Slashdot Mirror

New submitter Jim Geach writes: Our team of astronomers and computer scientists has developed a novel unsupervised machine learning algorithm — a combination of Growing Neural Gas and Hierarchical Clustering — to automatically analyze astronomical images. In effect, the algorithm performs the same task as a human 'eyeballing' an image, automatically identifying and labeling the points of interest. We're aiming to deploy the algorithm on the next generation of astronomical surveys such as LSST and Euclid where no human, or even group of humans, could closely inspect every piece of data. The algorithm could also find application in other fields, such as medical imaging and early disease diagnosis. The results are being presented at the UK National Astronomy Meeting in Wales, and the details of the algorithm are described in this paper.

LeadSongDog writes: The Royal Astronomical Society reports five supermassive black holes (SMBHs) that were previously hidden by dust and gas have been uncovered. The discovery suggests there may be millions more supermassive black holes in the universe than were previously thought. George Lansbury, a postgraduate student in the Centre for Extragalactic Astronomy, at Durham University, said: “For a long time we have known about supermassive black holes that are not obscured by dust and gas, but we suspected that many more were hidden from our view. Thanks to NuSTAR for the first time we have been able to clearly see these hidden monsters that are predicted to be there, but have previously been elusive because of their ‘buried’ state. Although we have only detected five of these hidden supermassive black holes, when we extrapolate our results across the whole Universe then the predicted numbers are huge and in agreement with what we would expect to see.”

An anonymous reader writes New observations of the star cluster Messier 54 show that it is just as deficient in lithium as our own galaxy, furthering a mystery about the element's big bang origins. "Most of the light chemical element lithium now present in the Universe was produced during the Big Bang, along with hydrogen and helium, but in much smaller quantities. Astronomers can calculate quite accurately how much lithium they expect to find in the early Universe, and from this work out how much they should see in old stars. But the numbers don't match — there is about three times less lithium in stars than expected. This mystery remains unsolved, despite several decades of work."

astroengine writes: This may seem a little far fetched, but if our understanding of the physics behind the recently-discovered Higgs boson (or, more specifically, the Higgs field — the ubiquitous field that endows all stuff with mass) is correct, our Universe shouldn't exist. That is, however, if another cosmological hypothesis is real, a hypothesis that is currently undergoing intense scrutiny in light of the BICEP2 results. "The mathematics to arise from accepted Higgs field theory suggests the universe is currently sitting comfortably in a Higgs field energy 'valley.' To get out of this valley and up the adjacent 'hill,' huge quantities of energy would need to be unleashed inside the field. But, if there were enough energy to push the universe over the hill and into the deeper energy valley next door, the universe would simply, and catastrophically, collapse.

This is where the BICEP2 results come in. If their observations are real and gravitational waves in the CMB prove cosmological inflation, the Higgs field has already been kicked by too much energy, pushing the Higgs field over the energy hill and deep into the neighboring valley’s precipice! For any wannabe universe, this is very bad news — the newborn universe would appear as a Big Bang, the Higgs field would become overloaded with an energetic inflationary period, and the whole lot would vanish in a blink of an eye."

The Bad Astronomer writes "Studies of carbon-14 in Japanese trees and beryllium-10 in Antarctic ice indicate the Earth was hit by a big radiation blast in 775 AD. Although very rare, occurring only once every million years or so, the most likely culprit is a gamma-ray burst, a cosmic explosion accompanying the birth of a black hole. While a big solar flare is still in the running, a GRB from merging neutron stars produces the ratio of carbon and beryllium observed, and also can explain why no bright explosion was seen at the time, and no supernova remnant is seen now."

sycodon writes with news of research into how nearby supernovae affected the development of life on Earth. "[Professor Henrik Svensmark] found that the changing frequency of nearby supernovae seems to have strongly shaped the conditions for life on Earth. Whenever the Sun and its planets have visited regions of enhanced star formation in the Milky Way Galaxy, where exploding stars are most common, life has prospered. Prof. Svensmark remarks in the paper, "The biosphere seems to contain a reflection of the sky, in that the evolution of life mirrors the evolution of the Galaxy.' ... The data also support the idea of a long-term link between cosmic rays and climate, with these climatic changes underlying the biological effects. And compared with the temperature variations seen on short timescales as a consequence of the Sun's influence on the influx of cosmic rays, the heating and cooling of the Earth due to cosmic rays varying with the prevailing supernova rate have been far larger.""

Hugh Pickens writes "Planetary scientists say there are aspects to our planet and its evolution that are remarkably strange. In the first place there is Earth's strong magnetic field. No one is exactly sure how it works, but it has something to do with the turbulent motion that occurs in the Earth's liquid outer core and without it, we would be bombarded by harmful radiation from the Sun. Next there's plate tectonics. We live on a planet that is constantly recycling its crust, limiting the amount of carbon dioxide escaping into the atmosphere — a natural way of controlling the greenhouse effect. Then there's Jupiter-sized outer planets protecting the Earth from frequent large impacts. But the strangest thing of all is our big Moon. 'As the Earth rotates, it wobbles on its axis like a child's spinning top,' says Professor Monica Grady. 'What the Moon does is dampen down that wobble and that helps to prevent extreme climate fluctuations' — which would be detrimental to life. The moon's tides have also made long swaths of earth's coastline into areas of that are regularly shifted between dry and wet, providing a proving ground for early sea life to test the land for its suitability as a habitat. The 'Rare Earth Hypothesis' is one solution to the Fermi Paradox (PDF) because, if Earth is uniquely special as an abode of life, ETI will necessarily be rare or even non-existent. And in the absence of verifiable alien contact, scientific opinion will forever remain split as to whether the Universe teems with life or we are alone in the inky blackness."

DarkKnightRadick writes "An undergrad student at the University of Utrecht, Marianne Heida, has found evidence of a supermassive black hole being tossed out of its galaxy. According to the article, the black hole — which has a mass equivalent to one billion suns — is possibly the culmination of two galaxies merging (or colliding, depending on how you like to look at it) and their black holes merging, creating one supermassive beast. The black hole was found using the Chandra Source Catalog (from the Chandra X-Ray Observatory). The direction of the expulsion is also possibly indicative of the direction of rotation of the two black holes as they circled each other before merging."

ninthwave writes "The Guardian is running an article on research into the visible effects of entropy in the Universe. Alan Heavens of The University of Edinburgh did the research also posted at The Royal Astronomical Society with this article" I dunno - expansion, heat death - it all reminds me of a teacher who said "I'm not a premillenialist, postmillenialist - I'm a pan-millenialist, as in it's all going to pan out in the end." Update: 08/18 16:36 GMT by S : Headline fixed.

ninthwave writes "The Guardian is running an article on research into the visible effects of entropy in the Universe. Alan Heavens of The University of Edinburgh did the research also posted at The Royal Astronomical Society with this article" I dunno - expansion, heat death - it all reminds me of a teacher who said "I'm not a premillenialist, postmillenialist - I'm a pan-millenialist, as in it's all going to pan out in the end." Update: 08/18 16:36 GMT by S : Headline fixed.