Date: October 18, 2014

Our Milky Way strips nearby galaxies of star-forming hydrogen

October 18, 2014 / / 0 Comments


Artist's impression of the Milky Way. Its hot halo appears to be stripping away the star-forming atomic hydrogen from its companion dwarf spheroidal galaxies. Image credit: NRAO/AUI/NSF
Artist’s impression of the Milky Way. Its hot halo appears to be stripping away the star-forming atomic hydrogen from its companion dwarf spheroidal galaxies. Image credit: NRAO/AUI/NSF

Excerpt from
earthsky.org

Astronomers have discovered that our nearest galactic neighbors are devoid of star-forming gas, and that our Milky Way is to blame.

New observations by large radio telescopes reveal that within a well-defined boundary around our galaxy, dwarf galaxies are completely devoid of hydrogen gas. Beyond this point, dwarf galaxies are teeming with star-forming material. 

The Milky Way galaxy is actually the largest member of a compact clutch of galaxies that are bound together by gravity. Swarming around our home galaxy is a menagerie of smaller dwarf galaxies, the smallest of which are the relatively nearby dwarf spheroidals, which may be the leftover building blocks of galaxy formation.

Further out are a number of similarly sized and slightly misshaped dwarf irregular galaxies, which are not gravitationally bound to the Milky Way and may be relative newcomers to our galactic neighborhood.

Kristine Spekkens is an assistant professor at the Royal Military College of Canada and lead author on a paper published in the Astrophysical Journal Letters. She said:
"Astronomers wondered if, after billions of years of interaction, the nearby dwarf spheroidal galaxies have all the same star-forming ‘stuff’ that we find in more distant dwarf galaxies."

Previous studies have shown that the more distant dwarf irregular galaxies have large reservoirs of neutral hydrogen gas, the fuel for star formation. These past observations, however, were not sensitive enough to rule out the presence of this gas in the smallest dwarf spheroidal galaxies. 

Spekkens said:
"What we found is that there is a clear break, a point near our home galaxy where dwarf galaxies are completely devoid of any traces of neutral atomic hydrogen."
 Bottom line: New observations by large radio telescopes reveal that within a well-defined boundary around our galaxy, dwarf galaxies are completely devoid of star-making hydrogen gas. Astronomers say our Milky Way is to blame.

Known Milky Way satellite galaxies. Click here for more about this diagram.
Neighboring galaxies to our own Milky Way (Descriptions below)
 

NAME DISTANCE (kpc) DISCOVERY PAPER
Canes Major 7.2Martin et al. 2004, A dwarf galaxy remnant in Canis Major: the fossil of an in-plane accretion on to the Milky Way
Segue 317 Belokurov et al. 2010, Big Fish, Little Fish: Two New Ultra-Faint Satellites of the Milky Way
Segue 123 Belokurov et al. 2007, Cats and Dogs, Hair and A Hero: A Quintet of New Milky Way Companions
Sagittarius24Ibata, Gilmore & Irwin, 1994, A dwarf satellite galaxy in Sagittarius 1995, Sagittarius: the nearest dwarf galaxy
Segue 234.7 Belokurov et al. 2009, The discovery of Segue 2: a prototype of the population of satellitesof satellites
Bootes II 43 Walsh, Jerjen & Willman, 2007, A Pair of Bootes: A New Milky Way Satellite
Coma 44 Belokurov et al. 2007, Cats and Dogs, Hair and A Hero: A Quintet of New Milky Way Companions
Willman 1 (SDSSJ1049+5103) 45Willman et al. 2005, A New Milky Way Companion: Unusual Globular Cluster or Extreme Dwarf Satellite?
Bootes III 46Grillmair 2009, Four New Stellar Debris Streams in the Galactic Halo
LMC 50.8-
SMC 59.7-
Bootes 60 Belokurov et al. 2006, A Faint New Milky Way Satellite in Bootes
Ursa Minor 66A.G. Wilson of the Lowell Observatory in 1955, Sculptor-Type Systems in the Local Group of Galaxies
Sculptor (Scl) 79discovered in 1938 by Harlow Shapley, A Stellar System of a New Type
Draco 82 A.G. Wilson of the Lowell Observatory in 1955, Sculptor-Type Systems in the Local Group of Galaxies
Sextans 89 Mike Irwin, M.T. Bridgeland, P.S. Bunclark and R.G. McMahon, 1990 A new satellite galaxy of the Milky Way in the constellation of Sextans
Ursa Major (UMa) 100Willman et al. 2005, A New Milky Way Dwarf Galaxy in Ursa Major
Carina 103Cannon, R. D., Hawarden, T. G., & Tritton, S. B., 1977, A new Sculptor-type dwarf elliptical galaxy in Carina
Hercules 140 Belokurov et al. 2007, Cats and Dogs, Hair and A Hero: A Quintet of New Milky Way Companions
Fornax 140discovered in 1938 by Harlow Shapley, described in "Two Stellar Systems of a New Kind", Nature, Vol. 142, p. 715
Canes Venatici II 150 Sakamoto & Hasegawa 2006, Discovery of a Faint Old Stellar System at 150 kpc
Leo IV 160 Belokurov et al. 2007, Cats and Dogs, Hair and A Hero: A Quintet of New Milky Way Companions
Pisces II 182 Belokurov et al. 2010, Big Fish, Little Fish: Two New Ultra-Faint Satellites of The Milky Way
Leo II (Leo B) 208 Robert G. Harrington and Albert George Wilson, 1950, Two New Stellar Systems in Leo
Canes Venatici 220Zucker et al. 2006 A New Milky Way Dwarf Satellite in Canes Venatici
Leo I 254 Robert G. Harrington and Albert George Wilson, 1950, Two New Stellar Systems in Leo

