The Universe

The apparent magnitude of Jupiter varies to some extent because of its varying distance from the Earth, but this is not sufficient to explain all the observed changes. Since 1862, the mean opposition magnitude has ranged over 0.45 magnitudes so that, at the brightest opposition, Jupiter was reflecting 50 percent more light than at the faintest. This means that, as the patterns of the clouds of Jupiter vary, the “ALBEDO”, which is the fraction of the incident sunlight which they reflect, also varies. The Albedo also depends on the wavelength of the light or other radiation being measured, but in the visual range it is typically between 30and 50 per cent.

The solar energy that is not reflected by Jupiter’s clouds is absorbed by the atmosphere. If just this amount of absorbed energy were re-emitted then Jupiter would have an effective temperature of 105K, i.e. it would radiate the same amount of energy as a black body of this temperature and of the same size. Most of the energy is radiated at infrared wavelengths. Measurements show that the effective temperature is actually 125K, so that Jupiter is radiating twice as much energy as it absorbs from the Sun. There is therefore an internal energy source of equal power to the absorption of solar energy. This energy source has important effects on theories both of the internal structure of Jupiter and on the stricture of its atmosphere. Spacecraft measurements show that the day and night sides of Jupiter have the same temperature. This implies that the absorbed solar energy is carried to the night side of Jupiter by the planet’s rotation much more quickly than energy is lost from the atmosphere, in agreement with theoretical calculations.

The belts, zones and other features of Jupiter’s atmosphere show that its structure varies from point to point and from time to time. We can however first consider the average structure of the atmosphere and ignore the local variations (weather) and the details of the dynamical processes. Calculations of a standard model atmosphere can then be made.

About 45% of the incident energy is reflected and more than 10% is absorbed fairly high in the atmosphere so that slightly more than 40% must be absorbed by the clouds in the main body of the atmosphere, which is known as the Troposphere. A similar amount of energy comes from the internal source and enters the troposphere at its base. In the upper troposphere the energy is transported by radiation, whereas in the deep atmosphere the main transport mechanism is convection.

Named after the Roman goddess of Love, Venus is the 2nd closest planet to the Sun and orbiting it every 224.7 Earth days. It is also the only planet in the Solar System to be named after a female figure. Venus is also the brightest natural object in the night sky other than the Moon. Since Venus is an inferior planet from Earth, it never strays far away from the Sun. Venus is also often known as the Morning Star or Evening Star as it reaches its maximum brightness either shortly before sunrise or shortly after sunset.

Venus is categorized as a ‘terrestrial planet’ and is referred to as Earth’s sister planet due to the similarity in gravity, size and bulk composition. The planet is covered in layers of sulfuric acid and reflective clouds opaque in color which prevents its surface to be seen from space in visible light. This made it a great subject of speculation and studies until some of its mysteries were shed in the 20th Century through planetary science.

Planet Venus contains the densest atmosphere amongst all the terrestrial planets. The atmosphere contains mostly carbon dioxide since it has no carbon cycle to return the carbon to the surface and rocks and no organic life to absorb it in biomass. The planet becomes extremely hot that the oceans similar to that of earth have all evaporated with only a dusty and dry desert-like scape with rocks. The best theory is that the evaporated oceans and water have been dissociated and without a planetary magnetic field, the hydrogen would have been blown away by the solar wind into interplanetary space.

Venus has not been mapped extensively to date. It was only done so in the last 22 years or so by Project Magellan with evidence to show that there exists volcanic presence. The sulfur in the air have been taken for studies but it still remains a mystery as to why there is no evidence of lava flow to accompany the visible caldera. The number of impact craters are low, indicating that the surface is relatively young; about half a billion years old.

The temperature in Venus is constant due to its isothermal surface. It maintains a temperature that is constant day and night between the equator and the poles. The clouds on Venus are very much capable in producing lightning which is similar to that of Earth’s. It created controversy early on when the first suspected bursts were detected and was only clearly proven in 2006-2007 when Venus Express detected whistler mode waves; clear signatures of lightning.

