Tag: matter (page 21 of 63)

New EAGLE Simulation Shows Galaxies as They Really Are ~ Video


The EAGLE simulation of the universe generates a more accurate picture of galaxies than any simulation of this size before it.



Excerpt from space.com

Galaxies come in all different shapes and sizes, and a massive new simulation of the universe has captured that galactic variety with more accuracy than any simulation before it, according to a new study.

Using a simulation called EAGLE (Evolution and Assembly of GaLaxies and their Environments), researchers from multiple institutes in Europe have cooked up a dazzling simulation of the universe that contains tens of thousands of galaxies.



A sample of the new simulation can be seen in the video above. It shows the evolution of the universe in a region 25 megaparsecs cubed (about 81 million light years).



"This is really a staggering success, I think it's fair to say," Rob Crain from Liverpool John Moores University and a member of the group that built EAGLE, told Space.com. The researchers are part of a collaboration called the Virgo Consortium for Cosmological Supercomputer Simulations. "Go to our previous generation of simulations, and the galaxies all look like big spherical blobs. Now they form disks and bars and irregular galaxies and different types of ellipticals."

A computer simulation is like a recipe for the universe. Scientists have to start with a list of ingredients and instructions — which actually means a description of the physics that underlie the current universe. While many simulations can recreate the major cosmic ingredients (like stars and galaxies), the subtleties are harder to achieve (like the shape, mass and distribution of those stars and galaxies).

The bottom right corner of the screen shows the time after the Big Bang (denoted by "t"). In the early universe, matter is dispersed and hazy, but gradually coalesces into a sort of web, with long strands of material connecting nodes where galaxies are clustered. At 1:06, the simulation starts again from the beginning and shows the three major components of the model: dark matter (labeled as CDM), gas (the red globs are gas clouds where stars are often born), and stars. The full EAGLE simulation contains an area 100 megaparsecs cubed.

One goal of the EAGLE group was to produce a simulation large enough that it contained all types of galaxies seen in the universe. This allows the researchers to find out if the physics they programmed into EAGLE are accurate for all galaxies, and if they produce the correct number of galaxies in the universe.




Schaye said the picture of the universe created by the EAGLE simulation "is not perfect, but for astronomers the level of agreement is very impressive. It seems we have the main ingredients in place."

View Article Here   Read More

Is AI a threat to humanity?

Excerpt from cnn.comImagine you're the kind of person who worries about a future when robots become smart enough to threaten the very existence of the human race. For years, you've been dismissed as a crackpot, consigned to the same category of peop...

View Article Here   Read More

Dinosaur Researchers Say They’re in a ‘Golden Age’ of Discovery Due to the ‘Jurassic Park’ effect




Excerpt from nbcnews.com

This was a great year for dinosaurs. Dreadnoughtus, "Jar Jar Binks," and a swimming Spinosaurus all made headlines — and 2015 could hold even more surprises. 

It wasn't always like this. From 1984 to 1994, there were about 15 new dinosaur species named per year. This year, nearly one species was discovered every week. 

"We're absolutely in a golden age of dinosaur discovery," David Evans, who oversees dinosaur research at the Royal Ontario Museum, told NBC News. "It is probably a better time to be a dinosaur paleontologist now than any other time in the last century." 

The 'Jurassic Park' effect

When it comes to finding dinosaurs in the dirt, paleontologists are using the same tools that they were 30 years ago. Satellite images might give them a better view of dig sites, but for the most part the process has not changed much. 

So why are there so many dinosaur discoveries these days? More people are looking for them. Evans estimates that the number of dinosaur paleontologists has more than quadrupled in the last 30 years. 

Every paleontologist interviewed for this story pointed to one catalyst for the paleontology boom: Steven Spielberg's 1993 blockbuster "Jurassic Park." 

"It put the most lifelike, scientifically accurate dinosaurs ever on the big screen," Evans said. "That helped the public moved beyond the classical view of dinosaurs as slow, dim-twitted creatures."
Famed Montana State University paleontologist Jack Horner admits he has a special affection for the film. He served as scientific adviser for the original "Jurassic Park" and was the inspiration for Dr. Alan Grant, the movie's protagonist. He also consulted on the upcoming "Jurassic World" starring Chris Pratt.

