 |
|
First detection of magnetic field in distant galaxy produces a surprise
October 02, 2008Using a powerful radio telescope to peer into the early universe, a team of California astronomers has obtained the first direct measurement of a nascent galaxy's magnetic field as it appeared 6.5 billion years ago.
Astronomers believe the magnetic fields within our own Milky Way and other nearby galaxies-which control the rate of star formation and the dynamics of interstellar gas--arose from a slow "dynamo effect." In this process, slowly rotating galaxies are thought to have generated magnetic fields that grew very gradually as they evolved over 5 billion to 10 billion years to their current levels.
But in the October 2 issue of Nature, the astronomers report that the magnetic field they measured in this distant "protogalaxy" is at least 10 times greater than the average value in the Milky Way.
"This was a complete surprise," said Arthur Wolfe, a professor of physics at UC San Diego's Center for Astrophysics and Space Sciences who headed the team. "The magnetic field we measured is at least an order of magnitude larger than the average value of the magnetic field detected in our own galaxy."
The astronomers from the University of California campuses at Berkeley, San Diego and Santa Cruz used the world's largest fully steerable radio telescope for their measurements-the Robert C. Byrd Green Bank Telescope in Green Bank, West Virginia operated by the National Science Foundation's National Radio Astronomy Observatory. The young protogalaxy they probed, DLA-3C286, is located in a region of the northern sky that is directly overhead during the spring.
Until recently, astronomers knew very little about magnetic fields outside our own galaxy, having directly measured the magnetic field in only one nearby galaxy. "And that field wasn't as strong as the field we saw," said Wolfe.
But a team of Swiss and American astronomers reported in the July 17 issue of Nature that an indirect measurement of the magnetic fields of 20 distant galaxies, using the bright light from quasars, suggests that the magnetic fields of young galaxies were as strong when the universe was only a third of its current age as they are in the mature galaxies today.
Wolfe said those indirect measurements and his team's latest direct measurement of a distant galaxy's magnetic field "do not necessarily cast doubt on the leading theory of magnetic field generation, the mean-field-dynamo model, which predicts that the magnetic field strengths should be much weaker in galaxies in the cosmological past."
"Our results present a challenge to the dynamo model, but they do not rule it out," he added. "Rather the strong field that we detect is in gas with little if no star formation, and an interesting implication is that the presence of the magnetic fields is an important reason why star formation is very weak in these types of protogalaxies."
Wolfe said his team has two other plausible explanations for what they observed. "We speculate that either we are seeing a field toward the central regions of a massive galaxy, since magnetic fields are known to be larger towards the centers of nearby galaxies. It is also possible that the field we detect has been amplified by a shock wave generated by the collision between two galaxies."
"In either case," he added, "our detection indicates that magnetic fields may be important factors in the evolution of galaxies, and in particular may be responsible for the low star formation rates detected throughout the gaseous progenitors of young galaxies in the early universe."
"The challenge now," said J. Xavier Prochaska, another member of the team who is a professor of astronomy at UC Santa Cruz, "is to perform observations like these on galaxies throughout the universe."
University of California - San Diego
"This was a complete surprise," said Arthur Wolfe, a professor of physics at UC San Diego's Center for Astrophysics and Space Sciences who headed the team. "The magnetic field we measured is at least an order of magnitude larger than the average value of the magnetic field detected in our own galaxy."
The astronomers from the University of California campuses at Berkeley, San Diego and Santa Cruz used the world's largest fully steerable radio telescope for their measurements-the Robert C. Byrd Green Bank Telescope in Green Bank, West Virginia operated by the National Science Foundation's National Radio Astronomy Observatory. The young protogalaxy they probed, DLA-3C286, is located in a region of the northern sky that is directly overhead during the spring.
Until recently, astronomers knew very little about magnetic fields outside our own galaxy, having directly measured the magnetic field in only one nearby galaxy. "And that field wasn't as strong as the field we saw," said Wolfe.
