Elements of Periodic table: 3) Gold

it is probably one of the best known metals in the world and even throughout the history. Humankind knows it for a long time. It is precious metal with amazing properties from conductivity to ductility. It does not react so much which means you can actually eat it pretty easily!

Right, we are talking about gold, or aurum.
There is really lot about this element so I will start with its chemical properties and where you can find it.


Gold (Au) is amazing because it does not react much. It does not react with oxygen so you can easily have it in open place (while silver does react with oxygen), not only that but gold does not react with the strongest an-organic acids like hydrochloric acid (HCl) so only thing in which you can dissolve it is in aqua regia. 
On the left you can see aqua regia with piece of platinum which is very resistant too.

Once in Denmark during WW2 one chemist had two Nobel medals for some people. Those medals are made of gold and since Denmark was going to be captured by Nazis he did not want them to get those medals. He took them and placed them in aqua regia.
After the world he returned and the solution was still there so he extracted it and made new medals.

On the next picture you can see thin plate of gold. Gold is so ductile that one gram can be spread on 1 square meter. This picture is from Japan Toi museum.

This is very useful since gold is not very cheap but when you use only one gram for such a large area it gets to whole new level!

There is only one stable isotope of gold which is the one we are mining and using. There were found many others but all of them decay in matter of weeks, days or even couple of microseconds (actually some radioactive isotopes are used for curing cancer).

While gold does not react and so on, it is very soft so if you want to use it in jewelry it is always mixed up with palladium (white gold) or copper.

Gold is conductive. This is great but how does that happen?
Well gold and silver and copper are in the same column which means that they have similar properties. All of them are very conductive because they have one free valence electron.
So gold for example has configuration: 4f14, 5d10,6s1
“d” and “f” orbitals are both full since “d” has limit of 10 electrons and “f” 14.
You could ask why other elements with one valence electron are not so conductive and it is because the farther away from the core of the atom the easier it is to break the electron free. Also different atoms have different ionizing energy which means that it takes different amount of energy to free their electron.


Before I get to mining of gold I will mention the places where you can find it.

In the Earth’s crust there are about 0,0075-0,01 ppm of Palladium about which I wrote earlier. There is about 190 ppm of Vanadium but for gold it is: 0.0031 ppm. Which means that there is not much of it.

Unlike Palladium, gold was detected in the ocean to be 0.011 μg Au/l.
In whole Universe the estimated value of Au is one atom per 300 billions of hydrogen atoms, which is ten times less than palladium.

This is only guess but I think that this could be caused because in supernovas it is surely much easier to create element with 33 less protons.

Lets see how it looks like for different countries. The list of the countries is taken from Wikipedia and it is measured in tons (it is for mining in the year of 2013).

  • 1. Čína China 420
  • 2. Austrálie Australia 255
  • 3. USA USA 227
  • 4. Rusko Russia 220
  • 5. Peru Peru 150
  • 6. Jihoafrická republika South Africa 145
  • 7. Kanada Canada 120
  • 8. Mexiko Mexico 100
  • 9. Uzbekistán Uzbekistan 93
  • 10. Ghana Ghana 85

It is assumed that there were altogether mined 175,000 tons of gold. If you would pile it, it would use the volume of 21 cubic meters. While you may say that this is not much, imagine it standing next to your house + gold is very heavy. If you would make the same pile from hydrogen it would be about 200 times as large.

On the map below you can see the approximate storage of country’s gold (you could easily criticize it, look at South Africa.. but I did not find better, just don’t take it to be a good source).

There are few ways to mine gold. The older one, which you may have seen in movies and it is not used anymore, is the method of panning. This is based on the effect of gravity which pulls heavier gold down to the bottom of the bowl while the rest of the sand is slowly floating away (this was used often in rivers).

The modern way is to crush the material to small pieces and then leach it in some acid, rich in chlorine ions. It is then excluded in electric current on the cathode. There was also way to get it using mercury but only in specific situations and the soil was polluted with mercury.

Now there are ecological problems all the same because of hydrometalurgy which is the process of getting metals from their ores. There are huge amounts of cyanides used which in history already happened to cause some disasters, polluting large rivers and letting them toxic for years.


