These give out a continuous spectrum of light, and thus affect a wide range of frequencies that are of interest to astronomers.
The spectrum of light that emerges from such a container will show a series of dark lines interrupting what would be a continuous rainbow.
It could vaporize a rock and identify its minerals from the spectrum of light they emitted, or drill a sample and tease apart its chemical constituents.
When we talk about telescopes, we're usually referring to devices that "see" the visual spectrum of light, but astronomers also build telescopes that gather radiation like radio waves and X rays in order to peer deep into outer space.
The spectrum of the light reflected from the planet is Doppler-shifted because the planet, like the ambulance, is moving.
Besides being tweakable to match the spectrum of a light-bulb, dye-based cells also work well in dim or diffuse light of the sort often found indoors.
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These are able to measure the spectrum of the light reflected from a cloud so accurately that Dr Rosenfeld could deduce the average size of its water droplets from the amount of light that they reflected.
Analysis of the light spectrum confirmed the blast had a redshift of 6.7.
Also, it only absorbs a sliver of the light spectrum, but the researchers are looking to other forms of the wonder element which could increase that range.
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This refraction eliminates both the red end of the spectrum (red light is not bent enough by the air layer to form part of the second image) and the blue frequencies (which are scattered away: this selective scattering is why the sky is blue).
Unfortunately, they seem to be a necessary evil in this crazy supply-versus-demand world of capitalism we all call home, particularly in light of the spectrum crunch the FCC keeps warning us about.
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Scientists have known for some time that nanowires can trap more light, and using certain materials, such as gallium arsenide, can make use of a certain section of the light spectrum that significantly increases energy production.
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This part of the infra-red spectrum, with wavelengths close to that of visible light, carries heat energy.
The city would give incentives to developers to clean up the kind of sites that fell in the light to mid-range of the pollution spectrum and thus languished in state and federal clean-up programs for their lack of severity: if developers complied with environmental guidelines and submitted to oversight, they would be spared the specter of future liability.
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That lengthens the wavelength of the light and shifts it towards the red end of the colour spectrum.
Covering around half of the universe's light spectrum, between infrared and radio waves, the new telescope should be able to detect distant planets, black holes and other intergalactic notables.
Blazars are a special case of "active galaxies" - those whose supermassive black holes spray out great quantities of light across the whole electromagnetic spectrum as they feed on surrounding matter.
These tools span much of the electromagnetic spectrum from X-rays to ultraviolet to the infrared - and of course microscopy with visible light.
Extrapolating from these results, they think that an orbiting zone plate measuring somewhere between 15 metres and 40 metres across will be enough to distinguish the spectrum of an Earthlike planet at a distance of 30 light-years.
Mr Ball next treats us to a brisk description of the human eye (remember rods and cones from school biology?), an explanation of why Newton was right and Goethe wrong about the composite character of white light, and an account of the 19th-century regimentation of the continuous colour spectrum by means of colour wheels and other classifying devices.
He has created a language of uncompromising modernist integrity that embraces an intellectual spectrum from light-heartedness to profundity.
In addition, the FCC banned the resale of this spectrum to either Verizon or ATT to prevent Light Squared from just flipping the spectrum.
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Simply put, this means choosing lights that shine down, not up, and that emit light only in those parts of the spectrum that the human eye can perceive.
Researchers at Wake Forest University recently developed a new type of light bulb that uses field-induced polymer electroluminescent technology to create a soft white, full spectrum light that could last a decade.
Current Blu-ray lasers emit light in the blue part of the electromagnetic spectrum (about 405 nm wavelength).
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For example, iron-gall ink, commonly used on ancient documents, is transparent to infra-red light and most visible in the ultraviolet region of the spectrum.
The Nicmos sees even farther than the ACS - to the most distant galaxies yet recorded - because the expanding Universe has stretched their light into the near-infrared portion of the electromagnetic spectrum.
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