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GRB 970228 [ 4 ] was the first gamma-ray burst (GRB) for which an afterglow was observed. [ 5 ] It was detected on 28 February 1997 at 02:58 UTC . Since 1993, physicists had predicted GRBs to be followed by a lower-energy afterglow (in wavelengths such as radio waves , x-rays , and even visible light ), but until this event, GRBs had only been observed in highly luminous bursts of high-energy gamma rays (the most energetic form of electromagnetic radiation ). The burst had multiple peaks in its light curve and lasted approximately 80 seconds. Peculiarities in the light curve of GRB 970228 suggested that a supernova may have occurred as well. The position of the burst coincided with a galaxy about 8.1 billion light-years [ 3 ] away (a redshift of z = 0.695), providing early evidence that GRBs occur well beyond the Milky Way . [ edit ] Observations
GRB 970228
Oxygen! Its Evolution on Earth
Scientists are getting closer to unlocking the secrets of oxygenation of the Earth's biosphere -its oceans and atmosphere- with new research shows that shows that organisms like vascular plants may have appeared and evolved under lower oxygen conditions than previously thought. Ariel Anbar, Arizona State biogeochemist, and an international team of scientists, using pioneering techniques at Arizona State University, have found that the appearance of large predatory fish as well as vascular plants approximately 400 million years ago coincided with an increase in oxygen, to levels comparable to those we experience today. If so, then animals from before that time appeared and evolved under markedly lower oxygen conditions than previously thought. "There has been a lot of speculation over the years about whether or not oxygen in the atmosphere was steady or variable over the last 500 million years," explained Anbar, who leads ASU's Astrobiology Program.
Nano drugs: Insoluble medicines can be made orally available if in nano crystal form
Researchers in India have demonstrated that producing nanoscopic crystals of a pharmaceutical product can allow the medication to be absorbed by the gut even if the drug is not soluble in water. Research suggests that more than half of the medicinal drugs being developed by the pharmaceutical industry dissolve only very weakly in water, if at all.
Study confirms: Whatever doesn't kill us can make us stronger
We've all heard the adage that whatever doesn't kill us makes us stronger, but until now the preponderance of scientific evidence has offered little support for it. However, a new national multi-year longitudinal study of the effects of adverse life events on mental health has found that adverse experiences do, in fact, appear to foster subsequent adaptability and resilience, with resulting advantages for mental health and well being.
Physicists at the University of California, Berkeley in collaboration with researchers from the Max Planck Institute of Quantum Optics and the U.S. Department of Energy's Lawrence Berkeley National Laboratory, became the first researchers to observe the motion of an atom's valence or outermost electrons in real-time by investigating the ejection of an electron from an atom by an intense laser pulse. In the experiments, an electron in a krypton atom is removed by a laser pulse that lasts less than four femtoseconds (one femtosecond is one millionth of one billionth of a second).
Physicists observe electron ejected from atom for first time
Math explains water disasters
The use of Peregrine's theory to explain disasters is made possible with fibre-optics. Image: Henry Brett , Flickr CC-licensed. State-of-the-art optical fibre technology and a 27 year old mathematical theory have been used to demonstrate how extreme events occur - from financial disasters to rogue waves and stampedes - according to researchers from The Australian National University. An international team of researchers, including Professor Nail Akhmediev from the ANU Research School of Physical Sciences and Engineering, have observed the well-known mathematical prediction, ‘Peregrine’s Soliton’, for the first time.
Meteor Flies over the US East Coast, Millions Witness the Event This past Friday evening, around 7:50 p.m., a meteor flew over the US East Coast. Due to the meteor's putting on quite a show, millions got the chance to become aware of its presence and take one good look at it as it passed through the sky. By the looks of it, the meteor was spotted by millions of p... [ read more >> ]