For the last chapter lets get to usage of this amazing metal.

In history the first usage was only jewelry. This is obvious since people back then did not even know what electricity is and they did not have enough gold to make isolation from it but it has such a nice color so they made lot of jewelry.

You can surely find lot of rings and various necklaces, this one is ring of Egyptian pharaoh. Like I said at the start, now gold is mixed with some other metal so it is not so soft.
You can see that metal gets different colors depending on the percentage of all the various metals.

Most often the objects are not whole made up of gold but rather only the top layer which can be extremely thin, even transparent.

Even in food you can find gold like a decoration, it is tagged as E175 and it is not dangerous at all since anything in human body is, won’t react with gold.

In industry, the property of high conductivity is used in computers in processors.

In dentistry gold is used as dental alloy, because again it does not react. There is not only gold but other metals too, mercury for example (because of Hg it is important for the alloy to not react and survive the environment in mouth).
I still remember when I went with my grandmother to guy who was collecting gold with her old golden dental alloys.

Gold was used as backup for money, this was called gold standard and I am going to write a whole separate post about it. This system fell and it is not used anymore.

Gold is even used by NASA. I read that for some flight there was 43 kg of gold used. To give specific example, there is gold used in astronauts helmet. This is because of radiation in space where you are not protected by atmosphere.
Gold foil will reflect most of the ultraviolet and infrared radiation which could otherwise cause serious damage to astronauts eyes. Full explanation.

This is all from me for today, already this has been the longest post ever so I hope someone will read it.


Cube of gold
Map of world gold storage
Other images from wiki articles about gold and gold mining and aqua regia




WTF? A conspiracy? 7) Perfect pictures

it has been a long time since I posted about the Moon hoax but today I am returning. So I found that moon hoaxers think that Apollo must be faked because the pictures taken on Moon are strangely good.

Oh wow, that’s right. All of the pictures look like they have been taken by experts who had enough time to put everything right where they wanted. I mean look at it. Buzz saluting during Apollo 11 mission is perfectly placed in the image next to the “waving flag“. And yes there are tens of similar pictures and all of them are so good. OMG!

Fine, it took some time but finally I found the one you can see below.

I mean, ok clearly this picture is not good one, that is obvious since Armstrong steps out of the picture while it is taken.

I am really curious what would hoaxers say to this, it is from Apollo 11 archive

Next one is not good either, the lunar modul is cut on the right.

Fine there is clear mistake on the hoaxer’s side. They assume that they would see a bad picture in magazine? Or in TV? Really that is just so dumb!

Phil Plait on his bad astronomy says that in fox show about moon landing they called some NASA expert on Apollo cameras and they asked him if he knows why those pictures are so good. Well I can imagine that I would not be able to come up with answer right away while someone is recording me for TV show, while trying his best to put me down.

That is all for today.



Choking black holes

people usually think about black holes as objects that will put end to anything near them tearing it apart and swallowing it for ever.

Part of this is actually true but black hole may have a problem with this because of Eddington limit.

So just a few sentences about black holes, it is collapsed massive star. There is event horizon around it and it is the region from which the escape velocity is equal to speed of light, if you cross it, you are doomed.
Astronomers observe black hole choking on a Star
Around black holes accretion disk may create. Accretion disk is disk composed of any matter (usually some hydrogen or maybe pieces of comets or asteroids). It is heated through friction and it rotates in high speeds around the black hole.

There is lot of radiation created in this process. If the object around which it rotates is smaller, some infrared radiation will be emitted. While black holes or neutron stars may emit even x-rays.

This radiation is stronger the more matter is falling into the black hole. At one point there is so much radiation that the matter will be blown away from the black hole (or star or neutron star) resulting in decrease of the radiation. When it decreases the matter will fall back to the object (not all of it) and again there is tremendous amount of radiation released, then it continues.

Every time there is tremendous loss of matter. This is for example the explanation for one star named on “c” (cygnus or something) which was losing matter sometimes in great amounts which could not be solar wind but it was this choking and exceeding of Eddington limit.

