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Unfortunately, the flesh of these things seems to hold a high amount of ammonia.

This link tells - among other things - about some dude that tried to cook a part of a giant squid.

That's one of the holy grails of oceanography, to catch a live Architeuthis seawifs.gsfc.nasa.gov

F-8 Digital Fly-By-Wire Aircraft

Sebastian's Comet Hunt is a great news site detailing SOHO comet discoveries, and there's links there that shows anyone (even tyros) how to pick these comets up.

Late this year, a few of my net acquaintances will be meeting in two spots (S. Africa & S. Australia) for the pending doom and end of the world... oh wait... its just a total eclipse.

There have been some examples where pendulums swing funny durring elipses. I want to see if I can recreate this and I'm looking for help to do it on the cheap. The current expirments show that a swinging uniform sphere will have some side forces on it. My problem is measuring things in the field. I can get temps to about .01C. I can get non-moving distances to about .1mm, I can get weight to about .1g but I can get time to a few nanoseconds so I need to devise and expierment that uses just time. I've been thinking that I can get a disk spinning, I should use a simple optical coupler (like whats in your mouse) and a good timing circut to get some very precise timings. Now if I can build a disk that is well balanced but non-uniform density, that means its angular speed should be effected by the same force thats pushing a pendulum slighty to its side. The problem is the pendulum will contine to rotate as the force is applied but my spinning device will only see the force when the force is applied to one side of the disk. The smaller the disk, the shorter this time is since the shadow of the moon is travling at a rate of about 500m/s. The phenomenon I'm looking for will happen twice for about .0002 seconds. If I miss it this time there will be another 7 chances over the next decade.

While the CNN article is truely hyped and mostly fluff there is an informative paper here.

In summary: If you find yourself in orbit around a Lagrange point you only need to change your velocity a little to change your orbit radically (thats the chaos part). The orbits you can enter in the Sun-Earth system is forming two horseshoes with the Earth placed in the gap (or perhaps more precisely: Like the figure 8 with the smallest of the loops folded within the larger one and the Earth placed in the cross between the loops). One of the orbits lies within earths orbit. The other lies outside of Earths orbit.

What makes this particular interesting is that the horseshoes of the Sun-Earth system overlaps the horseshoes of the Earth-Moon system. So, if you're travelling along one of the horseshoes in the Sun-Earth system, you can pull the trick again when you cross the horseshoe of the Earth-Moon system and enter an orbit around earth with virtually no fuel consumption. It works the other way around too: If you place a spaceship in one of the Lagrange points of the Earth-Moon system you can reach far into the solar system for almost free by entering the horseshoe of the Sun-Earth system at the right time. The only catch is that you're travelling pretty slow.

Now the CNN article talks a lot about interplanetian travel, but the reality is that the mechanics have only been worked out for the earth-moon-sun system and the Jovian system. Interplanetarian travel requires heavy computatios and is still in the works.

And to dispell some of the confusion in this thread about the nature of the Langrange points this page gives a good explanation.

If you do all the math it turns out there are 5 stable Lagrange points, two of which even allow a stable orbit around it.

Interesting concept but doesnt the slingshot effect use the gravity of planets (hence zero fuel ?) for travel ? Hence a path with nett gravity pulling the body to its destination would be of more use I think. Already the cassini mission used this principle to propel the craft to saturn (since the spacecraft lacked the fuel and the engines to propel itself to saturn).

-Dracken

What's that most universally observed and verified law? I think it's the law of biogenesis:
"Spontaneous generation (the emergence of life from nonliving matter) has never been observed. All observations have shown that life comes only from life. This has been observed so consistently it is called the law of biogenesis."

To the best of my knowledge, God has never been observed popping planets into existence either.

Before you answer that we weren't there to see it, remember that we weren't there to see the origins of life on earth either.

As far as I was aware, life has NEVER been created, even in a laboratory. Life always comes from life - this is universally observed and has never been proven false.

No, but then again, most laboratories are much smaller than the planet Earth, and most experiments have much less than a billion years in which to produce results. Probably the closest is the polio virus thing, but of course synthesizing DNA and RNA isn't really life from lifelessness because the reagents involved have to be obtained by biological processes, as well as the other proteins and such to complete the virus. It's something like the old quip about a scientist finally shouting to the heavens "I've discovered the secrets of life! Take that, God! I can create a man from dust just like you now." To which God replies, "Ok, but you'll have to make your own dust, you can't use mine."

