But e=mc^2 is special relativity, and you can derive it with high school math (they still teach math in high school, right?). Historically, it broke down the wall of separation between matter and energy, and was a major conceptual hurdle that we had to get over to proceed into modern physics.
Hmm..That's not how I read it. Most of ver villians were men of power or influence, and she had her hero refuse the Presidency without a moment's hesitation.
That's a testable hypothesis - the data wold then be associated with large, fresh impact craters. It's not clear from the article that this is the case.
At points where the craft is nearer the sun, more power is available - lots more power.
When you get close to the sun, solar arrays have a certain problem - they get hot, and hot solar arrays are much less efficient. If you look at MESSENGER's solar arrays, you'll see that most of the solar array area is taken up with reflectors to keep the solar array from overheating.
It's actually very difficult designing a planetary rendezvous mission with very low thrust engine. I'm not even sure how you'd do it. Sure, you can use gravity assists in some cases (e.g. Galileo, Cassini, and now MESSENGER), but this helps a chemical propulsion mission as well, and doesn't solve the problem of how you match speeds with the planet. Even with 6 gravity assists, MESSENGER still needs high thrust delta-Vs, and substantial at that.
Not power - specific impulse, which is effectively propellant ejection velocity.
Usually specific impulse is given in units of seconds, but this is an archaic convention - it's really velocity (they divide by the acceleration of gravity at ea level to get seconds).
There are two major problems with ion propulsion - ion thrusters need Kilowatts of power to operate (and so drive the design, mass and cost of the power subsystem), and they have very low thrust. They are also expensive and have limited life. So with ion propulsion, like everything else in engineering; if it's not necessary to do it, then it's necesary NOT to do it.
He's also a hardass, which you need to survive in a very tough market. That, and an expert salesman to the Apple faithful and developers.
His biggest problem has been converting the great unwashed of Windows users, and in fact, he's shyed away from being part of Apple advertising to the general public - and probably on good advice.
Most spacecraft thermal designs are to some extent passive, including MESSENGER. They are using some heat pipes - where it makes sense to use them to minimize heater power. Some of the heaters use software control, but most use series-redundant thermostats - they won't come on inadvertantly unless 2 thermostats fail - a very unlikely occurrence for space-qualified thermostats. If a heater fails, it has a backup.
For that sort of observatory, schedule is not a top priority. Nor was it for Hubble. Performance is so critical (and so difficult), that it's ready when it's ready - you just hope you can keep a lid on costs.
Once in free space, it all boils down to energy. If you want to escape the earth, you need a net positive energy. Take the derivative of the 2-body energy wrt velocity, and you can see that the best place to add energy is close to the planet. So, if you;re going to escape, escape quickly.
Nothing in propulsion is easy. Some folks can make it look easy; the way Barry Sanders made evading a pro linebacker look easy. However, you wouldn't be likely to succeed yourself.
Don't add at high speeds. If A and B are both moving away from me in opposite directions at 0.6c, they they are NOT moving at 1.2c relative to each other.
By "fixed point" I assuemt you mean at rest in an inertial frame. There are no fixed points in special relativity.
I don't think they're so strange. Mars isn't like Earth for several reasons, but one of the most important is that volcanic and tectonic activity stopped a very long time ago on Mars, and the surface water has mostly likely been gone for more than 2 billion years. Unlike Earth, rocks on Mars mostly just sit there for eons, undergoing slow weathering by wind and dust. This weathering can poke holes in rocks and create all sorts of odd shapes.
Is there any analysis even referenced on Hoagland's site that goes into this? No. If it looks like it might be a piece of ancient mars junk, and not a rock, then that must be what it is.
As to the "fossil", there's no conspiracy here. It didn't really pass muster as a fossil, and was already as well documented as it was going to get. Lots of other non-biological processes could have done what we see there. Also, if there's one fossil , there are many, so future fossil-hunting expeditions (which is not what MER is) wil find them if they're there. MER is all about learning what sort of sites are promising for such a hunt- and just as importantly, which sites are NOT.
If fossils are found on Mars (I think they will be), they will very likely be much smaller than anything that could be resolved with the MI.
I'm not sure I'd give this the status of theory. The problem is that it would very likely takes 10s of millions of years or longer to make the trip. While this is little doubt that this trip has been made, the survival of microorganisms or even spores over those time scales is dubious on a good day.
Consumer Reports recently published an article that came to about the same conclusions. However, they think LCD prices are going to come down dramatically soon.
If I buy a new TV this year, it will be a CRT. Possible exception: for the living room, where we don't really want a large TV, we may just put a 20" iMac with a small external video tuner.
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But e=mc^2 is special relativity, and you can derive it with high school math (they still teach math in high school, right?). Historically, it broke down the wall of separation between matter and energy, and was a major conceptual hurdle that we had to get over to proceed into modern physics.
If you write Newton's laws with the covariant 4-momentum, don't they still hold (pdot = Force)?
I see. That makes sense.
I can also see why Apple would object (takes business away from ITMS), but it could be construed as unfairly stifling competition as well.
I play non-DRM'ed mp3s on my iPod mini all the time. What am I missing?
