_ so they can be billed for, and so that the project goalposts and expectations don't get moved beyond what anyone can or should provide. Very, very occasionally a new goal is added that actually makes the whole project much easier and saves everyone time and money. But I don't see that here.
There is a tremendous difference between "habitable by human life across an entire surface", which is what you seem to be describing, and "the environment and resources that we need to sustain life". I did mention the possibility of native life, given the existence of the tube worms that live near Earth's underseas volcanos, harvesting energy and chemicals from the volcanic vents, it seems quite possible that there may be life on extreme worlds that have energy and chemistry enough to provide liquid water.
Iron? That's a key for hemoglobin for many oxygen based life forms, but you and I would have a difficult time extracting it from water, rock, or even iron ore. We consume other life forms that have already concentrated energy and minerals and vitamins for us. Oxygen? Abundant oxygen on Earth apparently started when photosynthesis in plants started generating it, life from before that change was _poisoned_ by high oxygen levels. Sodium and calcium? Those are ions concentrated in Earth's oceans by the distillation of rain on land, bringing those salts to the ocean, then evaporating. It would be fascinating to examine their concentrations of those in other world's exposed or internal oceans and learn what other processes affect water chemistry there. How much do you need for life, if any?
The point is that nature does not "prepare the ideal chemical environment" and life appears automatically to take advantage of it. It seems that life starts from quite limited forms and capabilities, capabilities quite limited by local resources, and takes advantage of what it finds, to its own benefit. Over time it can profoundly alter the environment. Then other life forms can develop over time to take advantage of _that_ environment, and eventually you can get quite an active and sophisticated ecosystem built on many layers of consumption and modification of the local environment. It would be fascinating, and I think very educational, to see what other approaches might have already worked.
There are genuine and quite expensive difficulties, certainly. Please note that this is a quite different claim than "Only the Earth has anything remotely like the environment and resources that we need to sustain life."
The difference has reminded me of the very, very old joke described at http://quoteinvestigator.com/2.... The situation is somewhat reversed: instead of establishing that we'd "sleep with another world" if paid millions of dollars, and now haggling over whether we'd do it for $5, you're saying that "it would cost too much to sleep on another world". But how low would the price have to be to allocate the budget to pursue this?
For example, there are potentially very profitable reasons to establish bases near Saturn. If and as space industry grows, water is an expensive commodity to ship to orbit: Most hydrogen and oxygen in modern spacecraft are used as rocket propellant, unrecoverable for use in space industry.Hydrogen is relatively easy to gather from solar wind, but oxygen becomes a commodity for both life support and energy supplies. The icy rings of Saturn are a _tremendous_ source of solar sail portable water. It takes long-term investment to harvest them, and careful management to deliver them safely and usefully to Earth orbit space industries. But in the long terms of space exploration, it could indeed be profitable to have stable, regularly harvested water deliveries from the moons of Saturn. And a stable base on a moon like Enceladus could provide tremendous scientific research benefit on possible water based life there, and also serve as a stable navigation, communications, and repair center. And with a whole local moon for material resources, one much less susceptible to orbital perturbations than a ship or space station, it could be an invaluable location for stored or emergency resources.
I'm not suggesting this is the best option or best project to pursue. But it's precisely the kind of speculative engineering and multi-purpose mission planning that NASA should be considering for longer term projects.
> Which planets? Only the Earth has anything remotely like the environment and resources that we need to sustain life.
Human life? Yes, without extensive terraforming and environmental support. But life at all? Several moons, such as Europa and Enceladus, have enough liquid water and energy to possibly support native life forms.
Slashdot Mirror
> This way they can lock this modified iOS to the one device in question.
That's not what the FBI is asking for, and it's not clear that's even feasible. Public/private key authentication for software updates usually has nothing to do with identifying the individual target device, and I'd be very surprised if Apple is maintaining a set of public keys for every device they manufacture that could be used for that kind of device specific software upgrade management.
> The reason Blackberry went under has absolutely nothing to do with it opening up the platform to the government. It had everything to do with the instability of their server infrastructure.
I'll disagree: Both were signs of some fundamental failures at Blackberry, and a failure to understand the desires of the growing market for smarter, portable devices., That included more bandwidth, reliable service that could be used by even fools, and a sense of personal security for private data. The "security hardened Blackberry", for example, was a very poor marketing decision. It implied that the normal Blackberry had little security in the first place.
