Our Solar System Exploration.

Our Solar System is one of over 500 known solar systems in the entire Milky Way galaxy. The solar system came into being about 4.5 billion years ago, when a cloud of interstellar gas and dust collapsed, resulting in a solar nebula, a swirling disc of material that collided to form the solar system. The solar system is located in the Milky Way's Orion star cluster. Only 15% of stars in the galaxy host planetary systems, and one of those stars is our own Sun.

Sun:  The Sun is the star at the center of the Solar System. Age is 4.5 Billion Years,  It is a nearly perfect sphere of hot plasma,heated to incandescence by nuclear fusion reactions in its core, radiating the energy mainly as visible light and infrared radiation. It is by far the most important source of energy for life on Earth. Its diameter is about 1.39 million kilometres (864,000 miles), or 109 times that of Earth. Its mass is about 330,000 times that of Earth, and accounts for about 99.86% of the total mass of the Solar System.[20] Roughly three quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron.The Sun is travelling at 220 km per second. 

1) BIGGEST: If the Sun were as tall as a typical front door, Earth would be about the size of a nickel.

2) MOST MASSIVE: The Sun is the center of our solar system and makes up 99.8 percent of the mass of the entire solar system.

3) DIFFERENT SPINS: At the equator, the Sun spins once about every 25 days, but at its poles the Sun rotates once on its axis every 35 Earth days.

4) CAN’T STAND ON IT:  As a star, the Sun is a ball of gas (92.1 percent hydrogen and 7.8 percent helium) held together by its own gravity.

5) RINGLESS: The Sun does not have any rings.

6) NUCLEAR FUSION: The Sun's core is about 27 million degrees Fahrenheit (15 million degrees Celsius).

7) MOONLESS: But orbited by eight planets, at least five dwarf planets, tens of thousands of asteroids, and up to three trillion comets and icy bodies.

8) WHAT WE SEE:  The Sun’s visible surface sometimes has dark sunspots, which are areas of intense magnetic activity that can lead to solar explosions.

Sun Rotation Speed: The sun revolves around the center of the Milky Way Galaxy with a speed of 1.997 km/s. On the other hand, rotate means to spin on an axis. The Earth rotates every 24 hours. The sun rotates, but not at a single rate across its surface,The sun itself also rotates in a counterclockwise direction. The satellites of the planets also generally revolve and rotate in a counterclockwise direction.

(Our sun is located about two-thirds of the way out from the center of the Milky Way. (Illustration via Caltech)

How will the Sun die? 

After fusing helium in its core to carbon, the Sun will begin to collapse again, evolving into a compact white dwarf star after ejecting its outer atmosphere as a Planetary Nebula. The predicted final mass is 54.1% of the present value, most likely consisting primarily of carbon and oxygen.

While the sun may have 5 billion years left before it runs out of fuel, life on Earth will likely be wiped out long before that happens.

Revolving Around the Sun are Eight Planets : In the first Phase of the blog we will discuss Terrestrial planets: The planets Mercury, Venus, Earth, and Mars, are called terrestrial because they have a compact, rocky surface like Earth's terra firma. The terrestrial planets are the four innermost planets in the solar system.The other fours will be discussed in the 2nd phase of the blog, "The Jovian Planets".

  

 

The planets are divided into two categories, based on their composition, Terrestrial and Jovian. Terrestrial Planets including Mercury, Venus, Earth,and Mars, are primarily made of rocky material. Their surfaces are solid, they don't have ring systems, they have very few or no moons, and they are relatively small. The smallest and closest to the sun is Mercury.

Whereas , The Jovian planets are Jupiter, Saturn, Uranus, and Neptune. They orbit far from the sun. These planets have no solid surfaces and are essentially large balls of gas composed primarily of hydrogen and helium. They are much larger than the terrestrial planets.