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MARY MAGDALENE: The Power of the Gospels

October 18, 2014 / / 0 Comments

Received by Mercedes Kirkel On July 28, 2014 Question: Would the revelation of the gospels, which you and Yeshua may have written, give insight we are lacking into the coming together of the Masculine and Feminine? Mary Magdalene: It has largely been lost in terms of the verbal communication. But there was an empowerment in that […]

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Deconstructing the Ebola Agenda

October 18, 2014 / / 0 Comments

Zen Gardner, GuestWaking TimesIt looks like we’re going to be saddled with this ebola roll-out for a while. It seems to be working according to plan as the public jumps on the fear bandwagon and all kinds of media reports are taken at face value regarding what’s going on. A very easy environment to manipulate public sentiment, emotions and responses which is their favorite milieu.The old problem – reaction – solution game.I don’t like dwelling on this su [...]

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The Production Of The Story Of A Course In Miracles Workbook Lessons 91 – 92

October 18, 2014 / / 0 Comments

The Production Of The Story Of A Course In Miracles Workbook Lessons 91 - 92Workbook Lessons 91 - 92www.themasterteacher.tv

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Researchers show Earth’s magnetic reversal occurs faster than previously thought

October 18, 2014 / / 0 Comments



Excerpt from dailycal.org
By Suhauna Hussain | Staff

A study by researchers from UC Berkeley, Columbia University, Italy and France shows that the most recent reversal of Earth’s magnetic field occurred in fewer than 100 years, which is much more rapidly than previously believed.

A magnetic field reversal is when the Earth’s magnetic poles are switched – a phenomenon that has occurred many times in history. Magnetic fields usually remain at a certain intensity but weaken significantly before reversing.

Previously, researchers believed reversals occurred over thousands of years. The discovery that reversals can happen in such a short time is significant because it can help scientists further understand how magnetic reversals behave.

In the most recent magnetic reversal, the Earth’s field reversed a few times over several thousand years before it finally “snapped,” making its final reversal into its current orientation in fewer than 100 years, Renne said.

Researchers don’t have clear-enough records of other reversals to know whether this behavior is normal, he added.

Bruce Buffett, campus earth and planetary sciences chair and professor, unaffiliated with the project, questioned the study’s definition of a reversal, arguing that a complete magnetic reversal takes much longer.

According to Buffett, it’s true that the field can switch direction within 100 years, but when that rapid switch occurs, the field is still relatively weak. It actually takes thousands of years for the field to regain its normal intensity in its reversed direction, he said.
“I can tell you that a reversal can’t (take) place in a 100 years, but something that goes from very weak to very weak in another direction can take place in that amount of time,” Buffett said.

Yet the study was “remarkable” for obtaining such a detailed and accurate record, he said.

Moving forward, the researchers will continue the study and further analyze sediment samples.

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Some like it hot ~ NASA Stumbles Upon A Dead Star That’s 10 Million Times Brighter Than The Sun

October 18, 2014 / / 0 Comments


bright star
This image of the super-bright pulsar (shown here in magenta) was made using observational data from three telescopes, including NASA’s NuSTAR.



