Tag: formation (page 2 of 16)

Cosmic tsunamis can regenerate ‘dead’ galaxies

April 26, 2015 / / 0 Comments






Excerpt from thespacereporter.com



Astronomers have recently discovered that giant cosmic shockwaves emanating from colliding galaxy clusters are capable of jumpstarting new star generation.

According to a Nature World News report, galaxies are often clustered into groups containing “red and dead” galaxies that stopped forming new stars long ago. Scientists now believe that these “dead” galaxies can be brought back to “life” by colossal cosmic tsunamis.

To uncover this phenomenon, an international team of researchers observed how galaxy clusters can absorb smaller clusters much as a growing city absorbs its suburbs. When galaxy clusters collide during this absorption process, a huge shockwave of energy is created. This shockwave can re-energize the star formation process, causing dormant galaxies to begin producing new stars again.

Scientists from the University of Lisbon and Leiden Observatory came to this conclusion after studying the merging galaxy cluster officially known as CIZA J2242.8+5301 and affectionately known as the “Sausage.” The Sausage cluster, located 2.3 billion light-years away, showed evidence of its dormant galaxies coming to life with a new round of star formation.

“We assumed that the galaxies would be on the sidelines for this act, but it turns out they have a leading role. The comatose galaxies in the Sausage cluster are coming back to life, with stars forming at a tremendous rate. When we first saw this in the data, we simply couldn’t believe what it was telling us,” Andra Stroe of Liden Observatory said in a statement.The researchers are observing an event that actually unfolded one billion years ago, when the 6-million-mph shockwave spread out from the collision of the clusters. The team believes that the new star formation was instigated by the shockwave’s affect on galactic gas.

“Much like a teaspoon stirring a mug of coffee, the shocks lead to turbulence in the galactic gas. These then trigger an avalanche-like collapse, which eventually leads to the formation of very dense, cold gas clouds, which are vital for the formation of new stars,” Stroe said.

Despite the vigorous production of new stars in this instance, the team believes that, after the initial effects of the tsunami take place, the galaxies fall to an even deeper state of dormancy than before.

David Sobral of the University of Lisbon explains that “star formation at this rate leads to a lot of massive, short-lived stars coming into being, which explode as supernovae a few million years later. The explosions drive huge amounts of gas out of the galaxies and with most of the rest consumed in star formation, the galaxies soon run out of fuel. If you wait long enough, the cluster mergers make the galaxies even more red and dead – they slip back into a coma and have little prospect of a second resurrection.”

The study was published in the journal Monthly Notices of the Royal Astronomical Society.

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Mystery Methane Hotspot Over Four Corners — What Is It?

April 10, 2015 / / 0 Comments

 Excerpt from eaglecurrent.com NASA is joining in an effort to have an understanding of the presence of a methane hotspot over the 4 corners area of the United States. How severe is the atmospheric feature?A methane hotspot hovering over t...

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Our sun is five billion years younger than most other stars in our galaxy

April 9, 2015 / / 0 Comments






Excerpt from stgist.com



The sun, or the nearest star from Earth, was formed around 5 billion years after the Milky Way galaxy’s peak production of stars, a new research published in the Astrophysical Journal. 

Using multiple ground based, and space telescopes, including the Magellan Telescopes located at Las Campanas Observatory in South America, a new study was able to confirm that the closest star from us, the Sun, was formed after the so-called stellar “baby boom” of the Milky Way galaxy.

It’s like traveling back in time. Researchers from Texas A&M University in College Station, headed by astronomer Casey Papovich, were able to see the undepicted past of our own galaxy by observing similar regions located billions of light years away from us.

The “baby boom” happened around 10 billion years ago, the new study published in Astrophysical Journal revealed. At that time, the Milky Way galaxy was producing 30 times more stars than today. If so, then our solar system’s 4.6 billion years old Sun was formed more than 5 billion years after the production peak.

Sun’s late formation allowed the solar system we know today to produce planets with heavier elements. Scientists say elements heavier than hydrogen and helium became more abundant in “late to the game systems”, and the death of massive stars that were formed before the Sun had provided materials needed to form planets, including Earth and its complex life forms.

Scientists scanned through a collection of more than 24,000 galaxies, and took at least 2,000 snapshots of galaxies that closely resemble our own. The census has provided the most complete picture yet of how spiral galaxies similar to Milky Way form in the universe.

According to Mr. Papovich, the lead author of the study who also serves as an associate professor in the Department of Physics and Astronomy at A&M University in Texas, they know where to find traces by analyzing how galaxies like our own were formed.

Papovich said his team has provided a data that clearly show the rapid phase of growth around 9 to 10 billion years ago, or at least more than 5 billion years after our Sun formed. They also found the connection between the size of the galaxy, and the formation of stars.