Concerning amino acids, I was of course referring to the Urey-Miller experiments as well as some others. Here is an interesting tidbit concerning the possible formation of amino acids in deep space ice. There's even a bit of discussion of handedness, one of the major problems creationists have with any of these sorts of experiments. See, I read your link, even though I had to cut and paste and remove the space.

I don't like God being constrained by the simplistic fables of today - evolution.

First, evolutionary theory is hardly in the same category as creation mythology. There is a large amount of evidence that indicates it gives a reasonable explanation of the origins of life. From it, you can make general predictions about the fossil record which observations have agreed with many times. Reference the near-complete fossil record of whale evolution, the diversification of reptiles and mammals, the progress from Eohippus to the modern horse. Even humankind has an ancestral record - I'm sure if you're at all interested in the topic you know of the recent find in Kenya. It probably raises more questions than it answers, but that is the nature of science.

Sure, you can explain all the fossil evidence by saying "God did it", and answer the following "Why?" with "Because he wanted to." But, you haven't explained anything by that. Scientists can't use that kind of explanation to do any real work. Without some sort of testable theories that make useful predictions, we would never have had modern medicines, pesticides, or any sort of biotechnology (yes, some is good and some bad).

The same can be said of any sort of advance. If humans had just taken for granted that God created lightning, we'd never have harnessed electricity. In the process of understanding electricity, we've discovered the electron and come to a theory of how static electricity builds up in clouds and discharges. In the process, we've had to discard the idea that Thor throws his hammer down, or God creates it to strike down sinners. But, we've come to a new understanding of His universe that we can put to great use. I think the tradeoff is worthwhile. The same sort of tradeoffs are being made in biology. I can still say "God created life on earth" just as surely as I can say "God creates lightning", it's just that we now have a greater understanding of the process by which He did/does it.

Evolution is not a new idea. It has been around as long as the hills, I think, and will always exist in some form.

Well, even according to Genesis the hills existed before Adam did, so that can't be true. ;)

There are so many amazing things to be observed and contemplated, especially under a creationist model. It is useless to say what you just said - it's merely the subjective emotions of one man/woman.

When do you really appreciate a fine watch? Watching the hands go around the face is pretty, but you really have respect for the designer when you open it up and look at the finely crafted gears. But you're right, that's sort of an opinion thing. It's pretty undeniable, though, that if you want to learn anything about watch-making, you have to open the watch. This is why scientists tend towards evolutionary theory - it's not because they want to disprove God, but because the information they need to do their work just isn't in Genesis.

I think this has turned into the longest post I've ever put up here, and I've probably rambled far too much. I hope you don't get too bored reading it to give it a bit of thought.

It seems that there is a lot of electricity in India :-)

However, I am not at ease with all that Simputer stuff. There is much hype, but what's behind?

It looks too closed to succeed. You have to licence a 'design' which is not much more than an Arm-chip Application Note. All seems one-way (there seems to be no forum, no call for participation, just a couple of guys trying to exploit the (nice) idea of 'a computer for the poor', no SourceForge community, nand OpenHardware one or the likes. If you look at the Google/Open_Source/Simputer directory, it is just hype, there is no forum, no CVS repository.
When you look at Simputer.org, there is no activity (the pages are ages old) and it links you to similarily dead 'commercial' pages (where people don't answer when you ask for information).

Why not just start from a LART or one of the existing LinuxDevices?

Don't get me wrong. I'd be pleased to see a Simputer succeeds, but when you start by asking money for a 'class-room design' with no community support, I am not sure that 'a computer for the poor' is more than an empty dream.

Plus, the SR-71 would leave that anglo-french beer can suckin' it's con trails.

GO USA!

Boeing already built a vehicle with electric power and motors for each wheel, 30 years ago. It is, of course, the Apollo Lunar Rover--three were used on the Apollo 15, 16, and 17 missions.

(To my surprise, the LRV didn't use a fuel cell, though fuel cells were used for other applications on Apollo.)

Define "basic research".

