Tag: pull (page 1 of 9)

Greg Giles ~ Breaking the Magician’s Code: The Secret to the Channeled Message Trick Revealed

January 17, 2016 / / 0 Comments

Growing up as a child I was fascinated by the master magicians and their amazing feats of prestidigitation and the incredible skill necessary to fool the eyes with conjure, coin or card. I performed my own magic shows in my basement for friends and fam...

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Report: No endangered animals in 200 zoos across the US!

May 17, 2015 / / 0 Comments




Excerpt from thenextdigit.com

On May 15, the 10th anniversary of Endangered Species Day has been kicked off across the United States, which sees a series of wildlife awareness events with the participation of over 200 zoos. These zoos across the country restricted access to a few of their endangered animals and birds to make visitors feel the non existence of such species.
Ohio’s Akron Zoo also participated in the awareness event, where it shrouded Sumatran tigers from visitors, with only limited access to visitors to capture a glimpse of the endangered tiger species. In Dallas Zoo, authorities kept the African penguins were kept away from visitors’ sight, while allowing those visitors who commit to eat sustainable seafood, switching off lights when not in use and such kind of conservation efforts.

Ohio’s Akron Zoo’s director of marketing and guest services David Barnhardt revealed that the zoo will be using this event to launch their own program SAFE (Saving Animals from Extinction) where the zoo will create awareness of saving endangered animals. SAFE is sponsored by the Association of Zoos and Aquariums. He also said,
“Through SAFE we will pull all of these resources we have available to us and develop action plans, raise awareness and engage the public to help these endangered species.”
Endangered Species Day is an opportunity for every humans to learn about the importance of animals, especially endangered species, and day to day actions they can take to protect these species, according to the Endangered Species Coalition. The Endangered Coalition not only sponsors events in the states, but also provides toolkits for zoos which interested in its own endangered species awareness programs such as SAFE.
Dallas Zoo has initiated a program in February 2015, named as the Wild Earth Academy, which educates people about endangered species. Ben Jones, Wild Earth Academy’s Senior Director and Dean, said in a statement:
“There’s a balance in nature and it’s very evident that that balance is becoming imbalanced, it’s shifting. We have to do our part to use the resources that we have, but not use them up.”
The Coalition also produces the yearly report “Vanishing: Ten American Species Our Children May Never See” – listing the top 10 most endangered species during the time of reporting. 2014’s ‘Vanishing’ report listed endangered animals like the Monarch butterfly, Mountain yellow-legged frog (extinct from southern Sierra Nevada), North Pacific right whale, great white shark (California/Mexico), little brown bat (extinct due to white-nose syndrome, an illness caused by a deadly fungus from Europe), whitebark pine, rusty patched bumblebee, greater sage-grouse, polar bear and snake river sockeye salmon.

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Take a Spaceship Journey to Arp. 273 ~ Hubble Zoom

May 16, 2015 / / 0 Comments

Arp 273 is a group of galaxies which interact with each other.  The constellation is 300 million light years away from Earth in the constellation Andromeda. The Andromeda galaxy is also located in the Andromeda constellation. The larger of th...

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10 Ways to Salvage a Bad Morning Before Parting Ways

May 12, 2015 / / 0 Comments

Excerpt from huffingtonpost.com1. Notice the good -- any and all good you can find -- even if it is simply, "I am so glad to see your face this morning," or, "You've always had a knack for unique clothing combinations!" 2. If someone is grumpy,...

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What astronomers learned when Messenger space probe crashed into Mercury

