Tag: ET (page 2 of 54)

Astrophysicists create most complete 3-D map of the universe






Excerpt from thespacereporter.com


A team of scientists has created a detailed map of our cosmic “neighborhood” extending nearly two billion lights years in every direction. This 3-D map showing galaxies in their superclusters will aid astrophysicists in better understanding how matter, including dark matter, is distributed in the universe.

According to a Science Daily report, the map indicates the relative concentration of galaxies in different areas, including the largest nearby supercluster called the Shapely Concentration, as well as less explored areas. The scientists found no sign of any pattern in the distribution of matter.

“The galaxy distribution isn’t uniform and has no pattern. It has peaks and valleys much like a mountain range. This is what we expect if the large-scale structure originates from quantum fluctuations in the early universe,” Mike Hudson of the University of Waterloo said in a statement.

 

The researchers hope that a more complete view of the placement and movement of matter will aid in forming predictions about the expansion of the universe. In particular, the team hopes to gain insight into the phenomenon of peculiar velocity – the differences in galactic movement caused by the unevenness in the expansion of the universe. It is thought that the non-uniform movement of galaxies is influenced by dark matter – a form of matter only indirectly detectable through its gravitational influence on light and visible matter.



A cross-section of the cosmic map detailing accumulations of massive clusters. The dark red region is the famous Shapley Concentration, the largest collection of galaxies in the nearby universe.
Hudson et al./University of Waterloo








“A better understanding of dark matter is central to understanding the formation of galaxies and the structures they live in, such as galaxy clusters, superclusters and voids,” said Hudson.

The team plans to continue expanding and detailing the map in collaboration with additional researchers. The team’s work was published in the journal Monthly Notices of the Royal Astronomical Society.

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Buried Mars Glaciers are Brimming With Water

Researchers have identified thousands of glacier-like formations on the planet.
NASA/Levy et al./Nanna Karlsson



Excerpt from news.discovery.com

Glaciers beneath the dusty sands of Mars contain enough water to coat the planet with more than three feet of ice, a new study shows.
“We have calculated that the ice in the glaciers is equivalent to over 150 billion cubic meters of ice — that much ice could cover the entire surface of Mars with 1.1 meters (3.6 feet) of ice,” Nanna Bjørnholt Karlsson, a post-doctoral researcher the Niels Bohr Institute at the University of Copenhagen, said in a statement.

Radar images previously revealed thousands of buried glacier-like formations in the planet’s northern and southern hemispheres.
That data has now been incorporated into computer models of ice flow to determine the glaciers’ size and hence how much water they contain.

“We have looked at radar measurements spanning 10 years back in time to see how thick the ice is and how it behaves. A glacier is, after all, a big chunk of ice and it flows and gets a form that tells us something about how soft it is. We then compared this with how glaciers on Earth behave and from that we have been able to make models for the ice flow,” she said.

The glaciers are located in belts around Mars between 30 degrees and 50 degrees latitude, roughly equivalent to just south of Denmark’s location on Earth. The glaciers are found on both the northern and southern hemispheres.

The finding could be an important clue to what happened to Mars’ water. The planet, which is now a cold, dry desert, once had oceans, lakes and habitats suitable for microbial life, results from past and ongoing science missions show.

“The ice at the mid-latitudes is an important part of Mars’ water reservoir,” Karlsson said.

Scientists suspect the thick layer of dust covering the ice has saved if from evaporating out into space.

The study appears in this week’s Geophysical Research Letters.

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Black Holes, the Large Hadron Collider, & Finding Parallel Universes

Excerpt from huffingtonpost.comI am a huge science enthusiast and an unabashed science fiction fan. There are tons of really cool stories out there that fire the imagination and even inspire young people to go into science. (I know they did me.) ...

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Powerful solar storm sparks stunning aurora around the world ~ Images of the Northern Lights 2015

Excerpt from cnn.com  A severe solar storm created a stunning display of light in the night sky over parts of the United States, Europe, Australia and New Zealand early Wednesday morning, spotted by those lucky enough to be awake in the wee h...