• 1960: "FIRST" Re-Entry Glider
• 1961: "Feasibility Study of an Inflatable Type Stabilization and Deceleration System for High Altitude and High Speed Recovery"
• 1989: U.S. Patent 4,832,288. Cone-shaped inflatable reentry system.

Yes NASA uses 8086 and runs linux86 on them! Flight Linux

A good place to start would be to include whatever was on the Voyager spacecraft.

I wonder why they picked 50,000 years. I mean, you might as well say 80 gadzillion years. Why not just say "we'll do our best to make it last forever?"

That's why it's called rocket "science". If it were rocket "engineering" the success rate would be much higher.

A couple of references at this NASA site.

Here's NASA's orbital debris site. Check out Mitigate for their safety standard. One point to remember is that NASA isn't a regulatory agency, and so can only police itself.

Here's NASA's orbital debris site. Check out Mitigate for their safety standard. One point to remember is that NASA isn't a regulatory agency, and so can only police itself.

NASA is already using AeroGel in the StarDust mission to collect high-velocity particles.

Thick enough, it could be used to capture those tiny bolts and fragments they can't track by radar.

Also, one of their concerns about using lasers to zap bigger debris was the fear of generation bazillion smaller particles that couldn't be collected or tracked thereafter.

Why not create an autonomous robot that circles the globe, zap the objects it can while collecting the smaller debris in an AeroGel fish net?

Think it won't hold up to the task? Check out the photos of AeroGel. The fluffy thing can hold up a brick!

NASA is already using AeroGel in the StarDust mission to collect high-velocity particles.

Thick enough, it could be used to capture those tiny bolts and fragments they can't track by radar.

Also, one of their concerns about using lasers to zap bigger debris was the fear of generation bazillion smaller particles that couldn't be collected or tracked thereafter.

Why not create an autonomous robot that circles the globe, zap the objects it can while collecting the smaller debris in an AeroGel fish net?

Think it won't hold up to the task? Check out the photos of AeroGel. The fluffy thing can hold up a brick!

NASA is already using AeroGel in the StarDust mission to collect high-velocity particles.

Thick enough, it could be used to capture those tiny bolts and fragments they can't track by radar.

Also, one of their concerns about using lasers to zap bigger debris was the fear of generation bazillion smaller particles that couldn't be collected or tracked thereafter.

Why not create an autonomous robot that circles the globe, zap the objects it can while collecting the smaller debris in an AeroGel fish net?

Think it won't hold up to the task? Check out the photos of AeroGel. The fluffy thing can hold up a brick!

And a side order of inverse tachyon pulses?

Carbon nanotubes have become a hot item of discussion across all fields of engineering because, in part, the cylinders constructed from hexagonal links of carbon atoms are believed to be perhaps the strongest manmade material.

That should be "strongest material fullstop". The inference to natural materials can only be referring to spider silk. Spider dragline silk has a tensile strength comparable to steel, but will stretch 35% without breaking. It seems steel can achieve up to about 5 Gpa in tensile strength depending on quality, etc. Carbon nanotube fibres are expected to be in the hundreds of Gpa.

There is a cautious belief amongst materials scientists that carbon nanotubes may in fact be the strongest substance possible in terms of tensile strength.

A great overview of nanotubes as a construction material can be found in Bradley Edward's Space Elevator manuscript. See also the slashdot discussion about it.

a NASA technical report server of course!

And what makes you think the shuttle has the computing power of a P90? I find it hard to believe that NASA hasn't upgraded the computer system in the shuttle. And if they haven't, it's probably because they haven't needed to.

This is true. i seem to recall just a few years ago NASA finished upgrading the computer systems on all the shuttles. Cockpit displays are all now digital instead of analogue and i'm sure the necessairy upgrades to all the other sytems were made as well.

Here is a reference to some of the upgrades. I'm sure better information about it is out there somewhere.

Not true. While the new cockpits are the biggest and most noted upgrades, there are a ton of upgrades to everything from the main engines to the steerability of the nosewheel.

It's interesting to note that domestic television satellites didn't reach North America until 1972, 10 years after Telstar. Here's a link to a Communications Satellites Short History. From that page:

In 1965, ABC proposed a domestic satellite system to distribute television signals. The proposal sank into temporary oblivion, but in 1972 TELESAT CANADA launched the first domestic communications satellite, ANIK, to serve the vast Canadian continental area. RCA promptly leased circuits on the Canadian satellite until they could launch their own satellite. The first U.S. domestic communications satellite was Western Union's WESTAR I, launched on April 13, 1974.