Which is why they trade data with the NSA, who does it for them. Look into the "Echelon" program: various nations involved in it skirt domestic laws against monitoring their citizens by exchanging data with other nations who have no qualms about monitoring other nations.
> Personal hotspots are always encrypted.
The connection between the hotspot and a cell phone network is encrypted. The connection of wifi devices to the hotspot is often left unencrypted or with a published or guessable passphrase, for convenience of the hotspot users. Cross-connect them, and you have fascinating issues.
Cross connecting to other devices on the same private subnet, behind the same NAT, is a problem. It's aggravated if devices in the same NAT have non-firewalled and non-monitorable connections to alternative networks at the same time.
> If you set up your own WiFi hotspot, say using your cellular phone, you are not putting traffic on the facility network,
As long as the traffic from the hostspot stays only on that VLAN, then yes. Part of the difficulty is that it does _not_ stay there. People cross connect networks as a matter of course, for example with laptops that have both wired and wifi connections, and they are horrible about the resulting security problems.
Can anyone here identify the spamming company? It's difficult to judge the validity of the recruiter's apology of we don't know who it was.
In essence, yes. Putting a fireall between the local clients and the rest of the Internet, or even port blocking certain classes of internal traffic, protects the clients and the rest of the Internet from quite a few vulnerabilities, such as unsecured sharing of the "C$" share with no admin password that is prevalent on poorly managed Windows laptops. And it reduces the cost of the service for the hotel by allowing bandwidth limiting on the controlled "free" access.
I run into similar issues with "free" services in coffee shops, offices, and workspaces all the time. They tend to be plague pits of problems: a few filters at the firewall improves the service _enormously_, even though it's not a robust security solution.
And oh, yes: many firewalls, routers, and publicly exposed servers are configured by people who do not even realize they've exposed a TFTP service.
> The protocol design must be such that the server sends a bigger amount of data to an unverified source address than it has received in the request.
Not necessarily. The equivalent is not that of lasers, where amplification and synchronization occurs inside the device. DDOS does not require multiplication inside the attack vactor itself. It requires overwhelming volume at the target. DDOS is _cheaper_ and easier if there's an effective amplificaiton technique, but can be done quite effectively by distributing the transmission across a large enough array of attack systems. It can be done, for instance, by simply spreading a coordinated HTTP connection across many attacking systems, each of them with an appropriate bit of pre-programmed malware to attack at a specific time.
The risks and difficulty of coordinating are much less if there is no amplification at the hosts involved in transmitting the DDOS, but it's not strictly necessary for DDOS. Even the "Slashdot effect" of a company mentioned in a Slashdot article can bring down a web service.
> obviously, google is offering a public pxe boot over-the-internet service we havent been told about.
I've done it when hurried. It's sometimes easier to run an internal DHCP relay pointed to a well configured externally accessible DHCP server and TFTP server to get fast PXE setups in a remote environment. It's especially useful if you have a DMZ or NAT'ed internal network and set up the TFTP server outside the local VLAN.
I only open them to external traffic temporarily, but many home users and beginning sysadmins frankly insist on exposing their internal hosts, with public IP addresses. The practice of publicly exposed services, includiing TFTP, is so rampant on campuses and small businesses that a very real part of me hopes that IPv6 is never fully adapted, to ensure that the limited IPv4 address space _forces_ people to surrender unnecessary public IP addresses and take the elementary step of activating NAT simply to reduce the ease of abusive access to the Internet at large.
I've also caught employees taking calls from recruiters on their morning commute, to avoid using the phone in their offices where they may be overheard by colleagues. I've only had to take someone like that aside for a personal chat once, when I was involved in consulting work with their employer and they were flat-out lying to the recruiter. But there's a real risk of being overheard when you do this.
911 calls from cell phones on public transit are relatively rare. But many of us use the data links on our smart phones to check our schedules for connections for other buses or for trains. Many of us in high demand work also respond to text based alerts during lengthy commutes. We're not loud, we're not speaking on the cell phones, and it's much safer to do this on public transit than it is to drive home and have to pull off the road to handle an alert. So it sounds like he's interfering with people who are being responsible and safe, as well as those who are rude.