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New Development in the Controversy of the ‘Yeti’ Hair Samples — Here’s the Latest



 In this undated photo made available by Britain's Channel 4 television of Oxford University genetics professor Bryan Sykes posing with a prepared DNA sample taken from  hair  from a Himalayan animal.  DNA testing is taking a bite out of the Bigfoot legend. After scientists analyzed more than 30 hair samples reportedly left behind by Bigfoot and other related beasts like Yeti and almasty, they found all of them came from more mundane animals like bears, wolves, cows and raccoons. In 2012, researchers at Oxford University and the Lausanne Museum of Zoology issued an open call asking museums, scientists and Bigfoot aficionados to share any samples they thought were from the mythical ape-like creatures. (AP/ Channel 4)
In this undated photo made available by Britain’s Channel 4 television of Oxford University genetics professor Bryan Sykes posing with a prepared DNA sample taken from hair from a Himalayan animal.



Excerpt from theblaze.com

A new study that re-analyzed so-called “yeti” hair samples from previous research that had identified them as belonging to an “anomalous ursid” might have disappointing news for those who thought the findings last year meant a “bigfoot” of sorts was still out there. Yet, the author of the original findings stands by his claims.

Research published in the journal ZooKeys found that the hair samples said to be from Central Asia and the Himalayas belong to a known species in those regions.

“We have concluded that there is no reason to believe that the two samples came from anything other than brown bears,” the authors wrote in the study abstract.


After scientists analyzed more than 30 hair samples reportedly left behind by Bigfoot and other related beasts like Yeti, they found all of them came from more mundane animals like bears, wolves, cows and raccoons. Two samples were said to have been from an “anomalous ursid,” but new analysis suggests that the samples were from brown bears. (AP/Channel 4)
These authors used mitochondrial 12S rRNA sequencing on the same samples that Oxford University’s Bryan Sykes and his fellow authors used in their study published last year. The issue Eliecer Guiterrez, a postdoctoral researcher at the Smithsonian’s National Museum of Natural History, and his colleagues found with Sykes research was that his team used a fragment of DNA.

“We made this discovery that basically that fragment of DNA is not informative to tell apart two species of bears: the brown bear and [modern-day Alaskan] polar bear,” Gutierrez told Live Science.

At the time of his 2014 study, Sykes et al. wrote “[...] it is important to bear in mind that absence of evidence is not evidence of absence and this survey cannot refute the existence of anomalous primates, neither has it found any evidence in support. […] The techniques described here put an end to decades of ambiguity about species identification of anomalous primate samples and set a rigorous standard against which to judge any future claims.”

And Sykes still holds his ground, despite the more recent findings.
“What mattered most to us was that these two hairs were definitely not from unknown primates,” Sykes told Live Science in light of the recent research. “The explanation by Gutierrez and [Ronald] Pine might be right, or it might not be.”

To NBC News, Sykes said that Gutierrez’ findings are “entirely statistical.”

“The only way forward, as I have repeatedly said, is to find a living bear that matches the 12S RNA and study fresh material from it,” he continued. “Which involves getting off your butt, not an activity I usually associate with desk-bound molecular taxonomists.”

Daniel Loxton, an editor for Junior Skeptic, which is produced by the Skeptics Society, told Live Science that people will continue to believe in and seek out yetis, bigfoots and the like, because they are”fascinated by monsters, and they’re fascinated by mysteries in general.”

Blake Smith, in a blog post for the Skeptics Society laid out the whole saga involving Sykes research and the more recent analysis by Guiterrez. Smith ultimately concluded that he’s “still convinced that Yeti and Bigfoot are not to be found in the forests and mountains of the Earth, but in the minds of people.”

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Rare & severe geomagnetic storm enables Aurora Borealis to be seen from U.S. tonight

Excerpt from mashable.com Thanks to a rare, severe geomagnetic storm, the Northern Lights may be visible on Tuesday night in areas far to the south of its typical home in the Arctic.  The northern tier of the U.S., from Washington State to Michiga...