You did not say whether your laptop is using chemical batteries or plutonium thermal batteries. You also did not define what you consider to be a "better" quality of a source.

The Galilean moons are large enough to be spherical and to show geological processes and to hold on to trace atmospheres. That means there is probably much more to study with them than with the smaller moons, which have little geology aside from impact cratering. This is not meant to be a value judgement, merely an unfortunate pragmatic fact.

The Space Shuttle has had to have its cockpit windows replaced because of impacts with tiny objects - such as particles of paint, which are capable of gouging visible craters in the surface.

Whilst we have only intentionally put a few thousand pieces into orbit, we have put much more debris up there. Pieces of paint from the booster, particles ejected by explosive bolts, nuts, bolts screws... Sometimes old rocket stages disintegrate or explode. A Pegasus booster exploded in 1996 putting an estimated 300 000 particles larger than 4mm into orbit, over 500 of those particles were large enough to be tracked by ground radar.

I'm not sure if Ed White's glove is still up there after he lost it on Gemini 4 :)

Some spacecraft (such as the Soviet nuclear-powered radar satellites) have ejected their coolant as a stream of droplets...

The US had a program called West Ford that ejected 400 million copper dipoles from the Midas satellites - no idea if they are up there.

The Soviets constructed anti-satellite satellites that exploded in close proximity to other spacecraft - a number of those were tested...

Fortunately most objects will either re-enter after a short period or are safely sitting in unused orbits, but a good number are in the popular orbits where they could cause havoc to a delicate mirror.

In fact some people have even gone so far as to suggest that the sheer number of things up there could cause a catastrophe... if one object hits another, it could eject more particles which impact on other objects releasing further particles in a cascade of debris that would clutter up low-orbit space and make it unusable.

Not sure if I believe them, but its a scary prospect and probably not one we should test.

Best wishes,
Mike.

Well, there's no such thing as a stable orbit for anything in our solar system, period. The Moon itself is moving away from Earth gradually due to tidal effects, and none of the planetary orbits are predictable (including Earth's) for more than 100 million years or so due to chaotic instabilities in the equations of motion when you have more than 2 bodies involved...

But for orbits in the range 300 to 1000 km or so from the Moon's surface, orbital decay due to the various effects of Earth, Sun, and gravitational anomalies becomes small enough that you can expect to stay in orbit for a year or more without any extra orbital maneuvers. This isn't actually so different from Earth, where orbits close to the surface decay quickly due to the atmosphere. See a NASA technical report on the lifetimes of close orbits for more information...

That's an interesting idea but your optimism fails to take into account some of the basic principles of optics. First, a large aperature telescope gathers more light, allowing fainter objects to be seen. A 100m telescope will gather the same light as 10,000 1m telescopes.

Having multiple smaller insturuments operating as an interferometer does increase resolution. You get the same ability to resolve detail as a telescope of an aperature equal to the distance separating the telescopes. But there are a lot of technical issues involved in interferometers as they require extremely small tolerances.

Also you discount variations in weather as a nominal problem but, in fact, this is the main hurdle to creating a GCT.

You also underestimate cost massively. Even assuming you can build a 1m telescope for $100,000. You will need 10,000 of them to equal the light gathering of a single 100m telescope. This would put the cost at $1 billion. But in all likelihood a 1m telescope will cost at least $1 million, putting the actual cost at $10 billion.

For more information on interferometers, please visit this website:
http://huey.jpl.nasa.gov/keck/index.html

I know this are going to be a quick list:

Mentalhealth.com

NASA

Violence

I don't know about you but having two separate studies, one from a "University" in Japan, and one from NASA, I am more likely to choose the side that NASA is on! ;)

It does seem strange that the Japan one says it causes ADD and the NASA one says it cures ADD! WTF?

but having something that big in space is out of the question. With a paradigm shift however, the problem is solved. Check out the DART which consists of two parabolically curved sheets (2D) instead of one large dish (3D). Because it consists of sheets you could just roll the material out of a shuttle onto a framework constructed in space. They are currently building precision small scale prototypes of this at JPL , and they are talking about making them very very big.