Eddington limit or luminosity is the top border for luminosity of star since if it exceeds this limit it will start to choke as I described earlier. This limit varies from object to object and it also depends on the material on which it is choking. For example if it is helium instead of hydrogen, the limit is much higher since helium is heavier element.

To read further about black holes, choking and so on, check out those pages:
Choking of black hole
Formation of accretion/debris disk around black hole
Black hole choking in the year of 2009
Kurzgesagt video: first, second


1st picture

Optics: 4) Measuring dioptre

today I was doing the best thing in optics to date. I was measuring the dioptre of my glasses (yes I wear glasses) and also I measured the dioptre of my magnifier (yes I measured it but then I figured out that I did it wrong so I will skip it).

Ok, before I get to the measuring and how I did it I will explain how lenses work because in last episodes what I did were only mirrors.

The difference between mirrors and lenses is that mirror reflect light while lenses let it through while changing its direction of travel.

There are several types of lenses which can be sorted to two main groups Pic1, Optics 4of convex lens and concave lens.

On the huge picture you can see the six types. The first row are convex lenses. First one is called biconvex lens then planoconvex lens and the third is concave-convex lens. You can see than there is always convex which hints for the first row, for convex type.

It is similar with the second type, those are biconcave lens, planoconcave lens and convex-concave lens.

I know this is cool, what can we do with this?
This equation which you can see on the left is the equation for lens which is thin. This means that there is no space between the arcs of the lens by this I mean that the arcs touch . Those arcs you can see on the right of the first picture. r1 is radius of the first arc and r2 of the second. f is the focal distance, the distance from focal point to the middle of the lens. The thing here is that lens has two focal distances, that is because it is made of two parts separeted by the vertical axis as you can see on the next picture. Also this whole equation not only equals to 1/f but also to φ(phi). The unit of φ is dioptre so φ=1/f. If f increases dioptre decreases logicly. So if someone has glasses with 4 dioptre his focal distance is 25 centimeters because dioptre is measured in meters!
This equation can be used both for concave and convex lenses of course (but concave lens will have r negative).

n1 and n2 are the refractive index of the glass which is around 1.6 and of the stuff where the lens is in, air, water or something else (n2 is the higher one).

You can find lot of problems on this equation and I did some from one book. It is good to exercise some of them because then you will feel much better on the stuff you are actually doing.

Now last thing before I get to the glasses, lets see how convex lens react to the three main rays which I mentioned in earlier postsPic2, Optics 4 (I will do the concave lens next time because I did not get to it yet).
When the candle is in about twice the distance of the focal point you can see that the size is fairly similar and what concave lens does, is that those light rays which are going from each other will be headed back towards the same point where the image will be formed. Of course the problem is that you wont see the picture of something when you put your lens from your glasses on the paper. It is because there is whole other bunch of rays from all different sides that will disturb any image that could be made.

Pic3, Optics 4When you look on the picture above, you can see that blue and green line were not able to touch anywhere which is the same thing that happened with the mirror when you put something between the mirror and focal point.

This image is enlarged and not true image since the rays are not actually going that way but our eye thinks so.

I was measuring the dioptres of my glasses. For the right eye I have -2 dioptres. You see it is very important that it is minus because that is what is saying that it is concave lens.
I took the glasses and drew line on the paper of their bottom side, which I then expanded and tried as accurately as possible to find out the radius of this circle 9.2 for the inside of concave lens and 12.8 for the outer part.

Do not forget that those glasses are concave convex lens which also means that the inside is -9.2 because it is “negative” of the glass.

When I gave it to the equation I found out that focal distance was 54.52 centimeters and dioptres -1.8342 which is not very close but since the way I was doing this was not meant to be very accurate I could not get anything better. (I took the refractive index of glass to be 1.6).


PS. this was my 100th post!
PPS. I will update about those glasses because I am not totally sure yet how they work so stay tuned.
Picture of equation
Picture of magnifier


Famous people: Galileo Galilei

for Christmas I got some nice books and now I am reading first one which is called: 10 Physicists who transformed our understanding of reality. It seems that it is very good book and I am behind the first chapter which was about Galileo Galilei so I decided that I will write about him.

