DANGERS AWAITING HUMANITY ON EARTH

     DANGERS AWAITING HUMANITY ON EARTH

(Some guidance is taken from Times of India news paper dated 27-10-2015 of Hyderabad, India)

Ever since the formation of the planet Earth it is subjected to many impacts by space debris such as asteroids etc. It is also understood that the Earth when it was in a molten state was collided by another mass of its own size and as a result the two merged and the loose debris was scattered into space to form Moon. Earth is usually hit by an asteroid in every few hundred thousand years, sufficient to cause great damage to Earth and life on Earth.

     Modern world started about 10000 years ago, and research on the probable dangers to Earth is well established. I have already discussed about some dangers to Earth and life on Earth. Still there are many more dangers to be discussed. Hence I like to give a brief summary of all such dangers in this post.

DANGER FROM ROBOTS:

Artificial intelligence in robots is increasing rapidly. It is also feared that killer robots are being developed by some countries so that they may be used in war. These robots are capable of thinking and acting and acting on their own accord. United Nations recently called for a ban on development of killer robots. Inventor Elon Musk is also of the opinion that artificial intelligence might be the greatest existential threat to humanity. The world famous physicist Stephen Hawking said “The development of full artificial intelligence could spell the end of the human race. Humans who are limited by slow biological evolution, could not compete, and would be superseded.”

DANGER FROM GAMMA RAY FLASHES:  

Gamma ray flashes are caused by the merging of two collapsed stars. The energy liberated in these explosions is many times the energy of Sun. Though these flashes are many they are happening in the distant galaxies very far away. If this happens nearer to our solar system, the ozone layer of Earth which is protecting us so far gets destroyed, causing heavy damage to life on Earth. It is difficult to detect double stars and hence the danger cannot be ascertained in advance. Hence the danger can strike any moment either earlier or far away in time.

DANGER FROM MAGNETIC REVERSAL:

It is observed that the Earth’s magnetic pole reversals occur at some intervals. In the last million years there are about 170 magnetic reversals on Earth, at an average period of about 588000 years of interval. The last reversal occurred about 781,000 years ago . Hence the next magnetic reversal is likely in the near future. In this process of magnetic reversal, the magnetic field dwindles to nothing, and then over a century gradually reappears with the north and south poles flipped. The latest observation by the European Space Agency (E S A) indicates that the Earth’s magnetic field is weakening at a faster rate and is likely to flip within the next 100 years. In the absence of strong magnetic field of Earth, the cosmic rays from the Sun and other energetic particles from space are likely to damage ozone layer, resulting destruction to life on Earth.

DANGER FROM BLACK HOLES:

A black hole is a body that has a strong gravitational field to prevent even light escaping from its gravity. Most galaxies have super massive black holes as massive as several million Suns, at the centre. Even our galaxy, the Milky Way is full of black holes at its centre. In July 2015, scientists from Durham University discovered five previously unidentified super massive black holes, billions of times the size of our Sun, increasing fears that one could come closer to Earth than previously anticipated. In some others opinion, one such black hole passing nearby could eject Earth from the Solar system and send us hurtling into deep space. But in my view this may not be a possibility since the Solar system is nearer to the edge of our galaxy, whereas the black holes are nearer to the centre of galaxy.

DANGER FROM ALIEN INVASION:

The universe is vast and our planet is only a speck when compared to the present size of the universe. There is intelligent life on our planet. Our planet is revolving around the star, Sun. Many such habitable planets were discovered revolving around other stars. It is quite possible that a more intelligent life than on Earth may exist there. Ours is carbon based life. Silicon has similar properties to form silicon based life. Or there may be some other element not existing on Earth to form life on exoplanets. If aliens come visit Earth can we expect them to be friendly with us or they may act as our enemies is a matter to be considered. Stephen Hawking thinks it more likely that such creatures would come to Earth in search of resources and bent on our destruction. Other cosmologists even support that extraterrestrial invaders might plunder a vital natural resource, such as the water from our ocean, bring with them pests with a taste for human flesh or upset our planet or solar system causing Earth’s destruction.

DANGER DUE TO ERUPTION OF SUPER VOLCANOES:

One of the major dangers to earth from the Earth itself is from the eruption of super volcanoes. About 252 million years ago an eruption of super volcano in Siberia wiped out about 95% of all Earth’s species. A super volcano is discovered under yellow stone National Park in Wyoming in America. It erupts at the interval of about 600,000 years. The last eruption took place about 640,000 years ago. Scientists have discovered that the ground in yellow stone Park is 74 cms. Higher than it was in 1923, indicating a massive swelling underneath the Park. If it explodes within minutes tens of thousands would be dead and the long term effects would be more devastating. Such eruptions would result in planet wide cloud of debris in atmosphere, obstructing sun light, destroying plant and animal life on Earth, besides considerable loss in human life. Also temperatures would go down by 21 degrees, rain would turn to acid.