Planet Mercury: 

Which has the shortest orbit in the solar system at about three Earth months. No evidence for life has been found on Mercury. Daytime Temperatures can reach 430 degrees Celsius (800 degrees Fahrenheit) and drop to -180 degrees Celsius (-290 degrees Fahrenheit) at night. It is unlikely life (as we know it) could survive on this planet. The inhalation of mercury vapour can produce harmful effects on the nervous, digestive and immune systems, lungs and kidneys, and may be fatal. The inorganic salts of mercury are corrosive to the skin, eyes and gastrointestinal tract, and may induce kidney toxicity if ingested. 

Inside Mercury:

Mercury Mercury is the second densest planet, after Earth. It has a large metallic core with a radius of about 1,289 miles (2,074 kilometers), about 85 percent of the planet's radius. There is evidence that it is partly molten, or liquid. Mercury's outer shell, comparable to Earth's outer shell (called the mantle and crust), is only about 400 kilometers (250 miles) thick.

Orbit and Rotation:

It speeds around the Sun every 88 days, traveling through space at nearly 29 miles (47 kilometers) per second, which is at an average speed of 105,947 miles (170,505 kilometers) per hour. faster than any other planet. Mercury spins slowly on its axis and completes one rotation every 59 Earth days. Mercury is 66.695 million km away from the Sun and 179.99 million km from Earth.

Planet Venus: is the hottest planet, with temperatures of up to 867 degrees Fahrenheit, due to an atmosphere of carbon dioxide and extensive lava flows. Nothing could live on what passes for land on Venus; its smooth volcanic plains are a scorching hellscape hot enough to melt lead, where the temperatures exceed 800 degrees Fahrenheit. High in the clouds, however, the pressures and temperatures and acidity levels would be less intense — though still vile. The distance from the Sun is 108.64 million km, and from the Earth is 257.78 million km.

Inside Venus : Venus has a rocky crust, a thick basaltic rock mantle and a nickel-iron core.There is no surface water.The surface of Venus has been mapped through its cloud layer using radar.

The surface of Venus is covered with roughly 20 percent lowland plains of solidified lava, 70 percent rolling uplands, and 10 percent highlands (volcanos, craters, mountains). The two major plains are called Aphrodite Terra Highlands (about half the size of Africa) and Ishtar Terra (a lava-filled basin which is bigger than the United States). At the surface, there are relatively slow winds. Venus does not have a very strong magnetic field; this may be because of the planet's slow rotation or perhaps Venus' core lacks a molten outer layer.

Orbit and Rotation: It takes about 243 Earth days to spin around just once. Because it's so close to the sun, a year goes by fast. It takes 225 Earth days for Venus to go all the way around the sun with a speed of 35.02 km/s.

Next to this world of fire is a world of water.

Planet Earth: The water systems on this planet help create the only known environment in the universe capable of sustaining life. The last of the terrestrial planets. Earth, our home, is the third planet from the sun. It's the only planet known to have an atmosphere containing free oxygen, oceans of water on its surface and, of course, life. Earth is the fifth largest of the planets in the solar system. It's smaller than the four gas giants — Jupiter, Saturn, Uranus and Neptune — but larger than the three other rocky planets, Mercury, Mars and Venus.

Earth happens to lie within the so-called "Goldilocks zone" around the sun, where temperatures are just right to maintain liquid water on our planet's surface.

Earth has a diameter of roughly 8,000 miles (13,000 kilometers) and is round because gravity pulls matter into a ball. But, it's not perfectly round. Earth is really an "Oblate Spheroid," because its spin causes it to be squashed at its poles and swollen at the equator.

Inside Earth:

Earth's core is about 4,400 miles (7,100 km) wide, slightly larger than half the Earth's diameter and about the same size as Mars' diameter. The outermost 1,400 miles (2,250 km) of the core are liquid, while the inner core is solid; it's about four-fifths as big as Earth's moon, at some 1,600 miles (2,600 km) in diameter. The core is responsible for the planet's magnetic field, which helps to deflect harmful charged Particles Shot from the sun.

Above the core is Earth's mantle, which is about 1,800 miles (2,900 km) thick. The mantle is not completely stiff but can flow slowly. Earth's crust floats on the mantle much as a piece of wood floats on water. The slow motion of rock in the mantle shuffles continents around and causes earthquakes, volcanoes and the formation of mountain ranges.

