The universe

The universe


Introduction

The universe can be defined as the whole of existing things from the scale of sub-micron to outer space. It consists of approximately 100 000 000 000 (one hundred thousand million) galaxies, each containing approximately 100 000 000 000 stars. The most distant objects that we know of are quasars, some 16 000 000 000 light years away. The age of the universe is approximately 15 000 million years (Ma) or 15 billion years (Ga), though there is some debate on this. liftoff.msfc.nasa.gov/academy/universe/age.html


Origin of the universe

Recent astronomical observations have shown that the universe is expanding away from a local group of galaxies. This appears to have begun by a huge explosion some 15 billion years ago. This ‘Big Bang’ is the most accepted theory which best explains our present observations on the structure of the universe.

In the ‘Big Bang’ theory, the universe began with a primeval fireball which contained all matter and energy within the universe concentrated within a single body. During the first few minutes, the expansion was dominated by radiation at temperatures of 1011 K (The Kelvin scale is used to measure very high and very low temperatures, 0° C = 273° K). Matter consisted of only protons, neutrons and electrons. Within three to four minutes, the effects of radiation diminished and more complex forms of matter (such as the deuterium nucleus : neutron+proton) evolved. Later, most of the matter became hydrogen (a proton+electron) at a temperature of 109 K.

Hundreds of millions of years after the initial ‘Big Bang’, immense condensations of matter occurred, eventually forming galaxies. Our own solar system is only some 4600 million years old.

Composition of the universe

The universe is composed mainly of hydrogen with approximately 20% helium. All other chemical elements comprise less than 1%. All elements originated as hydrogen. Within the first two minutes of the ‘Big Bang’, hydrogen atoms fused together and helium and lithium were produced. Element production ceased at this point in the ‘Big Bang’ and all other elements heavier than lithium (Li) were produced during later fusion reactions within the interiors of stars.

During supernova events when massive stars exhaust their nuclear fuel in only a few days to months, collapse occurs and the enormous amount of energy caused by intense neutron flux produces the heavier elements such as uranium and gold. The violent explosion also distributes these elements back into space. As the formation of elements proceeds through innumerable star cycles, forming and exploding, the gas and dust produced is slowly enriched in the heavier elements.


Galaxies

The largest objects in the universe are galaxies which can be divided into several types depending upon their shape:

  • Spiral galaxies are the most common and distinctive type (e.g. the Milky Way).
  • Barred spiral galaxies are not as compact as spiral galaxies and have an inner bar which comprises the centre of the galaxy from which arms reach out.
  • Elliptical galaxies are small and difficult to observe because of their low luminosity.
  • Irregular galaxies comprise only a small percentage of all types and lack any distinctive symmetry.
A spiral galaxy in Antlia
A spiral galaxy in Antlia, NGC 2997. Photo: © David Malin/Anglo-Australian Observatory.
A barred spiral galaxy
A barred spiral galaxy, NGC 1365, in Fornax. Photo: © David Malin/Anglo-Australian Observatory.


An elliptical galaxy
An elliptical galaxy, NGC 5078 and its distorted companion IC 879, in Hydra. Photo: © David Malin/Anglo-Australian Observatory.
Large Magellanic Cloud
Large Magellanic Cloud. Photograph from UK Schmidt plates. Photo: © David Malin/Anglo-Australian Observatory/Royal Obs. Edinburgh


Top

Stars

Stars are the most familiar objects in the universe as we can see them almost every night with the naked eye. They vary in size from small white dwarfs to super giants. There are approximately 1022 stars in the universe. They are being formed in galaxies all the time (e.g. nearby stars in the Orion Nebula were born less than one million years ago). Stars shine as they burn-up their nuclear fuel and eventually die. Our sun is an example of a common though smaller than average sized star. It formed approximately 4.6 billion years ago and will most likely last for another 4.6 billion years before it dies out and engulfs all of our solar system’s inner planets, including the Earth.

Groupings of stars as seen from the Earth are known as constellations. They are accidental groupings (that is, they are not in any way related to each other).

The luminosity of a star is a measure of its total energy output. The luminosity scale is measured relative to our own sun (a luminosity of 1). The luminosity of stars varies widely from 10-6 to 5 x 105. The temperature of a star is always given as its surface temperature. These range from 3500° K to 80 000° K (The Kelvin scale is used to measure very high and very low temperatures, 0° C = 273° K). The colour of a star is closely related to its surface temperature. The hottest stars are blue, followed by white, and the coolest stars are yellow, to orange and finally red in colour with decreasing temperature.

