In the very beginning, only the element Hydrogen H existed. It didn‘t take the form which we understand on Earth today but a form known as ‘Plasma‘. These clouds of plasma expanded and cooled rapidly, the hot and glowing, red clouds beginning to fill the vacuum. They are situated in the so called H-II regions (say H Two) in Space. Plasma means, that the two components of hydrogen, the proton and the electron, had not yet combined into elementary hydrogen. Enormous heat prevented the forces of attraction from bringing them together as an atom. In such an extreme environment with matter in this state, the hydrogen is known as "ionized". Hydrogen‘s particles can fly freely in space where-ever they choose. Under these conditions, the gas no longer has any electrical resistance, the situation being reproduced under laboratory conditions for the first time in 1996. The gas became a superb conductor, in which state hydrogen is known as "Metallic" hydrogen. It therefore follows that high currents can flow and equally, strong magnetic fields can be formed. Crucially, to the later birth of stars, is that these clouds of ionized hydrogen were present in different densities in space. These places later became the stellar nurseries of Stars.
The Atomic hydrogen (1H) is the most flimsy of all of the known 93 natural elements. It consists of a proton encircled/orbited by an electron
When space temperatures were sinking and plasma ceasing, electrons, no longer held apart from protons, could now be captured one by one, by those waiting protons, building an elementary hydrogen molecule H-I (said H One). This very process can still be detected today, with the help of Radio Telescopes. The radio emission of H-I clouds radiates at a wavelength of 21 cm and is a pointer to regions where stars are being formed. Clouds expanded ever more & with the lower temperatures, the molecules which we know on earth were formed: the so called H2 appeared. This molecule is the forerunner of the even more famous H20, water which is well known as the basis of life. Pure hydrogen H2 the lightest element, was used for lifting the Zeppelins in former years. (Unfortunately it is highly inflammable). Gravity started to control the huge clouds formed by hydrogen, re-condensing the clouds further, causing sudden rise in pressure and temperature. Stellar nuclear fusion was researched by Robert Atkinson, Ernest Rutherford and Hans Bethe, amongst others.
When temperatures reached approx. 15 million degrees Celsius, a complex process started. Suddenly, the transformation of two hydrogen atoms into a helium atom with the help of two neutrons began. Fulminating stars occurred, radiating everywhere in space, by a process in the name of Nuclear Fusion. By the laws of Physics, helium is slightly lighter than the 2 hydrogen atoms plus the 2 neutrons from which it is constructed. Therefore some mass is missing. Einstein´s formula E = mc² accounts for this. The missing mass is converted into pure energy as in The Sun. This energy can be seen as light but also there are other components released, occurring as heat and ultra-violet radiation, quite invisible to human eyes.
An example for Nuclear Fusion is The Sun
The transit of Venus across the face of the Sun in June 6, 2012. The planet Venus is to be seen as a small black dot in the upper right corner of the picture (taken by : R.Brückner)
The name Helium comes from the Greek word Helios which means "sun" and was discovered relatively late – compared with the other 92 elements, by the French astronomer Jules Janssen who had joined a scientific expedition in India in 1868 to study a total Solar Eclipse. For the very first time, a new element was found, not on Earth but out in space.
Here on Earth, the inert gas helium is used in gas glow lamps and also in airships like the Zeppelin, this because of the fact that helium is lighter than air. It will ascend until it reaches a certain altitude. For that reason and because it will not burn, helium is a perfect lifting gas for airships. In former times the highly inflammable gas hydrogen was used for filling airships – once with drastic consequences.
The Hindenburg disaster: The famous picture of the tragic burning of "Hindenburg" in 1937. The German passenger airship had just arrived in Lakehurst close to New York. Of the 97 people on board, there were 35 fatalities (Wiki)
We have learned that the basic element hydrogen, was formed the stars approx. 400 million years after the Big Bang. This process is ongoing but reached its climax about 4 - 6 billion years ago. At that time, our own Sun was formed. The birth of suns is still not finished. It can be stated simply that suns are really huge ovens fired by Nuclear Fusion. This means that hydrogen will be converted into helium with the emission of light, heat and other forms of electromagnetic radiation. Stars usually aggregate in the form of star clusters. Such star clusters belong to the oldest formations in the celestial sky and are a favourite target for telescopes of many Astronomers.