But a team of Swiss and American astronomers reported in the July 17 issue of Nature that an indirect measurement of the magnetic fields of 20 distant galaxies, using the bright light from quasars, suggests that the magnetic fields of young galaxies were as strong when the universe was only a third of its current age as they are in the mature galaxies today.
Wolfe said those indirect measurements and his team's latest direct measurement of a distant galaxy's magnetic field "do not necessarily cast doubt on the leading theory of magnetic field generation, the mean-field-dynamo model, which predicts that the magnetic field strengths should be much weaker in galaxies in the cosmological past."
"Our results present a challenge to the dynamo model, but they do not rule it out," he added. "Rather the strong field that we detect is in gas with little if no star formation, and an interesting implication is that the presence of the magnetic fields is an important reason why star formation is very weak in these types of protogalaxies."
Wolfe said his team has two other plausible explanations for what they observed. "We speculate that either we are seeing a field toward the central regions of a massive galaxy, since magnetic fields are known to be larger towards the centers of nearby galaxies. It is also possible that the field we detect has been amplified by a shock wave generated by the collision between two galaxies."
"In either case," he added, "our detection indicates that magnetic fields may be important factors in the evolution of galaxies, and in particular may be responsible for the low star formation rates detected throughout the gaseous progenitors of young galaxies in the early universe."
"The challenge now," said J. Xavier Prochaska, another member of the team who is a professor of astronomy at UC Santa Cruz, "is to perform observations like these on galaxies throughout the universe."
University of California - San Diego
Magnetic Field Current Events and Magnetic Field News RSSNew study confirms exotic electric properties of graphene
First, it was the soccer-ball-shaped molecules dubbed buckyballs. Then it was the cylindrically shaped nanotubes. Now, the hottest new material in physics and nanotechnology is graphene: a remarkably flat molecule made of carbon atoms arranged in hexagonal rings much like molecular chicken wire.
New explanation for nature's hardiest life form
Got food poisoning? The cause might be bacterial spores, en extremely hardy survival form of bacteria, a nightmare for health care and the food industry and an enigma for scientists.
A bubbling ball of gas
The Sun is a bubbling mass. Packages of gas rise and sink, lending the sun its grainy surface structure, its granulation. Dark spots appear and disappear, clouds of matter dart up - and behind the whole thing are the magnetic fields, the engines of it all.
German high-school students involved in an astronomical research project
This week, Astronomy & Astrophysics publishes a somewhat unusual research article because it is co-authored by German high-school students.
New TMS clinic offers noninvasive treatment for major depression
Rush University Medical Center has opened the Transcranial Magnetic Stimulation (TMS) Clinic to offer patients suffering from major depression a safe, effective, non-drug treatment.
Carbon atmosphere discovered on neutron star
Evidence for a thin veil of carbon has been found on the neutron star in the Cassiopeia A supernova remnant. This discovery, made with NASA's Chandra X-ray Observatory, resolves a ten-year mystery surrounding this object.
High-performance plasmas may make reliable, efficient fusion power a reality
In the quest to produce nuclear fusion energy, researchers from the DIII-D National Fusion Facility have recently confirmed long-standing theoretical predictions that performance, efficiency and reliability are simultaneously obtained in tokamaks, the leading magnetic confinement fusion device, operating at their performance limits.
A special issue on the International Workshop of the 2008 Solar Total Eclipse
On August 1, 2008 a total solar eclipse was visible within a narrow corridor that traversed from North America to China.
Magnetic mixing creates quite a stir
Sandia researchers have developed a process that can mix tiny volumes of liquid, even in complicated spaces.
NIST physicists turn to radio dial for finer atomic matchmaking
Investigating mysterious data in ultracold gases of rubidium atoms, scientists at the Joint Quantum Institute of the National Institute of Standards and Technology (NIST) and the University of Maryland and their collaborators have found that properly tuned radio-frequency waves can influence how much the atoms attract or repel one another, opening up new ways to control their interactions.