  • Supergiants and giant stars are those of enormous size and great luminosity despite having low surface temperatures.
  • White dwarfs are relatively hot small stars with a great density.
  • Neutron stars contain matter which is 1014 times denser than water yet have diameters of only 20 km.
  • Pulsars are small rapidly rotating objects (up to 30 times per second) which emit radiation at regular intervals.
  • Quasars are extremely bright distant objects that extend to the limit of the universe as we know it.
  • Black holes are stars that have collapsed under their own gravitational forces. They are of such high density that their gravitational force is strong enough to even prevent any light or matter escaping.
South celestial pole over water
South celestial pole over water. Photo: © David Miller/DMI.
The super giant Antares and surrounding nebula
The super giant Antares and surrounding nebula. Photograph from UK Schmidt plates. Photo: © David Malin/Anglo-Australian Observatory.


Importance of the sun

The Earth obtains most of its heat and light energy from the sun. This solar energy causes water evaporated on the surface of the Earth to rise into the atmosphere before precipitating elsewhere on the Earth’s surface. Wind is a result of air circulation caused by solar heating. The temperature of the surface of the sun is 6000° K (The Kelvin scale is used to measure very high and very low temperatures, 0° C = 273° K).

The temperature at the centre of the sun is 15 000 000° K.

The sun consists of:

  • an interior which contains most of the mass of the sun and where the sun’s energy is produced
  • the photosphere is the layer from which the sun’s energy escapes and from where light comes from (thickness of 1000 km)
  • the chromosphere has a very low density and is red in colour due to clouds of hydrogen gas (thickness of 500 km)
  • the corona can only be seen during a total eclipse, has a low density and has a temperature of 1 500 000° K

Sunspots are dark markings on the photosphere of the sun between 5° – 35° north and south of the sun’s equator. The sun’s energy is produced through nuclear fusion reactions in which hydrogen atoms are fused together to form helium.

Deformed sun at sunrise
Deformed sun at sunrise. Photo: © David Miller/DMI.
Solar eclipse
Solar eclipse 11 July, 1991, La Paz, Mexico. Diamond ring effect. Photo: © Akira Fujii/DMI.


Measuring astronomical objects

Electromagnetic radiation is the key to our understanding of the universe. It includes all forms of energy that travel through space in the form of waves, visible light, X-rays, ultraviolet, infrared and radiowaves. The electromagnetic spectrum is made up of radiation of varying wavelengths travelling at the speed of light. It is measured and detected using a number of different instruments.

When any element is heated, its gas emits a characteristic spectrum. The chemical composition of many objects can then be determined by examining the spectra of its heated vapours. Conversely, a cool gas absorbs the wavelengths characteristic of the atoms in it.

The fundamental measure of distance in space is the light year which is the distance that light travels through space in one year (9.46 x 1012 km). The speed of light is 300 000 km per second.

The Astronomical Unit (AU) is the mean distance between the Earth and our sun (measured in kilometres).

source:http://www.austmus.gov.au

About Rashid Faridi

I am Rashid Aziz Faridi ,Writer, Teacher and a Voracious Reader.
This entry was posted in Solar System. Bookmark the permalink.

1 Response to The universe

  1. ORIGIN OF UNIVERSE- A NEW PRINCIPLE
    Propounded by Dr. Hari Om, Sr. Scientist Agronomy CCS HAU, Hisar (Kurukshetra)

    According to this principle, which is called ‘Principle of Cipher Zone’, the universe was originated in a series of four steps, i.e., four sub-principles are involved in this process. These sub-principles explain the origin of universe, its dissolution, basis of its expansion and status of energy in a star.

    The Principle of Cipher Zone propounds that the theory of ‘Big Bang’ is not responsible for the origin of universe, but this process advanced in a series of steps, which did not involve any vast explosion of the energy like Big Bang. It started as the process of formation of a star initiates. Today, the completion of this process takes lesser ?time’ as it was taken for the formation of first star, because in the present universe, the material required for the formation of a star becomes readily available, but initially it was not so and this process proceeded very slowly. When the energy of this first star was burnt, it converted into a black hole; but before this conversion, the process of the formation of other stars and planets was initiated and they started revolving around this initially appeared central star. In this way along with the central black hole (converted from the first star) the surrounding stars also formed their own families and kept on revolving around the central black hole. Slowly and slowly, the first Milky Way came into existence. The black hole, which was initially formed, now occupied the central space of the first Milky Way thus formed and simultaneously this central black hole of the central Milky Way went on increasing its size by feeding the surrounding old stars. This way, other Milky Ways also came into existence around the central Milky Way and started revolving around it. All these later formed milky ways also had their own central black holes and found their base of stability from the initially formed central black hole and the central Milky Way like a string tied to the neck of the surrounding Milky Ways with the central one. When all the surrounding black holes merged into the initially formed gigantic black hole, the whole of the universe realized dissolution i.e. Maha Pralya.

