On the Mission status page they say that Pioneer 10 is heading towards Aldebaran of the Taurus constellation and will reach it in about 2 million years (Aldebaran is 68 lightyears away).
Yes, but you can stop the _majority_ of people that do not know enough about the net to get what they want. You can also discourage those that have enough knowledge (using legal threat).
The choice of lasting material has also been discouraged in the recent past due to ecology concerns (they do not rot and disappear). Additionally, lasting goods are not always desired by customers as much, because the advances of technology make many products obsolete anyway.
I think that generally the products and traces of technically highly developed societies will be extremely hard to find (because they are designed for easy recycling). (The most extreme form would be bio-machinery.)
Yep right. Having constant maintenance it is much easier to have lasting machines. I'd really like to know of machines, that didn't have (or required) maintenance and still worked. Maybe some traps in egypt pyramids that still work ? Erosion and chemical reactions really get important if you don't have maintenance and the possibility to replace parts.
It's also interesting that even life has certain limits on "lifetime": for animals (including humans) it seems to be around 100 years (probably due to increasing number of errors in cell reproduction a.k.a. cancer). For plant it is much longer (several 1000 a), but they are less complex systems, AFAIK.
But even those biological systems have some degree of internal maintenance/parts replacement: cells die regularly and are replaced by new ones. This is really an astonishing mechanism (but it fails to work indefinitely). If we could find a way to make this mechanism more reliable (without disabling the killing of "bad" cells), we could probably prolong our lifetimes considerably.
Ah, the Long Now Foundation. I already heard of them, but never botherd to examine it closer. What I found interesting is the following:
"The real problem is people. If something becomes unimportant to people, it gets scrapped for parts; if it becomes important, it turns into a symbol and must eventually be destroyed. The only
way to survive over the long run is to be made of materials large and worthless, like
Stonehenge and the Pyramids, or to become lost."
I think the constraint on their design to use only bronze age technology is too restrictive. Maybe stonehenge is an ancient version of a bronze-age technology Long Now Clock ?
This chaos thing makes for some nice example how space science can contribute to solving problems on earth (here: signal processing) without having been designed for that exact purpose initially. Of course, this holds for almost all science...many findings turn out to be useful in unexpected ways.
I'd really like to know what other machines have long lifetimes. Apparently ships have a long lifetime (I suppose several decades, how long exactly ?). Some steam engines (trains) also still work. Then there are probably a number of clocks that run for a long time as well.
Does anyone know of specific examples for these ?
Any other machine types ?
Provide a testbed for developing 21 st Century technology.
How exactly? Give me examples, reasons or some good links to these. Plenty of 21st century technology is already developed on the ground. I doubt there will actually be a huge amount of 21st century technology used in the station on the grounds that in space where just about everything everything is critical tried-and-trusted technology is used.
I think by "21st century technology" they mean technology that relies on space (as opposed to 20th century technology which can be done on ground), rather than technology that is _used_ in space.
One example of such technology is the Space Vacuum Epitaxy Center. They define themselves: "The Space Vacuum Epitaxy Center creates advanced thin film materials and devices for commercial applications through growth technologies using terrestrial and space environments".
They operate a so called Wake Shield Facility: "The WSF is a 12-foot diameter stainless disk-shaped platform launched from the Space Shuttle that creates a unique ultra vacuum environment in its wake, with a combination of pumping speeds and vacuum levels thousands of times better than the best vacuum chambers on earth. Built for eventual long-term autonomous operation, the WSF supports all of the processing and characterization instrumentation required for advanced molecular and chemical beam epitaxy (MBE/CBE) materials processing."
On the role of the ISS for their business they say: "The ISS is the linchpin in long term WSF business planning, serving as the logistics and servicing node in a manufacturing process that will make the Wake Shield Facility a profitable International Space Station commercial tenant."
How is this "Informative" ? I'd rather moderate it "Uninformed".
May I cite "ISS Familiarization, ISS FAM C 21109":
1.2 Purpose, Objectives, and Organization of the ISS
The purpose of the ISS is to provide an "Earth orbiting facility that houses experiment payloads,
distributes resource utilities, and supports permanent human habitation for conducting research
and science experiments in a microgravity environment." (ISSA IDR no. 1, Reference Guide,
March 29, 1995)
This overall purpose leads directly into the following specific objectives of the ISS program:
Develop a world-class orbiting laboratory for conducting high-value scientific research
Provide access to microgravity resources as early as possible in the assembly sequence
Develop ability to live and work in space for extended periods
Develop effective international cooperation
Provide a testbed for developing 21 st Century technology.