Surprisingly, the robust collection of distant galaxies confirmed that stars formed inside the Milky Way, instead of forming in other smaller baby galaxies that later merged to join the system.

In separate studies, scientists were able to confirm that our own solar system is wetter than thought. Beyond Earth, celestial objects like Jupiter’s Galilean moons Europa and Ganymede, Saturn’s Enceladus, and even the dwarf planet Ceres in the asteroid belt, are hosting fluid slightly similar to Earth’s — and it is highly possible that the Sun’s late formation allowed this setup to exist.

Papovich who worked alongside Texas A&M postdoctoral researchers Vithal Tilvi and Ryan Quadri, were joined by at least two dozen astronomers from other countries. The research is published April 9th entitled “ZFOURGE/CANDELS: ON THE EVOLUTION OF M* GALAXY PROGENITORS FROM z = 3 TO 0.5*.” The research was funded by NASA

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For the first time, scientists find complex organic molecules in an infant star system

April 8, 2015 / / 0 Comments



Artist impression of the protoplanetary disk surrounding the young star MWC 480. ALMA has detected the complex organic molecule methyl cyanide in the outer reaches of the disk in the region where comets are believed to form. This is another indication that complex organic chemistry, and potentially the conditions necessary for life, is universal. (B. Saxton/NRAO/AUI/NSF)



Excerpt from washingtonpost.com

We're not special. Or our complex organic molecules aren't, anyway. And that's good news in the hunt for extraterrestrial life.

In a new study published Wednesday in Nature, astronomers found the first signs of the complex, carbon-based molecules that make life possible on Earth in a protoplanetary disk; the region where cosmic building blocks gather to create planets in a brand-new star system. The cyanides found there are essential to life as we know it: without them, there would be no proteins.

"We know when our own solar system was very young, it was rich in water and complex organics. We know that from observing comets," explained study author Karin Öberg, an assistant professor of astronomy at Harvard. Comets have kept the molecules of our solar system's early days locked up tight ever since, which is why scientists are so eager to study them for clues about Earth's formation. These comets show us that certain organic molecules were common in our solar system's pre-planetary days.

But this is the first time we've seen evidence of such molecules ready to seed another star system with planets that could support life.
"We're finding that we're not that special," Öberg said. "Other young solar systems in the making are also rich in the same volatiles, and in similar proportions."

And in this case, she said, being not-special is a great thing: If other solar systems formed just the way ours did, we can hope that they formed some kind of life, too.

Öberg and her colleagues found the molecules using the Atacama Large Millimeter/submillimeter Array (ALMA), a radio telescope with some pretty sweet resolution. They spotted the complex organics as much as 15 billion kilometers from the star itself, which they believe is right smack dab in the middle of the system's comet-forming region. That means the organics could get locked away in comets, just as the ones in our solar system were, and go out to seed future planets with them (as some believe was the case with Earth).

"It was kind of a chance discovery, because we weren't targeting this specific molecule," Öberg said. So she and her team need to go back and look more systematically. She also hopes they'll be able to find more systems to look at. The star they've observed -- MWC 480, located some 455 light-years away in the Taurus star-forming region -- is twice the mass of the sun, so they also hope to find some that are more similar to our host star.

 "We of course want to know whether this is a really common thing or if we just lucked out on this one," Öberg said.

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Puzzle of Moon’s origin resolved

April 8, 2015 / / 0 Comments


It now seems more probable that a collision between two planets of similar composition led to the formation of the Moon.




Excerpt from nature.com


A nagging problem at the heart of the leading theory of how the Moon formed seems to have been explained away.

The ‘giant impact’ hypothesis, first proposed in the 1970s, suggests that the Moon was formed from the debris scattered when a Mars-sized planet slammed into the early Earth some 4.5 billion years ago. This fits well with what we know about the Moon, including its mass and lack of any significant iron core.

But the theory also implies that the Moon is made up mostly of impactor material. Since lunar and Earth rocks have such similar compositions, this suggests that Earth and the planet that smacked into it resembled each other too. They would have needed to be sister planets, with a relationship much closer than that of any other planetary bodies we have studied in our Solar System. The odds of this being possible were thought to be around a 1% chance, or “uncomfortably rare”, according to Robin Canup, a planetary researcher at the Southwest Research Institute in Boulder, Colorado1.

Better odds

Now it seems that the scenario is not so far-fetched, says Hagai Perets, an astrophysicist at the Israel Institute of Technology in Haifa. He and his colleagues performed simulations of the Solar System’s formation, to investigate how similar planets tend to be to their last giant impactor. They estimated that for 20% to 40% of collisions, the two bodies would be sufficiently similar to explain the Moon’s composition — considerably better odds. The findings are published in Nature2.