There are currently ongoing missions to Venus such as that of the Venus Express which was launched on Nov 9 2005. It was taken for detailed studies of the clouds and atmosphere as well as to map the planet’s plasma environment and other surface characteristics such as the temperatures. Due to the hostile conditions, our current technology disallows for the possibility of colonization of Venus. However, there have been increased speculations of building ‘floating cities’ in Venus’ atmosphere in the future.

The queries and arguments about the origin of the universe is just like the old question about the chicken and the egg. It is an issue that is and can always be debatable. Recently, scientists ceased the argument but acknowledge that even in the beginning of the universe, the Law of Science already existed.

Some people such as Aristotle, a Greek philosopher opposed the idea that the universe had a beginning and rather preferred to believe that the universe would exist and had existed something that is perpetual. The fact that the universe is changing with time is an evidence that was accumulated during the 19th century. Geologists recognized that the rocks and fossils have taken hundreds or thousands of millions of years to form, which was according to Creationists, far longer than the age of Earth. Conversely, Boltzmann, a German physicist who discovered the Second Law of Thermodynamics acclaimed that the universe increases with time as measured by entropy.

Most Atheist believed that the universe is eternal and they envisioned that the universe come into existence unexpectedly. This was precluded by Einstein’s theory of gravity and Hubble’s astronomical observations. Beyond reasonable doubt, it is understood that the universe originated in two legitimate options. It may be a intelligent design that someone made the universe or random chance in which the universe made itself.

From the beginning of times, man tried to crack the mystery that covers about the conception of the universe. Myths and legends have arisen just to testify the unrelenting search. Most physicists assumed that the universe is a static universe and had always existed. Because of the swift development of science and technology, the theory of the Big Bang came into view. This theory is based on the cosmological thermal radiation and physical events such as the universe expansion. The Big Bang began when Christian Doppler, a Dutch scientist discovered the Doppler effects which is a physical phenomenon. It further gives reason that everything has come from nothing. The breakthrough about the growth of the universe, completely alters the origin of the universe argument. During the time of the Big Bang, the density of the universe appears to be infinite which gives a shattering effect to all the known Laws of Science.

Many scientists however did not like the Big Bang theory and that is why they came out to the Alternative theory. This theory sustains that the gravitational force of the universe will be able to break the expansion which was assumed by the Big Bang theory. Alternative theory further explains that Big Bang does not jointly created.

Despite all the theories that had been proposed, generally the universe evolves according to the well defined laws that may have been ordained by God. But up to now it was thought that this divine law has nothing to do with the origin of the universe. It is God’s choice if He set the universe going in any way He wanted. After all, the universe would have no choice but to obey the laws that God bestows. Only God can answer the question how the universe began.

For religious fanatics, the age of the universe is one of their main subjects, both in scientific and mythological aspects. According to Isaac Newton the universe could probably be a thousand years only. However Einstein, who developed the general theory of relativity, concluded that the universe was eternal and ageless. When observational evidence happened in 1929, it was proven that his belief was wrong.

For you to know the facts about this, imagine how it would sound like when a person is standing at a train platform. The train creates a noise starting with a low pitch and starts to get high when it moves towards the listener. The changing of the pitch of sound depending on its arrival towards the listener is known as the Doppler shift. This happens when there is a presence of sound and light.

In 1929, observation of isolated galaxies shows that the light coming from it behaves as it moves far away from the viewer. If the isolated galaxies are moving back from us, it means that the universe is expanding similar to a balloon. So what happens if it expands? Obviously, it shows that the universe has a finite age and not eternal or ageless, unlike what Einstein used to believe. But then, how old is it? The radioactivity of the sun and earth explains that the solar system is formed 4.5 billion years ago. It means that the universe was twice as old as the solar system when it was formed. It probably took billions of years when the Milky Way was formed.

It is also reasonable that the universe’s age is at least twice as the earth’s and the sun’s era. It seems that the estimated age of the universe is at least twelve to fifteen billions years old. Perhaps it can be as old as the oldest star clusters. However, there are also mathematical formulas used to estimate how old the universe is. In the early 20th Century, it was said that the stability of atomic matter could tell the age of the universe. It is explained through the Maxwell equation of classical electrodynamics. One of the successes that the quantum equation brought was the calculation of wavelengths in the hydrogen spectrum.

