cwl

Big Gulp: Flaring Galaxy Marks the Messy Demise of a Star in a Supermassive Black Hole

A close look at a distant cataclysm indicates that the black hole’s victim was a red giant star

Once in a while, a supermassive black hole gets a sumptuous treat. A passing star wanders too close and gets caught in the black hole’s gravitational pull, like a fly trapped in a spider’s web. The star then becomes an easy meal for the black hole, which tears its prey to bits and ingests a good portion of it.

Astronomers have witnessed several such disruptions before in distant galaxies, but usually only toward the end of the process. (These feedings are far too rare, however, to have been witnessed in our own Milky Way anytime in recent human history; they occur only once every 10,000 years or so per galaxy.) Now researchers have documented a black hole’s feasting in such detail that they were able to infer its size as well as the type of star that fell prey to its gluttony.

Astronomers cannot peer inside a black hole itself; beyond the event horizon, a black hole’s point of no return, even light cannot escape into the outside world. But material falling into a black hole gives off intense flares of radiation as it compresses and heats up outside the event horizon.

Suvi Gezari, an astronomer at Johns Hopkins University, and her colleagues used a number of different telescopes to track the outburst from a supermassive black hole in a galaxy more than two billion light-years away as the black hole consumed a star that ventured too close.

“While there has been evidence of these types of flares before, there’s never been enough information to say what kind of star fell victim to the black hole, and what was the mass of the black hole that destroyed the star,” Gezari says. She and her colleagues published their findings online May 2 in Nature.

Full Article

Close Encounters of the AEHF-2 Kind

Dramatic backlight illuminates a United Launch Alliance Atlas V launch vehicle at Space Launch Complex-41 of Cape Canaveral Air Force Station in Florida.

Pacman & Pie charts

Astronaut Don Pettit, on board the International Space Station as a member of Expedition 30/31 tweeted this photo from space. He described it as: “Pac-man in Brazil as seen from ISS http://pic.twitter.com/0tP9EgoP.”

Cloud Bank Rolling across Lake Michigan

Copyright: Amy & Jim Ferris

An Arcus cloud is a low, horizontal cloud formation. Roll clouds and shelf clouds are the two types of arcus clouds. A shelf cloud is usually associated with the leading edge of thunderstorm outflow; roll clouds are usually formed by outflows of cold air from sea breezes or cold fronts in the absence of thunderstorms.

Logarithmic Spirals

Image Credit: M101 - NASA, ESA, CFHT, NOAO; Typhoon Rammasun - MODIS, NASA Comparison: Lawrence Anderson-Huang (Ritter Astrophysical Obs., Univ. Toledo)

Uncomfortably close Typhoon Rammasun (right) and 25 million light-year distant galaxy M101 don’t seem to have much in common.

For starters, Rammasun was only a thousand kilometers or so across while M101 (aka the Pinwheel Galaxy) spans about 170,000 light-years, making them vastly dissimilar in scale, not to mention the different physical environments that control their formation and development.

But they do look amazingly alike: each with arms exhibiting the shape of a simple and beautiful mathematical curve known as a logarithmic spiral, a spiral whose separation grows in a geometric way with increasing distance from the center.

Also known as the equiangular spiral, growth spiral, and Bernoulli’s spiral or spira mirabilis, this curve’s rich properties have fascinated mathematicians since its discovery by 17th century philosopher Descartes.

Intriguingly, this abstract shape is much more abundant in nature than suggested by the striking visual comparison above. For example, logarithmic spirals can also describe the tracks of subatomic particles in a bubble chamber, the arrangement of sunflower seeds and, of course, cauliflower.

Starry Night of Iceland

Breathtaking View of Earth Taken by Russian Satellite

Think of it as an amped up version of the iconic “Blue Marble” image. A new photo of Earth from space highlights the striking beauty and intensely rich colors of our home planet.

The photo was taken by a Russian weather satellite, called Elektro-L No.1, which flies in a geostationary orbit more than 22,000 miles (35,700 kilometers) above the Earth’s equator.

The image was posted by James Drake on the Planet Earth website. Drake obtained the photo from the Russian Federal Space Agency’s Research Center for Earth Operative Monitoring, which manages the Elektro-L No. 1 spacecraft, after he expressed interest in animating and publishing them.

