The focus of this story is completely wrong. Ion propulsion is kinda old hat, there has been more than just 'a handful' of satellites flying with some form of it, unless your hand is really big.
Granted, most of them have been as a secondary propulsion mode and for stationkeeping, but now it is also increasingly being taken up as primary probpulsion for deep space missions.
What is really interesting is the satellite GOCE.
Tasked with mapping out the gravitational pull of earth with very high fidelity, it needs to fly as close to the earth as possible without being dragged out of orbit by the athmosphere, and to remain stable in this very low orbit.
For this reason this is the only satellite I know of where a major design driver was that it be aerodynamic!
The ion propulsion is primarily to counteract the constant drag so the satellite maintains it's orbit, and to this end it is projected to be thrusting almost continuously.
Whatever you might say about this mission, it certainly is exciting. I can't recall any other with such a level of failures and malfunctions, yet still with a hope, if at this point slim, of succeeding (Maybe SOHO has had an equal number of near death experiences over a much longer time span).
But you don't deny that the Oregon Bison is a resource that IS exhausted? Your argument is that resources that are percieved as insignificant in the present, can casually be drained. I find that attitude problematic. Future knowledge could very well show a hitherto ignored entity to be a very important factor in some value fostering scheme.
Thre ariane 5 standard is able to put about a 3 metric tonne payload on a moon rendezvous. The reason the Smart-1 was put in orbit the way it was, was simply because the probe was one of three sattelites, two of which were destined for geostationary orbit (All of course in order to save cash).
Just some minor nits that I'm here to pick; The sr-71 Blackbird were (is?) also able to cruise for hours far above the speed of sound. Its engines operated in a slightly different way than most other jets by technically operating with afterburner when flying high mach numbers, but actually achieving its best mileage in this mode!
Other planes than the ones you mention have indeed been able to truly fly above mach 1 without reheat, and today, at least the eurofighter is able to do just that.
Regarding the f-22, I seem to remember having read somewhere, that due to the fact that the plane has no variable geometry intakes, the possibility of it both being effective at low speed, and at over mach 2, is quite low, the conclusion being as far as i remember, that the f-22 probably cannot go significantly faster than mach 2
You would try to observe the gavitational effects of your theorized planet on visible objects. Just like astronomers have done for hundreds of years with non visible planets/heavenly bodies.
But it should also be noted that mercury is a very difficult planet when it comes to sending probes. There is some significant problems with the orbital mechanics of sending something from the earth and *towards* the gravity well that is the sun, with the objective of making it orbit the planet. Furthermore of course, any probe would have to be ready for some *serious* radiation over a prolonged period. Nonetheless, there are actually two probes in the works, that should arrive at mercury in 2016, for the BepiColombo, and in 2007-9 for the Messenger probe.
I will not argue with you about the possible degree of manipulation of the images, since arguments in such a discussion will be based on perceptions rather than clearcut facts, and I do not wish to get involved in a discussion of that type. Besides, I have no real experience with the sight of a planet when in orbit as I work neither for NASA or Rosaviakosmos:).
As to the visual differences to other cameras, the only argument i can come up with is that the HRSC is a colour camera. I would just imagine that would make some sort of a difference but my knowledge is limited.
Now the question of wether some of the MEX images have been "reprojected in 3D" is not really a question, as you said, and i did not argue with that, the only thing we disagree on is the wording; I thought that reprojection meant that a flat 2D image was 'painted' onto a 3d topographic map, as has been done with images from some of the US probes. When MEX collects data, it not only records the colour of the pixel, but also determines the 3D position of the pixel, and from these data, one can generate computerized images from several different angles of the surface.
To the best of my knowledge, the colours are true. All pics from the HRSC on Mars Express are (except when they are going to post pics with data only from the super resolution channel, which will all be in black/white), but there is a possibility that the calibration of the camera is not yet precise (Lots, if not all of the released material was taken for calibration purposes)
So there may be some 'biases' in the pictures, but not intentionally.
