No worries, I just remember getting a 'C' for writing an essay only mentioning a biogenic source, with a comment to go check the literature. I learned a lesson that day:)
If you're interested, Wired wrote up about Gold's theory a while back.
There are hundreds of wells drilled more than 5 km deep, below the levels of prehistoric plants (what is called "basement rock"), and they are still productive.
Basement usually refers to ancient metamorphic or igneous rocks. AFAIK there are no productive wells in such areas.
Sedimentary rocks can be pushed down beyond 5km in so-called downwarps. In fact they are almost essential since the oil formation process requires the source rocks to enter the so-called 'oil window'. As rocks get buried, the temperature rises, theories suggest that between 80 and 140 Celsius is optimum for oil production - going up to about 200 with decreasing yield of oil (but increasing natural gas production).
The average geothermal gradient is around 25C per km, meaning that the oil window sits comfortably in the 5 to 6 km depth. In many places (particularly those where mountain forming is going on), the geothermal gradient may be as low as 15C per km) - meaning that oil production can go on at even deeper levels in the Crust.
5km wells are highly unusual simply because oil tends to migrate upwards into traps much closer to the surface.
There is no shortage of clear proof that this is where the oil comes from. Coal contains clearly fossilised plant material.. oil and coal and natural gas are often all found together.
Actually there is some evidence for a non-biogenic source for some oil reserves. It came as a surprise to me as well when I did my geology degree.
Thomas Gold (most famous for his Steady-State Theory of the Universe) postulated that oil might be formed from organic compounds deep in the Mantle which migrate up to the surface. IIRC he persuaded the Swedes to sink a test well into ancient hard shield rocks (where there should be no signs of hydrocarbons) and indeed traces of such compounds were recovered. Now I don't know whether they excluded the possibility that they were products of the lubricating mud used to drill the well or if they were younger oil seeping into the basement rocks from a distant reservoir.
However, the vast majority of oil reserves are clearly from fossilised plants. The breakdown products of porphyrins (the complex organo metal compounds such as chlorophyll) can be extracted from most crudes.
Finally, oil, coal and natural gas may be found close to one another, but are usually not. For instance, the mainland of the UK has enormous coal reserves, but only one productive oil field and no on-shore gas. British oil probably originates in the Kimmeridge Clay - an organic rich clay that was formed in the late Jurassic. Conversely, the Middle East almost entirely lacks coal, but holds 60% of the World's petroleum reserves. The closest association is usually natural gas and oil - where it has been driven off from oil reservoirs that have been heated.
In the Southern North Sea much of the natural gas probably came from the underlying Coal Measures which have been deeply buried and exposed to intense heat.
Our economic infrastructure is dependent on *fuel* consumption, it doesn't much matter what fuel that happens to be.
Oil won't be replaced by some magical happy juice that nobody has to pay for, it'll be replaced by some other fuel commodity that will perform the same function both physically and economically.
It will be replaced first of all by synthetic fuels made from other hydrocarbons. The technology for making such fuels dates all the way back to the 1920s.
The Nazis ran most of their aviation fleet on synthetic fuels since Germany lacked petroleum reserves, but it did have a lot of lousy coal. In addition synthetic gasoline does not need added lead and has very high octane numbers (unlike straight run gasoline which needs to be catalytically reformed to offer the same performance).
Apartheid South Africa did exactly the same for the same reasons - no natural oil reserves.
The main method of making such fuels is the Fischer Tropsch Process, discovered in Germany shortly after World War I. Essentially a fossil fuel (coal, oil, tar or gas) is reacted with superheated steam to produce a mixture of carbon monoxide and hydrogen (a mixture known as water gas). These are then reacted in the presence of an iron or cobalt catalyst to produce hydrocarbons and water. A lot of work has gone into manufacturing superior catalysts so as to control the exact types of hydrocarbon coming out of the end of the plant.
Only this week, Royal Dutch Shell announced a joint venture with the government of Qatar for a gas to liquid (GTL) plant. Qatar has enormous gas reserves, but no nearby market. Shell is going to use the Fischer Tropsch process to manufacture synthetic diesel.
