It's not escaping from the comet that's the difficult part. It's the slowing down enough to enter Earth's orbit. First, Philae is already travelling well beyond Earth's escape velocity, so you've got to slow down a lot before you get anywhere near to an orbit; and Philae and the comet are only going to get faster as the days and weeks to perihelion tick by. Even at Aphelion the comet is travelling at half of Earth's escape velocity. Second, Philae has no heat shield, so you're not going to be able to knock off any serious amount of speed through aerobraking. Third, Philae has only one thruster, which can be fired once only and only at full strength (and that thruster has already failed). Fourth, even if you could somehow remotely fix the thruster, Philae can only orient itself in one plane. So, you only have one chance at a course correction. Fifth, 67P (and Philae with it) doesn't get close enough to the Earth to do any appreciable gravity assist manoevres (the closest it gets is halfway between Mars and Earth). Finally, and most importantly, Philae has no way of launching itself, so its going to have to rely on a violent outgassing, which only happens near perihelion.
So, Philae would have to be blasted off of 67P by a random yet serendipitous outgassing that throws it clear of the comet, without destroying it, at an attitude that the single reaction wheel can compensate for, on the off chance that the previously malfunctioning thruster can somehow push it on a perfect course of multiple Jupiter/Mars flybys that would cut the lander's speed in half, allowing it to settle into an orbit around Earth. The odds against it are, if you'll pardon the pun, astronomical.
The only way Philae will see Earth again, barring some future trophy hunting space jockey, is as a harbinger of 67P's crash into the planet.
Philae has the same orbital parameters as the comet. it would take quite a lot of delta-v to convert that orbit to orbitting the Earth. After all, it took ten years and four planetary slingshots in order to get it there in the first place.
What do you think we're searching the asteroids for? The only thing of value in space: water. Water outside of a gravity well is propellant. Just run it past a hot nuclear pile, and it turns to steam. Voila... cheap delta-V
I'll admit I'm a few seasons behind, but garbage or not I'd have to say it's still one of the better shows out there. And yes, that probably says a hell of a lot more about the vast sewage pit of modern programming than it does about the quality of Doctor Who.
Exactly. Doctor Who is the "reference plane" against which all other television programming is measured.
First, You're looking at monthly stats for currently active missions. Second, Over the past several years, Canada's peacekeeping has largely been done through UN sanctioned NATO missions rather than directly through the UN itself. Third, sadly, since the mid 1990s. Canada has been reducing its peacekeeping role - which explains why Canada's numbers are so low.
War doesn't decide who is right. It only decides who is left.
In Canada, Remembrance Day is a solemn day, full of reflection and recognition of the price Canada has paid for peace. It's definitely not a pompous flag waving day because Canada doesn't go to war to crush her enemies. Canada doesn't start wars. It ends them. We have committed more troops to UN peacekeeping efforts than any other country. As such, I think when Canadians do consider the deaths of enemy soldiers it is with sympathy rather than with Schadenfreude.
Thanks! I was beginning to think I was the only person who didn't know. I've seen the acronym before as Pre-Authorized Contribution, but I couldn't make any contextual leap to what a SuperPAC might be.
The Christian belief is that without a knowledge of God, a person is judged based on their own conscience, not that they would go to Heaven by default. However, that is beside the point. Christians are commanded to go and make disciples of all nations.
Any efficiency is too efficient. Expect these idealist clowns to be sued into oblivion by the petroleum industry.
Why? You still need the jet fuel. The Petroleum Industry still gets their cut. They may actually sell more jet fuel if this works out. Imagine every battery replaced by a canister of jet fuel. It would be the Petroleum Industry's dream.
GPS is nice but people often misunderstand its accuracy, availability & stability. First off accuracy, your average private GPS (TomTom, Phone, handheld) is only about 30' accurate on a fairly good day, so if you buried a valuable out in the middle of a field and your only reference to it was your phones GPS you might have to dig for quite a while in an area the size of a double garage in order to find it.
The GPS satellite system only tells you your latitude, longitude, and altitude (and the time). Anything else is the fault of the navigation computer. Map updates, or lack thereof, are Garmin's fault. Not Clinton's.
it goes to voicemail? You realize that voicemail on cellphones isn't built into the bloody phone right? It's from your provider.
Just the same as my voice calls can be tapped so can my voice mail, but a reasonable level of privacy is there unless I'm investigated.