May 8, 2015 / / 0 Comments



Excerpt from statecolumn.com


On April 30, NASA concluded an historic voyage known as the Mercury Surface, Space Environment, Geochemistry and Ranging mission. The mission came to an end when the spacecraft carrying analytical instruments, Messenger, crashed into the planet’s surface after consuming all of its fuel.
The mission was far from a waste, however, as NASA rarely expects to see the majority of the spacecraft they launch ever again. According to Discovery, The probe sent back a spectacular photo of the surface of Mercury, using the craft’s Narrow Angle Camera in tandem with the Mercury Dual Imaging System. The photo shows a mile-wide view of the nearby planet’s surface in 2.1 meters per pixel resolution.
Right after the probe delivered the photo to NASA’s Deep Space Network, which is a collection of global radio antennae that tracks data on the agency’s robotic missions around the solar system, the signal was lost in what scientists assume was the craft’s final contact with the closest planet to the sun.
The four-year mission came to an end when the craft could no longer maintain its orbit around the solar system’s innermost planet due to lack of fuel. Mercury is just 36 miles from the sun, compared to Earth, which is 93 million miles away from the center of the solar system. Mercury is a peculiar world, with both frigid and extremely hot temperatures. Messenger also revealed that Mercury has a magnetic field similar to that of Earth’s, created by the motion of metallic fluids within the planet’s core.
The main challenge the Messenger mission faced was getting the space probe into orbit around Mercury. Due to the planet’s proximity to the sun, it was extremely difficult for flight engineers to avoid its gravitational pull. In addition to the challenge of catching Mercury’s comparatively weak gravitational force, high temperatures also made things tricky. Messenger was equipped with a sunshield designed to protect the spaceship cool on the side that faced the sun. NASA engineers also attempted to chart a long, elliptical orbit around Mercury, giving Messenger time to cool off as it rounded the backside of the planet.
Messenger made over 4,000 orbits around Mercury between 2011 and 2015, many more than the originally planned one-year mission would allow.
With the close-up shots of Mercury’s surface provided by Messenger, NASA scientists were able to detect trace signals of magnetic activity in Mercury’s crust. Using clues from the number of impact craters on the surface, scientists figured that Mercury’s magnetized regions could be as old as 3.7 billion years. Astronomers count the craters on a planet in order to estimate its age – the logic being that younger surfaces should have fewer impact sites than older surfaces.
The data sent back by Messenger has caused astronomers to reconsider their understanding of Mercury’s magnetic history. They now date the beginning of magnetism on Mercury to about 700 million years after the planet was formed. They cannot say for sure, however, if the magnetic field has been consistently active over this timeframe.
According to Messenger guest investigator Catherine Johnson, geophysicist at the University of British Columbia in Vancouver, that it was possible the magnetic field has been active under constant conditions, though she suspects it might also oscillate over time, like Earth’s. Information for the time period between 4 billion years ago and present day is sparse, though Johnson added that additional research is in the pipeline.
Johnson was pleased, however, with the insight offered into Mercury’s formation provided by these new magnetic clues. Magnetism on a planetary scale typically indicates a liquid metal interior. Since Mercury is so tiny, scientists originally believed that its center would be solid, due to the rate of cooling. The presence of liquid in the planet’s center suggests other materials’ presence, which would lower the freezing point. This suggests that a totally solid core would be unlikely.
Mercury’s magnetic field offers valuable insight into the formation of the planet, the solar system, and even the universe. Magnetism on Mercury indicates that it has a liquid iron core, according to Messenger lead scientist Sean Solomon of Columbia University.

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6 Natural Solutions To Decontaminate Soil

May 2, 2015 / / 0 Comments

Marco Torres, Prevent DiseaseWith a progressively educated population becoming more aware of the inherent dangers of the conventional food supply, urban farming has become hugely popular. However, more people are also becoming aware of contaminated soil and how heavy metals pose potential risks to their food crops. As backyard gardening continues to explode in popularity, we must ask how contaminated is our soil?Many municipalities in many countries are embracing urban agri [...]