"'Jurassic Park' attracted an incredible number of people to the field," Horner told NBC News. "I'm hoping that we put together something cool with 'Jurassic World' that people will really like and get more children interested in paleontology." 

Increased interest led to increased paleontology budgets for museums and universities, Evans said. That has made a big difference in places like China and Argentina, relatively unexplored areas where a new generation of paleontologists has unearthed most of the recent headline-grabbing discoveries. 

"The number of dinosaur researchers is much higher now than in the '90s," Thomas Holtz, a vertebrate paleontologist at the University of Maryland, told NBC News. "Anytime you are exploring a region and a slice of time that hasn't been sampled before, chances are that everything you are finding is new."

2014 and beyond

Some of the biggest discoveries of the year were not new species. Instead, they were more complete fossils of dinosaurs the scientific community knew very little about. 

Take Spinosaurus, a massive carnivore that was even bigger than Tyrannosaurus rex. While its teeth indicated it ate fish, scientists were divided on whether it roamed the land and water looking for prey.

This year, the matter was settled. A new paper showed that the dinosaur's unique body structure — tiny hind limbs, dense bones, crocodile-like receptors in its snout — was best suited for the water and caused it to waddle on land. 

"That was probably the most significant find of the year," Horner said. 

There were other big discoveries in 2014. Dreadnoughtus fossils discovered in Argentina belonged to a creature that measured 85 feet (26 meters) long and weighed about 65 tons (59 metric tons), or about as much as a dozen elephants. 


Image: Deinocheirus mirificus, the largest known member of a group of ostrich-like dinosaurs 
This undated handout image provided by Michael Skrepnick, Dinosaurs in Art, Nature Publishing Group, shows a Deinocheirus mirificus, the largest known member of a group of bird-like dinosaurs.

View Article Here   Read More

Does the Theory of Evolution Really Matter? Video Presentation

Students who may be disinterested or uncomfortable with the science of evolution often wonder why it is worth their time and effort to understand. Stated Clearly and Emory University's Center for Science Education have joined forces to create this a...

View Article Here   Read More

What happens when you point a telescope for black holes at the sun?

The first image of the sun captured by NASA's Nuclear Spectroscopic Telescope Array (NuSTAR), which is sensitive to high-energy X-ray light. X-rays seen by NuSTAR show up as green and blue in the photo, which is overlaid on an image taken by NASA's Solar Dynamics Observatory.

Excerpt from
csmonitor.com


A NASA space telescope designed to peer at faraway black holes has snapped a stunning image of the sun, showing that its sensitive X-ray eyes can investigate mysteries in Earth's own neighborhood.
The new image, which was taken by NASA's NuSTAR spacecraft (short for Nuclear Spectroscopic Telescope Array), is the best-ever view of the sun in high-energy X-ray light, space agency officials said. The photo, and others taken by NuSTAR in the future, should help researchers learn more about our star, they added.

"NuSTAR will give us a unique look at the sun, from the deepest to the highest parts of its atmosphere," NuSTAR team member David Smith, of the University of California, Santa Cruz, said in a statement. 

The new image, which was released Monday (Dec. 22), overlays NuSTAR observations (seen in blue and green) onto an image of the sun captured by NASA's Solar Dynamics Observatory spacecraft.

NuSTAR solar observations might also reveal more about the nature of dark matter, the mysterious stuff thought to make up most of the material universe.

Dark matter apparently does not emit or absorb light — hence its name — and nobody knows for sure what it's made of. A number of exotic particles have been proposed as dark matter constituents, including weakly interacting massive particles, sterile neutrinos and axions.

If axions exist, NuSTAR may see signs of them — patches of X-rays in the center of the sun — NASA officials said.

View Article Here   Read More

The Particle at the End of the Universe ~ Opening a door into the mind-boggling domain of dark matter

 It was the universe's most elusive particle, the linchpin for everything scientists dreamed up to explain how stuff works. It had to be found. But projects as big as CERN's Large Hadron Collider don't happen without dealing and conniving, incr...

View Article Here   Read More

Richard Branson shelves submarine plan to take tourists to bottom of oceans




 


Excerpt from
independent.co.uk

It is one of the world’s last frontiers and has seen fewer human visitors than the moon. And that – for the time being at least – is how it shall stay.

