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Astronomers report dwarf star with unexpectedly giant planet

AstronomyIn findings reported on Tuesday, an international team of astronomers discovered an exoplanet, called NGTS-1b, revolving around M-dwarf star NGTS-1, that the team said does not fit existing notions of how stars and planets form. NGTS-1b is a gas giant, similar to Jupiter and of comparable volume and mass, but its parent star is about half the diameter and mass of the Sun, making this the most massive planet orbiting an M-dwarf ever discovered.

NGTS-1b, about 600 light years from the Earth, is so extremely close to its star that a revolution around its star takes only about 2.6 Earth days — 2.647298 ± 0.000020 — and its surface temperature is about 800 K. The planet was discovered by observing periodic fluctuations in the star's apparent brightness as NGTS-1b passed in front of it. NGTS-1b's mass is less than Jupiter, about 0.812 MJ (mass of Jupiter), but it has greater volume, with radius about 1.33 RJ (radius of Jupiter). Its density was reported to be 0.42 g cm-3 (with error: +0.59 to -0.28), meaning Jupiter, whose density is 1.326 g cm-3, is likely around thrice as dense as the exoplanet.

Arrangement of light receptors in the eye may cause dyslexia, scientists say

HealthResearch published in Proceedings of the Royal Society B on Wednesday by Albert Le Floch and Guy Ropars of French University of Rennes claims dyslexia may be caused by the way the photoreceptors in dyslexic individuals' eyes are arranged. Co-author Ropars said, "Our observations lead us to believe that we indeed found a potential cause of dyslexia".

In dyslexic individuals, the pattern of photoreceptors in the right eye is similar to that on the left and produces a "mirror image", while in non-dyslexic individuals, there are two different patterns in the two eyes, researchers found in their study. Individuals with dyslexia have difficulty reading, especially distinguishing between letters that are mirror images of each other, like the characters 'b' and 'd' or 'p' and 'q'.

In the back of the eye, there is a site called the fovea which contains cone cells, of three kinds responding either to red, green, or blue light. In one patch within the fovea, there are cone cells for red and green but none for blue. In the dominant eye, with greater connectivity to the brain, this spot was found to be round while in the other eye, it was asymmetrical. This, researchers speculate, allows the brain to choose just one of the two images to work with. The researchers observed the dyslexic individuals have round spots in both eyes, which produces mirror images, and the brain can not decide which one to consider.

"For dyslexic students their two eyes are equivalent and their brain has to successively rely on the two slightly different versions of a given visual scene," the researchers said. According to Ropars, this may also serve as a means of diagnosing dyslexia.

Researchers find preserving spotted owl habitat may not require a tradeoff with wildfire risk after all

BiologyIn a study scheduled for publication in the December 1 issue of Forest Ecology and Management, scientists from the University of California, Davis; USDA Forest Service Pacific Southwest Research Station; and University of Washington have found a way to resolve the conflict that has sprung up between protecting forests from increasingly frequent wildfires and droughts and preserving sufficient habitat for the endangered spotted owl, Strix occidentalis. The study was performed in two national parks in California, United States.

Peggy Whitson, record-breaking 'American space ninja', returns to Earth

AstronomyJust after sunrise on Sunday (1:21 UTC), NASA astronaut and biochemist Peggy Whitson, 57, returned to Earth in Kazakhstan, in a Soyuz capsule, after a 288-day mission in the International Space Station (ISS), bringing her lifetime total days in space to 665, the most for any U.S. astronaut, most for any female astronaut internationally, and eighth overall.

Sun's mood swings not so strange after all, say scientists

AstronomyIn findings published Friday in Science, a multinational team of scientists led by Antoine Strugarek of the University of Montreal announced the Sun may not be the cosmic oddball amongst solar-type stars some astronomers believe it to be. They found that, although the Sun's cycles appear to differ from those of other stars of its type, they are governed by the same laws working in the same way.

The Sun has long been known to go through eleven-year cycles of high and low activity, including sunspots, which Strugarek likened to solar volcanoes. Times of high activity are also the most likely time for coronal mass ejections, which often emanate from sunspot regions. On rare occasions these eruptions of plasma may hit the Earth's magnetic field, setting it oscillating. It then releases previously trapped particles as the Aurora Borealis and Australis. Occasionally, the effects are so intense that these charged particles and magnetic effects can ding the performance of satellites and power grids. The poles flip at the time of high activity, and the intensity of the magnetic field peaks when the Sun is least active. A hypothetical heat-proof compass on the surface of the Sun would point toward one pole during one eleven-year period but toward the other during the next.
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