So Galileo Galilei is very famous astronomer but why? Because of Galilean moons, yes that is right and also because of his first telescope and probably even because of his conflict with church.
Galileo technikou vědecké metody učinil významné objevy ve fyzice a astronomii.Galileo was born 15.2.1564.
It was time when most people thought that everything is made up of four elements and the fifth, quintessence was present in the sky. Not many people questioned those ideas. Lot of stuff was based only on thinking because it was thought that sense was easily fooled in experiment.

Galileo was born in Pisa to his father who was lute player. First he wanted to be priest but father rather wanted him to become a doctor.
Galileo had private teacher as did other mid class kids and soon he discovered that he was more curious about science than in priesthood.

He started to visit university in Pisa when he was seventeen.
There are some stories about his curiosity for all the things around, like throwing stuff from the Pisa tower or watching how pendulums swing.

For example he soon discovered that it is not true that bigger things will hit the ground first like Aristotle thought.

He left the university because his biggest concern clearly was not medicine but rather mathematics. He took some courses to become professor.

In 1595 he started to investigate the problem with tides. Nobody was able to explain them properly before because they were such a strange event, high and low tide twice a day.. geocentric model which was the only one recognized back then was not able to explain it.

This seems to be the first time that Galileo started to think about the heliocentric model first proposed by Copernicus.
Galileo wrote Kepler when he read his pro-heliocentric book. They were writing letters to each other for some time when Kepler told him that he should try to investigate stellar parallax[1].

Galileo finally did not even try because he thought that there are already people, who tried hard enough so he would not be able to measure it. It was measured for the first time in the year of 1838.

Instead of investigating stellar parallax he returned to pendulums and started to make experiments about their swing. It seemed like paradox that no matter the angle of the swing the swing will always take the same time. This was about when he discovered the first law of motion and inertia.

In geocentric model it is thought that Earth is the middle of Universe with everything rotating around it in some kind of shells. The sky is unchangeable so everything that changes must be in sub-lunary sphere[2].

It was October 1604 when supernova was seen from Earth. Galileo thought it is new star but he “knew” that the sky can not be changed so it hat do be in atmosphere where he would clearly see that parallax which I mentioned earlier.

Galileo measured its position on few places in Europe and it did not change, so clearly this model of world was wrong.

After this he constructed his best telescope with magnification of 20x. First of all he found out that the surface of Moon is not smooth as it was thought. Then finally he started to watch Jupiter.

First of all he saw three star like object around it. He thought that those are just normal stars but few days later one of them disappeared and another was visible. This was how he found Galilean moons.

It was another breakthrough since before it was thought that everything has to be orbiting Earth.
Another thing that ensured him of heliocentric model was Venus. He found out that Evening Star also goes through the cycle of “new moon” and “full moon” as Moon does. This was not possible if Venus should be orbiting Earth and at the same time rise as evening and morning star. Also he found out that when Venus is going to be in full moon it is also smaller than in new moon (it is farther away!).

The problem with these revolutionary ideas was that it was clear that church wont like to hear it.
First he only said it to Kepler but than he wrote some books.
Galileo was deeply religious man so he did not want to discredit church but rather show that there were some “small” mistakes.

Galileo thought that when he will show both sides of argument it will be perfectly fine but finally church called him for trial in Rome.
The final sentence was to put him under home arrest and that he will have to rewrite the offensive parts of the book.

I read that there is myth that when they said that he was to be at home arrest he said: “And yet it moves. (the Earth)” but as they stated in the book, he was not stupid to mutter such a thing and there is no evidence for it.

He died in January 8th 1642.

Galileo clearly was really great mind who not only explained perfectly heliocentric model but also showed the ways modern science works.


Galileo Galilei picture.

[1]Stellar parallax is something you see everyday and it has to do with the position of the things around you. When you are driving car the stuff close to you is moving faster than the stuff which is far away from you. It is called stellar because of the different parallax when you are looking from various point on the orbit of Earth.