Orbit and Rotation: 

The earth rotates once every 23 hours, 56 minutes and 4.09053 seconds, called the sidereal period, and its circumference is roughly 40,075 kilometers. Thus, the surface of the earth at the equator moves at a speed of 460 meters per second--or roughly 1,000 miles per hour.

The earth is moving about our sun in a very nearly circular orbit. It covers this route at a speed of nearly 30 kilometers per second, or 67,000 miles per hour. In addition, our solar system--Earth and all--whirls around the center of our galaxy at some 220 kilometers per second, or 490,000 miles per hour. As we consider increasingly large size scales, the speeds involved become absolutely huge!

Planet Mars:  Might have also supported life about 3.7 billion years ago, when the planet had a watery surface, and moist atmosphere. Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, being larger than only Mercury. In English, Mars carries the name of the Roman god of war and is often referred to as the "Red Planet". its Gravity: 3.711 m/s² , Distance from Sun: 227.9 million km and 

Radius: 3,389.5 km. Beyond the four Terrestrial planets of the inner solar system lie the Jovian planets of the outer solar system. Mars has only a thin atmosphere, with a surface pressure less than a hundredth of the Earth's. Even worse, it is 96% carbon dioxide with only about 0.1% oxygen, An astronaut on Mars would not be able to breathe the Martian air and would need a spacesuit with oxygen to work outdoors.

Inside Mars:  Its surface is covered with deep canyons and huge, inactive volcanoes. The soil on Mars contains a substance called iron oxide, which gives the planet a red color. Like Earth, Mars also has a core, mantle, and crust. Mars is lighter for its size than the other rocky planets.The planet’s crust might be made of three layers. This is the first time scientists have directly probed the inside of a planet other than Earth, and will help researchers to unravel how Mars formed and evolved over time. Before this mission, researchers had measured only the interior structures of Earth and the Moon. “This information was missing, until now, from Mars,”

Orbit and Rotation:

Mars has an orbit with a semimajor axis of (228 million km), and an eccentricity of 0.0934. The planet orbits the Sun in 687 days and travels making the average orbital speed 24 km/s, around the Sun. (53,853 miles per hour), or a period of about 686.93 days.

till now i have discussed about four planets in detail , the next four (Jovian planets) will be explore like above in the 2nd phase of the blog. i hope that you will enjoy by readiing it , your precious comments will be higly appericiated.

to be continued .......................

Regards

Tahir Ahmad Dawood

The Most Destructive Pandemics and Epidemics In Human History

An epidemic is a disease that can be spread from person to person and affects many individuals all at the same time in a location where the disease is not permanently prevalent. 

A pandemic is like an epidemic, but is much larger in scale. Pandemics can affect whole countries, continents, and sometimes even the entire world.

Today, we're going to take a look at the most destructive epidemics and pandemics in human history. 

After that, we'd be grateful if you'd leave a comment and let us know what unsettling historical topics you would like to read about. OK.

Ready to read  some scary stuff? , Remember, we did warn you.

The Plague Of Athens:

Striking at about 430 BCE during the Peloponnesian War, the Plague of Athens took out somewhere in the area of 100,000 people within a three year period.  If that doesn't sound too impressive, keep in mind that's a full 25% of the entire Athenian population of the day. In order to help others later identify it, the Athenian General and historian Thucydides

Thucydides

recorded his own eyewitness account of the plague and its symptoms. He described his sickness as presenting with a high fever, diarrhea, and a pustular rash. Equally disturbing is Thucydides' description of the social effects of the epidemic. He claimed that a widespread belief the plague could not be survived caused people to start behaving like criminals and mobs. He wrote, "The catastrophe was so overwhelming that men, not knowing what would happen next to them, became indifferent to every rule of religion or law." Also known as the Plague of Galen,

The Antonine Plague: 

The Antonine Plague

Ravaged the Roman Empire from 165 to 180 CE. While the nature of the plague isn't known today, it's believed that it might have been an outbreak of measles or smallpox. Whatever the case, historians think it was likely brought to Rome by troops returning from war. At its most deadly, the Antonine Plague was killing a full quarter of all who became infected by it. In the end, it is believed to have killed roughly 60 million people. And it wasn't just the poor and needy who suffered. The list of the dead is believed to have included. Lucius Verus, a Roman emperor.                                           