One also has to not try to take credit for ideas from popular television shows, such as the Six Million Dollar Man, from 1973. Or try to take credit or the hundreds if not thousands of science fiction stories with artificial limbs from before that.
This reminds me that I'm actually seeing signs of a revival of dotcom business plans. Exciting "new" ideas are being funded in startup companies, ideas that gathered funding but didn't work out profitably 15 years ago, either. Facial recognition and natural speech comprehension and social media advertising projects are all on the upswing.\
Fingerprint scanners have long been proven vulnerable to the most elementary of attacks. There is a stack of references to gelatin based fingerprint replication, including http://www.theregister.co.uk/2... And MythBusters did a very useful comparison of the most robust and expensive fingerprint scanners at https://www.youtube.com/watch?... .
> But, if indicted and even convicted, could they be elected anyways? This is an interesting potential constitutional issue.
Of course she could. Look into the political career of many politicians who have been convicted, such as Marion Barry.
> Ideally the justice department is not political in operation
Law enforcement is by its very nature political. It's enforcing the will of those who make the laws on the population. The ideas that it law enforcement is supposed to be dispassionate, or even-handed, or to ignore the wealth and political status of the accused are themselves political in nature.
> And our instructions were to NEVER talk about ANYTHING work related to ANYONE who did not have a need to know AND a clearance.
If you're the Secretary of State, choosing what secret information to reveal, and when, is part of the job.
Unfortunately for this claim, there's a fascinating "clumping" effect as larger gas clouds collect, forming supernova capable stars within the cloud, and then causing a cascade of stellar formation when the first supernovae explode. The result is that local concentrqtions are disrupted into new, more stqable, more evenly populated states. The supernovae act much like "backfires" in stellar formation by triggering early formaton, which partially exhausts the resources of the cloud.
The result is a surprising normalization of stellar clusters and of the availability of heavier isotopes in these clusters. The phenomenon is described at http://www.nasa.gov/mission_pa....
It's shoved up an artery into the brain, and is not in direct contact with neural tissue. It's inside the blood vessel, _adjacent_ to neural tissue. I'm fascinated by the stunning risks of infection if the leads to the device are left entering a blood vessel to the brain, and the well known and well understood bandwidth limitations of implanted medical electronics if it's not.
In a practical sense, no.
There are many regulations about free speech, but particular political views can be a condition of employment in private enterprises in most states. See breakdowns of worker political rights such as http://www.workplacefairness.o..., and review the history of corporations breaking up union activities by both subtle pressure and physical violence throughout American history.
Even if political support is "voluntary", the absence of a vocal support of leadership's views on politics, race, religion, gender, age, or sexuality have often been subtle workplace hindrances or benefits to salary and promotions.
> Depends on what you get out of it. I don't think we'll ever have a profitable space industry outside Earth orbit,
Even Earth orbit stations need water and solid raw material. SpaceX is breaking the $1000/pound price barrier. But if the price for asteroid or planetary ring water farming gets low enough, particularly using cheap solar sails to navigate them, the difficulty might well be justified by the savings. I look forward to finding out over the next few decades.
> What's the relevance of that whole, long bit of obviousness to whether we, in the near future, can not just live on -- for example -- Europa with a shit load of gargantuanly expensive support from Earth, but independently sustain ourselves on Europa?
Where, in this thread, did that ever come up? I became concerned about your statement quoted below.
> Which planets? Only the Earth has anything remotely like the environment and resources that we need to sustain life.
You're adding a new goal, namely to Independently sustain human life on another planet. That is a quite distinct topic than whether life can exist there, which you raised, and whether it's worth going there, which is what justifies NASA budgets and space exploration as a whole. I'm afraid that requirement may have that seemed quite obvious to you but wasn't in the actual questions or any published spec. Colonization of _any_ remote region takes lengthy support from the colonizing nation. There are often tools, technologies, and critical trade goods not immediately available in the colonies until they can build up the resources to produce them locally. And ecological disasters are common in distant colonies, even those with the advantage of a compatible biology such as European colonies in Australia and the Americas. One should expect disasters: I don''t believe anyone has said it would be risk free or easy. But that kind of colonization is a different question than whether it's worth establishing a base there.