[2]Sub-lunary sphere is what lies under the orbit of Moon. It is changeable while supra-lunary sphere is what is above the Moon’s orbit. It is regular and it can not be changed.

Moons of our Solar System: Europa

here comes the post about another moon of our Solar System. This time it is Europa. Europa the awesome moon with so white surface and those red streaks across but still the smoothest crust, Europa another Galilean moon!

Europa is very famous moon. It is also very large, sixth moon in whole Solar System and 15th object in size in whole System.
Europa-moon.jpgLike all other Galilean moons this one was also discovered by Galileo Galilei who named it Jupiter II and independently by Simon Marius who called it Europa after Zeus’s lover.

I think that Europa is very well known do to popularization of high chance of extraterrestrial life there. Probably also because of that enormous water ocean under its surface.

First of all lets look at its enormous size.

On the right you can see for comparison the size of Europa, Moon and Earth.

Mean radius of Moon is 1,737 km while for Europa it is 1,560 km. Mass of course is lower. This corresponds with density. There is 0.3 g/cm3 difference, which is not much.

Moon orbits at 380,000 km while Europa at 670,000 km. As I said in previous posts Ganymede, Io and Europa are in orbital resonance.

This means that Europa’s interior is heated by friction.

Surface of this moon is the smoothest in whole Solar System. This seems to be from the process of water running from under the crust of ice and smoothing everything out. While there are no high features, you can find there things called penitentes. Those can appear on Earth in high altitudes when snow sublimates in temperatures below zero. It creates those snowy spikes.

If you look on the first picture of whole satellite you can see that there are those red stripes.
It seems that they are created by “hot” ice flowing sometimes from under the surface. This also hints to plate tectonics on other object than Earth.
There is extreme radiation on Europa, about 5,400 mSv which is a lot and it would kill you in about a day.

Under the surface which is made of silicate rock and ice is gigantic ocean of liquid water. It is liquid because of pressure and the friction which causes its temperature to rise.
This is why astronomers think that there could be life.
There are some missions planned, one of them is very interesting and it requires some robot to land on Europa and by heating to melt down through the ice crust towards the ocean. The heat would be made by radioactive fuel.
This thing would have to be very well sterilized so it wont find its own bacteria in the ocean. Hydrobot (on the right) would be dropped there and then it would collect samples and analyze them right in the ocean.

The volume of the ocean is more than twice as much as on Earth and it may be 100 km deep.

Because of enormous tides made by Jupiter, there are water plumes of water vapor which are 200 km high. Those plumes may carry about 7,000 kg/s of material.

Europa has atmosphere but it is not very thick with pressure of 0.1 micro pascal. This atmosphere is made by ionizing radiation hitting the ground and leaving some free atoms which than become the part of atmosphere. Part of the oxygen in atmosphere is made by process called radiolysis.

To date there were already couple of missions which saw Europa from close distance, while yes, we can see Europa even from Earth because when its whole surface turned to us is lighted its apparent magnitude is 5.27 which is pretty good.

First picture taken from close distance was this one on the left. It’s Pioneer 10s picture.
Also Pioneer 11 saw him year later (1974) and after this Voyager 1 and 2 took much better pictures. First satellite to orbit Jupiter was Galileo which was working for 8 years and then it’s course was changed towards Jupiter’s atmosphere.

For now there are planned some missions that would again orbit Jupiter and collect data about its moons especially Europa because of the ocean.
For direct studying of Europa there is planned mission called Europa clipper, which would investigate its habitability and also planned is JUICE – Jupiter Icy Moon Explorer, but this one would be mostly observing Ganymede.


All pictures are from here.

Optics: 3) Spherical mirror

hell yeah! Here comes another post about optics. This time I will be writing about spherical mirror, its properties and how light behaves when it hits its surface.

On the left you can see the spherical mirror. Black line indicates the edge of the mirror while the other line is the axis of the mirror. Pic1, Optics 3

C is the center of the mirror. F is the focus and v is the top, or vortex.

Below you can see the light rays colored.

There are three main types of light rays hitting this kind of mirror.

