A team of astronomers in California have detected magnetic field of a galaxy in far universe. These astronomers are studying the early universe by a powerful radio telescope. This measurement of magnetic field is as it was 6.5 billion years ago.
Prior Believes
Astronomers believe that magnetic fields within our own Milky Way and other galaxies near milky way, control the rate of star formation and the dynamics of interstellar gas. This magnetic field arose from a slow Dynamo Effect. This magnetic field in these galaxies grew very gradually as they evolved over 5 billion to 10 billion years to their current levels.
But now astronomers have reported that the magnetic field that they have measured in a distant Protogalaxy is at least 10 times greater than average value of Milky Way. This report has been published in October issue of Nature.
According to Arthur Wolfe (Professor of Physics at UC San Diego's Center for Astrophysics and Space Sciences and head of the team), this research is a Complete Surprise. The magnetic field measured is at least an order of magnitude larger than the average value of the magnetic field detected in our own galaxy.
Powerful Radio Telescope and Useful Results
Astronomers used world's largest fully steerable radio telescope for their study known as Robert C. Byrd Green Bank Telescope located in Green Bank, West Virginia. This grand telescope is operated by National Radio Astronomy Observatory of National Science Foundation.
They studied DLA-3C286 protogalaxy located in a region of northern sky.
Magnetic Field outside our galaxy is very less know formerly. Prior to this study astronomers have measured magnetic field of only one nearby galaxy but that field was very weak.
A team of Swiss and American astronomers in July 17 issue of Nature magazine reported that they have found that magnetic field of about 20 distant galaxies were as when the universe was only a third of its current age as they are in the mature galaxies today. This study was done by using bright light from quasars.
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."
Challenge to Dynamo Model
These results have put a challenge before Dynamo Model.
According to Arthur Wolfe "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."
Other Plausible Explanations
According to Wolfe their team has two other plausible explanations for their observations.
1) It may be possible that they 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.
2) It is also possible that the field they have detected has been amplified by a shock wave generated by the collision between two galaxies.
But in either case it has been proved that magnetic fields may be important factors in the evolution of galaxies or we can also say that it is responsible for the low star formation rates detected throughout the gaseous progenitors of young galaxies in the early universe.
The Next Challenge
The next challenge in words of J. Xavier Prochaska, a team member and professor of astronomy at US Santa Cruz, is to observe galaxies throughout the universe.
Major Contributions in Research
Other team members included Regina Jorgenson (UCSD graduate student in physics); Carl Heiles (professor of astronomy at UC Berkeley); Timothy Robishaw (graduate student at Berkeley). This research was funded by National Science Foundation.
Prior Believes
Astronomers believe that magnetic fields within our own Milky Way and other galaxies near milky way, control the rate of star formation and the dynamics of interstellar gas. This magnetic field arose from a slow Dynamo Effect. This magnetic field in these galaxies grew very gradually as they evolved over 5 billion to 10 billion years to their current levels.
But now astronomers have reported that the magnetic field that they have measured in a distant Protogalaxy is at least 10 times greater than average value of Milky Way. This report has been published in October issue of Nature.
According to Arthur Wolfe (Professor of Physics at UC San Diego's Center for Astrophysics and Space Sciences and head of the team), this research is a Complete Surprise. The magnetic field measured is at least an order of magnitude larger than the average value of the magnetic field detected in our own galaxy.
Powerful Radio Telescope and Useful Results
Astronomers used world's largest fully steerable radio telescope for their study known as Robert C. Byrd Green Bank Telescope located in Green Bank, West Virginia. This grand telescope is operated by National Radio Astronomy Observatory of National Science Foundation.
They studied DLA-3C286 protogalaxy located in a region of northern sky.
Magnetic Field outside our galaxy is very less know formerly. Prior to this study astronomers have measured magnetic field of only one nearby galaxy but that field was very weak.
A team of Swiss and American astronomers in July 17 issue of Nature magazine reported that they have found that magnetic field of about 20 distant galaxies were as when the universe was only a third of its current age as they are in the mature galaxies today. This study was done by using bright light from quasars.
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."
Challenge to Dynamo Model
These results have put a challenge before Dynamo Model.
According to Arthur Wolfe "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."
Other Plausible Explanations
According to Wolfe their team has two other plausible explanations for their observations.
1) It may be possible that they 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.
2) It is also possible that the field they have detected has been amplified by a shock wave generated by the collision between two galaxies.
But in either case it has been proved that magnetic fields may be important factors in the evolution of galaxies or we can also say that it is responsible for the low star formation rates detected throughout the gaseous progenitors of young galaxies in the early universe.
The Next Challenge
The next challenge in words of J. Xavier Prochaska, a team member and professor of astronomy at US Santa Cruz, is to observe galaxies throughout the universe.
Major Contributions in Research
Other team members included Regina Jorgenson (UCSD graduate student in physics); Carl Heiles (professor of astronomy at UC Berkeley); Timothy Robishaw (graduate student at Berkeley). This research was funded by National Science Foundation.
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