As for the 3d, the camera uses a very smart method to get both forward, downward, and backwards imaging of a given pixel and this is sufficient to create a computer generated picture of the landscape from almost any angle. The pictures are not projections of imaging onto altitude data from other satellites or something of the sort. The shading is as the camera saw it.
(I am not afilliated with the people who built the camera, I am just an interested onlooker. Info in this post may be inaccurate, but is, to the best of my knowledge, not. Try this page for a brief intro to the camera).
I would say that is the smallest "big list of all spacecraft" I have ever seen. A more comprehensive resource on spacecraft, be it manned, planetary or ordinary telcomms, is the ever-useful www.astronautix.com. Go here for a full list sorted by type of mission. (scroll down to 'planetary' for the interesting stuff).
Actually I believe many of the astronauts on the ISS claim that the loss of bone mass has been drastically reduced with the kinds of excercises they are doing on a daily basis. Although the problem hasn't been completely eleminated read for example this letter from expedition 7 crewmember Ed Lu.
"We have some indications that we may be close to solving the problem. In fact, one of our main goals this mission is to see if we can replicate the very good results obtained by some previous ISS crew members in preventing bone and muscle loss"
I remember seeing an article about an experiment with a special low-noise asphalt which had been applied to a perticularly noisy road here (Copenhagen).
It was about a year ago, I wonder whatever happened to that, and has anybody else heard about anything similar? Any ideas as to how such an asphalt would work?
But this discussion actually reveals one of the core differences between the european and the USian mindset.
While on one hand the european thinks that, given a problem that is experienced by a sufficiently large number of the population, then it is a problem that should be solved by the society as a whole, the american on the other hand, believes that it is the individual's responsibility to cope with most problems even though they aren't neccesarily problems that are easily remedied by single persons.
(Crass generalisation I know)
Slashdot Mirror
The focus of this story is completely wrong. Ion propulsion is kinda old hat, there has been more than just 'a handful' of satellites flying with some form of it, unless your hand is really big. Granted, most of them have been as a secondary propulsion mode and for stationkeeping, but now it is also increasingly being taken up as primary probpulsion for deep space missions.
What is really interesting is the satellite GOCE.
Tasked with mapping out the gravitational pull of earth with very high fidelity, it needs to fly as close to the earth as possible without being dragged out of orbit by the athmosphere, and to remain stable in this very low orbit.
For this reason this is the only satellite I know of where a major design driver was that it be aerodynamic! The ion propulsion is primarily to counteract the constant drag so the satellite maintains it's orbit, and to this end it is projected to be thrusting almost continuously.
Whatever you might say about this mission, it certainly is exciting. I can't recall any other with such a level of failures and malfunctions, yet still with a hope, if at this point slim, of succeeding (Maybe SOHO has had an equal number of near death experiences over a much longer time span).
The Rockot consists of 3 stages, the ss-19 1st and 2nd stage, (hundreds of succesful test firings) and the breeze M 3rd stage (fairly new).
But you don't deny that the Oregon Bison is a resource that IS exhausted? Your argument is that resources that are percieved as insignificant in the present, can casually be drained. I find that attitude problematic. Future knowledge could very well show a hitherto ignored entity to be a very important factor in some value fostering scheme.
But that's not really many mistakes is it? For a text 9 peragraphs long...
Well the usual trend is, the richer the family, the fewer the kids...
Thre ariane 5 standard is able to put about a 3 metric tonne payload on a moon rendezvous. The reason the Smart-1 was put in orbit the way it was, was simply because the probe was one of three sattelites, two of which were destined for geostationary orbit (All of course in order to save cash).
You mean... we're all... INSIDE AREA 51!!
Well nothing to do now but to search for the aliens..
AHA!
Just bear in mind it is only a conceptual design at this point, and the funding is... well, difficult.