The planets would have closely resembled each other because of their similar distance from the Sun, meaning that they would have formed from the same kind of orbiting proto-planetary material. “The Earth and the Moon are not twins born from the same planet, but they are sisters in the sense that they grew up in the same environment,” says Perets.

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VLA photos 18 years apart show dramatic difference in young stellar system

April 3, 2015 / / 0 Comments

Excerpt from bulletinstandard.com  A pair of pictures of a young star, produced 18 years apart, has revealed a dramatic distinction that is giving astronomers with a exclusive, "real-time" appear at how enormous stars create in the e...

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Discovered: A ‘Treasure Chest’ of Ancient Galaxies

March 31, 2015 / / 0 Comments


full sky planck
The full visible sky as seen by the Planck space observatory. The band running through the middle corresponds to dust in our Milky Way galaxy. The black dots indicate the location of the proto-cluster candidates identified by Planck and subsequently observed by the Herschel space telescope. (Photo : ESA and the Planck Collaboration)


Excerpt from natureworldnews.com

Treasure seekers have found the haul of a lifetime, but it wasn't in some ancient temple or mysterious island. Instead, it was in the sky. Researcher using two of the European Space Agency's (ESA) impressive space telescopes have successfully identified what they are calling a "treasure chest" of ancient galaxy clusters, which could help explain how the Universe came to be the way it is today.

That's at least according to a study recently published (PDF) in the journal Astronomy and Astrophysics, which details how cosmologists used the ESA's Planck space observatory to identify the distant precursor galaxy clusters, and then poured over data from the Herschel telescope for a closer look.

"Finding so many intensely star-forming, dust galaxies in such concentrated groups was a huge surprise," Hervé Dole, lead author of the report from the Institut d'Astrophysique Spatiale in France, said in a statement. "We think this is a missing piece of cosmological structure formation."

So what does he mean by that? Let's turn back to the treasure chest metaphor for this one.  While Planck was the space observatory to dig up the chest, it was the Herschel data that allowed experts to look closely at each and every gold coin (galaxy cluster) inside. Now they are able to learn more about each coin's make, mint, and ultimately, its origins.

And that's a big step in better understanding the early Universe. Expects believe that it took a great deal of time after star and galaxies first sprung to life for them to assemble into large clusters. 

A summary of the 14 billion years out Universe has been in existence, as seen by the Plank space telescop. Light coming from some of the oldest parts of the Universe are just reaching the observatory now, allowing for experts to see the incredible uniformity of the early structure, compared to the chaotic beautify of star, galaxy, and cluster formation that crowd space today.
(Photo : ESA – C. Carreau) A summary of the 14 billion years out Universe has been in existence, as seen by the Plank space telescope. Light coming from some of the oldest parts of the Universe are just reaching the observatory now, allowing for experts to see the incredible uniformity of the early matter, compared to the chaotic beautify of star, galaxy, and cluster formation that crowds space today.
Once the clusters formed, their gravitational influence triggered the creation of new stars and galaxies. Dark matter - which is theorized to account for a great deal of each cluster's mass and influence - helped usher along the process of creating stars. But how these large clusters were ultimately assembled and grew is still a mystery.
That's why looking at some of the oldest 'coins' ever made - estimated to date back to up-to 11 billion light-years ago - could be exceptionally helpful.

"We still have a lot to learn about this new population," Dole said in an ESA release. "Hints of these kinds of objects had been found earlier in data from Herschel and other telescopes, but the all-sky capability of Planck revealed many more candidates for us to study."

"Even when we combined the powerful capabilities of Planck and Herschel, we were only scratching the surface of the phenomena taking place at this critical era in the history of our universe, when stars, galaxies and clusters seem to be forming simultaneously," 
added George Helou, director of the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. "That's one of the reasons this finding is exciting. It shows us that there is so much more to be learned.

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Why Luke Skywalker’s binary sunset may be real after all

March 30, 2015 / / 0 Comments






Excerpt from csmonitor.com

Researchers have found Jupiter-scale gas giants orbiting binary stars and estimate that Earth-like planets orbiting binary stars could be as numerous as rocky planets orbiting single-star systems.


For all the sci-fi charm of watching a pair of suns sink below a distant horizon on a planet in a galaxy far, far away, conventional wisdom has held that binary-star systems can't host Earth-scale rocky planets.

As the two stars orbit each other like square-dance partners swinging arm in arm, regular variations in their gravitational tug would disrupt planet formation at the relatively close distances where rocky planets tend to appear.

Not so fast, say two astrophysicists. They argue that only are Tatooine-like planets likely to be out there. They could be as numerous as rocky planets orbiting single-star systems – which is to say, there could be large number of them.