More Magnetic Field Current Events and Magnetic Field News Articles
 |
Distortion by Magnetic Fields Distortion, Magnetic Fields’ second Nonesuch release, features the brilliant melodies and wry lyrics that composer and band leader Stephin Merritt has long been praised for, but, as the album title suggests, he serves them up with a twist. If the late, great Cole Porter had somehow been resurrected just in time to appear at the Coachella indie-rock fest, the results might sound something like this –"small, ironic tales of love and woe," as National Public Radio has described Merritt’s songs, startlingly enveloped in layers of live feedback that recall the noisy pop provocations of legendary Scottish quartet The Jesus and Mary Chain. As album producer, Merritt takes a completely novel approach to his deployment of feedback, going well beyond mere fuzzed-out guitar to... |
 |
69 Love Songs by Magnetic Fields 1999 and first new material in four years by Stephin Merrit 's main band (his side projects include Future Bible Heroes, Gothic Archies and The 6ths). Limited three disc set f eaturing more wonderful, yet cynically skewed, pop songs as only Merritt (and a midi) can do 'em! Features all three volumes of '69 Love Songs' (also sold separately), as well as a76 page booklet only available in this box! Each disc comes in a separate standard jewel case & together they come in a colorful CD-sized slipcase box. 69 tracks. |
 |
69 Love Songs by The Magnetic Fields Re-mastered limited edition (3,000) deluxe vinyl re-issue of their classic 1999 3-CD box set rumination on love. Funny, smart, dark, and memorable. Stephin Merritt solidifies his songwriting genius on his "most ambitious and fully realized work" - AMG. Beautifully packaged in a 10-inch slip case box with three double gatefold sleeves and the original booklet in 10-inch size. Includes coupon for MP3 download of entire album. |
 |
69 Love Songs Volume 1 The Magnetic Fields (Primary Contributor) |
 |
Get Lost by Magnetic Fields |
 |
i by Magnetic Fields The long-awaited follow-up to the acclaimed 1999 release 69 Love Songs, i finds singer/songwriter Stephin Merritt in full possession of his acerbic wit. Featuring lyrics ripe with melancholy and bittersweet imagery, the record's fourteen tracks are possibly the most personal Merritt has created to date -- a departure from the many voices on 69 Love Songs. |
 |
The Charm of the Highway Strip by Magnetic Fields Sweet and sour, incurably romantic, and deeply misanthropic, Magnetic Fields' mastermind Stephin Merritt is a one-of-a-kind voice in modern lo-fi pop. This 1994 outing is a bit of a departure, with Merritt taking his trademark ABBA-styled Casio-pop for a spin in the country--literally. Awash in lush, Nashville-ready production, songs like the doleful "Lonely Highway" (which encompasses snatches of the Lee Hazelwood classic "Jackson") and "Born on a Train" are nothing short of thrilling. But much of this particular stretch of the Fields is lacking in charm, since Merritt's wry stance chafes a bit too hard against the guileless melodies. Completists may feel compelled to take a ride, but novices should probably stick to the more urbane journeys offered by Holiday and Distant Plastic Trees.... |
 |
Magnetic Field(s) by Ron Loewinsohn (Author) Organised around the idea that "you can't know what a magnetic field is like unless you're inside of it," Ron Loewinsohn's first novel opens from the disturbing perspective of a burglar in the midst of a robbery, and travels through the thoughts and experiences (both real and imaginary) of a group of characters whose lives are connected both coincidentally and intimately. All of the characters have a common desire to imagine and invent rather horrifying stories about the lives of people around them. As the novel develops, certain phrasings and images recur improbably, drawing the reader into a subtle linguistic game that calls into question the nature of authorship, the ways we inhabit and invade each other's lives, and the shape of fiction itself. |
 |
The Wayward Bus/Distant Plastic Trees by Magnetic Fields |
 |
Distortion The Magnetic Fields (Primary Contributor) |
| © 2009 BrightSurf.com |