An additional discovery is the Hubble’s law. It happened when Edwin Hubble found spectra of different stars in the universe during his experiments. Hubble’s law suggests that the galaxies and stars that exist in the universe move away from each other and increase their distance for the said velocity, as if it expands like a huge explosion. Hubble found out that the wavelengths of the hydrogen gas were shifted to red due to the amount of proportional distance from the solar system. Hubble’s law serves as an experimental observation that creates a way for modern physics to discover more information.

So the age of the universe is most likely 12 to 16 billion years according to the method of estimation. But according to relativity, time is related to the age of the universe. In some other theories such as the Quantum theory, gravity could be the eternal aspect of the universe.

Uranus, the seventh planet from the Sun is the 3rd largest and the 4th most massive planet in the Solar System. The planet’s name was derived from the Greek deity of the sky Uranus who is said to be the father of Kronos and grandfather of Zeus (Saturn and Jupiter respectively).

Although the planet is visible with the naked eye, it was never really accepted to be a planet by ancient observers due to its slow orbit and dimness. It was not until March 13, 1781 when Sir William Hershel announced its discovery and therefore expanding the boundaries of the solar system for the first time in history. Sir William Hershel’s discovery of Uranus was also accredited to be the first discovery of planet using a telescope.

Uranus is similar in composition to that of Neptune. Both of them differ to Jupiter and Saturn; the ‘larger gas giants’. Astronomers sometimes categorize them in a different category known as the “ice giants”. The atmosphere in Uranus, while similar to that of Jupiter and Saturn ( consisting primarily of helium and hydrogen ), contains “ice” proportions such as water, methane and ammonia with traces of hydrocarbons. It is the coldest atmosphere of a planet in the Solar System with a minimum temperature of -224°C. Uranus also contains a complex cloud structure which is recorded to be made up of water in the lowest layers of clouds while methane is said to make up the top most layers. On the other hand, the interior of the Uranus is said to be made up of rocks and ices.

The only planet in the Solar System to be named after a Greek God with the exception of Earth ( the others being named after Roman Gods ), Uranus has a magnetosphere, a ring system and numerous moons. The configuration system is thought to be unique as its line of rotation is tilted sideways; its north and south poles is positioned where most other planets would have their equators. The rings can be observed from Earth and appears to circle the planet resembling that of an archery target while the moons revolve akin the hands of a clock. Images from Voyager2 showed Uranus as a featureless planet in visible light without storms or cloud bands associated with other planets. However, other observers have noted the signs of recent increased weather activity and seasonal change as Uranus nears its equinox. The wind speed on Uranus can reach up to 900 km/h or 250 meters per second.

Uranus has a total of 27 known natural satellites. The names of these satellites were chosen and given based on Shakespeare and Alexander Pope’s works. The main satellites are known as Titania, Miranda, Ariel, Umbriel and Oberon. The satellite system of Uranus is deemed the least massive amongst the gas giants. Titania, the largest Uranian satellite has a radius of only 788.9 km which is half that of the Moon. Among all the satellites, Ariel is the youngest while Umbriel is the oldest.
The last known exploration of Uranus was in 1986 when NASA’s Voyager 2 visited the planet. It was also recorded as the only attempt to visit the planet from a short distance. Currently, no further visits are planned.

According to the astronomers first everything was an incredibly solid, heavy ball of a matter. This heavy ball exploded billion of years ago and as a result the Universe was formed. The moment of the explosion of this ball is known as “Big-Bang”. After this explosion the early universe was very small and too hot but later it got cooled and it exploded and spread out into the small pieces. Small pieces formed the basic elements called hydrogen and helium. Then the pieces join together which results object formed. Over billion of years the object becomes Galaxies, Stars and Planets. How the universe was formed is still only an idea.

A binary star is a stellar system consisting of two stars orbiting around their center of mass. For each star, the other is its companion star. Recent research suggests that a large percentage of stars are part of systems with at least two stars. Binary star systems are very important in astrophysics, because observing their mutual orbits allows their mass to be determined. The masses of many single stars can then be determined by extrapolations made from the observation of binaries. There are several subcategories of binary stars, classified by their visual properties including Eclipsing binaries, visual binaries, spectroscopic binaries and astrometric binaries.