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NASA’s Plan to Give the Moon a Moon

March 25, 2015 / / 0 Comments


arm-capture_0




Excerpt from wired.com

It sounds almost like a late ’90s sci-fi flick: NASA sends a spacecraft to an asteroid, plucks a boulder off its surface with a robotic claw, and brings it back in orbit around the moon. Then, brave astronaut heroes go and study the space rock up close—and bring samples back to Earth.
Except it’s not a movie: That’s the real-life idea for the Asteroid Redirect Mission, which NASA announced today. Other than simply being an awesome space version of the claw arcade game (you know you really wanted that stuffed Pikachu), the mission will let NASA test technology and practice techniques needed for going to Mars.
The mission, which will cost up to $1.25 billion, is slated to launch in December 2020. It will take about two years to reach the asteroid (the most likely candidate is a quarter-mile-wide rock called 2008 EV5). The spacecraft will spend up to 400 days there, looking for a good boulder. After picking one—maybe around 13 feet in diameter—it will bring the rock over to the moon. In 2025, astronauts will fly NASA’s still-to-be-built Orion to dock with the asteroid-carrying spacecraft and study the rock up close.
Although the mission would certainly give scientists an up-close opportunity to look at an asteroid, its main purpose is as a testing ground for a Mars mission. The spacecraft will test a solar electronic propulsion system, which uses the power from solar panels to pump out charged particles to provide thrust. It’s slower than conventional rockets, but a lot more efficient. You can’t lug a lot of rocket fuel to Mars.
Overall, the mission gives NASA a chance at practicing precise navigation and maneuvering techniques that they’ll need to master for a Mars mission. Such a trip will also require a lot more cargo, so grabbing and maneuvering a big space rock is good practice. Entering lunar orbit and docking with another spacecraft would also be helpful, as the orbit might be a place for a deep-space habitat, a rendezvous point for astronauts to pick up cargo or stop on their way to Mars.
And—you knew this part was coming, Armageddon fans—the mission might teach NASA something about preventing an asteroid from striking Earth. After grabbing the boulder, the spacecraft will orbit the asteroid. With the added heft from the rock, the spacecraft’s extra gravity would nudge the asteroid, creating a slight change in trajectory that NASA could measure from Earth. “We’re not talking about a large deflection here,” says Robert Lightfoot, an associate administrator at NASA. But the idea is that a similar technique could push a threatening asteroid off a collision course with Earth.
NASA chose this mission concept over one that would’ve bagged an entire asteroid. In that plan, the spacecraft would’ve captured the space rock by enclosing it in a giant, flexible container. The claw concept won out because its rendezvous and soft-landing on the asteroid will allow NASA to test and practice more capabilities in preparation for a Mars mission, Lightfoot says. The claw would’ve also given more chances at grabbing a space rock, whereas it was all or nothing with the bag idea. “It’s a one-shot deal,” he says. “It is what it is when we get there.” But the claw concept offers some choices. “I’ve got three to five opportunities to pull one of the boulders off,” he says. Not bad odds. Better than winning that Pikachu

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Scientist Claims to Discover Sounds of Stars

March 24, 2015 / / 0 Comments






Excerpt from clapway.com

If you can remember your primary school’s astronomy classes, the surface of a star is a very volatile place with tons of chemical reactions and extreme motions, and with immense gravitational pull. Generally a place you would not want to be. But researchers are now saying that if you were to orbit a star, it may be possible, with the right equipment, to hear what a star is saying! Or Singing?
Would you want to hear the sounds of stars?

The sound, unfortunately, is so high pitched that no mammal, not even a dolphin or bat, would be able to hear it, and couldn’t be heard anyway because space is a vacuum and there is no air medium for the sound to travel in.

With a frequency of nearly one trillion hertz, the sound was not only unexpected, but six million times higher than what any mammal can hear. But the researchers have developed a method to hear what they poetically refer to as “singing” or a star’s “song.”

Britain’s University of York’s researchers of hydrodynamics – the study of fluids in motion – fired a laser beam at the plasma in the laboratory and found that within a trillionth of a second, the plasma quickly moved from high-density to low-density areas.Plasma is a state of matter that makes up most things in the known universe and a few things on earth like lightning strikes and neon signs. It is basically a gas that has been charged with enough energy to loose the electrons from the atoms holding them together.

The spot where the low-density and high-density areas meet led to what the University researchers called a “traffic jam,” and resulted in an apparent sound wave, allowing us to know the sounds of stars.

Though this was achieved in the laboratory, scientists have yet to try to hear the sounds of a real star.