There is the blue one which is called parallel ray. It is parallel to the axis and when it hits the surface of the mirror it is reflected toward focus. Actually when it is far away from the axis it may hit some different point (but that is not important right now).

Green one is called the vortex ray. It is coming to vortex where it is reflected in the same angle. On vortex, light behaves the same as when it is hitting normal flat mirror. The last and red one is focus ray, which comes through focus and is reflected in parallel with axis. The last one is actually reverted parallel ray.

Using these three rays you can get the place of the reflection. Of course in normal light there is tremendous amount of rays which than create an image.

Pic2, Optics3

On the next picture you can see the image of candle/flame reflected using these three light rays.
This kind of picture is turned upside down and when the candle is so far away it will be smaller. If it gets closer at one point, both sides will be the same and then at on point when the candle will be between focus and vortex, another thing happens.Pic3, Optics 3

So here you have the candle between focus and vortex. This means that there is no red ray/focus ray because it is not reflected  by the mirror. But your mind things that blue and green ,which should never meet, are going in straight line behind into the mirror which than creates bigger apparent picture.

So this is for the reflection basics now lets see the math behind.
This one on the left is rendering equation.
“a” is the distance of the object from the mirror.
“a'” is the distance of the reflection from the mirror.

“f” is the distance of vortex and focus. You can see that if “f” is bigger the fraction is smaller which means that the other side has to be smaller too so “a” and “a'” will get bigger too since the distances are bound to each other (and they are in denominator). If “a” is bigger than the reflection is closer to vortex which means that “a'” is smaller.

The last one is called something like transversal enlargement. From Z which is dimensionless you can know if the reflection is bigger or not because “y'” is the height of the reflection from the axis and “y” is the height of the real object. If Z is 1 then both real object and reflection are the same size. If Z is bigger than one than the reflection is bigger which hints for the last picture of reflection. If Z is smaller than 1 than the reflection is smaller.

Z can be also calculated using the distance from vortex:
This works similarly. If Z is smaller than 0 then the picture is reverted. And everything else works as well because it is actually the exact same equation.

Also you can get the place where the focus is when you are measuring something which is far away. This is because when it is far away almost all of the light rays are going parallel to the axis. When it is about 10 meters there is problem with your accuracy.


The pictures which were drawn by hand are made by me so I have all the right for them (actually feel free to use them using Creative Commons License)!

1st picture
Rendering equation
Transversal enlargement

Observing Supernova

so what I just found was very very interesting and it is about observing of Supernovas which are those exploding stars or white dwarfs.

The problem with observation of these very bright objects is that first of all there is not much of them and second, it is extremely hard to catch the start of the explosion so we do not have much data about it.

This problem seems to have really awesome solution that is based on nothing else than Einstein’s gravitational lensing.

Gravitational lensing is effect of very massive thing like black hole or galaxy or even galaxy cluster. It can increase the amount of light coming to us or bend the light. So actually when you are looking to star right next to Sun it may appear on different spot than it actually is!

Actually I am pretty sorry but not only that you see everything in past but you see it actually on the wrong place, DAMN! (And if you run it is bluer).

So because of this light bending it can happen that the light even comes from different directions.

The picture above shows how we could observe one event (one supernova type Ia) four times in different time intervals just because it was in huge super cluster which bend the light from supernova so much that it came to us in different directions.

This particular observation was done only by accident when one astronomer was looking at pictures from Hubble and he saw it.


Supernova picture
Gravitational bending

PS: today I have reached 400 visitors!


Elements of Periodic table: 2) Palladium

this time comes the post about another element of periodic table. Last time it was Vanad and I will continue with Palladium!
Palladium is extremely important in car industry, it is also beautiful in jewelry and has surprising history.


What I found most interesting about Palladium (Pd for the rest of the post) is that it is related to astronomy.
In the beginning of 19th century guy named William Hyde Wollaston was PallasHST2007.jpgable to separate Pd and then he published it in a scientific journal. Some people thought that it was fake, that what he called Pd was just some kind of alloy of Nickel and Silver. Wollaston named it after dwarf planet found two months earlier called Pallas, you can see the planet on the right (Pallas is second largest dwarf planet in the belt between Mars and Jupiter).