Lucius Verus

The Plague Of Cyprian:

                                 

The Plague Of Cyprian

From about 249 to 262 CE, the Roman Empire was afflicted by an epidemic that eventually came to be known as the Plague of Cyprian, in honor of the early Christian saint and writer who recorded the event. Contemporary accounts suggest the symptoms included vomiting, bloodshot eyes, loss of hearing, blindness, and loss of coordination. Historians don't agree on which disease was behind the plague, but candidates include smallpox, some type of flu, or a strain of the Ebola virus. It is believed that the epidemic at its worst, was killing 5,000 people a day in Rome. In the aftermath, the empire faced some of its most difficult years and very  nearly collapsed. The Plague of Justinian infected the Byzantine Empire around 541 CE 

 Byzantine Empire 

and is considered one of the first recorded pandemics. You may want to check out some of our other blog about it. At its peak, this plague killed roughly 10,000 people a day and ultimately took the lives of roughly 100 million people around the world. While many suspected the Plague of Justinian originated in China or India and was then spread through sea trading routes, the particular virus or disease that caused the pandemic was never identified. It lasted 225 years before it finally disappeared. And it managed to alter the course of human political history by preventing the Byzantine Empire from spreading into Italy. 

Smallpox is the name for a highly contagious disease that is caused by variola virus. Though no one knows how smallpox came into existence or how it spread so fast, the earliest known cases come from Egypt and India. The oldest known evidence for smallpox actually comes from the mummy of the Egyptian Pharaoh Ramses V. Ramses died in 1145 BCE. 

 Ramses V

And his remains show signs of the same pockmarks that are associated with this particular disease. Smallpox epidemics are believed to have killed massive numbers of people during the Middle Ages and within the Roman Empire. It was eventually introduced to the Western hemisphere in the 17th century. Brought by European explorers and settlers, it led directly to the deaths of millions of people native to North, South, and Central America. It is also believed to have decimated the populations of the Aztec and Inca civilizations. As if all that's not frightening enough, the Japanese smallpox epidemic, which lasted only from 735 to 737 CE, killed off approximately one-third of the entire population of Japan.

Malaria is an infectious disease caused by a parasite found in mosquitoes that infects as many as 200 million people every year. Highly resistant to drugs, it is one of the most consistently deadly pandemics in human history. Spread principally through those same mosquitoes, malaria typically impacts less developed countries. Though scientists didn't understand it or how it was spread until the 1800s, this particular epidemic has been around a while. Documented descriptions that match the symptoms of malaria date all the way back to 2700 BCE. Some even believe it may have been responsible for the demise of Genghis Khan. 

Genghis Khan.

Black Death: is the colloquial name for the bubonic plague, which ravaged Europe's population throughout most of the 1300s. It is the most notorious pandemic in human history. Caused by a bacteria called "Yersinia pestis," which is highly deadly to humans, the plague was spread by fleas who were themselves immune to it. The fleas would latch onto rats, who were spread by merchant ships moving from Asia to Europe. The Black Plague is characterized by oozing, bleeding sores and high fevers. During the 14th century, it is thought to have killed somewhere in the neighborhood of 50 million people throughout Asia, Africa, and Europe. In fact, it is believed 30% to 60% of Europe's total population was completely wiped out. It was also persistent. Various forms of the plague continued to spring up and become a recurring threat for the next century or so. Each time it reappeared, it claimed even more lives. 

The Cocoliztli Epidemic:

Also known as the "Great Pestilence," was an incident that occurred from 1545 to 1548 in what is today Mexico. A mysterious illness or illnesses, characterized by high fevers and bleeding, swept through the Mexican highlands. While the identity of the sickness is still unknown, some modern researchers suspect a strain of salmonella called "Paratyphi C" might have been the initial cause. Today, estimates for the death toll range from five to 15 million people, making it the deadliest epidemic in Mexican history.

