Who Is The Father Of Physics?

Physics is the field of science which studies the natural world and the laws on which it works. It is considered as the most fundamental of the sciences from which the other branches like chemistry, biology and application oriented fields like engineering and medicine originate. Physics has been studied by man since ancient times in various ways with a number of eminent personalities contributing a great deal to the field.

Physics though it employs mathematical means to comprehend various concepts which are then subjected to tests or experiments also has a philosophical aspect about it. The ancient Greek philosopher Thales (6th century BC) is widely regarded as the father of physics. He is credited with being the first to study the heavens; some of his achievements include predicting a solar eclipse, construction of an almanac and his statement that all 'things' are formed of one primary element.

Some important philosopher physicists of the period include Aristotle, Democritus and Archimedes. The father of Modern Physics is considered to be the Italian physicist Galileo Galilei most famous for his assertion of the heliocentric view of the solar system.
Some famous physicists of the modern period are Sir Isaac Newton, Johannes Kepler, Benjamin Franklin, Michael Faraday, Nikolai Tesla, Niels Bohr and Albert Einstein among others.
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World Health Organization: cell phones possibly carcinogenic

The WHO’s International Agency for Research on Cancer (IARC) previously held that cell phone radiation was not carcinogenic. That partly silenced many critics who claimed cell phone radiation was causing brain tumors and that cell phones were more dangerous than previously believed. It has since upgraded cell phone radiation to the third highest rating, below “probably carcinogenic” and “carcinogenic.”

It’s likely the WHO’s latest classification will once again ignite criticism of cell phones and debate over whether cell phone radiation can cause cancer. There are around 5 billion people currently using cell phones, according to the report by the IARC. The IARC is recommending people take pragmatic measures to reduce exposure to cell phone radiation — such as relying on texting and hands-free communication like bluetooth headsets.

The new classification indicates that there is some link between cancer and radiofrequency electromagnetic fields that are emitted by cell phones, but extensive study is still necessary. The panel found that the evidence that cell phone radiation was linked to one type of brain cancer was “limited” — and the association with any other type of cancer was “inadequate.” According to the report, the “limited” classification is just one step above the “inadequate” classification.

Mobile wireless association CTIA, one of the wireless industry’s main trade groups, refuted the WHO’s findings and said that the panel of scientists did not conduct any new research — instead it just reviewed existing studies. The classification does not mean that cell phones cause cancer and the IRAC has given the same score to other seemingly harmless substances, the association said.

The panel consisted of 31 scientists pulled from 14 different countries that reviewed two large studies that found a relationship between cell phone use and Glioma, a form of brain cancer. The scientists reviewed those studies and other scientific literature for eight days at a meeting in Lyons, France.

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X-Rays

APA

National Aeronautics and Space Administration, Science Mission Directorate. (2010). X-Rays. Retrieved March 31, 2011, from Mission:Science website:
http://missionscience.nasa.gov/ems/11_xrays.html

MLA

Science Mission Directorate. "X-Rays" Mission:Science. 2010. National Aeronautics and Space Administration. 31 Mar. 2011 http://missionscience.nasa.gov/ems/11_xrays.html

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Visualization: From Energy to Image

APA

National Aeronautics and Space Administration, Science Mission Directorate. (2010). Visualization: From Energy to Image. Retrieved March 31, 2011, from Mission:Science website:
http://missionscience.nasa.gov/ems/04_energytoimage.html

MLA

Science Mission Directorate. "Visualization: From Energy to Image" Mission:Science. 2010. National Aeronautics and Space Administration. 31 Mar. 2011 http://missionscience.nasa.gov/ems/04_energytoimage.html

HOW DO WE VISIUALIZE LIGHT WE CAN'T SEE?

False color, or representative color, is used to help scientists visualize data from wavelengths beyond the visible spectrum. Scientific instruments onboard NASA spacecraft sense regions within the electromagnetic spectrum—spectral bands. The instruments direct the electromagnetic energy onto a detector, where individual photons yield electrons related to the amount of incoming energy. The energy is now in the form of "data," which can be transmitted to Earth and processed into images.

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Infrared Waves

APA

National Aeronautics and Space Administration, Science Mission Directorate. (2010). Infrared Waves. Retrieved March 31, 2011, from Mission:Science website:
http://missionscience.nasa.gov/ems/07_infraredwaves.html

MLA

Science Mission Directorate. "Infrared Waves" Mission:Science. 2010. National Aeronautics and Space Administration. 31 Mar. 2011 http://missionscience.nasa.gov/ems/07_infraredwaves.html

INFRARED ENERGY

A remote control uses light waves just beyond the visible spectrum of light—infrared light waves—to change channels on your TV. This region of the spectrum is divided into near-, mid-, and far-infrared. The region from 8 to 15 microns (µm) is referred to by Earth scientists as thermal infrared since these wavelengths are best for studying the longwave thermal energy radiating from our planet.
A typical television remote control uses infrared energy at a wavelength around 940 nanometers. While you cannot "see" the light emitting from a remote, some digital and cell phone cameras are sensitive to that wavelength of radiation. Try it out!