Excerpt from
huffingtonpost.com

Think our sun is bright? NASA says its NuSTAR space-based X-ray telescope has detected a dead star that pumps out as much energy as 10 million suns.

"You might think of this pulsar as the 'Mighty Mouse' of stellar remnants," Dr. Fiona A. Harrison, professor of physics and astronomy at the California Institute of Technology in Pasadena and the principal investigator of the NuSTAR mission, said in a written statement.



The super-bright pulsar--the brightest ever recorded--is located about 12 million light-years from Earth in the Messier 82 galaxy. It's an example of a class of mysterious celestial objects known as ultraluminous X-ray sources, or ULXs.

"We took it for granted that the powerful ULXs must be massive black holes," Dr. Matteo Bachetti, an astrophysicist at the University of Toulouse in France and the lead author of a new study about the pulsar, said in the statement.

The X-rays are believed to be generated by the material as it heats up while falling into a dense object, in this case a pulsar.

"How much visible light is emitted is actually an interesting thing to know," Bachetti told The Huffington Post in an email.

In any case, the surprising discovery has scientists scratching their heads.

"This is going to challenge theorists and pave the way for a new understanding of the diversity of these fascinating objects," Dr. Jeanette Gladstone, a University of Alberta astronomer who wasn't involved in the research, said in the statement.

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Mysterious X-37B Space Plane Returns to Earth After Nearly Two Years

October 18, 2014 / / 0 Comments



Excerpt from nbcnews.com

By Devin Coldewey

No one seems to know much about the Air Force's X-37B secret space plane except that it appears to be working exactly as designed. The unmanned Boeing-built craft, which resembles a miniature space shuttle, returned to Earth on Friday after nearly two years — 674 days, to be exact — in space. It's the X-37B program's third mission to space and by far the longest.

The plane landed at 9:24 a.m. local time on Oct. 17 at Vandenberg Air Force Base in California, the Air Force's 30th Space Wing announced. 

"The 30th Space Wing and our mission partners, Air Force Rapid Capabilities Office, Boeing, and our base support contractors, have put countless hours of hard work into preparing for this landing and today we were able to see the culmination of that dedication," Colonel Keith Balts, 30th Space Wing commander, said in a release. "I'm extremely proud of our team for coming together to execute this third safe and successful landing. Everyone from our on console space operators to our airfield managers and civil engineers take pride in this unique mission and exemplify excellence during its execution." 

But just what did the X-37B do up there? Officially, the Air Force isn't telling. 

What is known is that the X-37B has no human pilot, or at least not one in its windowless cockpit. It's operated remotely and lands on its own.

The plane's size means there isn't room on board for much except avionics equipment, fuel for the thrusters, and a mysterious cavity about the size of a truck bed that could contain all manner of sensors, experiments, hardware — perhaps some bacterial colonies, or a bomb. No one can be sure what's inside.

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Saturn’s ‘Death Star’ moon could harbor a secret ocean

October 18, 2014 / / 0 Comments

Mimas, Saturn's 'Death Star' moon
Scientists say Saturn's "Death Star" moon, Mimas, has a strange wobble that could indicate it has an elongated core -- or that it's hiding a subsurface ocean. (JPL/NASA)

Excerpt from
latimes.com 
By Amina Khan contact the reporter

When it comes to Saturn’s moons, water-squirting Enceladus and the hydrocarbon lakes of Titan typically steal the spotlight. But now, scientists think that lesser-known Mimas may be harboring a strange secret of its own. Scientists who studied the ‘Death Star’ moon with NASA’S Cassini spacecraft have discovered a weird wobble in its motions that could mean one of two things: Either Mimas has an oddly elongated core, or it’s hiding an ocean inside its icy body.
The findings, described in the journal Science, shed new light on a mysterious but often-overlooked moon that could hold clues to its early formation.

Mimas is an icy moon that’s 246 miles wide and whose most distinctive feature is the 88-mile-wide Herschel crater – a giant Cyclops-like indentation that makes the moon resemble the planet-obliterating superweapon from "Star Wars" that's known as the Death Star.
But the scientists noticed something strange – the moon seemed to be wobbling, or “librating,” about twice as much as they expected. After going through several different explanations, they settled on two main possibilities. Either this round moon has a football-shaped core that’s causing the wobble, or there’s a liquid water ocean underneath the icy surface.
If Mimas holds an ocean, it joins an elite group of moons (including Enceladus as well as Jupiter's moon Europa) that potentially hold liquid water – which is key for the search for other worlds besides Earth with life-hosting potential.

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