Dr. Pasley, a scientist from the Tata Institute of Fundamental Research in Mumbai, India, , said: “One of the few locations in nature where we believe this effect would occur is at the surface of stars. When they are accumulating new material stars could generate sound in a very similar manner to that which we observed in the laboratory–so the stars might be singing–but since sound cannot propagate through the vacuum of space, no-one can hear them.”

The technique used to observe the sound waves in the laboratory sort of works like a police speed camera, allowing scientists to accurately measure how the fluid would sound at the point of being struck by the laser at very minute timescales. The research was published in Physical Review Letters.

Perhaps in the future we might be able to listen in on the sounds of stars instead of just viewing it, and hear what they have to say!

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Young Jupiter wiped out solar system’s early inner planets, study says

March 24, 2015 / / 0 Comments


Ganymede
(Photo : NASA/ESA) In early days of solar system, Jupiter destroyed everything that came in its way, researchers have found.


Excerpt from latimes.com

Before Mercury, Venus, Earth and Mars occupied the inner solar system, there may have been a previous generation of planets that were bigger and more numerous – but were ultimately doomed by Jupiter, according to a new study.

If indeed the early solar system was crowded with so-called super-Earths, it would have looked a lot more like the planetary systems found elsewhere in the galaxy, scientists wrote Monday in the Proceedings of the National Academy of Sciences.


Inner planets
As NASA’s Kepler space telescope has found more than 1,000 planets in orbit around other stars, along with more than 4,000 other objects that are believed to be planets but haven’t yet been confirmed. Kepler finds these planets by watching their host stars and registering tiny drops in their brightness – a sign that they are being ever-so-slightly darkened by a planet crossing in front of them.

In addition, ground-based telescopes have detected hundreds of exoplanets by measuring the wiggles of distant stars. Those stars wiggle thanks to the gravitational pull of orbiting planets, and the Doppler effect makes it possible to estimate the size of these planets.

The more planetary systems astronomers discovered, the more our own solar system looked like an oddball. Exoplanets – at least the ones big enough for us to see – tended to be bigger than Earth, with tight orbits that took them much closer to their host stars. In multi-planet systems, these orbits tended to be much closer together than they are in our solar system. For instance, the star known as Kepler-11 has six planets closer to it than Venus is to the sun.

Why does our solar system look so different? Astrophysicists Konstantin Batygin of Caltech and Greg Laughlin of UC Santa Cruz summed it up in one word: Jupiter.

Here’s what could have happened, according to their models:

In Solar System 1.0, the region closest to the sun was occupied by numerous planets with masses several times bigger than that of Earth. There were also planetesimals, “planetary building blocks” that formed within the first million years after the birth of the sun, Batygin and Laughlin wrote.

This is how things might have stayed if the young Jupiter had stayed put at its initial orbit, between 3 and 10 astronomical units away from the sun. (An astronomical unit, or AU, is the distance between the Earth and the sun. Today, Jupiter’s orbit ranges between 5 and 5.5 AUs from the sun.)

But Jupiter was restless, according to a scenario known as the “Grand Tack.” In this version of events, Jupiter was swept up by the currents of gas that surrounded the young sun and drifted toward the center of the solar system.

Jupiter, however, was too big to travel solo. All manner of smaller objects would have been dragged along too. With so many bodies in motion, there would have been a lot of crashes.

The result was “a collisional cascade that grinds down the planetesimal population to smaller sizes,” the astrophysicists wrote. For the most part, these planetary crumbs were swept toward the sun and ultimately destroyed, like disintegrating satellites falling back to Earth.

The planetesimals wouldn’t have been Jupiter’s only victims. Assuming the early solar system resembled the planetary systems spied by Kepler and other telescopes, there would have been “a similar population of first-generation planets,” the pair wrote. “If such planets formed, however, they were destroyed.”

Jupiter probably got about as close to the sun as Mars is today before reversing course, pulled away by the gravity of the newly formed Saturn. That would have ended the chaos in the inner solar system, allowing Earth and the other rocky planets to form from the debris that remained.