M97

Copyright: Tim Jardine

Private Space Taxi Builders Ponder Future Beyond NASA

Image: Dragon and Falcon 9 Second Stage, post Second Stage Separation Credit: NASA

Side Note: I think spaceflight companies ought to take SpaceX as a shining example of where their heads ought to be in commercial space flights. It’d be smarter to go about it this way and look for funding outside of NASA considering our government’s space agency does not get as much support or budget raises compared to other organizations and defense budget in the U.S. Looking for outside help, commercializing a large portion of space exploration and incorporating a lot of research into the preparation and actual flights seems more feasible when you consider the severe lack of funding in NASA.

The private spaceflight company SpaceX is poised to launch a robotic capsule toward the International Space Station Saturday (May 19) on a test flight that, if successful, could be a watershed moment for the commercial space industry.

But while SpaceX has a NASA contract to provide cargo deliveries to the space station, the company and other private spaceship developers are looking to a future beyond NASA funding.

The Hawthorne, Calif.-based SpaceX is one of several aerospace firms who are competing for NASA funding under the third and final phase of NASA’s commercial crew development program. Proposals for this stage of the competition, called Commercial Crew integrated Capability(CCiCap), require companies to present a complete launch system — rocket and vehicle — for consideration.

SpaceX intends to use a version of its current cargo ship, the robotic Dragon capsule,to fly up to seven passengers to the International Space Station and other destinations in low-Earth orbit. The spacecraft will launch atop the company’s own Falcon 9 rocket from the Cape Canaveral Air Force Station in Florida.

Private spaceships of tomorrow

SpaceX isn’t alone in the private spaceship game. The company is facing some stiff competition from other aerospace firms, including Boeing and Sierra Nevada Corp. NASA is expected to announce at least two recipients for CCiCap funding awards in August.

Some of the contenders have said they intend to forge ahead with the development of their spacecraft regardless of whether they receive NASA funding or not.

Continue..

Tracking Ocean Sulfur Could Help Test Gaia Hypothesis

A few months ago I posted an article on the cwl blog explaining the Gaia theory, it’s essentially a theory that states there could be an underlying system of control covering the Earth, a system that acts to the survival of the planet. Here’s a nice accompanying article by Wired delving into a new research published which attempts to prove or disprove the Gaia theory:

Geologists at the University of Maryland have published research that could help prove or disprove Gaia theory — the notion that the Earth is one single self-regulating system.

The concept dates from the 70s and was initially formulated by James Lovelock and Lynn Margulis. It proposes that all organisms and their inorganic surroundings comprise a single system that maintains the conditions for life on Earth. It was initially met with skepticism from the scientific community, and remains somewhat controversial, but is now an important area of research in Earth systems science and biogeochemistry.

If the Gaia hypothesis is correct, then a number of signals should be observable in the Earth’s natural cycles and systems. One of those is that a sulfur compound made by organisms in the ocean should be stable enough in water to allow its transfer into the air, so it can then be returned to land. A team of geologists, geochemists and marine biologists led by Harry Oduro has developed a method of tracking the movement of sulfur through ocean organisms, the atmosphere and the land, potentially yielding evidence as to how strong this cycle is.

Oduro and his colleagues tracked two compounds — dimethylsulfoniopropionate (or DMSP), which is produced by plant plankton and seaweed in the ocean, and dimethylsulphide, which has a distinctive cabbage-like smell, and is produced when marine microbes break down DMSP.

By examining the differences in the isotope ratios between the compounds over time, the researchers were able to trace unique combinations of an element’s radioactive isotopes, keeping track of them to determine the rate at which the microbes metabolize DMSP into dimethylsulfide, and therefore get clues as to how fast it’s transferred from the ocean into the atmosphere.

Full Article

Venus: Earth’s Cloudy Twin

M81

Bright Spiral Galaxy M81 in Ultraviolet from Galex

Why We Dream: Real Reasons Revealed

The slumbering mind might not seem like an apt tool for any critical thinking, but humans can actually solve problems while asleep, researchers say. Not only that, but one purpose for dreaming itself may be to help us find solutions to puzzles that plague us during waking hours.

Dreams are highly visual and often illogical in nature, which makes them ripe for the type of “out-of-the-box” thinking that some problem-solving requires, said Deirdre Barrett, a psychologist at Harvard University.

