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Comment Re:Perhaps a better method... (Score 1) 1001

As far as I can tell, this code is syntactically correct (if executed by a Perl interpreter).

Unless something goes terribly wrong with Perl, the code behavior is pretty well defined. It shall output the following 2 lines:

> This is the header of the output
> where are the entries?

So the only sensible answer to the question"why doesn't this work" is "it works"

Comment A few numbers (Score 3, Informative) 642

The Moon Escape velocity is 2.38 km/s while on Earth it is 11.186 km/s.

Since energy is proportional to the square of the speed (E=1/2*m*v^2) we can conclude that it is (11.186/ 2.38)^2 = 2 time easier to reach free space from the Moon than from Earth.

However, even if a rock is launched from the Moon at 2.38 km/s, it still inherits the inertia of the Moon. Simply speaking, the rock would not fall to Earth. It would be in an orbit similar to the Moon orbit.

The orbital speed of the Moon is about 1km/s so the rock must be given that additional acceleration to cancel its orbital speed.

At that point, the rock is immobile (from the Earth point of view) and it will start falling toward Earth because of ... gravity.

When it reaches Earth, its speed will be equal to the Earth Escape velocity (a bit less in fact since the rock did not start falling from an infinite distance) so 11.186 km/s.

The kinetic energy is given by the formula 1/2 * m * V^2 so for 1kg the kinetic energy at 11km/s is 1/2 * 1 * 11000^2 = 60 * 10^6 Joules

As a comparison, 1kg of TNT provides 4 * 10^6 Joules so each kg of moon rock would be equivalent to approximatively 15kg of TNT

The Hiroshima bomb was 15 kilotons of TNT = 15 * 10^6 Kg so a similar effect would require a 1000 tons of Moon rock and the ability to accelerate that rock to a speed of 2.38+1 = 3.38 km/s.


Comment Re:Moon dust depth (Score 1) 140

The 1mm/1000 years figure is flawed. It is based on an incorrect value of 14 millions tons of dust per year computed in the early 60th. More recent figures are 100 to 1000 time smaller.

Even creationists websites do not use anymore moon dust as an argument. For instance look at the last paragraph in the Conclusion section of

"Calculations show that the amount of meteoritic dust in the surface dust layer, and that which trace element analyses have shown to be in the regolith, is consistent with the current meteoritic dust influx rate operating over the evolutionists’ timescale. While there are some unresolved problems with the evolutionists’ case, the moon dust argument, using uniformitarian assumptions to argue against an old age for the moon and the solar system, should for the present not be used by creationists."

Comment Re:So many theories... so many on the payroll list (Score 1) 90

I could almost agree with you except that my critic was not against religion as a whole but against a literal interpretation of religious texts.

The issue is not science vs religion but reality vs blind faith in an absolute truth.

More generally, the same problem is found in non-religious contexts such as flat earth and other conspiracy theories where people will first assert a truth and then will ignore any evidence against it.

Comment Re:So many theories... so many on the payroll list (Score 3, Insightful) 90

What you are suffering from is called a displacement.
More precisely you appear to assume that scientists, like the creation myth in your favorite holy book, are claiming an absolute trust.

That does not work like that in the real world. Scientists create models and then try to invalidate them by comparing to reality.

Eventually all models become invalidated and are replaced by newer models that fit better with reality.

No sane scientist will ever claim that a specific model is absolutely true. That is why the article is full of "may" and "suggests". Same for the page that describes the single large collision model.

The only thing that is correct in your post is that from the 5 scientists involved in your short story, the last one is probably the one that merits the most to be fired.

Why? Because scientists #1 and #3 are both proposing a model. Scientists #2 and #4 are defending those models. The only one that is not contributing in any useful way is scientist #5.

United States

House Committee Urges Congress To Pass Stingray Surveillance Legislation ( 25

A bipartisan House Oversight and Government Reform Committee report released today urges Congress to pass legislation to regulate cell-site simulation surveillance devices like the Stingray. From a report: The devices, used by local and federal law enforcement agencies around the country, have been controversial, both for their power to track mobile devices and the secrecy often accompanying their use. As the report notes, the devices are still often used by local law enforcement agencies without warrants, instead relying on various lower standards of evidence. The committee's investigation, which last year prompted the Justice Department and Department of Homeland Security to change their policies on when to require a warrant before using the devices, found that the Justice Department uses 310 of the devices and spent $71 million on them between fiscal years 2010 and 2014. Homeland Security has 124 devices and spent $24 million in the same period. [...] The committee recommends that agencies become more "candid" about the devices, and urges states to pass legislation that would "require, with limited exceptions, issuance of a probable cause based warrant prior to law enforcement's use of these devices."