“This scenario provides a natural explanation for why the inner Solar System bears scant resemblance to the ubiquitous multi-planet systems” discovered by Kepler and other survey efforts, Batygin and Laughlin wrote.

Although their models show that this is what might have happened, they don’t prove that it actually did. But there may be a way to get closer to the truth.

The scientists’ equations suggest that if a star is orbited by a cluster of close-in planets, there won’t be a larger, farther-out planet in the same system. As astronomers find more exoplanetary systems, they can see whether this prediction holds up.

Also, if far-away solar systems are experiencing a similar series of events, telescopes ought to be able to detect the extra heat thrown off by all of the planetesimal collisions, they added.

Sadly for those hoping to find life on other planets, the pair’s calculations also imply that most Earth-sized planets are lacking in water and other essential compounds that can exist in liquid or solid form. As a result, they would be “uninhabitable,” they wrote.

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Milky Way Galaxy May Be 50 Percent Bigger Than We Thought

March 11, 2015 / / 0 Comments

 Excerpt from cbsnews.com Rings of stars thought to surround the Milky Way are actually part of it, according to new research, meaning the galaxy is bigger than previously believed.The findings extend the known width of the Milk...

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Earth’s address within a massive supercluster of 100,000 galaxies ~ Video

March 11, 2015 / / 0 Comments





Excerpt from cnet.com


Astronomers have mapped the Milky Way's position to the outskirts of a supercluster of galaxies, newly dubbed Laniakea, meaning "Immense Heaven".

The distribution of galaxies throughout the universe is not more-or-less even; instead, galaxies tend to cluster together, bound together by the pull of each other's gravity. These groups can be a variety of sizes. The Milky Way Galaxy, for instance, is part of what is called the Local Group, which contains upwards of 54 galaxies, covering a diameter of 10 megalight-years (10 million light-years).

Click to zoom

But this Local Group is just a small part of a much, much bigger structure, which researchers at the University of Hawai'i Mānoa have now mapped in detail. Coming in at over 100,000 galaxies, the massive supercluster has been given the name Laniakea -- "immense heaven" in Hawaiian.
The new 3D map was created by examining the positions and movements of the 8000 closest galaxies to the Milky Way. After calculating which galaxies were being pulled away from us and which were being pulled towards us -- accounting for the universe's expansion -- the team, led by astronomer R. Brent Tully, was able to map the paths of galactic migration -- and define the boundaries of Laniakea.

Traditionally, the borders of galactic superclusters have been difficult to map, but studying the gravitational force acting on our neighbouring galaxies has provided some important clues. All objects inside Laniakea are being slowly but surely drawn to a single point -- a force known as the Great Attractor, a gravitational anomaly with a mass tens of thousands of times the mass of the Milky Way.

Everything that is being pulled towards the Great Attractor is part of Laniakea -- although it's possible that Laniakea itself might in turn be part of a structure that is larger still.

"We probably need to measure to another factor of three in distance to explain our local motion," Tully said. "We might find that we have to come up with another name for something larger than we're a part of -- we're entertaining that as a real possibility."

The full paper, "The Laniakea supercluster of galaxies", can be read online in the journal Nature.

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Warp in spacetime lets astronomers watch the same star explode four times

March 8, 2015 / / 0 Comments



Excerpt from csmonitor.com

Thanks to a phenomenon known as gravitational lensing, the Hubble Space Telescope has captured four images of the same supernova explosion.

For the first time, a cosmic magnifying glass has allowed scientists to see the same star explosion four times, possibly offering a revealing glimpse into these explosive stellar deaths and the nature of the accelerating universe.

Astronomers using the Hubble Space Telescope have captured four images of a supernova explosion in deep space thanks to a galaxy located between Earth and the massive star explosion. You can see how Hubble saw the supernova in this NASA video. The galaxy cluster warped the fabric of space and time around it — like a bowling ball placed on a bed sheet — allowing scientists to see the supernova in four images.

"It was predicted 50 years ago that a supernova could be gravitationally lensed like this, but it's taken a long time for someone to find an example," lead study author Patrick Kelly, an astronomer at the University of California, Berkeley told Space.com. "It's fun to have been able to find the first one." 