The star cluster M13 in the configuration Hercules, is one of the most beautiful in the Northern Hemisphere, newly created, closely following the Big Bang. Its distance from us is approximately 25,000 light years and it comprises thousands of stars like our Sun – Picture taken by Martin Elsässer of VSW Munich
Stars do not solely burn hydrogen into helium but are also able to create further, heavier elements. In so doing, step by step, all of the 92 known elements were built. This includes Carbon, the element with which humans and all organisms are formed. However, the elements which form our planet and support life on it, did not originate in The Sun. It is too young. The carbon came from earlier stars at the formation of space, further back in time than when the Sun and planets of our Solar System were being assembled. It can be stated categorically that humans are derived from "Star Dust" which means hydrogen. The electromagnetic radiation of the Sun appears in the form of light and heat at about 1000 watts per square metre. It also contains radiation in all forms of electromagnetic waves e.g. radio waves, ultraviolet light, throughout the spectrum, to include XRay and Gamma Rays. Medical science reveals that electromagnetic rays with wave lengths of kilometres and metres, as used by Radio and TV Stations and even mobile radios/phones are not harmful to humans nor animals.
However, the shorter the wavelength, the greater the hazard and so with increasing frequency, (because wavelength and frequency are reciprocal) a critical limit is reached and the threat of skin cancer looms. The threat of carcinoma increases, the shorter the wavelength becomes. A dangerous type of radiation is ultraviolet rays from the Sun. Fortunately, the atmosphere over our head protects us by absorbing this dangerous radiation. Despite that, the atmosphere is very thin, just 30 kilometers. We still need to take care against exposure to UV radiation.
According to the Big Bang theory, the expanding Universe cooled to 10 degrees Kelvin, corresponding to approximately minus 263 degrees Celsius. Gravitational forces gathered dust around The Sun, more and more. Planets were formed. A planet – in contrast to a Sun – does not radiate. As its mass is too low, fusion cannot occur. An excellent example of such a planet failing to achieve the status of sun, we can see in our own solar system. It is the planet Jupiter, containing approx 1/80 of the mass of our Sun. The constituents are mainly pure hydrogen with other forms of gas like methane, ammonia etc. This means, Jupiter has no hard surface as does Earth but a soft one. It is a gas planet.
If Jupiter had become slightly heavier, the process of fusion would have commenced in its interior. In that case we would now have two Suns in the sky with all the inevitable consequences, one of them being that there would hardly be any night. Binary systems having two stars are not rare in space. Even systems with three or four stars can often be found.
Binary and triple systems are popular subjects for the telescopes of astronomers. They were detected easily, even in bad viewing conditions from cities, and are easy to capture on camera. There is a certain fascination in so doing at widely separated time intervals and then to observe the movements of the stars in their positions, respective to each other.
The aggregation of matter was observed for the first time aboard the International Space Station ISS in 2013. An astronaut conducted an experiment allowing flour and powdered sugar to float in a glass container. He was able to observe and document how particles aggregated under the influence of gravity. Tufts of dust formed like snowflakes within the glass container. It can be assumed that the same laws causing these, also came into play in space, creating similar ‘tufts’ of interstellar matter and consequently planets and suns. The kinetic energy generated by the power of the Big Bang led to a common direction of motion around a common centre, appearing as a disc from a distance. In consequence, all planets are in the same plane orbiting their sun. Suns having planets, seem to be the standard configuration in the Universe. For some years now, hundreds of them have been detected. Detection is not easy because planets are relatively dark compared to their sun. They can be detected by a method known as spectral shift.
In 1995 a planet outside our Solar System was first discovered by Michael Mayor and Didier Queloz at the University of Geneva. The exoplanet is called 51 Pegasi b and orbits its sun in four of our days. This big planet is situated in the constellation Pegasus, at a distance of approx. 40 light-years. These kinds of planets also are called "Hot Jupiters". It is a class of planets having the size of our Jupiter, heated extensively from its sun by virtue of close orbit. In successive years, hundreds of exoplanets of various sizes were discovered and in many constellations, being almost invisible amd difficult to detect. For that reason, detection was not carried out using standard techniques, i.e. optical telescopes but by analysing the spectral lines of the central suns whose lines are shifted by the influence of the orbiting planets. Nowadays almost every sun is expected to have planets in orbit.
Illustration of the exoplanet 51 Pegasi b. It can´t be exposed on an image because it´s too close to its sun. The contrast between them is far too great (Wiki)
The birth of stars in our Galaxy is not yet finished, probably not in the entire Universe. There are areas where stars continue to be formed. Infrared cameras are well suited for taking pictures of such H-II regions because they glow in red and further, in ranges, invisible to the human eye. The camera on board a satellite like "Akari" is capable of rendering such regions quite visible.
This infrared picture of the Universe was taken from the
Japanese satellite AKARI. Pictured is our Milky Way and the bright regions are areas where stars are formed (By courtesy of JAXA)
One of the most beautiful regions forming stars is situated close to us in the Milky Way, just 1300 lightyears distance . It is within the constellation of Orion, appearing during winter in the Northern Hemisphere. There is a big glowing nebula, visible to the naked eye, just at the centre of that configuration. (See next page)