And no I don't. This may be a hard concept for you as you're probably a bit younger than I am, but people do not need to be able to talk to me at all times of the day no matter where I am. 99.99% of the time it is never an emergency that I really wished I got that phone call.
You know, once upon a time, people didn't have cell phones, just regular ones. When you called, they were simply 'not home' and you had to wait until they called you back, or you had to just try again another time when you think they might be home.
I lived in that once upon a time, before cell phones and answering machines... well, before the cassette tape answering machines anyway. So I do realize that voicemail isn't built into the cell phone. That's why I said third party. So what kind of phone do you have that has two weeks of standby time?
Do you post your call answering schedule somewhere? What happens when someone wants to get in touch with you during your non-answering hours? Third party voicemail? So much for privacy. So much for cheap.
My previous comment was based on the summary. Having Read The Fancy Article, the research is being done in the state of Maryland, so the FAA would be in authority. The reason for the hectares is that geologic surveys are now done in metric.
Actually, there is an integer multiple... or rather, an integer ratio. Since we are talking about land, we have to use US Survey measurements. A Survey Foot is, by definition, 1200/3937 metres. So an acre, being 43560 square feet, would be 43560*(1200/3937)^2 or 62726400000/15499969 square metres. There are 10000 square metres in a hectare, so an acre is 6272640/15499969 hectares exactly*.
*At least, in some states. Not all states use survey feet. Some use customary feet, which changes the numbers slightly. However, since both customary feet and survey feet are, by definition, exact fractions of the metre, the argument still holds. Only the numbers would change. Of course, the underlying data (The US National Spatial Reference System NAD 83(2011/MA11/PA11) epoch 2010.00) is metric from the outset and is converted to feet for publication.
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There is a third option: The boy is a "paper" MCP. He knows the right answer to the questions, but doesn't understand the reasoning behind it.
Money is pretty useless. You can't eat it or shelter yourself from rain with it.
Canada's new polymer bills would make for a fairly waterproof shelter, if you layered them properly.
It's not escaping from the comet that's the difficult part. It's the slowing down enough to enter Earth's orbit. First, Philae is already travelling well beyond Earth's escape velocity, so you've got to slow down a lot before you get anywhere near to an orbit; and Philae and the comet are only going to get faster as the days and weeks to perihelion tick by. Even at Aphelion the comet is travelling at half of Earth's escape velocity. Second, Philae has no heat shield, so you're not going to be able to knock off any serious amount of speed through aerobraking. Third, Philae has only one thruster, which can be fired once only and only at full strength (and that thruster has already failed). Fourth, even if you could somehow remotely fix the thruster, Philae can only orient itself in one plane. So, you only have one chance at a course correction. Fifth, 67P (and Philae with it) doesn't get close enough to the Earth to do any appreciable gravity assist manoevres (the closest it gets is halfway between Mars and Earth). Finally, and most importantly, Philae has no way of launching itself, so its going to have to rely on a violent outgassing, which only happens near perihelion.
So, Philae would have to be blasted off of 67P by a random yet serendipitous outgassing that throws it clear of the comet, without destroying it, at an attitude that the single reaction wheel can compensate for, on the off chance that the previously malfunctioning thruster can somehow push it on a perfect course of multiple Jupiter/Mars flybys that would cut the lander's speed in half, allowing it to settle into an orbit around Earth. The odds against it are, if you'll pardon the pun, astronomical.
The only way Philae will see Earth again, barring some future trophy hunting space jockey, is as a harbinger of 67P's crash into the planet.
The amount of solar energy passing the Earth, closer than the Moon's orbit...
I'm not sure what you mean by that. Are you talking about a disk sized collector the size of the Moon's orbit?
Philae has the same orbital parameters as the comet. it would take quite a lot of delta-v to convert that orbit to orbitting the Earth. After all, it took ten years and four planetary slingshots in order to get it there in the first place.
Nakedness is an artistic symbol for innocence, and the BBC doesn't protect anyone from anything. It is a broadcasting company, nothing more.
What do you think we're searching the asteroids for? The only thing of value in space: water. Water outside of a gravity well is propellant. Just run it past a hot nuclear pile, and it turns to steam. Voila... cheap delta-V
I'll admit I'm a few seasons behind, but garbage or not I'd have to say it's still one of the better shows out there. And yes, that probably says a hell of a lot more about the vast sewage pit of modern programming than it does about the quality of Doctor Who.
Exactly. Doctor Who is the "reference plane" against which all other television programming is measured.