The Moscow Plague:

the Moscow Plague

Another outbreak of the bubonic plague, the Moscow Plague, killed 50,000 to 100,000 people in 1770. There is no exact figure. But it is believed this outbreak killed about one-third of Moscow's population at the time. Before all was said and done, the city experienced food shortages and intense rioting. If there is a silver lining, it's that after this reappearance in Moscow, the bubonic plague essentially disappeared from Europe in the 18th century.

The Spanish flu:

The pandemic that has come to be called the "Spanish flu" started in 1918 and would go on to infect an entire third of the world's population. Estimates on the death rate vary. But this particular sickness is believed to have affected roughly 500 million people and taken the lives of between 20 and 50 million people worldwide in just two years. Scientists would later identify the Spanish flu as a particularly brutal flu strain called "H1N1."The so-called Spanish flu also serves as a warning about what can be concluded from the name given to a pandemic. Scientists are unsure of where in the Spanish flu originated. France, China, and Britain have all been suggested as a potential birthplace of the virus, and so has the United States, where the first known case was reported at a military base in Kansas on March 11, 1918. So why is it called the Spanish flu? Well, though it was one of the most ruthless pandemics in history, it struck during World War I. And most of its destruction wasn't reported on at the time because of censorship. Spain, however, was a neutral country during the war and its newspapers were the only ones to cover the pandemic. This led to the misnomer "Spanish flu," which has caused some people to falsely believe the disease originated in Spain.

The Hunderd Year 3rd Pandemic:

The third pandemic was an outbreak of the bubonic plague that originated in China and lasted from 1855 to the 1950s. Yes, this outbreak actually lasted almost 100 full years. The pandemic slowly spread beyond Asia to other continents and is believed to ultimately have taken the lives of as many as 15 million people. It wasn't until 1898 that Paul-Louis Simond discovered the cause of the disease was brown rats and rat fleas. This discovery, the first time a scientist had conclusively demonstrated what caused the plague, helped curb the spread of the sickness and eventually led to the creation of a vaccine.

The Swine flu Pandemic:

The Swine flu Pandemic

lasted from 2009 to 2010 and is believed to have killed over 200,000 people worldwide. Rooted in a unique influenza virus that had never previously been identified in animals or humans, it posed a huge problem for scientists. The closest related flus were the North American swine, H1N1, virus and the Eurasian swine, H1N1, virus. But investigations quickly showed that most of the people infected had never been exposed to pigs.This made it clear that the new virus was only affecting humans. At the time, the 2009 H1N1 was considered one of the most deadly modern pandemics and served as a warning about how incredibly vulnerable we humans still are to influenza strains. 

The 2014 Ebola Outbreak:

The 2014 Ebola outbreak

Was the largest known breakout of Ebola in history and constituted the first actual Ebola epidemic. This outbreak, which would last roughly two years, would prove especially destructive to the people of West Africa. Finally, in March 2016, the World Health Organization determined that the situation was under control. Sadly, this was long after at least 28,616 cases had been confirmed and at least 11,310 deaths had occurred throughout Liberia, Guinea, and Sierra Leone.

HID/AIDS: 

Acquired Immune Deficiency Syndrome, more widely known by the acronym AIDS, has caused the deaths of millions of people. Scientists believe the disease originated in Africa during the 1920s and spread slowly from there. By 1981, a case had been reported in Los Angeles, California. The emergence of the disease had deep and lasting effects on American culture. On the upside, safe sex and the use of condoms became far more common. On the downside, in addition to the lives lost,

the epidemic triggered waves of bigotry that were directed at the LGBT community. The virus form of AIDS, known as "HIV," attacks the immune system. A person infected with HIV can contract AIDS when their body becomes too weak to fight off infections. However, not all of those who are infected with HIV will get AIDS. Many with the virus are able to live normal, healthy lives, thanks to antiretroviral treatments which have become more widely available over the years. However, not everyone was so lucky. According to the World Health Organization, since the beginning of the epidemic, 75 million people have become infected with HIV, and about 32 million have died from it. So what do you think? 

Which of these historical plagues would scare you the most? Let us know in the comments below.

Regards.

Tahir Ahmad Dawood