Here is a link that describes the scientific objectives.
zone of exclusion = the part of low earth orbit that has no relay satellite and ground link coverage due to the curvature of earth and the position of those facilities.
structural blockage outages = communication outage due to ISS structure itself being in the signal path (approx 30% per orbit for the completed ISS)
So, the communication outage recorder is vital unless you want important data to disappear in/dev/space/null. Doesn't sound pointless to me.
You are right. They have tons of high quality pictures in the Gallery. I like to have them as desktop background images.
Re:(Standardized) Tests
on
Watch Camera
·
· Score: 1
In our physics tests at (a German) university, we were allowed up to one letter size sheet of paper for "cheating" (double sided, as small as you could write). Of course, preparing that paper made you go through all of that lecture and helped you that way. The problems posed were slightly different from what we have seen before anyway, so you could not just copy the solution from the notes. Knowledge of formula was not a primary concern, you had to understand the concepts/relations.
I remember my english teacher at school also encouraged us to write cheating notes (we were not allowed to use them though).
ISS is slowed down and thus loses altitude by atmospheric drag. It needs to be "reboosted" to a higher orbit every few months (which will ususally be done by visiting spacecraft). This is normal and it was designed that way. The upper limit of 400km altitude is due to the limited range of the visiting spacecraft (range depending on payload mass). The lower limit is due to the requirement that the ISS must not sink to a dangerously low orbit even if one reboost cycle is missed.
The relevant variable is the molecule mass. The lower the mass, the higher the mean velocity of a molecule at a given temperature. The reason for this is, that in a gas all molecules have the same mean kinetic energy E=3/2kT (T=temperature). So because of E=1/2*m*v^2 the lighter molecules need a higher velocity to have the same energy.
Now CO2 has m = 12+16+16 = 44 amu, while H2O has only m = 1+1+16 = 18 amu (atomic mass unit).
"Let's wait until we know more about the Martian ecosystem, if there is one, and until we know more about our own ecosystem."
But that is exactly what we are doing. Scientists are _discussing_ ways to terraform mars - nobody is going to start terraforming it tomorrow. The chemistry of earths atmosphere is much more complicated than mars' because it depends on the biosphere (whose effects are very hard to quantify). Plus, there is not much to destroy on mars (no biosphere) - if temperature goes up one or two degree it really doesn't lead to rise of sea level or such. Of course, we should first search mars for biosphere before we are going to destroy it - it would give us very valuabale scientific insights. But IMO we shouldn't give up mars just because some bacteria sit on it.
They mention this in the artice. It would take 100000 years. What they want to do is raise the pressure and temperature so one doesn't need pressure suits but only oxygen masks.
The new launch time is today 7:17 EDT (23:17 GMT).
They already have removed the pin (had to drain the oxygen and hydrogen before they could remove it).
The full detailed story.
When they say "Aleph" or "Delphi" they really mean a collaboration of several hundred scientists from many different universities each (e.g. Delphi = 550 physicists from 56 universities). They operate the "Aleph" or "Delphi" Detectors (which have approx. the size of a gym).
You can easily spot HEP papers by looking for those that have author lists of two pages.
No wonder they had to invent WWW to communicate!
A list of all CERN groups/experiments. Visit their homepages; they have some nice pictures and explanations.
I found your post(#118) interesting. Just one question: why is MgF preferred over KBr ? The latter seems to be often used as window for IR-spectroscopy machines. Is it the fact that there exists a glassy phase for MgF ?
As a sidenote: Sapphire is the material of choice in UHV (ultra high vacuum) applications when you need good thermal conductivity at low temperatures (below room temp.) and low electrical conductivity (insulator) at the same time (It's used as a spacer).
Sapphire is also used as a substrate for deposition of thin films. I don't have experience in that field, however.
Then there are of course Ti:Sapphire Lasers (Sapphire doped with Ti), their strength is the huge tuning range (1000nm - 660nm). The very first Laser back in 1960 was also based on Sapphire, more precise it was Cr:Sapphire, also known as ruby.
The problem with Sapphire is, that is so hard and thus you need diamond to work it. Even then you have to proceed very slowly. Making a hole in a piece Sa can take hours and will cost considerable machine time.
Slashdot Mirror
On the Mission status page they say that Pioneer 10 is heading towards Aldebaran of the Taurus constellation and will reach it in about 2 million years (Aldebaran is 68 lightyears away).
The "Open Source" concept is common in science for several centuries now.
You cannot stop people from doing what they want.
Yes, but you can stop the _majority_ of people that do not know enough about the net to get what they want. You can also discourage those that have enough knowledge (using legal threat).
The choice of lasting material has also been discouraged in the recent past due to ecology concerns (they do not rot and disappear). Additionally, lasting goods are not always desired by customers as much, because the advances of technology make many products obsolete anyway.
I think that generally the products and traces of technically highly developed societies will be extremely hard to find (because they are designed for easy recycling). (The most extreme form would be bio-machinery.)