Building rocky planets in a binary system not only is possible, it's "not even that hard," says Scott Kenyon, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., who along with University of Utah astrophysicist Benjamin Bromley performed the calculations.
Researchers have found Jupiter-scale gas giants orbiting binary stars and have estimated that such gas giants are likely to be as common in binary systems as they are in systems with a single star.
"If that's true, then Earth-like planets around binaries are just as common as Earth-like planets around single stars," Dr. Kenyon says. "If they're not common, that tells you something about how they form or how they interact with the star over billions of years."

The modeling study grew out of work the two researchers were undertaking to figure out how the dwarf planet Pluto and its largest moon Charon manage to share space with four smaller moons that orbit the two larger objects. 

Pluto and Charon form a binary system that early in its history saw the two objects graze each other to generate a ring of dust that would become the additional moons.

The gravity the surrounding dust felt as Pluto and Charon swung about their shared center of mass would vary with clock-like precision.

Conventional wisdom held that this variable tug would trigger collisions at speeds too fast to allow the dust and larger chunks to merge into ever larger objects.

Kenyon and Dr. Bromley found that, in fact, the velocities would be smaller than people thought – no greater than the speeds would be around a single central object, where velocities are slow enough to allow the debris to bump gently and merge to build ever-larger objects.

They recognized that binary stars hosting planets are essentially scaled-up versions of the Pluto-Charon system. So they applied their calculations to a hypothetical binary star system with a circumstellar disk of dust and debris.

"The modest jostling in these orbits is the same modest jostling you'd get around a single star," Kenyon says, allowing rocky inner planets to form.

As for the Jupiter- or Neptune-scale planets found around binary stars, they would have formed farther out and migrated in over time, the researchers say, since there is too little material within the inner reaches of a circumstellar disk to build giant planets.

The duo's calculations imply that as more planets are discovered orbiting binary stars, a rising number of Tatooines will be among them. 

Tatooine "was science fiction," Kenyon says. But "it's not so far from science reality."

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Jupiter May Be Behind The Mysterious ‘Gaping Hole’ In Our Solar System

March 30, 2015 / / 0 Comments

Excerpt from huffingtonpost.comWhen astronomers began studying other solar systems in the Milky Way galaxy back in the 1990s, they noticed something peculiar: most of these systems have big planets that circle their host stars in tight orbits, a fin...

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New spin on Saturn’s peculiar, err, spin

March 27, 2015 / / 0 Comments

 Excerpt from spacedaily.comAccording to the new method, Saturn's day is 10 hours, 32 minutes and 44 seconds long. Tracking the rotation speed of solid planets, like the Earth and Mars, is a relatively simple task: Just measure the time it tak...

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NASA video illustrates ‘X-ray wind’ blasting from a black hole

March 27, 2015 / / 0 Comments

This artist's illustration shows interstellar gas, the raw material of star formation, being blown away.Excerpt from cnet.com It takes a mighty wind to keep stars from forming. Researchers have found one in a galaxy far, far away -- and NASA mad...

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Exoplanet Bonanza Boosts Count by 1,200

March 9, 2015 / / 0 Comments

Excerpt from news.discovery.comDozens of candidate worlds reside within the "habitable zones" of their parent stars. THE GIST - NASA's Kepler telescope has found more than 1,200 extrasolar planet candidates. - Smaller worlds, like Earth,...

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Far Flung Star Cluster Found at Milky Way’s Edge

March 8, 2015 / / 0 Comments

Astronomers in Brazil have discovered a cluster of stars forming at the edge of the Milky Way, according to a press release from the Royal Astronomical Society.




Excerpt from  news.discovery.com


This is unusual because it was believed that stars generally take form closer to the center of our spiral-shaped galaxy, rather than from its swirling, spiral arms, which are thousands of light-years away. These two clusters of stars — named Camargo 438 and 439 — were seen in a cloud at the galaxy’s outskirts.

Denilso Camargo, an astronomer at the Federal University of Rio Grande do Sul in Porto Alegre, Brazil, led a team that analyzed data from NASA’s orbiting Wide-Field Infrared Survey Explorer (WISE) observatory. They zeroed in on dense clumps of gas in so-called giant molecular clouds(GMCs) that are known to generate stars. GMCs are mainly located in the inner part of the galactic disc.

The new star clusters lie about 16,000 light-years away from the main disk of the Milky Way galaxy. How did they form there? The scientists aren’t yet sure but Camargo theorizes that one of two scenarios could have led to the stars’ formation.

In the first scenario, called the “chimney model,” supernovas could have flung the gas and dust that formed the cloud out of the Milky Way. Another explanation is the material could have drifted in from outside the galaxy.


“Our work shows that the space around the Galaxy is a lot less empty that we thought,” said Camargo. “The new clusters of stars are truly exotic.”

Camargo’s team published their results in the journal Monthly

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