Eclipsing Binary Stars.

Eclipsing binary stars are those whose orbits form a horizontal line from the point of observation; essentially, what the viewer sees is a double eclipse along a single plane.

Visual Binary Stars.

Visual binary stars are systems in which two separate stars are visible through a microscope that has an appropriate resolving power. These can be difficult to detect if one of the stars’ brightness is much greater, in effect blotting out the second star.

Spectroscopic binary stars.

Spectroscopic binary stars are those systems in which the stars are very close and orbiting very quickly. These systems are determined by the presence of spectral lines – lines of color that are anomalies in an otherwise continuous spectrum and are one of the only ways of determining whether a second star is present. It is possible for a binary system to be both a visual and a spectroscopic binary if the stars are far enough apart and the telescope being used is of a high enough resolution.

Astrometric Binary Stars.

Astrometric binary stars are systems in which only one star can be observed, and the other’s presence is inferred by the noticeable wobble of the first star. This wobble happens as a result of the smaller star’s slight gravitational influence on the larger star.

What is a Neutron Star.

A neutron star is a stellar remnant–a super-compressed object left over when stars with a mass between 1.4 and about 3 times the mass of our Sun exhaust their nuclear fuel and collapse inwards. The result is a condensed sphere of matter about 20 km across, with a gravitational field approximately 2 x 10^11 times stronger than that of Earth’s.

How Neutron Stars formed.

Neutron stars are formed when large stars run out of fuel and collapse inward on itself. The protons and electrons of atoms are forced together into neutrons. Since the star still has a lot of gravity, any additional material falling into the neutron star is super-accelerated by the gravity and turned into identical neutron material.

Just one teaspoon of a neutron star would have the mass of over 5 x 1012 kilograms. A neutron star actually has different layers. Astronomers think there’s an outer shell of atomic nuclei with electrons about 1 meter thick. Below this crust, you get nuclei with increasing numbers of neutrons. These would decay quickly on Earth, but the intense pressure of the gravity keeps them stable.

When neutron stars form, they maintain the momentum of the entire star, but now they’re just a few kilometers across. This causes them to spin at tremendous rates, sometimes as fast as hundreds of times a second.

Formation of Earth.

Earth is the third planet from the Sun and the fifth largest. The Planet Earth was formed 4.6 billion years ago from the same nebula cloud of gas and dust that the Sun and the eight other planets were formed.

Definition of Earth

Earth is the only planet whose English name does not derive from Greek/Roman mythology. The name derives from Old English and Germanic. There are, of course, hundreds of other names for the planet in other languages. The Earth is the only planet where life exists.

The Earth’s surface is very young. In the relatively short (by astronomical standards) period of 500,000,000 years or so erosion and tectonic processes destroy and recreate most of the Earth’s surface and thereby eliminate almost all traces of earlier geologic surface history (such as impact craters). Thus the very early history of the Earth has mostly been erased. The Earth is 4.5 to 4.6 billion years old, but the oldest known rocks are about 4 billion years old and rocks older than 3 billion years are rare. The oldest fossils of living organisms are less than 3.9 billion years old. There is no record of the critical period when life was first getting started.

71 Percent of the Earth’s surface is covered with water. The heat capacity of the oceans is also very important in keeping the Earth’s temperature relatively stable. Liquid water is also responsible for most of the erosion and weathering of the Earth’s continents, a process unique in the solar system today.

A Star can be defined as a massive and luminous ball made of Plasma. Basically, a star is formed out of cloud of cool, dense molecular gas. To become a potential star, the clouds need to collapse and increase in density.

Formation of stars can be of two ways: it can either collide with another dense molecular cloud or it can be near enough to encounter the pressure caused by a giant supernova. Several stars can be born at once with the collision of two galaxies. In both cases, heat is needed to fuel this reaction, which comes from the mutual gravity pulling all the material inward.

We can also say that a star is born from Dust and Gas that are in the same vicinity. Gravity pulls in the dust and gas until they are all together. The gravity turn up the heat due to all the close dust and gas. Then it heats up to 18 million degrees F. The Hydrogen turns to Helium and the star is born.