Infrared lamps heat lamps often emit both visible and infrared energy at wavelengths between 500nm to 3000nm in length. They can be used to heat bathrooms or keep food warm. Heat lamps can also keep small animals and reptiles warm or even to keep eggs warm so they can hatch.

DISCOVERY OF INFRARED

In 1800, William Herschel conducted an experiment measuring the difference in temperature between the colors in the visible spectrum. He placed thermometers within each color of the visible spectrum. The results showed an increase in temperature from blue to red. When he noticed an even warmer temperature measurement just beyond the red end of the visible spectrum, Herschel had discovered infrared light!

THERMAL IMAGING

We can sense some infrared energy as heat. Some objects are so hot they also emit visible light—such as a fire does. Other objects, such as humans, are not as hot and only emit only infrared waves. Our eyes cannot see these infrared waves but instruments that can sense infrared energy—such as night-vision goggles or infrared cameras–allow us to "see" the infrared waves emitting from warm objects such as humans and animals. The temperatures for the images below are in degrees Fahrenheit.

COOL ASTRONOMY

Many objects in the universe are too cool and faint to be detected in visible light but can be detected in the infrared. Scientists are beginning to unlock the mysteries of cooler objects across the universe such as planets, cool stars, nebulae, and many more, by studying the infrared waves they emit.
The Cassini spacecraft captured this image of Saturn's aurora using infrared waves. The aurora is shown in blue, and the underlying clouds are shown in red. These aurorae are unique because they can cover the entire pole, whereas aurorae around Earth and Jupiter are typically confined by magnetic fields to rings surrounding the magnetic poles. The large and variable nature of these aurorae indicates that charged particles streaming in from the Sun are experiencing some type of magnetism above Saturn that was previously unexpected.

SEEING THROUGH DUST

Infrared waves have longer wavelengths than visible light and can pass through dense regions of gas and dust in space with less scattering and absorption. Thus, infrared energy can also reveal objects in the universe that cannot be seen in visible light using optical telescopes. The James Webb Space Telescope (JWST) has three infrared instruments to help study the origins of the universe and the formation of galaxies, stars, and planets.
When we look up at the constellation Orion, we see only the visible light. But NASA's Spitzer space telescope was able to detect nearly 2,300 planet-forming disks in the Orion nebula by sensing the infrared glow of their warm dust. Each disk has the potential to form planets and its own solar system. Credit: Thomas Megeath (Univ. Toledo) et al., JPL, Caltech, NASA
A pillar composed of gas and dust in the Carina Nebula is illuminated by the glow from nearby massive stars shown below in the visible light image from the Hubble Space Telescope. Intense radiation and fast streams of charged particles from these stars are causing new stars to form within the pillar. Most of the new stars cannot be seen in the visible-light image (left) because dense gas clouds block their light. However, when the pillar is viewed using the infrared portion of the spectrum (right), it practically disappears, revealing the baby stars behind the column of gas and dust.

MONITORING THE EARTH

To astrophysicists studying the universe, infrared sources such as planets are relatively cool compared to the energy emitted from hot stars and other celestial objects. Earth scientists study infrared as the thermal emission (or heat) from our planet. As incident solar radiation hits Earth, some of this energy is absorbed by the atmosphere and the surface, thereby warming the planet. This heat is emitted from Earth in the form of infrared radiation. Instruments onboard Earth observing satellites can sense this emitted infrared radiation and use the resulting measurements to study changes in land and sea surface temperatures.
There are other sources of heat on the Earth's surface, such as lava flows and forest fires. The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument onboard the Aqua and Terra satellites uses infrared data to monitor smoke and pinpoint sources of forest fires. This information can be essential to firefighting efforts when fire reconnaissance planes are unable to fly through the thick smoke. Infrared data can also enable scientists to distinguish flaming fires from still-smoldering burn scars.

Credit: Space Science and Engineering Center, University of Wisconsin-Madison, Richard Kohrs, designer
The global image on the right is an infrared image of the Earth taken by the GOES 6 satellite in 1986. A scientist used temperatures to determine which parts of the image were from clouds and which were land and sea. Based on these temperature differences, he colored each separately using 256 colors, giving the image a realistic appearance.
Why use the infrared to image the Earth? While it is easier to distinguish clouds from land in the visible range, there is more detail in the clouds in the infrared. This is great for studying cloud structure. For instance, note that darker clouds are warmer, while lighter clouds are cooler. Southeast of the Galapagos, just west of the coast of South America, there is a place where you can distinctly see multiple layers of clouds, with the warmer clouds at lower altitudes, closer to the ocean that's warming them.
We know, from looking at an infrared image of a cat, that many things emit infrared light. But many things also reflect infrared light, particularly near infrared light. Learn more about
REFLECTED Near-infrared radiation.

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