Hmm..That's not how I read it. Most of ver villians were men of power or influence, and she had her hero refuse the Presidency without a moment's hesitation.
That's a testable hypothesis - the data wold then be associated with large, fresh impact craters. It's not clear from the article that this is the case.
When you get close to the sun, solar arrays have a certain problem - they get hot, and hot solar arrays are much less efficient. If you look at MESSENGER's solar arrays, you'll see that most of the solar array area is taken up with reflectors to keep the solar array from overheating.
It's actually very difficult designing a planetary rendezvous mission with very low thrust engine. I'm not even sure how you'd do it. Sure, you can use gravity assists in some cases (e.g. Galileo, Cassini, and now MESSENGER), but this helps a chemical propulsion mission as well, and doesn't solve the problem of how you match speeds with the planet. Even with 6 gravity assists, MESSENGER still needs high thrust delta-Vs, and substantial at that.
Probably - JPL had a "Space Mechanics" tutorial online once - probably still do.
Not power - specific impulse, which is effectively propellant ejection velocity.
Usually specific impulse is given in units of seconds, but this is an archaic convention - it's really velocity (they divide by the acceleration of gravity at ea level to get seconds).
There are two major problems with ion propulsion - ion thrusters need Kilowatts of power to operate (and so drive the design, mass and cost of the power subsystem), and they have very low thrust. They are also expensive and have limited life. So with ion propulsion, like everything else in engineering; if it's not necessary to do it, then it's necesary NOT to do it.
He's also a hardass, which you need to survive in a very tough market. That, and an expert salesman to the Apple faithful and developers.
His biggest problem has been converting the great unwashed of Windows users, and in fact, he's shyed away from being part of Apple advertising to the general public - and probably on good advice.
Most spacecraft thermal designs are to some extent passive, including MESSENGER. They are using some heat pipes - where it makes sense to use them to minimize heater power. Some of the heaters use software control, but most use series-redundant thermostats - they won't come on inadvertantly unless 2 thermostats fail - a very unlikely occurrence for space-qualified thermostats. If a heater fails, it has a backup.
Worst Movie. Evar.
For that sort of observatory, schedule is not a top priority. Nor was it for Hubble. Performance is so critical (and so difficult), that it's ready when it's ready - you just hope you can keep a lid on costs.
Everything the government does is motivated by politics. That's just life in the big city. How you eshpae and exploit that is the whole trick.
Non-sequitur.
More about what? More about astronomy - sure. But more about colonizing space and exploiting space resources? No. Why does it need to be either/or?
Once in free space, it all boils down to energy. If you want to escape the earth, you need a net positive energy. Take the derivative of the 2-body energy wrt velocity, and you can see that the best place to add energy is close to the planet. So, if you;re going to escape, escape quickly.
Nothing in propulsion is easy. Some folks can make it look easy; the way Barry Sanders made evading a pro linebacker look easy. However, you wouldn't be likely to succeed yourself.
Don't add at high speeds. If A and B are both moving away from me in opposite directions at 0.6c, they they are NOT moving at 1.2c relative to each other.
By "fixed point" I assuemt you mean at rest in an inertial frame. There are no fixed points in special relativity.
Please explain the downside of SUVs plunging off cliffs...
I don't think they're so strange. Mars isn't like Earth for several reasons, but one of the most important is that volcanic and tectonic activity stopped a very long time ago on Mars, and the surface water has mostly likely been gone for more than 2 billion years. Unlike Earth, rocks on Mars mostly just sit there for eons, undergoing slow weathering by wind and dust. This weathering can poke holes in rocks and create all sorts of odd shapes.
Is there any analysis even referenced on Hoagland's site that goes into this? No. If it looks like it might be a piece of ancient mars junk, and not a rock, then that must be what it is.
As to the "fossil", there's no conspiracy here. It didn't really pass muster as a fossil, and was already as well documented as it was going to get. Lots of other non-biological processes could have done what we see there. Also, if there's one fossil , there are many, so future fossil-hunting expeditions (which is not what MER is) wil find them if they're there. MER is all about learning what sort of sites are promising for such a hunt- and just as importantly, which sites are NOT.
If fossils are found on Mars (I think they will be), they will very likely be much smaller than anything that could be resolved with the MI.
Puny Earthling, your universe is just a spacetime bubble in someone's lab. As soon as your creator defends his thesis, you're out of here.
Couldn't be a tire track - too small, and not whre they drove.
On the other hand, it could be lots of things other than a fossil. This Hoagland person is the grand high poobah of wishful thinking.
This is mildly OT, but is there an accepted name fot this fallacy? I want to shoot one, have it stuffed, and mount it over my fireplace.
I'm not sure I'd give this the status of theory. The problem is that it would very likely takes 10s of millions of years or longer to make the trip. While this is little doubt that this trip has been made, the survival of microorganisms or even spores over those time scales is dubious on a good day.
Consumer Reports recently published an article that came to about the same conclusions. However, they think LCD prices are going to come down dramatically soon.
If I buy a new TV this year, it will be a CRT. Possible exception: for the living room, where we don't really want a large TV, we may just put a 20" iMac with a small external video tuner.