Yep right. Having constant maintenance it is much easier to have lasting machines. I'd really like to know of machines, that didn't have (or required) maintenance and still worked. Maybe some traps in egypt pyramids that still work ? Erosion and chemical reactions really get important if you don't have maintenance and the possibility to replace parts.
It's also interesting that even life has certain limits on "lifetime": for animals (including humans) it seems to be around 100 years (probably due to increasing number of errors in cell reproduction a.k.a. cancer). For plant it is much longer (several 1000 a), but they are less complex systems, AFAIK.
But even those biological systems have some degree of internal maintenance/parts replacement: cells die regularly and are replaced by new ones. This is really an astonishing mechanism (but it fails to work indefinitely). If we could find a way to make this mechanism more reliable (without disabling the killing of "bad" cells), we could probably prolong our lifetimes considerably.
Ah, the Long Now Foundation. I already heard of them, but never botherd to examine it closer. What I found interesting is the following:
"The real problem is people. If something becomes unimportant to people, it gets scrapped for parts; if it becomes important, it turns into a symbol and must eventually be destroyed. The only
way to survive over the long run is to be made of materials large and worthless, like
Stonehenge and the Pyramids, or to become lost."
I think the constraint on their design to use only bronze age technology is too restrictive. Maybe stonehenge is an ancient version of a bronze-age technology Long Now Clock ?
This chaos thing makes for some nice example how space science can contribute to solving problems on earth (here: signal processing) without having been designed for that exact purpose initially. Of course, this holds for almost all science...many findings turn out to be useful in unexpected ways.
I'd really like to know what other machines have long lifetimes. Apparently ships have a long lifetime (I suppose several decades, how long exactly ?). Some steam engines (trains) also still work. Then there are probably a number of clocks that run for a long time as well.
Does anyone know of specific examples for these ?
Any other machine types ?
Provide a testbed for developing 21 st Century technology.
How exactly? Give me examples, reasons or some good links to these. Plenty of 21st century technology is already developed on the ground. I doubt there will actually be a huge amount of 21st century technology used in the station on the grounds that in space where just about everything everything is critical tried-and-trusted technology is used.
I think by "21st century technology" they mean technology that relies on space (as opposed to 20th century technology which can be done on ground), rather than technology that is _used_ in space.
One example of such technology is the Space Vacuum Epitaxy Center. They define themselves: "The Space Vacuum Epitaxy Center creates advanced thin film materials and devices for commercial applications through growth technologies using terrestrial and space environments".
They operate a so called Wake Shield Facility: "The WSF is a 12-foot diameter stainless disk-shaped platform launched from the Space Shuttle that creates a unique ultra vacuum environment in its wake, with a combination of pumping speeds and vacuum levels thousands of times better than the best vacuum chambers on earth. Built for eventual long-term autonomous operation, the WSF supports all of the processing and characterization instrumentation required for advanced molecular and chemical beam epitaxy (MBE/CBE) materials processing."
On the role of the ISS for their business they say: "The ISS is the linchpin in long term WSF business planning, serving as the logistics and servicing node in a manufacturing process that will make the Wake Shield Facility a profitable International Space Station commercial tenant."
A range of other projects can be found at Space Product Development.
Information on Commercial development on ISS can be found at http://commercial.hq.nasa.gov/
How is this "Informative" ? I'd rather moderate it "Uninformed".
May I cite "ISS Familiarization, ISS FAM C 21109":
1.2 Purpose, Objectives, and Organization of the ISS
The purpose of the ISS is to provide an "Earth orbiting facility that houses experiment payloads,
distributes resource utilities, and supports permanent human habitation for conducting research
and science experiments in a microgravity environment." (ISSA IDR no. 1, Reference Guide,
March 29, 1995)
This overall purpose leads directly into the following specific objectives of the ISS program:
Develop a world-class orbiting laboratory for conducting high-value scientific research
Provide access to microgravity resources as early as possible in the assembly sequence
Develop ability to live and work in space for extended periods
Develop effective international cooperation
Provide a testbed for developing 21 st Century technology.
Here is a link that describes the scientific objectives.
zone of exclusion = the part of low earth orbit that has no relay satellite and ground link coverage due to the curvature of earth and the position of those facilities.
/dev/space/null. Doesn't sound pointless to me.
structural blockage outages = communication outage due to ISS structure itself being in the signal path (approx 30% per orbit for the completed ISS)
So, the communication outage recorder is vital unless you want important data to disappear in
You are right. They have tons of high quality pictures in the Gallery. I like to have them as desktop background images.
In our physics tests at (a German) university, we were allowed up to one letter size sheet of paper for "cheating" (double sided, as small as you could write). Of course, preparing that paper made you go through all of that lecture and helped you that way. The problems posed were slightly different from what we have seen before anyway, so you could not just copy the solution from the notes. Knowledge of formula was not a primary concern, you had to understand the concepts/relations.