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Is This a Baby Picture of a Giant Planet?


Hubble optical image (left) and VLT infrared image (right) of the circumstellar disk surrounding HD 100546. (ESO/NASA/ESA/Ardila et al.)


Excerpt from news.discovery.com


Mommy, where do baby planets come from? There’s no storks, birds, bees, or romantic dinners for two involved in the answer to that question — regardless of size, planets are all formed in pretty much the same way: through the aggregation of material within the disk of dust and gas surrounding a young star. While how long it actually takes and just what sort of planets are most likely to form where are still topics of discussion among astronomers, the birth process of a planet is fairly well understood.

And this may be the very first image of it actually happening.

Acquired by the European Southern Observatory’s Very Large Telescope (VLT), the infrared image above (right) shows a portion of the disk of gas and dust around the star HD100546, located 335 light-years away in the constellation Musca. By physically blocking out the light from the star itself by means of an opaque screen — seen along the left side of the image — the light from the protoplanetary disk around HD 100546 can be seen, revealing a large bright clump that’s thought to be a planet in the process of formation.

If it is indeed a baby planet, it’s a big one — as large as, or perhaps even larger than, Jupiter.

A candidate protoplanet found in a disc of gas and dust around young star HD100546 (ESO)


This does raise an interesting question for astronomers because if it is a Jupiter-sized planet, it’s awfully far from its star… at least according to many current models of planetary formation. About 68 times as far from HD100546 as we are from the sun, if this planet were in our solar system it’d be located deep in the Kuiper Belt, twice as far as Pluto. That’s not where one would typically expect to find gas giants, so it’s been hypothesized that this protoplanet might have migrated outwards after initially forming closer to the star… perhaps “kicked out” by gravitational interaction with an even more massive planet.

Alternatively, it may not be a planet at all — the bright blob in the VLT image might be coming from a much more distant source. While extremely unlikely, further research will be needed to rule that possibility out.

If it’s found to be a planet, HD100546 “b” would offer scientists an unprecedented opportunity to observe a planetary formation process in action — and from a relatively close proximity as well.

According to the team’s paper, submitted to Astrophysical Journal Letters, ”What makes HD100546 particularly interesting is that 1. it would be the first imaged protoplanet that is still embedded in the gas and dust disk of its host star; and 2. it would show that planet formation does occur at large orbital separations.”

(Now all we have to do is wait a couple billion years and then show these pictures to HD100546b’s girlfriend. How embarrassing!)

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Exoplanet Imager Begins Hunt for Alien Worlds


This infrared image shows the dust ring around the nearby star HR 4796A in the southern constellation of Centaurus.


Excerpt from news.discovery.com

By Ian O'Neill

A new instrument attached to one of the most powerful telescopes in the world has been switched on and acquired its ‘first light’ images of alien star systems and Saturn’s moon Titan.
The Spectro-Polarimetric High-contrast Exoplanet REsearch (or SPHIRES) instrument has been recently installed at the ESO’s Very Large Telescope’s already impressive suite of sophisticated instrumentation. The VLT is located in the ultra-dry high-altitude climes of the Atacama Desert in Chile.

In the observation above, an ‘Eye of Sauron‘-like dust ring surrounding the star HR 4796A in the southern constellation of Centaurus, a testament to the sheer power of the multiple technique SPHIRES will use to acquire precision views of directly-imaged exoplanets.

The biggest problem with trying to directly image a world orbiting close to its parent star is that of glare; stars are many magnitudes brighter that the reflected light from its orbiting exoplanet, so how the heck are you supposed to gain enough contrast between the bright star and exoplanet to resolve the two? The SPHIRES instrument is using a combination of three sophisticated techniques to remove a star’s glare and zero-in on its exoplanetary targets.

This infrared image of Saturn’s largest moon, Titan, was one of the first produced by the SPHERE instrument soon after it was installed on ESO’s Very Large Telescope in May 2014.
ESO 
The first technique, known as adaptive optics, is employed by the VLT itself. By firing a laser into the Earth’s atmosphere during the observation, a gauge on the turbulence in the upper atmospheric gases can be measured and the effects of which can be removed from the imagery. Any blurriness caused by our thick atmosphere can be adjusted for.