Sounds too good to be true? Yep, its a disgustingly un-environmental process that consumes ENORMOUS amounts of water, and emits vast quantities of carbon dioxide and polluted water. Synthetic fuels will not save us from the greenhouse effect.
Biofuel? Oh god here we go again. Unless you grow these plants WITHOUT the use of artificial fertiliser they are going to be consuming more fossil fuel energy than you get out the other end. Fertilisers are made from ammonia - which is made from natural gas.
And hydrogen. Yes you can get it from electrolysis (but the process is not the most efficient method of making it - thermal cracking of water in the presence of iodine has higher efficiencies), but nowadays the vast majority of hydrogen production is from the catalytic decomposition of methane (natural gas) or the reforming of hydrocarbons to manufacture alkenes.
So in the short, medium and long term we're still going to be guzzling those hydrocarbons.
It's also not just a theory. I believe the Brits lost an oil rig this way a couple years ago.
It has been suspected that the wreck of a trawler found in an area called 'The Witches Hole' NE of Aberdeen might be related to this event. The wreck is apparently sitting upright, nets and deck equipment intact in the middle of a crater. AFAIK no one has identified the ship as yet, but it looks like a late 19th or early 20th Century vessel.
But no rigs.
IIRC this theory was featured in an episode of the Channel 4 series 'Equinox' at least a decade ago. They spent 50 minutes debunking the Bermuda Triangle - it doesn't exist, and then 10 minutes talking about gas blowouts sinking the ships that didn't actually disappear.
You talk about Norway's population density being less than the US. In many places, I have no doubt that's the case. However, despite the low population density, Norway is still only slightly larger than New Mexico. I bet it'd be pretty easy for AT&T or Sprint to hook up New Mexico with a bitchin' wireless setup, and have EVERYONE be covered.
Yeah, but if you flattened Norway out it would be HUGE!:)
In its later revisions it had a longer range than Concorde and was more fuel economic.
It had a longer range only if it did not go supersonic since it needed afterburners for supersonic cruise. There were several unresolved problems with the Tu144 including inefficient engines and a double-delta wing which was not as good as the ogival wing on Concorde.
The Tu144 was a Kruschev kludge to beat Concorde. The original design with four engines under the belly was the one that made all the early records, but it was not the one that eventually entered service nearly five years later.
The Tu144 also benefitted from enormous amounts of espionage against Britain and France. Amusingly, the French got their own back when they found the KGB was sniffing around Michelin looking for the formula of the rubber used to construct the high-speed tyres of Concorde. French intelligence leaked the 'formula' to the Soviets. What they actually gave them was a rubber with the composition and properties of bubblegum - so imagine if you will a Soviet SST firmly stuck to the runway with a lot of engineers wondering what they had forgotten.
However, for various reasons, the Soviets never really used the Tupolev 144
The terrible crash at Paris was one and there were reports of another crash inside the Soviet Union. Since the plane could not fly Moscow -> New York without refuelling, the Atlantic route was out of the question. It was used briefly for an Aeroflot service between Moscow and the Kazakh capital.
Its interesting to also note that NASA picked this aircraft over Concorde for various tests done in the late '90s.
An easy explanation, all of the Concordes were needed by the British and French. The Tu144 was rusting away in the scrapyeard. The Russians needed cash. NASA had cash.
Basically Concorde was a supersonic bomber plane modified to carry passengers.
Uh no, Concorde was designed from the ground up to be a civilian airliner.
Had fuel remained cheap and air travel remained a premium-priced market, Concorde would have made business sense, but since it didn't and it didn't, Concorde was a financial catastrophe.
The satellite launch capability developed by Britain and then dropped. (The Black Knight series of rockets.)
And since we're on the great British bad decisions for aviation - the TSR2. Would have wiped the floor with anything else in the skies, cancelled in a crappy deal to buy inferior F111s (which we never bought). Oh and it looks beautiful.
I grew up in Cornwall under the flight path for the Air France Concorde, and we used to get the sonic boom fairly regularly. (Although Concorde wasn't meant to be supersonic over land, the Air France crews would sometimes delay hitting the brakes until the last minute).
It was a Ba-dooom noise, two thumps - particularly noticeable in cold clear weather; perhaps as loud as distant thunder. Occasionally a window would rattle, but scared animals 0, broken glass - zip.