Palladium (46 Pd).jpgPalladium is white and grey metal right above Platinum in the table of elements. There are many isotopes and lot of them naturally occur and few of them are radioactive decaying into Ruthenium, for example.

It is used on various things. In cars it is used as part of catalytic converter which is next to motor and takes CO and other toxic and poisonous molecules out. For the converter to be fully functional we had to stop using leaded petrol. (Wikipedia says that there are still companies in China that produce tetraethylead which is the source of the lead in petrol, it is making the car more efficient).
Pb (lead) was destroying these catalytic converters in very short time while now it is assumed that it should be working for over 120,000 km. On the left you can see the three way catalytic converter.

Palladium is used a lot in jewelry like “white gold”, also in dentistry because it is cheaper than gold, but some people may be allergic. Smartphones and lot of various electronic devices contain Pd.
Pd is also used as storage for hydrogen.

Now for mining. Most of Pd is mined in Russia,
South Africa is right behind then for a long time nothing and rest is produced by USA and Canada mostly.

Some sources say that Russia is running low with their storage, which would be big problem if true (it is the state secret so no one can be sure). In 2001 there was a Pd crisis when Russia had some problems with mining (the problem was linked to politics). Prices of Pd rose to over 1000$ per troy ounce (OZ=27 grams). It seemed that it would rise even more so Ford Motor Company bought a big amount and then the prices dropped rapidly, leaving Ford with loss about 1 billion $! On the picture below you can nullsee the peak of the price and then the drop to about 200$. For now the price is about 560$/OZ for the last years the price seems to drop. On the next picture you can see the graph of prices for 18th December which of course do not 1 Day Spot Palladium Prices - Palladium Price Chartchange very much. In whole Earth there is about 0,0075-0,01 ppm (mg/kg) of Palladium. PPM is parts per million which is the same as miligram per kilogram. In sea water the amount is unmeasurable, because even the most precise technology is not able to detect it. In space there is about 1 atom of Pd per 30 billions of atoms of hydrogen.

Pd is also created in nuclear reactors but this source is not used.

Usually you will find pure (100%) palladium with gold or ruthenium around. Also oxygen is not reacting with Pd, which is extremely good attribute (this is not true above 800°C, then PdO is created on the top layers). For some time Pd was used as cure for tuberculosis but there were many side effects so it was banned. Pd is not very toxic since our body is not able to absorb it, but there is some evidence that it may be carcinogenic.


Pallas picture
Palladium picture
Catalytic converter
Palladium demand
Pie graph of production
Kitco 2001 graph
World map of Pd production


Red shift once more

so last time I was writing about Doppler`s effect and I was using normal Doppler`s effect but actually I forgot something very important and those are relativistic speeds.

Relativistic speed is the speed when Newtonian physics is no longer able to accurately predict what is going to happen. This can happen from 1 to 10% of speed of light. This border is hard to define since it is hard to define when Newtonian physics is not enough accurate.

On the left you can see graph of increasing mass when you increase speed.

That is one of many relativistic effect, this also means that when you are walking you are heavier. Also another effect is time dilation for example.

Time dilation is the problem with red shift in Universe. You can not just use equations like I used before but you need to use special relativity with time dilation, since the thing is speeding away from you and the time runs differently for you and it.
z + 1 = \frac{\lambda_o}{\lambda_e} = \sqrt{\frac{1+v/c}{1-v/c}}This equation is the right one, more accurate for huge speeds with which you will be in astronomy probably dealing with.

Lambdas are the wave lengths of the one you are observing and the real one of the object. V is velocity and c speed of light, z is the red shift.

So I checked with one problem which I found on the internet. It was about quasar far away which is moving in high speeds. The red shift is 0.158.

So i used this calculator to find out what is v/c which was 0.14656. With this I found out what is the speed which was 43,695 km/s. Then I put it in the equation above and the red shift was about 0.15777 (something). So I can see that I did it right and this equation is truly giving us the red shift.


1st picture
2nd picture is from czech wiki article about relativistic Doppler effect