The supernova, which was discovered on Nov. 11, 2014, is located about 9.3 billion light-years away from Earth, near the edge of the observable universe. The researchers have named the distant supernova SN Refsdal in honor of the late Norwegian astrophysicist Sjur Refsdal, a pioneer of gravitational lensing studies. Due to gravitational lensing, "the supernova appears 20 times brighter than its normal brightness," study co-author Jens Hjorth, head of the Dark Cosmology Centre at the Niels Bohr Institute at the University of Copenhagen, said in a statement.
The lensing galaxy, which is about 5 billion light-years from Earth, is part of a large cluster of galaxies known MACS J1149.6+2223. In 2009, astronomers discovered that this cluster was the source of the largest known image of a spiral galaxy ever seen through a gravitational lens.

The four images of the supernova each appeared separately over the course of a few weeks. This is because light can take various paths around and through a gravitational lens, arriving at Earth at different times.

Using gravity as a lens

Gravity is created when matter warps the fabric of reality. The greater the mass of an object, the more space-time curves around that object and the stronger its gravitational pull, the discovery enshrined in Einstein's theory of general relativity, which celebrates its centennial this year.

As a result, gravity can also bend light like a lens, meaning objects see n behind powerful gravitational fields, such as those of massive galaxies, are magnified. Gravitational lensing was first discovered in 1979, and today gravitational lenses can help astronomers see features otherwise too distant and faint to detect with even the largest telescopes.

"These gravitational lenses are like a natural magnifying glass. It's like having a much bigger telescope," Kelly said in a statement. "We can get magnifications of up to 100 times by looking through these galaxy clusters."

When light is far from a gravitationally lensing mass, or if the gravitationally lensing mass is not especially large, only "weak lensing" occurs, barely distorting the light. However, when the light comes from almost exactly behind the gravitationally lensing mass, "strong lensing" can happen. 

When a strongly lensed object occupies a large patch of space — for instance, if it's a galaxy — it can get smeared into an "Einstein ring" surrounding a gravitationally lensing mass. However, strong lensing of small, pointlike items — for instance, super-bright objects known as quasars — often produces multiple images surrounding the gravitationally lensing mass, resulting in a so-called "Einstein cross."

The observations of SN Refsdal mark the first time astronomers on Earth have witnessed strong lensing of a  supernova, with four images of an exploding star arrayed as an Einstein cross.

An expanding universe

These new findings could help scientists measure the accelerating rate at which the universe is expanding, researchers say.

A computer model of the lensing cluster suggests the scientists missed chances to see the lensed supernova 50 and 10 years ago. However, the model also suggests more images of the explosion will repeat again within the next 10 years.

The timing of when all these images of the supernova arrive depends on the gravitational pull of the matter generating the gravitational lens. So, by measuring those times, the researchers hope to map how visible normal matter and invisible dark matter is distributed in the lensing galaxy.

Dark matter is currently one of the greatest mysteries in science, a poorly understood substance thought to make up five-sixths of all matter in the universe. A better understanding of how dark matter is behaving in this gravitationally lensing cluster might help shed light on the material's nature, Kelly said.

Analyzing when the images arrive could also help scientists pinpoint the rate at which the universe is expanding. Although there are already several ways to measure the cosmic expansion rate, "there has been a lot of heated debate between different methods, so it'd be interesting to see how this new technique might affect the area," Kelly said. "It's always nice to have completely independent measurements of the same quantity."

The scientists detailed their findings in the March 6 issue of the journal Science.

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Cluster Filled with Dark Matter May House ‘Failed Galaxies’

February 21, 2015 / / 0 Comments

The Coma Cluster


Excerpt space.com

 A strange set of 48 galaxies appears to be rich in dark matter and lacking in stars, suggesting that they may be so-called "failed" galaxies, a new study reports.

The galaxies in question are part of the Coma Cluster, which lies 300 million light-years from Earth and packs several thousand galaxies into a space just 20 million light-years across. To study them, Pieter van Dokkum of Yale University and his colleagues used the Dragonfly Telephoto Array in New Mexico.