No, the taxpayer subsidized Concorde, to the tune of 3,300 per passenger per flight.
Sorry those were developmental costs which have long been written off by the British and French governments. At the same time the two Concorde fleets were sold to the national airlines for a tiny sum.
The British Airways Concorde then went on to fly at an operational profit, (at least until the Paris crash). I believe the French Concordes were never profitable, simply because less air traffic is routed through Charles de Gaulle than Heathrow.
And let's face it, if you were back in the 1960s and planning a plane for the 1970s, what would you have thought was the most likely future: faster or just bigger?
Britain and France gambled on Concorde and lost, Boeing were the big winners, but let's remember that Boeing was determined to get into SST throughout the 1960s - it was foresighted enough to also work on the 747 concept.
Theoretically, you could have the nationwide election results within 2 hours. 1 Hour for each local volunteer to count the 1,000 votes allocated to them, 45 minutes for the state centers to add up the phone calls, 15 minutes for the national headquarters to do the grand totals.
In the UK that would not be permitted. All votes must be counted in the presence of officials (including the candidate) from each party.
Hence as soon as the ballots close (usually at 22:00), ballot boxes for elections to Parliament are sent to a central point in each seat where they will be counted. For European Elections, the country is divided into a number of regions, each region has a number of local centres where ballot papers are collected and counted.
We still get almost all votes counted within seven hours, the fastest count for a seat was something like 45 minutes after polls closed.
A few seats don't start their counts until the following day, whilst the proportional representation system used in Northern Ireland means that results from that region only crawl in after nearly a day.
A properly programmed touch-screen machine on which a voter can verify the proper vote was recorded has an error rate of 0.
The emphasis there being 'properly programmed' - how does Joe Public know that the machine is recording their vote correctly.
In the UK we can count 95% of some 26 million votes in less than seven hours. The rest are delayed slightly by things like votes from islands needing to be flown to regional counting centre and the never-ending fun of Northern Ireland's voting system. The votes are counted in front of party representatives where they can be scrutinised - almost no votes in the UK are contested by the losing party. I'm not entirely sure what the advantage of the machine is.
Besides, any system that deprives us of Election Night Specials with Peter Snow and his latest SGI ubergraphic 'just a bit of fun' escapades is a definite no-no. Watching politicians squirm for a few hours is great sport. Long may it continue!
Oh, like Rome? When Rome fell, so did the world. It may be harder for us to live with it, but it will also be hard for you. None of our money being sent to your countries anymore.
More the other way round, its OUR money plugging your current account deficit to the tune of $2 billion a day. (And getting bigger).
Make no mistake, the Chinese space program is purely a military operation and is not civilian like those in the United States and Europe. If China achieves space superiority, you can kiss all your western freedoms and comforts good bye.
They were believed to be at the time. However, such wars are in no way condoned by any of the writings in the New Testament. I doubt Jesus would have approved.
Christianity has the concept of 'Just War' - where battles are fought against a greater evil.
Unfortunately the exact definition of 'just' is often left up to the politicians who launched the war in the first place.
Nah, what they _need_ are good, attentive teachers, instead of computers to replace teaching. Plenty of very, very, very smart and successful people made it in society without growing up with computers.
Amen!
How many good teachers and classroom assistants could you get for $39 million a year? How many libraries could be fitted out with up-to-date books? How many people could be invited into the schools to inspire the children?
Yes, they'll need IT skills in time, but let's get a generation of schoolkids who know how to learn and who want to learn first.
The things you need in schools are good teachers with good resources. Sadly, plenty of places in the US (and the UK where we have much the same fixation of technological 'solutions') lack even those. Neither Dell nor Apple can substitute for good teaching.
A friend just got a new Lexmark printer as part of a computer bundle and they didn't even bundle a black cartridge! Just one of those teeny-weeny colour cartridges which was used to print b/w and colour.
He phoned Lexmark to ask if there had been a mistake, but oh-no, they NEVER throw in a black cartridge - which must be unique, HP and Canon always throw in a pair of cartridges with their printers.
So that was another 20 quid - thank-you very much.
So not only are Lexmarks expensive to run, but they are expensive to buy.
