Ten Most Thanked for Scientific Discoveries

Here is a list of ten most important scientific discoveries of the past century. Most of these are vital in our daily lives and are used to further advance our abilities and understand the universe. These discoveries range from medicine & physics to anthropology & archeology.

1.Vaccines

   A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe or its toxins. The agent stimulates the body's immune system to recognize the agent as foreign, destroy it, and remember it, so that the immune system can more easily recognize and destroy any of these microorganisms that it later encounters.

   Modern vaccines started more than 200 years ago when Edward Jenner developed a smallpox vaccine in 1789. This smallpox vaccine consisted of a less virulent cowpox virus that caused lesser symptoms and was generally killed by the host. Ultimately, smallpox vaccination efforts were so successful that in 1980 the World Health Organization declared the disease had been eradicated.

   The vaccines can be either used as prophylactic (to prevent infection) or as therapeutic (to help fight against a current infection). The subtypes of vaccines currently used are: killed, attenuated, toxoid, subunit, conjugate, experimental and valence.

2. Discovery of the causes of many illnesses

   During the 1800s, evidence began to mount that diseases weren't caused by foul air or spontaneous generation. Believe it or not, the idea that there might be some sort of contagion causing illness was controversial. This controversy came to a head in 1854, when a cholera outbreak hit the Soho neighborhood of London with deadly fury. In the first three days of the epidemic alone, 127 people in the neighborhood died, according to the University of California, Los Angeles, Department of Epidemiology.

   Within weeks, the death toll reached 500. But physician John Snow was on the case, interviewing families and searching for a common thread. He found it in a contaminated water pump on the corner of Broad Street. Once the pump handle was removed so that residents could no longer pump the water, the epidemic stopped in its tracks. (It would take several more years for the scientific community to fully accept that diseases are caused by germs.)

   Pathology is the study and diagnosis of disease. Pathology addresses 4 components of disease: cause/etiology, mechanisms of development (pathogenesis), structural alterations of cells (morphologic changes), and the consequences of changes (clinical manifestations).

   Today, pathologists are doctors who diagnose and characterize disease in living patients by examining biopsies or bodily fluids. In addition, pathologists interpret medical laboratory tests to help prevent illness or monitor a chronic condition. Pathologists may also conduct autopsies to investigate causes of death. Autopsy results can aid living patients by revealing a hereditary disease unknown to a patient's family.

3. Monitoring brain activity

   The skull is a tough nut to crack, which is why we're glad we can now peer inside without reaching for the circular saw. Neuroimaging, or bran scanning, is one of the newer technologies at researchers' and doctors' disposal. Researchers use computed tomography (CT or CAT scans) and magnetic resonance imaging (MRI) to get a good look at soft tissue, including the brain. 

   Neuroimaging includes the use of various techniques to either directly or indirectly image the structure, function / pharmacology of the brain. It is a relatively new discipline within medicine and neuroscience / psychology. With the advent of functional magnetic resonance imaging, or fMRI, in the 1990s researchers have been able to watch the brain in action, finding out what areas become more active during various mental tasks.

4. Microscopes

   Long before, in the hazy unrecorded past, someone picked up a piece of transparent crystal thicker in the middle than at the edges, looked through it, and discovered that it made things look larger. Someone also found that such a crystal would focus the sun's rays and set fire to a piece of parchment or cloth.

   Without microscopes, a staggering portion of our world would remain invisible. We've moved beyond (though not discarded) the optical microscopes that English scientist Robert Hooke used to discover the cell; these days, scientists can manipulate individual atoms to write words and draw pictures using scanning tunnel and atomic force microscopes.

   Even if microscopes weren't integral to the discovery of the cell - the building block of life as we know it - they belong on this list for sheer coolness. How else would we watch chromosomes replicate or marvel at the mosaic pattern of a mosquito eye?

 

5. Ancient life

   Our understanding of ancient life on Earth through fossilized remains goes back to the Greek natural historian Xenophanes, who, around 750 B.C., recognized that clam shells encased in rock in a mountainous region resembled clams from the sea. However, the field made little progress for a long period. In the 11th century, the Persian naturalist, Ibn Sina, proposed a theory of petrifying fluids. But it took a few more centuries before fossils and their relationship to past life was understood.

   What is a fossil? The answer to this question is largely a matter of what a person thinks it should be. People that work with fossils, called paleontologists, use them to obtain an understanding of ancient environments and life processes, and from this understanding can better describe the history of the earth. Thus fossils, in whatever form they appear, may be regarded as evidence of past life. Fossils may be preserved shells or bone or wood, or they may consist of material that has replaced the original organic substance, while preserving its original form. They may be the hard parts of the organism itself, or simply an impression left by the organism. Organic activity such as the footprints left by the dinosaurs or the trails of crawling insects, or burrows of worms, may be preserved in the rock and be regarded as fossils.