DANGER FROM ASTEROID IMPACT:

Beyond the orbit of planet Mars, there is asteroid belt. The largest of the asteroids in this belt, Ceres in only of 600 miles in diameter. Some asteroids, such as Hermes cross the orbit of Earth and are known as Potentially Hazardous Asteroids (P H As). Future collisions with Earth cannot be ruled out. A collision of asteroid of one mile in diameter is enough to wipe out civilization on Earth, and such impact is possible once in million years or less, according to experts. It is believed that the dinosaurs were wiped by a six mile wide asteroid impact about 65 million years ago. The path of the asteroids is constantly watched by astronomers. There are plans to divert the path of any dangerous asteroid by using nuclear weapons, but it is doubtful whether a large sized asteroid can be diverted by this process. There seems to be no danger from the asteroid impact in the near future. It has been more than a century since the large major asteroid  impact took place in a remote and uninhabited region of Siberia. It was powerful enough to fell trees in an area of 800 square miles (2000 square kilometers). An asteroid known as Apophis which is 984 feet (300 metres) across will pass much closer to Earth than Moon, within the orbits of geostationary satellites only 22,236 miles (35785 kilometres) above the surface of the Earth, on Friday 13^th April 2029, but without any collision with Earth. Earth's gravitational pull may change its orbit, but nobody knows the likely changed orbit.

DANGER FROM GLOBAL WARMING:

Global warming is the increase in Earth’s surface temperature due to effect of green house gases such as carbon dioxide emissions by burning fossil fuels, or from deforestation which trap heat that would otherwise escape from Earth. We will soon see carbon dioxide concentration that have not been reached on Earth for the past 50 million years. There is a total worldwide emission of carbon dioxide of 22 billion tons to the atmosphere each year. About a third of it comes from electricity generation and another third from transportation and a third from all other sources. The concentration of carbon dioxide has increased by 60 times than it was in 1860. A rise of 2 to 3 degrees of celsius of temperature in the polar region would have serious effect, where it would cause the glaciers to melt. This can cause the rise in ocean levels by about 250 feet (75 metres). 50% of world population is in coastal areas.   They will become homeless. Cities like London, Newyork, Losangeles, Sydney, Tokyo, Hongkong, Bombay and Rio De Janeiro etc. are likely to be submerged in ocean water. There are attempts to control global warming, but how far it will be successful we have to wait and see.

DANGER FROM WORLD WAR III: (Please go through my post on world war iii for details).

Many scientists believe in the possibility of world war at any time. Most of the countries have developed biological and chemical weapons as well as devastating nuclear weapons. Besides this they are even training robots to take part in world war for accurate bombing at a desired place. Currently 9 countries are known to have nuclear capabilities. In 2006 the physics Today journal concluded that the detonation of 100 nuclear bombs (which is only a negligible fraction of the total number of available nuclear weapons) would bring about a “nuclear winter” causing temperatures to drop to the lowest in 1000 years and “likely eliminate the majority of the human population.” Even there is danger to humanity if the biological weapons are used in the war. If anthrax was released into the air, it could cause fatalities in 90% of the population exposed to it. There is astrological tendency that the world war iii is likely to start in the year 2026 as a biological war and is likely to turn into nuclear war. The war seems to cover many years and most of the world population are likely to suffer heavily.

DANGER DUE TO PANDEMICS:

Throughout history many deadly pathogens have emerged which have wreaked havoc on the human race. The Black Plague killed one in every four Europeans in the 14^th century while in just two years the 1918 Spanish flu took at least 50 million lives.

Recent possible pandemics including SARS, bird flu and MERS, a corona virus which originated in Saudi Arabia, have eventually died down, but experts say that it is only a matter of time before one goes global. If nature was not enough to worry about, scientists have been accused of engineering mutant versions of diseases, which, if they escaped from the lab, could threaten the future of humanity.

Last year after researchers at the Wisconsin-Madison created a life threatening virus that closely resembled the 1918 Spanish flu, many disease experts were appalled. Simon Wain-Hobson a virologist at the Pasteur Institute in Paris, said: “It is madness, folly. If society, the intelligent lay person understood what was going on, they would say, “What are you doing?”