Because of the huge cost involved in such a project and the increasing risk of orbital debris the telescope will be sheathed in a special alloyed sleeve. The sleeve itself is so massive that it is estimated it will take 3 shuttle flights to lift its segments. Detractors of the project say that while the sleeve does provide excellent protection that fact is more than offset by decreased mobility by making the craft ungainly and impractical to manoeuvre. Another concern is that the huge size of the telescope will interfere with the viewing instrumentation on other nearby space instruments.

However project director Harold Mann responded to the criticisms by saying "Sure my SUV blocks other's view, has terrible fuel efficiency, and handles like shit, but hey if there's a collision it'll be the other guy who gets creamed, especially if it's one of those dinky Japanese models, and in America that's how we like it."

Because of the huge cost involved in such a project and the increasing risk of orbital debris the telescope will be sheathed in a special alloyed sleeve. The sleeve itself is so massive that it is estimated it will take 3 shuttle flights to lift its segments. Detractors of the project say that while the sleeve does provide excellent protection that fact is more than offset by decreased mobility by making the craft ungainly and impractical to manoeuvre. Another concern is that the huge size of the telescope will interfere with the viewing instrumentation on other nearby space instruments.

However project director Harold Mann responded to the criticisms by saying "Sure my SUV blocks other's view, has terrible fuel efficiency, and handles like shit, but hey if there's a collision it'll be the other guy who gets creamed, especially if it's one of those dinky Japanese models, and in America that's how we like it."

Notes from NASA:

What's orbiting in our near-Earth space environment?
Orbital debris in the near-Earth space environment is made up of micrometeoroids and man-made debris. The man-made debris or space junk consists mainly of fragmented rocket bodies and spacecraft parts created by 40 years of space exploration. These objects number in the millions and orbit the earth at hypervelocities averaging 10 km/s (22,000 mi/h).

From the White Sands Hypervelocity Impact Test Facility. The Orbital Debris article is the source.

So maybe I did oversimplify.

how can we stop global warming... Assume for a moment that global warming is like any force, just beacuse the change is still relatively small doesn't mean that the accelleration isn't huge. Once you want to "change" it's like stopping a car... it will take a while. A long while. If it took us 200 years to start serious warming, it may very well take us 300 years to do the cooling. And by then it may be just too late.

There are four types of people: those who are ignorant and know it; those who are knowlegable and don't; those that are knowlegable and know it; and those who are ignorant but think that they are knowlegable. You my fellow biped are in the latter category; and what a dangerous person you are beacuse of this. Why a moderator would mark you as insightful is beyond me. Spreading ignorance under the guise of wisdom is the worst of all sins.

Then you might want to put yourself in that last category, and as one of those horrible people that spread mis-information. You might find a good look at the NASA satellite data, for temperature, enlightening. And before you complain about the fact that this only goes back to the late '70s, and that the "real" picture only shows up when we look at the average temperature since the late 1800's, I would suggest looking up the Pacific Decadal Occilation, which is really where the "warming" in the past century has come from, though most envirometalist extremists conviently smooth the data over and forget to mention that this is the only real source of warming over the past 100 years. And, as a last note, the PDO has been determined to be a natural phenomena, though I am sure the next argument will be that humans are somehow changing it as well. My advice, accept it, we are not that important and don't have that large of an impact on the Earth, its just arrogance to assume that we are the cause of every little fluctuation.

When life absorbs gamma radiation, that life is generally destroyed. The harmful mutations that exposure to gamma sometimes produces are basically a mild case of destruction.

Before anyone comments on consequent high mutation rates and speculates on rapid adaptation, it's worth pointing out that increasing the mutation rate increases the organism's genetic burden, or in other words reduces the organism's survivability. High replacement rates entail a high `genetic death' rate for the species.

Life consists of highly specific, nested, complex structures. Think of a lunar rover built from Lego bricks [looks like a fabulous place of employment!]. Units like the wheels represent a unique and specific structure by themselves; the whole rover represents a structure of structures. Doing something like bashing a chord or segment out of a wheel not only impairs the wheel's function, it also impairs the entire rover's function. What you're proposing is akin to suggesting that `improving' the rover's structure can be done by subjecting it to higher than normal levels of machinegun fire.