Whew! What a relief! I'm not a pilot, but that looks like a bad angle to be approaching a runway, especially at night.
First, You're looking at monthly stats for currently active missions. Second, Over the past several years, Canada's peacekeeping has largely been done through UN sanctioned NATO missions rather than directly through the UN itself. Third, sadly, since the mid 1990s. Canada has been reducing its peacekeeping role - which explains why Canada's numbers are so low.
Cumulatively Canada, has committed the most troops, over 125,000 altogether.
Link.
In every war, at least one side was wrong.
War doesn't decide who is right. It only decides who is left.
In Canada, Remembrance Day is a solemn day, full of reflection and recognition of the price Canada has paid for peace. It's definitely not a pompous flag waving day because Canada doesn't go to war to crush her enemies. Canada doesn't start wars. It ends them. We have committed more troops to UN peacekeeping efforts than any other country. As such, I think when Canadians do consider the deaths of enemy soldiers it is with sympathy rather than with Schadenfreude.
Thanks! I was beginning to think I was the only person who didn't know. I've seen the acronym before as Pre-Authorized Contribution, but I couldn't make any contextual leap to what a SuperPAC might be.
The Christian belief is that without a knowledge of God, a person is judged based on their own conscience, not that they would go to Heaven by default. However, that is beside the point. Christians are commanded to go and make disciples of all nations.
Any efficiency is too efficient. Expect these idealist clowns to be sued into oblivion by the petroleum industry.
Why? You still need the jet fuel. The Petroleum Industry still gets their cut. They may actually sell more jet fuel if this works out. Imagine every battery replaced by a canister of jet fuel. It would be the Petroleum Industry's dream.
GPS is nice but people often misunderstand its accuracy, availability & stability. First off accuracy, your average private GPS (TomTom, Phone, handheld) is only about 30' accurate on a fairly good day, so if you buried a valuable out in the middle of a field and your only reference to it was your phones GPS you might have to dig for quite a while in an area the size of a double garage in order to find it.
Burying things is against Geocaching rules.
But Glosnass, BeiDou, and Galileo are all Global Navigation Satellite Systems as well. Best tell your engineers to stick to calling GPS GPS.
The GPS satellite system only tells you your latitude, longitude, and altitude (and the time). Anything else is the fault of the navigation computer. Map updates, or lack thereof, are Garmin's fault. Not Clinton's.
it goes to voicemail? You realize that voicemail on cellphones isn't built into the bloody phone right? It's from your provider. Just the same as my voice calls can be tapped so can my voice mail, but a reasonable level of privacy is there unless I'm investigated.
And no I don't. This may be a hard concept for you as you're probably a bit younger than I am, but people do not need to be able to talk to me at all times of the day no matter where I am. 99.99% of the time it is never an emergency that I really wished I got that phone call.
You know, once upon a time, people didn't have cell phones, just regular ones. When you called, they were simply 'not home' and you had to wait until they called you back, or you had to just try again another time when you think they might be home.
I lived in that once upon a time, before cell phones and answering machines... well, before the cassette tape answering machines anyway. So I do realize that voicemail isn't built into the cell phone. That's why I said third party. So what kind of phone do you have that has two weeks of standby time?
That doesn't help. There was no compulsion to pay using that link either.
I only turn it on when I expect a call
Do you post your call answering schedule somewhere? What happens when someone wants to get in touch with you during your non-answering hours? Third party voicemail? So much for privacy. So much for cheap.
They're just lazy and making a life choice to be poor.
Just like their parents before them.
I ran cable for internet connections. Where's my cut of the action?
My previous comment was based on the summary. Having Read The Fancy Article, the research is being done in the state of Maryland, so the FAA would be in authority. The reason for the hectares is that geologic surveys are now done in metric.
Actually, there is an integer multiple... or rather, an integer ratio. Since we are talking about land, we have to use US Survey measurements. A Survey Foot is, by definition, 1200/3937 metres. So an acre, being 43560 square feet, would be 43560*(1200/3937)^2 or 62726400000/15499969 square metres. There are 10000 square metres in a hectare, so an acre is 6272640/15499969 hectares exactly*. *At least, in some states. Not all states use survey feet. Some use customary feet, which changes the numbers slightly. However, since both customary feet and survey feet are, by definition, exact fractions of the metre, the argument still holds. Only the numbers would change. Of course, the underlying data (The US National Spatial Reference System NAD 83(2011/MA11/PA11) epoch 2010.00) is metric from the outset and is converted to feet for publication.