Barrett’s theory on dreaming, which she discussed at the Association for Psychological Science meeting here last month, boils down to this: Dreaming is really just thinking, but in a slightly different state from when our eyes are open.

“Whatever the state we’re put in, we’re still working on the same problems,” Barrett said. Although dreams might have initially evolved for a different purpose, they likely have been refined over time so they can serve double-duty: help the brain reboot itself and problem-solve.

Dreams and evolution

A theory to explain dreams, or any human behavior for that matter, needs to take into account evolution, Barrett said. But many early theories of dreaming either didn’t address evolution at all, or downright contradicted it, she said.

For instance, Sigmund Freud proposed dreams exist to fulfill our wishes. But such gratification in an imaginary world would do little to help us adapt our instincts to the physical world, which is one key point of evolution, Barrett said.

Others have proposed dreams are more of a side effect of the sleep cycle. Dreams usually occur during Rapid Eye Movement, or REM, sleep. This stage is thought to serve several functions: to rest a part of the brain (since some areas are active while others aren’t) and to replenish brain chemicals, such as neurotransmitters.

This has led some to say that dreams happen simply because REM sleep happens, Barrett said. The psychologist Steven Pinker once likened dreams to computer screen savers, saying that it perhaps “doesn’t really matter what the content is as long as certain parts of the brain are active.”

However, Barrett disagrees. “My opinion is that, evolution just isn’t wasteful, that when things evolve for one purpose, that generally they don’t continue throughout time to have only that purpose, but anything else that may be useful about them gets refined,” she said in a telephone interview with LiveScience prior to the convention.

She also noted that REM sleep has been around for quite some time, since mammals evolved some 220 million years ago. “The longer something has existed during evolutionary history, the likelier it is to have other functions overlaid on it,” she said at the convention.

Problem-solving

Barrett has studied problem-solving in dreams for more than 10 years, and documented many examples of the phenomenon.

In one experiment, Barrett had college students pick a homework problem to try to solve in a dream. The problems weren’t rocket science; they were fairly easy questions that the student simply hadn’t gotten around to solving yet. Students focused on the problem each night before they went to bed. At the end of a week, about half the students had dreamed about the problem and about a quarter had a dream that contained the answer, Barrett said.

So at least in the cases where problems are relatively easy, some people can solve them in their sleep.

Barrett has also extensively reviewed scientific and historical literature, looking for examples of problems solved in dreams.

She found examples of almost every type of problem being solved in a dream, from the mathematical to the artistic. But many were related to problems that required individuals to visualize something in his or her mind, such as an inventor picturing a new device.

The other major category of problems solved in dreams included “ones where the conventional wisdom is just wrong about how to approach the problem,” Barrett said.

Dreams might have evolved to be particularly good at allowing us to work out puzzles that fall into those two categories, she said.

“I think that dreams and REM sleep have probably further evolved to be useful for really as many of the things that our thinking is useful for,” Barrett said. “It’s just extra thinking time, so potentially any problem can get solved during it, but it’s thinking time in the state that’s very visual and looser in associations, so we’ve evolved to use it especially to work on those kinds of problems.”

For More on Dreams

Crowdsourcing the Hunt for Potentially Dangerous Asteroids

Image: Faulkes Telescope, Hawaii. Credit: ESA

What’s the best way to look for potentially hazardous asteroids? Get as many eyes on the sky as you can. That’s the impetus behind a new partnership between the European Space Agency and the Faulkes Telescope Project, which will encourage amateur astronomers to look for asteroids, as well as providing educational opportunities that will allow students to discover potentially dangerous space rocks, too.

Full Article

Star Factory Blazes Bright in Stunning New Photo

Huge, glowing clouds of gas and dust that will one day collapse to form massive new stars take center stage in a new photo from a European space telescope.

The image, snapped by the European Space Agency’s Herschel space observatory, shows Cygnus-X, an extremely active star-forming region about 4,500 light-years from Earth in the constellation Cygnus (The Swan).

The Herschel observatory sees extremely well in far-infrared wavelengths, allowing scientists to seek out and study stellar nurseries like Cygnus-X — places where dense clumps of gas have been gently heated by stars.

In the new photo, bright white areas highlight areas where large stars have recently formed out of such clouds, researchers said. These clumps are particularly evident in the right-hand side of the image, which shows a chaotic network of filaments.

Continue..