Sir Richard Branson has shelved plans for a submarine to take tourists to the bottom of Pacific’s Mariana Trench, after technical problems hobbled the grand ambitions of his much-trumpeted Virgin Oceanic project.

The news is a second blow to Branson’s adventurer dreams in a matter of months, after a Virgin Galactic space rocket crashed on a test flight in California’s Mojave Desert, killing a pilot.
Virgin Oceanic’s DeepFlight Challenger was launched in 2011 with the entrepreneur’s familiar fanfare. Under the plans, wealthy passengers or “aquanauts” up would pay up to $500,000 (£318,126) for a five-dive package labelled as “the last great challenge for humans”.  

As well as exploring the Mariana Trench – a  36,000ft-deep abyss is deeper than Mount Everest is tall, with access so risky and complicated that it has had just three human visitors since its formation nine million years ago – the submarine was due to dive the Puerto Rico trench 28,000ft below the surface of  the Atlantic, the Molloy Deep in the Arctic, South Sandwich Trench in the Southern Ocean and Diamantina trench in the Indian Ocean.
But yesterday the Sunday Telegraph reported that Deepflight, the company contracted to build the submarine, could not support the project because their vehicle could only be safely used for one dive.
The underwater mission appears to have stalled indefinitely. The Virgin Oceanic website – which had promised “five dives, five oceans, two years, one epic adventure” – no longer exists, reportedly taken down earlier this year.

View Article Here   Read More

Is This What Really Killed the Dinosaurs?


Portrait of a killer: volcanoes were no friend to the dinos

Excerpt from time.com 

It wasn't just an asteroid

At the start of the 1980s, the question of what forced dinosaurs and huge numbers of other creatures to become extinct 65 million years ago was still a mystery. By the decade’s end, that mystery was solved: a comet or asteroid had slammed into Earth, throwing so much sun-blocking dust into the air that the planet plunged into a deep-freeze. The discovery of a massive impact crater off the coast of Mexico, of just the right age, pretty much sealed the deal in most scientists’ minds.

But a second global-scale catastrophe was happening at much the same time: a series of ongoing volcanic eruptions that dwarf anything humans have ever seen. They were so unimaginably powerful that they left nearly 200,000 square miles (518,000 sq. km) of what’s now India buried in volcanic basalt up to a mile and a half thick. And the gases and particulate matter spewed out by those eruptions, argue at least some scientists, could have played a big role in the dinosaurs’ doom as well.
How big a role, however, depends on exactly when the eruptions began and how long they lasted, and a new report in Science goes a long way toward answering that question. “We can now say with confidence,” says Blair Schoene, a Princeton geologist and lead author of the paper, “that the eruptions started 250,000 years before the extinction event, and lasted for a total of 750,000 years.” And that, he says, strengthens the idea that the eruptions could have contributed to the mass extinction of multiple species.

Schoene and his co-authors don’t claim volcanoes alone wiped out the dinosaurs; only that they changed the climate enough to put ecosystems under stress, setting them up for the final blow. “We don’t know the exact mechanism,” he admits. Volcanoes emit carbon dioxide, which could have triggered an intense burst of global warming, but they also emit sulfur dioxide, which could have caused global cooling. “What we do know,” Schoene says, “is that earlier mass extinctions were caused by volcanic eruptions alone.” The new dates, he and his co-authors believe, will help scientists understand what role these volcanoes played in the dinosaurs’ demise.

If there was such a role, that is, and despite this new analysis, plenty of paleontologists still doubt it seriously. The dating of the eruptions, based on widely accepted uranium-lead measurement techniques, is not an issue, says Brian Huber, of the Smithsonian Institution. “That part of the science is great,” he says. “It moves things forward.”

And those data, Huber says, make it clear that the extinction rate for the 250,000 years leading up to the asteroid impact wasn’t especially large. Then, at the time of the impact: whammo. The idea that volcanoes played a significant role in this extinction event keeps coming up every so often, and in Huber’s view, “the argument has gotten very tiresome. I no longer feel the need to put any energy into it. It’s from a minority arguing against overwhelming evidence.”

View Article Here   Read More

Older posts Newer posts

Creative Commons License
This work is licensed under a
Creative Commons Attribution 4.0
International License
.
unless otherwise marked.

Terms of Use | Privacy Policy



Up ↑