Indian scriptures put the number of species on the earth as about 8.4million and scientifically about 8.7 million (give or take 1.3 million) is the new, estimated total number of species-the most precise calculation ever offered - with 6.5 million species on land and 2.2 million in oceans. Announced by the Census of Marine Life, the figure is based on a new analytical technique as reported in sciencedaily.com In comparison to other species on earth, human bestowed by his intellectual power and derived by his unlimited desires to excel, empowerment, and comfort has always worked hard to find ways with so called scientifically and technologically expertise to emulate all the traits which he desired by seeing in other species on the earth e.g., swimming and flying. Man has always been fascinated more by flying in air and thanks to Wright Brothers who are generally credited with inventing, building, and flying the world's first successful airplane. Man by then has designed various types of air-planes with large passenger capacities, high speeds, long flying distances, facilities and is almost very near towards making flying cars a reality. Further, research is going on to develop flying trains. With all these flying machines available to most of the people in the world to fulfill the desire of flying in air, however, still the fascination of individual flying just like birds by human is deep rooted.
Human a species without wings is actually not made by nature to fly. Though, mankind has conquered the skies with airplanes, we have yet to match up to our winged animal counterparts who fly on their own. Scientists have determined that we never will as it is mathematically impossible for humans to fly like birds. A bird can fly because its wingspan and the wing muscle strength are in balance with its body size. It has a lightweight skeleton with hollow bones, which puts a smaller load on its wings. A bird also has air sacs connected to its lungs, which makes it even lighter and allows for easy passage of air through its lungs during flight. On the other hand, calculations of the ratio between human size and strength reveal that our species will never be able to take flight unaided. As an organism grows, its weight increases at a faster rate than its strength. Thus, an average adult male human would need a wingspan of at least 6.7 meters to fly. This calculation does not even take into account that these wings themselves would be too heavy to function. In other words, humans are not too large to fly, but our strength simply cannot support our weight in flight.
Questioning the laws of nature and going beyond these laws has been the quest of human and not of other species on earth. According to great scientist Stefan Hawking in his latest book on "Brief Answers to the Big Questions" Published by John Murray (a Hachette company)-a selection of the late cosmologist's most profound, accessible, and timely reflections from his personal archive mentioned that - "There is no God. No one created the universe and no one directs our fate,"-which also covers important existential questions such as creation of the universe, alien intelligence, space colonisation and artificial intelligence. He also said that the outcome of our life and living activities on this earth is totally governed by laws of nature. However, Indian mythology has many stories about the ability developed by people with special processes of prayers and worships to fly without wings. Great monks and spiritual people are always mentioned to travel (through air) covering long distances in no time. Though this route to flying is not a scientific understandable to common people and is thus always questionable.
Fascinated by the comic and science fiction human flying characters like superman, spiderman, batman etc. always wish to accomplish the flying in air feat. However, humans will never fly by flapping their arms with wings attached but science and technology can help human to achieve the goal of individual flying in air through small to large distances. We have already achieved one type of human-powered flight: using an aircraft with a fixed wing and propellers driven by leg pedaling. Because the wing is fixed, it can be built both long enough and light enough to permit flight. Around 100 airplanes like this have been flown to date. One notable example of this design is the Daedalus aircraft, the result of a multi-year MIT (USA) project. While never aloft again, this human-powered aircraft continues to inspire in its current efforts. In order for a human to fly without actually being in an airplane, hot air balloon, rocket, jet pack, or any other flying vehicle (real or imaginary) that person must be able to provide an upward thrust sufficient to counter his weight. Unfortunately we have no way to provide this force without some outside assistance.
Man's dream of flight is so ancient that it permeates most myths and religions. Glance at any ancient civilization's art and you'll likely find images of winged humanoids. Regardless of when humans made the first attempt, the fact remains that man has quested after the power to fly since prehistoric times. It's only in the last century that we have reached the point where we can take this technological achievement for granted. So to fly a human, one possibility is the use of a jet pack and another possibility is if we could somehow turn down the gravity. Gravity is the force of attraction with which earth is attracting every other body towards its centre. However, the technology to do so is so far beyond our current capabilities but sometime in the distant future, a relatively small portable device may allow decreasing gravity's hold on us and therefore we can leap into the air. That would be the closest to flying that a human being could ever get without being surrounded by some kind of machine that does the lifting for you, though we're not even close to knowing how to build such a device. In the last, it’s not as if the technology hasn’t shown promise, but jet propulsion has never become part of our daily lives. Fast-forward to the 2010s and jetpacks have become a reality again, if not quite in the form of the personal backpack we thought we would all be dangling from. More hopeful is the offering from Jetpack Aviation, who specializes in personal vertical takeoff and landing devices. It demoed its JB10 in Monaco (two minutes aloft) and in London in October (four minutes aloft) last year to some acclaim. We might soon be able to fly about strapped into jetpacks.