    Now after dissolution, there remained only one universal black hole in which the energy of the whole universe turned into waves of almost compatible character with a stable centre of least moving energy having very dense core at the centre. Slowly and slowly the fast moving energy present at the periphery of this black hole went sluggish and slowed down which got scattered with the passage of time. The movement of the energy at the periphery gets faster and faster upto when the outside material in the form of stars, planets, or Milky Ways remains available for feeding, but it starts slowing down once the whole material is immersed in the central universal black hole. In this way, the whole black hole scattered with the passage of time. After that, the process the creation again started. These two processes of creation and dissolution proceed simultaneously through the creation of new stars and galaxies at the outer periphery and simultaneous dissolution of stars and surrounding galaxies into the central black hole of the central galaxy.

    The expansion of universe is also not due to Big Bang, but it is attributed to the size of the continuously increasing black hole at the centre of the Milky Ways. As the size of the central black hole increases, the expansion as well as the speed of the Milky Ways running away from the centre will go on increasing, but a time will come when the outer expansion will be ceased due to extraneous increase in the size of black hole or we can say that increasing density of the central black hole will not allow the further expansion of the galaxy. The incoming energy of the system will dominate over the outgoing energy. With this advancement in the increase of the black hole size, the whole universe will fall and rest in the centre. Every existence or system has a zone of neutral energy at its centre and in its surrounding where its energy ends and the periphery of another system starts. When these two neutral energy zones are merged into one, then the system or existence ceases to work and collapses or we can say that the differential strata of energy of that system are converted into more compatible and unified form of energy or we can say that it is the expansion of the central zone of neutral energy which compels that system to collapse. During the process of expansion, the central zone or black holes of different galaxies goes on increasing. This increase in the area and density of black holes in the middle of the galaxies allow the expansion of the galaxies. The ratio of increase in the area or volume of the black holes in relation to the expansion of outgoing and expanding energy can be assessed with the increase in the ratio of expansion of the nucleus of an atom and the overall expansion of that atom in the form of its mass and energy.

    The working of the system depends on the presence of energy at different levels and the inter- and intra-facial tension in those energy fields. When these fields are merged together, the system collapses or dissolved. In this way, the different systems or existences either small or large are converted into energy waves and this way the process of dissolution proceeds until a sole, gigantic and universal zone of neutral energy or Cipher Zone is formed, which brings the final dissolution.

    This present theory also refutes the finding that a star has the maximum temperature at its core. This theory propounds that a star has highly peaceful zone at its centre; it is not explosive. Every star or system has two types of energy; incoming and outgoing, working entirely at different level and in different direction. The larger is the system or existence, the greater it will have the zone of neutral energy at its centre i.e. a peaceful zone providing stable base to the whole system. The greater is the expansion of the zone of peace and stability at the centre, the more explosive or vibrating will be the surface energy either it is a star like Sun or vast ocean or galaxy. This is true only when the star or the system is composed of similar type of energy at its centre. If the system, like earth, has different type of energy particles at different levels, then the energy will be explosive at its core because of the admixture of different form of energy in the central zone. This is due to the interfacial stress among different types of energy resting at the same level.

    The central zone is nothing but the zone of neutrality, the zone of satisfied energy either it is at the level of smallest particle existing as an atom or largest systems like sea, star or galaxy. The unsatisfied or vibrating or tension creating charge at the surface is the result of the degree of vastness of the internal satisfied power of the system; if measured at the surface of the sea, there is a possibility of the prediction of future rains and devastating thunderstorms or catastrophic Tsunami outbursts. This charge may have its impact on the El-Niño effect and difference of temperature in seawater. If it is measured inside the earth, there can be a possibility of the prediction of earthquakes.

    DR . HARIOM , SR . SCIENTIST – AGRONOMY , CCSHAU – HISAR (KURUKSHETRA)TO ASK hariomkvk@gmail.com & PLZ VISIT TO KNOW MORE http://www.radhasoamitaradham.com
    Radhasoami

    Like

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.