Just some minor nits that I'm here to pick; The sr-71 Blackbird were (is?) also able to cruise for hours far above the speed of sound. Its engines operated in a slightly different way than most other jets by technically operating with afterburner when flying high mach numbers, but actually achieving its best mileage in this mode!
Other planes than the ones you mention have indeed been able to truly fly above mach 1 without reheat, and today, at least the eurofighter is able to do just that.
He did mention "Il Jong"...
Regarding the f-22, I seem to remember having read somewhere, that due to the fact that the plane has no variable geometry intakes, the possibility of it both being effective at low speed, and at over mach 2, is quite low, the conclusion being as far as i remember, that the f-22 probably cannot go significantly faster than mach 2
Well.. They *are* a third of the way to the moon, so 'close' is a relative term :)
You would try to observe the gavitational effects of your theorized planet on visible objects. Just like astronomers have done for hundreds of years with non visible planets/heavenly bodies.
But it should also be noted that mercury is a very difficult planet when it comes to sending probes. There is some significant problems with the orbital mechanics of sending something from the earth and *towards* the gravity well that is the sun, with the objective of making it orbit the planet. Furthermore of course, any probe would have to be ready for some *serious* radiation over a prolonged period. Nonetheless, there are actually two probes in the works, that should arrive at mercury in 2016, for the BepiColombo, and in 2007-9 for the Messenger probe.
And a derivative of the rd-170 engine used on the zenit, the rd-180, is also used on one of the to newest US launchers; the atlas 5
As to the visual differences to other cameras, the only argument i can come up with is that the HRSC is a colour camera. I would just imagine that would make some sort of a difference but my knowledge is limited.
Now the question of wether some of the MEX images have been "reprojected in 3D" is not really a question, as you said, and i did not argue with that, the only thing we disagree on is the wording; I thought that reprojection meant that a flat 2D image was 'painted' onto a 3d topographic map, as has been done with images from some of the US probes. When MEX collects data, it not only records the colour of the pixel, but also determines the 3D position of the pixel, and from these data, one can generate computerized images from several different angles of the surface.
As for the 3d, the camera uses a very smart method to get both forward, downward, and backwards imaging of a given pixel and this is sufficient to create a computer generated picture of the landscape from almost any angle. The pictures are not projections of imaging onto altitude data from other satellites or something of the sort. The shading is as the camera saw it.
(I am not afilliated with the people who built the camera, I am just an interested onlooker. Info in this post may be inaccurate, but is, to the best of my knowledge, not. Try this page for a brief intro to the camera).
I am an asshole. The page haven't even stopped loading before I started spouting crap.
I would say that is the smallest "big list of all spacecraft" I have ever seen. A more comprehensive resource on spacecraft, be it manned, planetary or ordinary telcomms, is the ever-useful www.astronautix.com. Go here for a full list sorted by type of mission. (scroll down to 'planetary' for the interesting stuff).
30 metres? Ha! So you want big? I'll give you big. Link goes to a page about a proposed 100 metre telescope!
Sorry, wrong link, try this
Actually I believe many of the astronauts on the ISS claim that the loss of bone mass has been drastically reduced with the kinds of excercises they are doing on a daily basis. Although the problem hasn't been completely eleminated read for example this letter from expedition 7 crewmember Ed Lu. "We have some indications that we may be close to solving the problem. In fact, one of our main goals this mission is to see if we can replicate the very good results obtained by some previous ISS crew members in preventing bone and muscle loss"
I remember seeing an article about an experiment with a special low-noise asphalt which had been applied to a perticularly noisy road here (Copenhagen). It was about a year ago, I wonder whatever happened to that, and has anybody else heard about anything similar? Any ideas as to how such an asphalt would work?
But this discussion actually reveals one of the core differences between the european and the USian mindset. While on one hand the european thinks that, given a problem that is experienced by a sufficiently large number of the population, then it is a problem that should be solved by the society as a whole, the american on the other hand, believes that it is the individual's responsibility to cope with most problems even though they aren't neccesarily problems that are easily remedied by single persons. (Crass generalisation I know)