Perhaps one of the most fascinating things about the Meteor Crater(TM) in Arizona, is that about 50 miles to the North, on Hopi land, there's a site that was the muddy bank of a river, where dinosaurs had walked and left footprints. The heat from the meteor impact baked the mud, and preserved these dinosaur footprints, some eggs, and other items of interest. I
One slight problem there. Meteor Crater dates to around 50 000 years ago. The dinosaurs went to their maker around 65 million years ago.
Though I will agree, Meteor Crater is an awe-inspiring place.
Reminds me of an article in Nature (Wood, W. T., et al. Nature 420, 656-660 (2002)) that discussed how methane in seafloor deposits is released to the oceans. One of the points discussed was that as seawater temperature rises, the base of gas hydrate stability rises. What this means is that some of the methane trapped under the seafloor in solid methane hydrate turns instead into methane gas due to the increase in temperature. This release of gas in turn will increase the pressure near the seafloor, and if close enough to the surface, or near a fault that allows a gas chimney to form, it can be released to the ocean (perhaps like a valve until the pressure subsided). Obviously this would be amplifying if it occured on a large scale since methane is a powerful greenhouse gas.
True, but analysis of oxygen isotopes in carbonate shells (the ratio of O16 to O18 is extremely temperature sensitive) shows that Mesozoic ocean temperatures were much higher than today (deep ocean temperature of around 14 Celsius compared to near zero today). The oceans were simply too warm for gas hydrates to form on the ocean floors.
They couldn't have contributed to any warming that drove extinction.
We accually move back and forth from the top of the dash to the bottom of the dash. Comprende? So we're now moving into the more dense part of the disk, so we'll see more asteroids. Coincedence that the last time we were here the dinosaurs mysteriously vanished? I think not.
Why will we see more asteroids? Every single asteroid and comet that has had its orbit traced orbits firmly within the Solar System. No object has ever been seen entering the Solar System on a hyperbolic trajectory (they are occasionally ejected on such a trajectory after encountering Jupiter).
The Galactic Disk is a relatively diffuse entity - it IS massive - but it is also huge. Even at its densest, the Sun will more than likely pass many light years from any other stars.
If the passage of the Sun through the Disk was associated with mass extinctions, then you'd expect to see a periodicity in extinctions as the Sun bobs above and below the Galactic Equator. No such periodicity has been found.
I ask one question, could this rock not have come from the same source as the billions of rocks that litter the martian surface? I.E. somewhere other than Mars.
Two reasons for suspecting they originated on Mars:
Martian meteorites come in a range of ages - some as young as a billion years old. By comparison, most meteorites hang out around the 4.6 billion years old mark - the point when small planetary bodies were forming in the Solar System.
For rocks to be much younger than 4.6 billion they have to come from a body that was evolving - that was hot, partially molten and volcanically active. Such a body would have to be big - a planet. Mars is the most obvious candidate, it shows clear signs of tectonism until relatively recently - new rock was being formed on Mars within the last billion years.
The second reason for suspecting these are Martian rocks is so clever it borders on magical. Some meteorites have been analysed in the lab. They contain vesicles - tiny bubbles of gas trapped in the molten rock. When the rock cooled and froze, the gas was trapped.
When these bubbles are cracked open, the gas inside can be analysed. The ratios of the inert gases (gases such as neon, argon and krypton) precisely match the ratios in the Martian atmosphere measured by American and Soviet probes.
I've no idea if the Egyptian dog-killer has been analysed though.
Slashdot Mirror
If you're interested, Wired wrote up about Gold's theory a while back.
Best wishes,
Mike.
Basement usually refers to ancient metamorphic or igneous rocks. AFAIK there are no productive wells in such areas.
Sedimentary rocks can be pushed down beyond 5km in so-called downwarps. In fact they are almost essential since the oil formation process requires the source rocks to enter the so-called 'oil window'. As rocks get buried, the temperature rises, theories suggest that between 80 and 140 Celsius is optimum for oil production - going up to about 200 with decreasing yield of oil (but increasing natural gas production).
The average geothermal gradient is around 25C per km, meaning that the oil window sits comfortably in the 5 to 6 km depth. In many places (particularly those where mountain forming is going on), the geothermal gradient may be as low as 15C per km) - meaning that oil production can go on at even deeper levels in the Crust.
