ScienceIQ.com

Now You See It, Now You Don't

What we call light is simply a narrow band of electromagnetic radiation that our eyes are sensitive to. This radiation enters our eyes and is conveyed to the brain by the process we call sight. While the mechanics of seeing is quite complex, the process of seeing is, in a different sense, quite extraordinary. Here are two examples. ...

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EMRadiation
Physics

Fission and Fusion

In the nuclear fission process, a heavy atomic nucleus spontaneously splits apart, releasing energy and an energetic particle, and forms two smaller atomic nuclei. While this is a normal, natural ... Continue reading

FissionandFusion
Engineering

Hollywood To The Rescue

Sixty years ago, World War II was driving many advances in the sciences; a surprising number of these developments have evolved to impact our lives today. At the beginning of the war, scientists and ... Continue reading

HollywoodRescue
Mathematics

How To Calculate The Volume Of A Right Cone

Cones are used every day for a variety of purposes. Perhaps the most useful application of the cone shape is as a funnel. For finding the volume, a cone is best viewed as a stack of circles, each one ... Continue reading

VolumeOfARight Cone
Physics

The Sound of Turbulence

Do you ever watch the water tornado that forms in a draining bathtub? Woe unto any rubber ducky floating aimlessly in the vicinity; the water's force will pull it down into the tornado. The center of ... Continue reading

TheSoundofTurbulence

Hubble & Keck Teams Find Farthest Known Galaxy in Universe

HubbleKeckAn international team of astronomers may have set a new record in discovering what is the most distant known galaxy in the universe. Located an estimated 13 billion light-years away, the object is being viewed at a time only 750 million years after the big bang, when the universe was barely 5 percent of its current age. The primeval galaxy was identified by combining the power of NASA's Hubble Space Telescope and CARA's W. M. Keck Telescopes on Mauna Kea in Hawaii. These great observatories got a boost from the added magnification of a natural 'cosmic gravitational lens' in space that further amplifies the brightness of the distant object. The newly discovered galaxy is likely to be a young galaxy shining during the end of the so-called 'Dark Ages' -- the period in cosmic history which ended with the first galaxies and quasars transforming opaque, molecular hydrogen into the transparent, ionized universe we see today.

The new galaxy was detected in a long exposure of the nearby cluster of galaxies Abell 2218, taken with the Advanced Camera for Surveys on board the Hubble Space Telescope. This cluster is so massive that the light of distant objects passing through the cluster actually bends and is amplified, much as a magnifying glass bends and magnifies objects seen through it. Such natural gravitational 'telescopes' allow astronomers to see extremely distant and faint objects that could otherwise not be seen. Analysis of a sequence of Hubble images indicate the object lies in between a redshift of 6.6 and 7.1, making it the most distant source currently known. However, long exposures in the optical and infrared taken with spectrographs on the 10-meter Keck telescopes suggest that the object has a redshift towards the upper end of this range, around redshift 7.

Redshift is a measure of how much the wavelengths of light are shifted to longer wavelengths. The greater the shift in wavelength toward the redder regions of the spectrum, the more distant the object is. The extremely faint galaxy is so far away its visible light has been stretched into infrared wavelengths, making the observations particularly difficult. Using the combination of the high resolution of Hubble and the large magnification of the cosmic lens, the astronomers estimate that this object, although very small -- only 2,000 light-years across -- is forming stars extremely actively. However, two intriguing properties of the new source are the apparent lack of the typically bright hydrogen emission line and its intense ultraviolet light which is much stronger than that seen in star-forming galaxies closer by.