The array's eight connected Canon telephoto lenses allow the researchers to search for extremely faint objects that traditional telescope surveys miss. Often, such as when the researchers used the array to search for the faint glow that dark matter might create, the hunt comes up empty. 


But when van Dokkum and his colleagues looked toward the Coma Cluster, they found a pleasant surprise.

"We noticed all these faint little smudges in the images from the Dragonfly telescope," van Dokkum told Space.com.

The mysterious blobs nagged at van Dokkum, compelling him to look into the objects further. Fortuitously, NASA's Hubble Space Telescope had recently captured one of these objects with its sharp eye. 

"It turned out that they're these fuzzy blobs that look somewhat like dwarf spheroidal galaxies around our own Milky Way," van Dokkum said. "So they looked familiar in some sense … except that if they are at the distance of the Coma Cluster, they must be really huge."

And with very few stars to account for the mass in these galaxies, they must contain huge amounts of dark matter, the researchers said. In fact, to stay intact, the 48 galaxies must contain 98 percent dark matter and just 2 percent "normal" matter that we can see. The fraction of dark matter in the universe as a whole is thought to be around 83 percent. 

But before making this claim, the team had to verify that these blobs really are as distant as the Coma Cluster. (In fact, the team initially thought the galaxies were much closer.). But even in the Hubble image the stars were not resolved. If Hubble — one of the most powerful telescopes in existence — can't resolve the stars, those pinpricks of light must be pretty far away, study team members reasoned. 

Now, van Dokkum and his colleagues have definitive evidence: They've determined the exact distance to one of the galaxies. The team used the Keck Telescope in Hawaii to look at one of the objects for two hours. This gave them a hazy spectrum, from which they were able to tease out the galaxy's recessional velocity — that is, how fast it is moving away from Earth.

That measure traces back to the Hubble Telescope's namesake. In 1929, American astronomer Edwin Hubble discovered one of the simplest and most surprising relationships in astronomy: The more distant a galaxy, the faster it moves away from the Milky Way.

Today, astronomers use the relationship to measure a galaxy's recessional velocity and thus calculate the galaxy's distance. In this case, the small fuzzy blob observed with Keck was moving away from Earth at 15.7 million mph (25.3 million km/h). That places it at 300 million light-years away from Earth, the distance of the Coma Cluster.

So the verdict is officially in: These galaxies must be associated with the Coma Cluster and therefore must be extremely massive.
"It looks like the universe is able to make unexpected galaxies," van Dokkum said, adding that there is an amazing diversity of massive galaxies.

But the clusters still present a mystery: The team doesn't know why they have so much dark matter and so few stars.

Though they look serene and silent from our vantage on Earth, stars are actually roiling balls of violent plasma. Test your stellar smarts with this quiz.
One possibility is that these are "failed" galaxies. A galaxy's first supernova explosions will drive away huge amounts of gas. 

Normally, the galaxy has such a strong gravitational pull that most of the expelled gas falls back onto the galaxy and forms the next generations of stars. But maybe the strong gravitational pull of the other galaxies in the Coma Cluster interfered with this process, pulling the gas away.

"If that happened, they had no more fuel for star formation and they were sort of stillborn galaxies where they started to get going but then failed to really build up a lot of stars," said van Dokkum, adding that this is the most likely scenario. 

Another possibility is that these galaxies are in the process of being ripped apart. But astronomers expect that if this were the case, the galaxies would be distorted and streams of stars would be flowing away from them. Because these effects don't appear, this scenario is very unlikely.

The next step is to try to measure the individual motions of stars within the galaxies. If the team knew those stars' speeds, it could calculate the galaxies' exact mass, and therefore the amount of dark matter they contain. If the stars move faster, the galaxy is more massive. And if they move slower, the galaxy is less massive. 
However, this would require a better spectrum than the one the team has right now.

"But it's not outside the realm of what's possible," van Dokkum assured. "It's just very hard."

The original study has been published in Astrophysical Journal Letters. You can read it for free on the preprint site arXiv.org.

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