5km wells are highly unusual simply because oil tends to migrate upwards into traps much closer to the surface.
Best wishes,
Mike.
Actually there is some evidence for a non-biogenic source for some oil reserves. It came as a surprise to me as well when I did my geology degree.
Thomas Gold (most famous for his Steady-State Theory of the Universe) postulated that oil might be formed from organic compounds deep in the Mantle which migrate up to the surface. IIRC he persuaded the Swedes to sink a test well into ancient hard shield rocks (where there should be no signs of hydrocarbons) and indeed traces of such compounds were recovered. Now I don't know whether they excluded the possibility that they were products of the lubricating mud used to drill the well or if they were younger oil seeping into the basement rocks from a distant reservoir.
However, the vast majority of oil reserves are clearly from fossilised plants. The breakdown products of porphyrins (the complex organo metal compounds such as chlorophyll) can be extracted from most crudes.
Finally, oil, coal and natural gas may be found close to one another, but are usually not. For instance, the mainland of the UK has enormous coal reserves, but only one productive oil field and no on-shore gas. British oil probably originates in the Kimmeridge Clay - an organic rich clay that was formed in the late Jurassic. Conversely, the Middle East almost entirely lacks coal, but holds 60% of the World's petroleum reserves. The closest association is usually natural gas and oil - where it has been driven off from oil reservoirs that have been heated.
In the Southern North Sea much of the natural gas probably came from the underlying Coal Measures which have been deeply buried and exposed to intense heat.
Best wishes,
Mike.
Oil won't be replaced by some magical happy juice that nobody has to pay for, it'll be replaced by some other fuel commodity that will perform the same function both physically and economically.
It will be replaced first of all by synthetic fuels made from other hydrocarbons. The technology for making such fuels dates all the way back to the 1920s.
The Nazis ran most of their aviation fleet on synthetic fuels since Germany lacked petroleum reserves, but it did have a lot of lousy coal. In addition synthetic gasoline does not need added lead and has very high octane numbers (unlike straight run gasoline which needs to be catalytically reformed to offer the same performance).
Apartheid South Africa did exactly the same for the same reasons - no natural oil reserves.
The main method of making such fuels is the Fischer Tropsch Process, discovered in Germany shortly after World War I. Essentially a fossil fuel (coal, oil, tar or gas) is reacted with superheated steam to produce a mixture of carbon monoxide and hydrogen (a mixture known as water gas). These are then reacted in the presence of an iron or cobalt catalyst to produce hydrocarbons and water. A lot of work has gone into manufacturing superior catalysts so as to control the exact types of hydrocarbon coming out of the end of the plant.
Only this week, Royal Dutch Shell announced a joint venture with the government of Qatar for a gas to liquid (GTL) plant. Qatar has enormous gas reserves, but no nearby market. Shell is going to use the Fischer Tropsch process to manufacture synthetic diesel.
Sounds too good to be true? Yep, its a disgustingly un-environmental process that consumes ENORMOUS amounts of water, and emits vast quantities of carbon dioxide and polluted water. Synthetic fuels will not save us from the greenhouse effect.
Biofuel? Oh god here we go again. Unless you grow these plants WITHOUT the use of artificial fertiliser they are going to be consuming more fossil fuel energy than you get out the other end. Fertilisers are made from ammonia - which is made from natural gas.
And hydrogen. Yes you can get it from electrolysis (but the process is not the most efficient method of making it - thermal cracking of water in the presence of iodine has higher efficiencies), but nowadays the vast majority of hydrogen production is from the catalytic decomposition of methane (natural gas) or the reforming of hydrocarbons to manufacture alkenes.
So in the short, medium and long term we're still going to be guzzling those hydrocarbons.
Best wishes,
Mike.
It has been suspected that the wreck of a trawler found in an area called 'The Witches Hole' NE of Aberdeen might be related to this event. The wreck is apparently sitting upright, nets and deck equipment intact in the middle of a crater. AFAIK no one has identified the ship as yet, but it looks like a late 19th or early 20th Century vessel.
But no rigs.