6. The Hubble telescope

   Hubble is one of the largest and most versatile, and is well-known as both a vital research tool and a public relations boon for astronomy. Orbiting 360 miles (579 kilometers) above Earth and weighing as much as two adult elephants, NASA's Hubble Space Telescope is a giant among giants. The telescope has completed about 93,500 trips around the planet, taking three-quarters of a million snapshots and probing 24,000 celestial objects and phenomena.

   Hubble has arguably changed our view of the universe and our place in it with achievements such as one of the first direct photos of an exoplanet. In its Deep Field Survey, the scope aimed its lens at an empty spot in the sky. With a million-second-long exposure, the survey revealed the first galaxies to emerge from the so-called "dark ages," the time shortly after the Big Bang when the first stars reheated the cold, dark universe. Hubble telescope is also used to record such magnificent images of our own Milky Way's center as the one above (A near-infrared image taken by the Hubble Space Telescope, an infrared view from the Spitzer Space Telescope, and an X-ray vision from the Chandra X-ray Observatory)

7. The Large Hadron Collider

   The Large Hadron Collider (LHC) is the world's largest and highest-energy particle accelerator. It is expected to address some of the most fundamental questions of physics, advancing the understanding of the deepest laws of nature. 

   Super-high-speed crashes that release enormous amounts of energy and could reveal exotic particles and even recreate conditions in the universe only a trillionth of a second after the Big Bang. The secrets of dark matter, the mysteries of the so-called God particle, and extra dimensions in the universe are just a few of the exotic discoveries scientists are hoping to make with the Large Hadron Collider. 

   The Large Hadron Collider gained a considerable amount of attention from outside the scientific community and its progress is followed by most popular science media. The LHC has also sparked the imaginations of authors of works of fiction, such as novels, TV series, and video games, although descriptions of what it is, how it works, and projected outcomes of the experiments are often only vaguely accurate, occasionally causing concern among the general public.

8. Sattelites

   Not so long ago, satellites were exotic, top-secret devices. They were used primarily in a military capacity, for activities such as navigation and espionage. Now they are an essential part of our daily lives. We see and recognize their use in weather reports, television transmission by DIRECTV and the DISH Network, and everyday telephone calls. 

   The first Soviet satellite (Sputnik 1) to enter Earth orbit may have struck fear in some hearts back in 1957, but the 21st-century world is now addicted to its growing fleet of communication, navigation and remote sensing satellites. GPS satellites help drivers find their way to Black Friday sales, tell smartphone users where to find the nearest Starbucks, and guide the jetliners flying millions of people around the country for Thanksgiving - even if people sometimes rely upon GPS a little too much.

9. SETI project

   Are we alone in the universe, or are there intelligent beings out there with whom we could communicate? We may never know if we rely on space travel -- distances between the stars are unimaginably vast, and our most advanced ideas for space rockets, such as light propulsion, nuclear propulsion, solar sails and matter-antimatter engines, are many years away from becoming reality.

   How can we detect signs of extraterrestrial life? One way is to basically eavesdrop on any radio communications coming from beyond Earth. Radio is not only a cheap way of communicating, but also a sign of a technological civilization. Humanity has been unintentionally announcing its presence since the 1930s by way of the radio waves and television broadcasts that travel from Earth into outer space everyday.

   The search for extraterrestrial intelligence (SETI) that officially kicked off 50 years ago has so far failed to turn up signals from little green men. But there's still much to be thankful for about the band of astronomers who listen for radio signals from star systems that could be home to aliens. Such an effort taps into a sense of trying to understand a universe that extends far beyond humanity and its existence on one rocky planet. It also forces us to consider the meaning behind our existence - are we unique, or has intelligent life stirred elsewhere?

10. Sleep variations among people

   Sleep is one of those funny things about being a human being -- you just have to do it. Have you ever wondered why? And what about the crazy dreams, like the one where a bad person is chasing you and you can't run or yell. Does that make any sense?

   In 1999, Charles Czeisler of Harvard University reported that humans' intrinsic clocks have an average day of 24 hours and 11 minutes. Of course, there is a lot of variation within the population: Some of us, with short-running clocks, rise early and are therefore called larks. Others are comfortable hummingbirds, and the rest are slower-clocked, late-rising owls. The owls among us are thankful for this explanation because it’s proof that wanting to sleep late does not make us lazy. The problem, according to Till Roenneberg, a chronobiologist at Ludwig-Maximilian-University in Munich, Germany, is that in spite of our 24/7 expectations, our society still clings to the agrarian idea of "the early bird gets the worm." 

Here's to sleeping in and still getting that worm :D

via: LiveScience , WikiPedia & HowStuffWorks