Tools of the Astronomer
Formation of the Universe: Big Bang Theory
The Big Bang Theory. The topic everyone has heard about, but no one is quite sure what it is. Astronomers describe the Big Bang Theory as the general process of how the universe began, about 13.8 million years ago. They believe, and research has proven, that the universe began as one single point. This single point was an accumulation of every speck of energy found in the cosmos/universe, jammed into one point. This combined point of energy exploded with an extreme amount of force; this force ended up creating matter. The matter created propelled outwards which created the millions of galaxies in our universe, such as the Milky Way.
Formation of Planets
All planets, in our solar system, were created inside the Milky Way galaxy approximately 4.5 billion years ago when gravity pulled and combined anomalies together. Gravity collapses certain materials within each other and formulates them to spin, forming the sun in the center of the nebula. Other planets outside of the Milky Way are thought to have formed via “the solar nebula”; a disc-shaped cloud of gas and dust produced from leftovers from the Sun’s formation. The most recent method accepted, by scientists and others, would be planets formed through the method of accretion. This would define the plants beginning as a small speck of dust in an orbit around the central protostar. The inner domains of the Solar Systems would be far too warm for certain molecules like water and methane to condense. Planetesimals (minute planets) can only be formed from metal compounds with high melting points (i.e iron, nickel, aluminium, or rocky silicates). These certain bodies of compounds can become terrestrial planets (Mercury, Venus, Earth, and Mars).
During the formation of these planets, they were encased in a disk of gas and dust. The gas mitigated the speed of planet orbit as gas was moderately supported by pressure. This resulted in drag and gravitational interaction which caused certain planets to migrate into new orbits. The density and temperature within the immersed discs was the main factor in rate of migration.
Certain planets with lower temperatures (i.e Jupiter, Saturn, Uranus, and Neptune), were formed further away from the sun and beyond the frost line (a point between the orbits of Mars and Jupiter). The ice which was produced here was cool enough for their compounds to remain solid. They were much more abundant than high melting point compounds such as metals and silicates. This advantage allowed giant planets to grow further and later capture gases such as hydrogen and helium (hence the name gas giants).
These written theories all add up to our planets being originally formed in/near their current orbits. This hypothesis is in the process of being theorized again. As wikipedia states “Currently, many planetary scientists think that the Solar System might have looked very different after its initial formation: several objects at least as massive as Mercury were present in the inner Solar System, the outer Solar System was much more compact than it is now, and the Kuiper belt was much closer to the Sun”. The Kuiper belt is a ring-like form consisting of icy bodies and is located outside of Neptune’s orbit. Pluto is the most well known object located on/in the Kuiper Belt.
Our Solar System: The Milky Way
The Milky Way is the galaxy that contains our Solar System. There are eight most well known planets in our solar system; Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. These are the planets that we have heard the most of, and are the most popular ones as well.
The Milky Way: Our Planets
Mercury is the closest planet to the Sun, and the smallest planet in our solar system. Mercury is a rocky planet, meaning, it has a cratered and rocky planet. It is mainly composed of silicate rocks and metals. Mercury is one of the planets that has a very thin exosphere. It’s atmosphere is mainly composed of helium, oxygen, sodium, and potassium. Life on Merury has no potential because it’s environment can reach up to -290 degrees Fahrenheit. Mercury has extremely cold temperatures, which is simply ironic because it is extremely close to the Sun.
Venus is the second closest planet to the Sun in our solar system. Venus has often been called Earth’s twin due to its similarity in structure and size. Venus’s exosphere, unlike Mercury, is very thick and toxic. It is filled with carbon dioxide and sulfuric acid. However, it’s environmental atmosphere is quite different; Venus’s solid surface is highly reactive and volcanic. Many scientists have stated and believed that there were signs of water on Venus. Future explorers will try to confirm if there were signs of an ancient ocean on this planet. Venus has extreme and acidic temperatures, and it has very high wind speed.
Mars is the fourth planet from the Sun in our solar system. Mars has a very thin atmosphere, and it’s environment is cold, dusty, and desert-like. Mars is a rocky planet, meaning it has a solid surface with alterations of volcanoes, high impact wins, and crustal movements. The possibility of finding life on Mars is little to none because of it’s harsh environmental features and exosphere.
Jupiter is the fifth and largest planet in our solar system. Jupiter’s exterior features are beige-brown stripes and swirls. Jupiter is a gas giant planet, meaning it is mostly composed of helium and hydrogen. Thus, it does not have a true surface. Jupiter’s atmospheric environment is strong levels of gravity, high pressure, and strong winds. Due to these reasons, it is hard for forms of life to have either peace and quiet, longevity, or a life span.
Saturn is the sixth planet and second largest planet in our solar system. Saturn, out of all the other planets, is the one with the most unique features; Saturn has orbital rings that surrounds it. Like Jupiter, Saturn is also a gas giant planet. Saturn’s atmospheric environment, like Jupiter, consists of strong levels of gravity, high pressure, and strong winds. Thus, productions of forms of life and longevity will be and are already rare on this planet.
Uranus is the seventh planet from the Sun in our solar system. Uranus, in fact, was discovered in 1781 and was the first planet to be discovered by humans. Uranus is known as the “sideways” planet because it rotates on it’s side. Uranus is an ice giant planet, meaning, unlike Jupiter and Saturn, the atmospheric environment is mainly composed of rocky and icy cores rather than helium and hydrogen, which are gases.
Neptune is the eight planet from the Sun in our solar system. It’s exterior features are white and light blue. Neptune is our solar systems’ windiest planet. It’s atmospheric environment consists of high winds. Neptune, like Uranus, is an ice giant planet, meaning, another feature of this planet is rocky and icy cores, and a composition of water, methane, and ammonia.
Fun Facts: Big Bang Theory
1. Einstein first stated this theory as abominable and insane. Georges LeMaître, a Belge priest and scientist, first suggested the idea that the universe is very large and could still be expanding. When he wrote his theory to Einstein, Einstein wrote back, “your physic calculations make absolutely no sense!”
2. The idea of the Big Bang Theory has been around since 1922, however, it has been dismissed by many physicians and scientists for countless decades.
3. The term, “Big Bang Theory”, came from Fred Hoyle, an English astronomer. He once said in an interview, “it was a huge and vast explosion, and [it’s] expansion is a relic of violence.” Hence the name Big (huge and vast explosion) Bang (relic of violence).