IIRC this theory was featured in an episode of the Channel 4 series 'Equinox' at least a decade ago. They spent 50 minutes debunking the Bermuda Triangle - it doesn't exist, and then 10 minutes talking about gas blowouts sinking the ships that didn't actually disappear.
I think that's known as 'covering your bases'.
Best wishes,
Mike.
Yeah, but if you flattened Norway out it would be HUGE! :)
Best wishes,
Mike.
It had a longer range only if it did not go supersonic since it needed afterburners for supersonic cruise. There were several unresolved problems with the Tu144 including inefficient engines and a double-delta wing which was not as good as the ogival wing on Concorde.
The Tu144 was a Kruschev kludge to beat Concorde. The original design with four engines under the belly was the one that made all the early records, but it was not the one that eventually entered service nearly five years later.
The Tu144 also benefitted from enormous amounts of espionage against Britain and France. Amusingly, the French got their own back when they found the KGB was sniffing around Michelin looking for the formula of the rubber used to construct the high-speed tyres of Concorde. French intelligence leaked the 'formula' to the Soviets. What they actually gave them was a rubber with the composition and properties of bubblegum - so imagine if you will a Soviet SST firmly stuck to the runway with a lot of engineers wondering what they had forgotten.
However, for various reasons, the Soviets never really used the Tupolev 144
The terrible crash at Paris was one and there were reports of another crash inside the Soviet Union. Since the plane could not fly Moscow -> New York without refuelling, the Atlantic route was out of the question. It was used briefly for an Aeroflot service between Moscow and the Kazakh capital.
Its interesting to also note that NASA picked this aircraft over Concorde for various tests done in the late '90s.
An easy explanation, all of the Concordes were needed by the British and French. The Tu144 was rusting away in the scrapyeard. The Russians needed cash. NASA had cash.
Best wishes,
Mike.
Uh no, Concorde was designed from the ground up to be a civilian airliner.
Had fuel remained cheap and air travel remained a premium-priced market, Concorde would have made business sense, but since it didn't and it didn't, Concorde was a financial catastrophe.
Best wishes,
Mike.
And since we're on the great British bad decisions for aviation - the TSR2. Would have wiped the floor with anything else in the skies, cancelled in a crappy deal to buy inferior F111s (which we never bought). Oh and it looks beautiful.
Best wishes,
Mike.
It was a Ba-dooom noise, two thumps - particularly noticeable in cold clear weather; perhaps as loud as distant thunder. Occasionally a window would rattle, but scared animals 0, broken glass - zip.
Best wishes,
Mike.
Sorry those were developmental costs which have long been written off by the British and French governments. At the same time the two Concorde fleets were sold to the national airlines for a tiny sum.
The British Airways Concorde then went on to fly at an operational profit, (at least until the Paris crash). I believe the French Concordes were never profitable, simply because less air traffic is routed through Charles de Gaulle than Heathrow.
And let's face it, if you were back in the 1960s and planning a plane for the 1970s, what would you have thought was the most likely future: faster or just bigger?
Britain and France gambled on Concorde and lost, Boeing were the big winners, but let's remember that Boeing was determined to get into SST throughout the 1960s - it was foresighted enough to also work on the 747 concept.
Eeee when I was kid we used to fly supersonic...
sigh...
Best wishes,
Mike.
In the UK that would not be permitted. All votes must be counted in the presence of officials (including the candidate) from each party.
Hence as soon as the ballots close (usually at 22:00), ballot boxes for elections to Parliament are sent to a central point in each seat where they will be counted. For European Elections, the country is divided into a number of regions, each region has a number of local centres where ballot papers are collected and counted.
We still get almost all votes counted within seven hours, the fastest count for a seat was something like 45 minutes after polls closed.
A few seats don't start their counts until the following day, whilst the proportional representation system used in Northern Ireland means that results from that region only crawl in after nearly a day.
Best wishes,
Mike.
The emphasis there being 'properly programmed' - how does Joe Public know that the machine is recording their vote correctly.
In the UK we can count 95% of some 26 million votes in less than seven hours. The rest are delayed slightly by things like votes from islands needing to be flown to regional counting centre and the never-ending fun of Northern Ireland's voting system. The votes are counted in front of party representatives where they can be scrutinised - almost no votes in the UK are contested by the losing party. I'm not entirely sure what the advantage of the machine is.