I'm also afraid that this is extremely common in technological consulting or partnership. A project is proposed and bids accepted, or refused, on the basis of goals that are not made apparent in the published proposal. These goals may have seemed intrinsically obvious to the person who originally suggested the project, but need not be apparent to people paying for, or bidding on, the project. In other cases, the earlier, published goals are rejected by latecomers on the basis of _their_ assumed goals, which they've often failed to explicitly state and which no one involved in specifying or doing the work was part of the project. And the project can be poisoned by concerns or objections about these other goals, which were _never agreed on as part of the original project_. I'm concerned that this is what you're doing.
In real work, that's the point that it's vital to keep the original specifications in hand, and get changes written _explicitly_ so they can be billed for, and so that the project goalposts and expectations don't get moved beyond what anyone can or should provide. Very, very occasionally a new goal is added that actually makes the whole project much easier and saves everyone time and money. But I don't see that here.
There is a tremendous difference between "habitable by human life across an entire surface", which is what you seem to be describing, and "the environment and resources that we need to sustain life". I did mention the possibility of native life, given the existence of the tube worms that live near Earth's underseas volcanos, harvesting energy and chemicals from the volcanic vents, it seems quite possible that there may be life on extreme worlds that have energy and chemistry enough to provide liquid water.
Iron? That's a key for hemoglobin for many oxygen based life forms, but you and I would have a difficult time extracting it from water, rock, or even iron ore. We consume other life forms that have already concentrated energy and minerals and vitamins for us. Oxygen? Abundant oxygen on Earth apparently started when photosynthesis in plants started generating it, life from before that change was _poisoned_ by high oxygen levels. Sodium and calcium? Those are ions concentrated in Earth's oceans by the distillation of rain on land, bringing those salts to the ocean, then evaporating. It would be fascinating to examine their concentrations of those in other world's exposed or internal oceans and learn what other processes affect water chemistry there. How much do you need for life, if any?
The point is that nature does not "prepare the ideal chemical environment" and life appears automatically to take advantage of it. It seems that life starts from quite limited forms and capabilities, capabilities quite limited by local resources, and takes advantage of what it finds, to its own benefit. Over time it can profoundly alter the environment. Then other life forms can develop over time to take advantage of _that_ environment, and eventually you can get quite an active and sophisticated ecosystem built on many layers of consumption and modification of the local environment. It would be fascinating, and I think very educational, to see what other approaches might have already worked.
> Too far, and simply not worth the trouble.
There are genuine and quite expensive difficulties, certainly. Please note that this is a quite different claim than "Only the Earth has anything remotely like the environment and resources that we need to sustain life."
The difference has reminded me of the very, very old joke described at http://quoteinvestigator.com/2.... The situation is somewhat reversed: instead of establishing that we'd "sleep with another world" if paid millions of dollars, and now haggling over whether we'd do it for $5, you're saying that "it would cost too much to sleep on another world". But how low would the price have to be to allocate the budget to pursue this?
For example, there are potentially very profitable reasons to establish bases near Saturn. If and as space industry grows, water is an expensive commodity to ship to orbit: Most hydrogen and oxygen in modern spacecraft are used as rocket propellant, unrecoverable for use in space industry.Hydrogen is relatively easy to gather from solar wind, but oxygen becomes a commodity for both life support and energy supplies. The icy rings of Saturn are a _tremendous_ source of solar sail portable water. It takes long-term investment to harvest them, and careful management to deliver them safely and usefully to Earth orbit space industries. But in the long terms of space exploration, it could indeed be profitable to have stable, regularly harvested water deliveries from the moons of Saturn. And a stable base on a moon like Enceladus could provide tremendous scientific research benefit on possible water based life there, and also serve as a stable navigation, communications, and repair center. And with a whole local moon for material resources, one much less susceptible to orbital perturbations than a ship or space station, it could be an invaluable location for stored or emergency resources.
I'm not suggesting this is the best option or best project to pursue. But it's precisely the kind of speculative engineering and multi-purpose mission planning that NASA should be considering for longer term projects.
> Which planets? Only the Earth has anything remotely like the environment and resources that we need to sustain life.
Human life? Yes, without extensive terraforming and environmental support. But life at all? Several moons, such as Europa and Enceladus, have enough liquid water and energy to possibly support native life forms.