I remember my english teacher at school also encouraged us to write cheating notes (we were not allowed to use them though).
ISS is slowed down and thus loses altitude by atmospheric drag. It needs to be "reboosted" to a higher orbit every few months (which will ususally be done by visiting spacecraft). This is normal and it was designed that way. The upper limit of 400km altitude is due to the limited range of the visiting spacecraft (range depending on payload mass). The lower limit is due to the requirement that the ISS must not sink to a dangerously low orbit even if one reboost cycle is missed.
here is some cut'n paste from the Mars Fact Sheet:
Martian Atmosphere
Surface Pressure: ~6.1 mb (variable) [6.9 mb to 9 mb (Viking 1 Lander site)]
Surface Density: ~0.020 kg/m3
Scale height: 11.1 km
Average temperature: ~210 K
Diurnal temperature range: 184 K to 242 K (Viking 1 Lander site)
Wind speeds: 2-7 m/s (summer), 5-10 m/s (fall), 17-30 m/s (dust storm) (Viking Lander sites)
Mean molecular weight: 43.34 g/mole
Atmospheric composition (by volume):
Major : Carbon Dioxide (CO2) - 95.32% ; Nitrogen (N2) - 2.7%
Argon (Ar) - 1.6%; Oxygen (O2) - 0.13%; Carbon Monoxide (CO) - 0.08%
Minor (ppm): Water (H2O) - 210; Nitrogen Oxide (NO) - 100; Neon (Ne) - 2.5;
Hydrogen-Deuterium-Oxygen (HDO) - 0.85; Krypton (Kr) - 0.3;
Xenon (Xe) - 0.08
Actually, I once fell from the chair while playing Half Life because I tried to duck away.
When I feel the urge for a really complex game with super sharp gfx, I try real life. It only lacks possibility to restart from a saved game.
The relevant variable is the molecule mass. The lower the mass, the higher the mean velocity of a molecule at a given temperature. The reason for this is, that in a gas all molecules have the same mean kinetic energy E=3/2kT (T=temperature). So because of E=1/2*m*v^2 the lighter molecules need a higher velocity to have the same energy.
Now CO2 has m = 12+16+16 = 44 amu, while H2O has only m = 1+1+16 = 18 amu (atomic mass unit).
"Let's wait until we know more about the Martian ecosystem, if there is one, and until we know more about our own ecosystem."
But that is exactly what we are doing. Scientists are _discussing_ ways to terraform mars - nobody is going to start terraforming it tomorrow. The chemistry of earths atmosphere is much more complicated than mars' because it depends on the biosphere (whose effects are very hard to quantify). Plus, there is not much to destroy on mars (no biosphere) - if temperature goes up one or two degree it really doesn't lead to rise of sea level or such. Of course, we should first search mars for biosphere before we are going to destroy it - it would give us very valuabale scientific insights. But IMO we shouldn't give up mars just because some bacteria sit on it.
They mention this in the artice. It would take 100000 years. What they want to do is raise the pressure and temperature so one doesn't need pressure suits but only oxygen masks.
The new launch time is today 7:17 EDT (23:17 GMT). They already have removed the pin (had to drain the oxygen and hydrogen before they could remove it). The full detailed story.
When they say "Aleph" or "Delphi" they really mean a collaboration of several hundred scientists from many different universities each (e.g. Delphi = 550 physicists from 56 universities). They operate the "Aleph" or "Delphi" Detectors (which have approx. the size of a gym).
You can easily spot HEP papers by looking for those that have author lists of two pages.
No wonder they had to invent WWW to communicate!
A list of all CERN groups/experiments. Visit their homepages; they have some nice pictures and explanations.
But your telescope does not collect cosmic dust, or does it ?
I found your post(#118) interesting. Just one question: why is MgF preferred over KBr ? The latter seems to be often used as window for IR-spectroscopy machines. Is it the fact that there exists a glassy phase for MgF ?
As a sidenote: Sapphire is the material of choice in UHV (ultra high vacuum) applications when you need good thermal conductivity at low temperatures (below room temp.) and low electrical conductivity (insulator) at the same time (It's used as a spacer).
Sapphire is also used as a substrate for deposition of thin films. I don't have experience in that field, however.
Then there are of course Ti:Sapphire Lasers (Sapphire doped with Ti), their strength is the huge tuning range (1000nm - 660nm). The very first Laser back in 1960 was also based on Sapphire, more precise it was Cr:Sapphire, also known as ruby.
The problem with Sapphire is, that is so hard and thus you need diamond to work it. Even then you have to proceed very slowly. Making a hole in a piece Sa can take hours and will cost considerable machine time.