Comment Re:We're so screwed (Score 1) 293

At sea level and at 15 C air has a density of approximately 1.225 kg/m3 = 0.001225 g/cm3 .00198 g/cm3 would imply a CO2 concentration of 1600% dumbass. At 400ppm a proper value is more like 0.00000049 g/cm3 so 4000 time smaller than your claim.

That does not change anything for my claims though.

Look! I am feeding the troll with ammos. Can't wait for the next shitty argument he will pull out of his ass.

Comment Re:We're so screwed (Score 1) 293

I just figured out that I forgot to take into account that CO2 is heavier than O2 and N2.
The molar mass of air is about 29 g/mole while that of CO2 is 44 g/mole.

In practice, that means that my hypothetical sheet of solid CO2 would be 44/29 = 1.5 times heavier than previously computed and, at 400ppm, its thickness would be 5mm instead of 3.3mm.

Comment Re:Didn't we see it coming? (Score 1) 293

I assume that those 20X are referring to the sentence in the early years of this century, concentrations of methane rose by only about 0.5ppb each year, compared with 10ppb in 2014 and 2015"

As usual the article is misleading.

Look at the data in

There was no noticeable increases during the period 2000-2010. There was some small fluctuations and the methane concentration was even decreasing for a few yers. Computing the ratio of two values only make sense if both values are large.

Here some of the values are even negative. Can we say that between 2001 and 2015, there was an acceleration of 9.98/-0.65 = -15.3X ?
If one year, the increase was exactly 0 then all other years would show an infinitely acceleration.
That does not make sense

The only important value is the long term trend. Looking at the graph, the increase was approximatively 210ppb during the last 30 years so an average of 7-8ppb per year.

Increases of 12.61 ppb and 9.98 ppb measured in 2014 and 2015 are above average but not by much. The increase was even higher during the late 80th.

Comment Re:We're so screwed (Score 5, Insightful) 293

No. Neither Nitrogen (N2) nor Oxygen (O2) are greenhouse gases and they compose most of the atmosphere.

Ozone (O3) is a form of oxygen that is considered a greenhouse gas but its concentration is small.

The following pages summarize quite well the situation:

More generally, the argument "it is only a small percentage of the whole atmosphere" is invalid. What is important is not the percentage of the various gases but their amount and their efficiency for trapping heat.

Also, people tend to underestimate the amounts of matter involved when talking about ppm or ppb. In we find that "A column of air one square centimeter [cm2] (0.16 sq in) in cross-section ... has a mass of about 1.03 kilograms (2.3 lb)"

So the solar radiation that hits each cm2 of the earth surface has to go through about 1kg of air = 1000g.

The CO2 concentration is 400ppm so the solar radiation passes through 1000g * 400/1000000 = 0.4g of CO2 per cm2

Polycarbonate sheets used in most garden greenhouses has a density of 1.2g/cm3.

If atmospheric CO2 was compressed to that same density to form a hypothetical sheet of solid CO2 then its thickness would be 0.4/1.2 = 0.33 cm = 3.3mm

This is very comparable to the thickness of typical a polycarbonate sheet (3 to 6mm) so saying that 400ppm of CO2 cannot have any noticeable effects seems as stupid as saying that greenhouses are ineffective.


Comment Re:"it was used for children's writing exercises" (Score 4, Insightful) 235

More generally, "name calling" should be the expected behavior when asking almost any complex question to any large group of persons.

However, in that specific case, Richard Dawkins has the expected default position of any atheist (including me): The existence of an invisible unproven magic being cannot be the answer to any complex phenomena observed in the real world (in that case, that would be the origin of life). That position implies that there are things that we cannot explain with our current understanding of nature (you know, that thing called science).

Improving science by looking for more clues in the real world is the right way to handle those mysteries. Claiming "Magic", "God", "Taboo" or "Holy Book" is not.

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