Sun: Heart of the Solar System | Abdullah Al Moinee

Abdullah Al Moinee

[ www.daily-sun.com/magazine/details/118153/Sun:-Heart-of-The-Solar-System ]

The universe is everything that exists from the smallest particle on earth to the vast galaxies of deep space. We are the way for the cosmos to know itself. We know we are approaching the greatest of mysteries. Mystery creates wonder and wonder is the basis of man's desire to know which opens the threshold of curiosities in the vastness of the universe. The conquest of the solar system is not only a one small step for man but also one giant leap for mankind.

The sun lies at the heart of the solar system, where it is by far the largest object. It holds 99.8 percent of the solar system's mass and is roughly 109 times the diameter of the Earth — about one million Earths could fit inside the sun. The sun is orbited by eight major planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and a dwarf planet called Pluto.

In the sixteenth century, Nicholas Copernicus argued that it was the Earth that traveled around the sun. However, Copernicus’s view of the solar system wasn’t accepted for many years until Newton formulated his laws of motion. The Greek philosopher Aristarchus is credited as being the first person to claim that the Earth orbited the sun. Egyptian, Indo-European, and Meso-American cultures all had sun-worship religions. In the Aztec religion, extensive human sacrifice was demanded by the sun gods Huitzilopochtli and Tezcatlipoca. In Japan, the sun goddess, Amaterasu, played an important role in ancient mythology and was considered to be the supreme ruler of the world. The characters which make up Japan’s name mean “sun origin” and its flag depicts the rising sun. In Libya, both male and female mummies have been discovered with tattoos symbolizing sun worship. Sun does have another common name: Sol. This name originates from the ancient Roman’s god of the Sun, Sol.

The sun was born about 4.6 billion years ago. Many scientists think the sun and the rest of the solar system formed from a giant, rotating cloud of gas and dust known as the solar nebula. As the nebula collapsed because of its gravity, it spun faster and flattened into a disk. Most of the material was pulled toward the center to form the sun. The sun has enough nuclear fuel to stay much as it is now for another 5 billion years. After that, it will swell to become a red giant. Eventually, it will shed its outer layers, and the remaining core will collapse to become a white dwarf. Slowly, this will fade, to enter its final phase as a dim, cool theoretical object sometimes known as a black dwarf.

The sun is just one of about 100 billion stars in our galaxy. It has a diameter of 1,390,000 km. Its core temperature is 15 million º C. Its surface temperature is 5,500 ºc. Cooler (3,800 ºc) surface areas are called sun spots. It is the largest object in the solar system and makes up 99.8% of the total mass of the Solar System. Approximately 109 planet Earths would fit on the surface of the sun and more than one million planet Earths would fit inside of the sun. At around 1,392,000 kilometres (865,000 miles) wide, the Sun’s diameter is about 110 times wider than Earth’s. The sun is the closest star to Earth and is 149.60 million kilometers (92.96 million miles) away. The sun rotates on its axis once in every 25.38 Earth days or 609.12 hours in the opposite direction to Earth from west to east. A person weighing 150 pounds on Earth would weigh 4,200 pounds on the sun because the sun’s gravity is 28 times that of Earth. It orbits some 25,000 light-years from the galactic core, completing a revolution once in every 250 million years or so.

One of the most obvious signs that the Sun is not just sitting there is its rotation with Solar flares are jets of particles that burst from the sun and can disrupt satellite communications and knock out electricity on Earth. Around 74% of the Sun’s mass is made up of hydrogen. Helium makes up around 24% while heavier elements such as oxygen, carbon, iron and neon make up the remaining percentage.

The energy output of the Sun is about 386 billion megawatts and is produced by nuclear fusion, using Hydrogen as fuel. Apart from Heat and Light, the Sun also emits a stream of charged particles called the Solar Wind. These are ejections of plasma (extremely hot charged particles) that originate in the layer of the Sun known as the corona and they can travel through the solar system at up to 450 km per second. The atmosphere of the Sun is composed of three layers: the photosphere, the chromosphere, and the corona. The Solar Wind causes Radio Interference at certain times and causes the characteristic Tails of Comets along with alters the trajectory of spacecraft. Moreover it produces the Aurora Borealis and the Aurora Australis are caused by the interaction of solar winds with Earth’s atmosphere. An aurora, sometimes referred to as a polar light, is a natural light display in the sky, predominantly seen in the high latitude (Arctic and Antarctic) regions. When magnetic energy is released by the Sun during magnetic storms, solar flares occur which we see on Earth as sunspots. Sunspots are dark areas on the Sun’s surface caused by magnetic variations. A solar eclipse occurs when the Moon is between the Sun and the Earth. A solar eclipse is a type of eclipse that occurs when the Moon passes between the Sun and Earth, and the Moon fully or partially blocks ("occults") the Sun. This can happen only at new moon, when the Sun and the Moon are in conjunction as seen from Earth in an alignment referred to as syzygy.

Solar Probe Plus is an exciting mission of exploration and discovery, a journey to the Sun itself. The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland is designing and will build the Solar Probe Plus spacecraft for NASA, scheduled to be launched no later than in 2018. This mission will transform our understanding of the Sun and its sister Sun-like stars and will enable further exploration.

We make our world significant by the courage of our questions and by the depth of our answers. All our dreams come true if we have enough courage to pursue them. Man must rise above the Earth to the top of the atmosphere as somewhere something incredible is waiting to be known. The Sun has originated curiosities throughout the ages. Although a certain amount of information was ascertained about the sun before the space age, this new era has revealed many secrets barely imaginable before that time.

Moinee, A. Al. “Sun: Heart of the Solar System” The Daily Sun. 6(131). 4 Mar. 2016. Morning Tea. 6(10).