Dwelling in low-g for an extended period of time will cause many bad side-effects too, such as decreased bone density. Senior citizens are already frail in that respect, so they might not be the best candidates...

On the other hand, there may be ways to combat this.

each solid rocket motor weighs approximately 1,100,000 pounds

And this contradicts my claim that each exausts many millions of SUV-equivalent miles in carbon dioxide how?

The shuttle puts out lots of CO2, right. What, exactly, are you smoking?

Let's actually examine this, instead of spewing random statements. We have two engine systems in your average Shuttle, the main engines and the solid rocket boosters.

Main engines burn liquid hydrogen with liquid oxygen. Result, mostly water, along with various nitrogen compounds that come from the nitrogen in the air. No carbon products because there's no carbon!

The solid rocket boosters contain ammonium perchlorate, aluminum, iron oxide, a polymer, and an epoxy curing agent. (Source: http://science.ksc.nasa.gov/shuttle/technology/sts -newsref/srb.html) First three ingredients, no carbon. The last two might have some carbon, but they're not major ingredients (14 percent total), and they're not the fuel, so they probably aren't combining with much oxygen.

Anyway, I hope these facts don't stand in your way too much.

First, the section of the flight from low earth orbit to mars most probably won't be on the same fuel as that used for launching from the ground, for the simple reason that it's not the most efficient way to do it.

Second, the most cost-effective method of hauling heavy equipment into low earth orbit from the ground is not the space shuttle. Even the ISS gets resupplies in soyuz pods.

If they launch to the ISS, then they don't always need to send a crew with it, becuase the ISS crew has a robotarm and can to spacewalks to assemble things in space.

this company already launches commercially in both ksc in florida and in baikonur in russia. With the Proton K rocket and also with the largest version of the Atlas V, they can launch over 45000 pounds into orbit, that's more than what the shuttle can, and I'm sure a protonk launch from baikonur is a lot cheaper than a shuttle launch from jfk. Maybe energia can make bigger rockets for this, but I don't speak russian to the website is all 'chinese to me'.

(of course this all assumes they're launching spaceship parts and fuel to the ISS and assemble there).

Yeah, that number raises the old bullshit flag with me as well. The cost of the Apollo budget over the years 62 - 73 was around 20 Billion in nomial dollars. Factor in inflation since then and you get something more like $40 Billion in todays dollars. Granted, there were 7 attempted moon landing during the Apollo missions, plus 4 manned test flights, plus the Apollo 1 disaster, but still... I think they'd be lucky to get to the moon and back for $20 Billion today...

To put it mildly...

In his paper, he uses the basic COCOMO model for estimating the cost. This model, quite frankly, sucks. Boehm's book even states, more or less, that the COCOMO model is only accurate to a factor of 10.

Since I no longer have the Boehm book, this quote from a google-found web page will have to do. This is a quote of a quote from Boehm's book, Software Engineering Economics:

"Basic COCOMO is good for rough order of magnitude estimates of software costs, but its accuracy is necessarily limited because of its lack of factors to account for differences in hardware constraints, personnel quality and experience, use of modern tools and techniques, and other project attributes known to have a significant influence on costs."

Basically, this means that the estimate could be anywhere from $100M->10B in true cost.

At the very least, this kid should have stated which of the model variants he was using.

Better yet, he should have subdivided the source code into multiple categories: kernel+drivers, tools, productivity software, etc. etc., and then applied the various models to them.

Just my 2 bits.

BTW, here is the google-found page which has the quote I stole. Plus, it gives a nice, albeit brief, overview of COCOMO.

-d

"Look at NASA and other scientific organisations in the USA, notice that they DO use the metric system already,and have so for a long while."

Not only is it a good idea, it's the law since 1988.

Actually, there is quite a bit left over after a supernova. Here is a VLA radio image of Cas A. If you see the area of high emission on the right edge of the expanding cloud, that is thought to be the compact object (probably neutron star) flying off from the force of the supernova.

Here's the Hubble homepage and here is the original version at few defferent sizes, formats, and borders.

Here is what the Earth would look like next to one of these puppies, probably would destroy all life here in the blink of an eye.