Besides, any system that deprives us of Election Night Specials with Peter Snow and his latest SGI ubergraphic 'just a bit of fun' escapades is a definite no-no. Watching politicians squirm for a few hours is great sport. Long may it continue!
Best wishes,
Mike.
More the other way round, its OUR money plugging your current account deficit to the tune of $2 billion a day. (And getting bigger).
Best wishes,
Mike.
And the $8.5 billion budgeted for US military space programs is for what exactly? Buzz Lightyear toys?
That's more than four times the entire Chinese space budget.
Get real, if there is one country hell bent on the militarisation of space, it's the United States.
Best wishes,
Mike.
Christianity has the concept of 'Just War' - where battles are fought against a greater evil.
Unfortunately the exact definition of 'just' is often left up to the politicians who launched the war in the first place.
Best wishes,
Mike.
Amen!
How many good teachers and classroom assistants could you get for $39 million a year? How many libraries could be fitted out with up-to-date books? How many people could be invited into the schools to inspire the children?
Yes, they'll need IT skills in time, but let's get a generation of schoolkids who know how to learn and who want to learn first.
The things you need in schools are good teachers with good resources. Sadly, plenty of places in the US (and the UK where we have much the same fixation of technological 'solutions') lack even those. Neither Dell nor Apple can substitute for good teaching.
Best wishes,
Mike.
He phoned Lexmark to ask if there had been a mistake, but oh-no, they NEVER throw in a black cartridge - which must be unique, HP and Canon always throw in a pair of cartridges with their printers.
So that was another 20 quid - thank-you very much.
So not only are Lexmarks expensive to run, but they are expensive to buy.
Another reason to avoid them.
Best wishes,
Mike.
Awww... I care!
Best wishes, Mike.
One slight problem there. Meteor Crater dates to around 50 000 years ago. The dinosaurs went to their maker around 65 million years ago.
Though I will agree, Meteor Crater is an awe-inspiring place.
Best wishes,
Mike.
True, but analysis of oxygen isotopes in carbonate shells (the ratio of O16 to O18 is extremely temperature sensitive) shows that Mesozoic ocean temperatures were much higher than today (deep ocean temperature of around 14 Celsius compared to near zero today). The oceans were simply too warm for gas hydrates to form on the ocean floors.
They couldn't have contributed to any warming that drove extinction.
Best wishes,
Mike.
Why will we see more asteroids? Every single asteroid and comet that has had its orbit traced orbits firmly within the Solar System. No object has ever been seen entering the Solar System on a hyperbolic trajectory (they are occasionally ejected on such a trajectory after encountering Jupiter).
The Galactic Disk is a relatively diffuse entity - it IS massive - but it is also huge. Even at its densest, the Sun will more than likely pass many light years from any other stars.
If the passage of the Sun through the Disk was associated with mass extinctions, then you'd expect to see a periodicity in extinctions as the Sun bobs above and below the Galactic Equator. No such periodicity has been found.
Best wishes,
Mike.
Two reasons for suspecting they originated on Mars:
Martian meteorites come in a range of ages - some as young as a billion years old. By comparison, most meteorites hang out around the 4.6 billion years old mark - the point when small planetary bodies were forming in the Solar System.
For rocks to be much younger than 4.6 billion they have to come from a body that was evolving - that was hot, partially molten and volcanically active. Such a body would have to be big - a planet. Mars is the most obvious candidate, it shows clear signs of tectonism until relatively recently - new rock was being formed on Mars within the last billion years.
The second reason for suspecting these are Martian rocks is so clever it borders on magical. Some meteorites have been analysed in the lab. They contain vesicles - tiny bubbles of gas trapped in the molten rock. When the rock cooled and froze, the gas was trapped.
When these bubbles are cracked open, the gas inside can be analysed. The ratios of the inert gases (gases such as neon, argon and krypton) precisely match the ratios in the Martian atmosphere measured by American and Soviet probes.
I've no idea if the Egyptian dog-killer has been analysed though.
Best wishes,
Mike.
They could even claim it was 'field testing'.
Best wishes,
Mike.
Best wishes,
Mike.