Next up is a precision coronograph inside the instrument that blocks the light from the target star. By doing this, any glare can be removed and any exoplanet in orbit may be bright enough to spot.

But the third technique, which really teases out any exoplanet signal, is the detection of different polarizations of light from the star system. The polarization of infrared light being generated by the star and the infrared glow from the exoplanet are very subtle. SPHIRES can differentiate between the two, thereby further boosting the observation’s contrast.

“SPHERE is a very complex instrument. Thanks to the hard work of the many people who were involved in its design, construction and installation it has already exceeded our expectations. Wonderful!” said Jean-Luc Beuzit, of the Institut de Planétologie et d’Astrophysique de Grenoble, France and Principal Investigator of SPHERE, in an ESO press release.

The speed and sheer power of SPHIRES will be an obvious boon to astronomers zooming in on distant exoplanets, aiding our understanding of these strange new worlds.


The star HR 7581 (Iota Sgr) was observed in SPHERE survey mode (parallel observation in the near infrared with the dual imaging camera and the integral field spectrograph ). A very low mass star, more than 4000 times fainter that its parent star, was discovered orbiting Iota Sgr at a tiny separation of 0.24". This is a vital demonstration of the power of SPHERE to image faint objects very close to bright ones.
ESO

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Hubble’s ‘Einstein Cross’ Marks the Space-Warping Spot


Image: Einstein Cross revealed
Flash from the supernova's blast has been warped into four points of light surrounding an elliptical galaxy in a cluster called MACS J1149.2+2223, which is 5 billion light-years away in the constellation Leo.


Excerpt from nbcnews.com
By Alan Boyle


One hundred years after Albert Einstein published his theory of general relativity, the Hubble Space Telescope has provided a demonstration of the theory at work: a picture of a distant galaxy so massive that its gravitational field is bending the light from an even more distant supernova. 

The image, released Thursday, shows how the flash from the supernova's blast has been warped into four points of light surrounding an elliptical galaxy in a cluster called MACS J1149.2+2223, which is 5 billion light-years away in the constellation Leo. 

"It really threw me for a loop when I spotted the four images surrounding the galaxy," Patrick Kelly, an astronomer from the University of California at Berkeley, said in a news release. "It was a complete surprise." 

Maybe it shouldn't have been. The configuration is known as an Einstein Cross. It's a well-known but rarely seen effect of gravitational lensing, which is in line with Einstein's assertion that a massive object warps the fabric of space-time — and thus warps the path taken by light rays around the object. 

In this case, the light rays are coming from a stellar explosion that's directly behind the galaxy, but 4.3 million light-years more distant. Computer models suggest that the four-pointed cross will eventually fade away, to be followed within the next five years by the reappearance of the supernova's flash as a single image. 

Kelly is part of a research collaboration known as the Grism Lens Amplified Survey from Space, or GLASS. The collaboration is working with the Frontier Field Supernova team, or FrontierSN, to analyze the exploding star. He's also the lead author of a paper on the phenomenon that's being published this week by the journal Science as part of a package marking the 100th anniversary of Einstein's general relativity theory. 

The researchers suggest that a high-resolution analysis of the gravitational lensing effect can lead to better measurements of cosmic distances and galactic masses, including the contribution from dark matter. The Hubble team says the faraway supernova has been named "Refsdal" in honor of Norwegian astronomer Sjur Refsdal, who proposed using time-delayed images from a lensed supernova to study the expansion of the universe. 

"Astronomers have been looking to find one ever since," UCLA astronomer Tommaso Treu, the GLASS project's principal investigator, said in Thursday's news release. "The long wait is over!" 

The Einstein Cross is the subject of a Google+ Hangout at 3 p.m. ET Thursday, presented by the Hubble science team. You can watch the event now or later via YouTube. Check out a preprint version of the Science report.

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