Showing posts with label discovers. Show all posts
Showing posts with label discovers. Show all posts

Friday, 11 November 2011

Kepler spacecraft discovers new multi-planet solar system

ScienceDaily (Oct. 5, 2011) — A team of researchers led by Bill Cochran of The University of Texas at Austin has used NASA's Kepler spacecraft to discover an unusual multiple-planet system containing a super-Earth and two Neptune-sized planets orbiting in resonance with each other.

They are announcing the find in Nantes, France at a joint meeting of the European Planetary Science Conference and the American Astronomical Society's Division of Planetary Science. The research will be published in a special Kepler issue of The Astrophysical Journal Supplement Series in November.

Cochran's team is announcing three planets orbiting Kepler-18, a star similar to the Sun. Kepler 18 is just 10 percent larger than the Sun and contains 97 percent of the Sun's mass. It may host more planets than the three just announced.

The planets are designated b, c, and d. All three planets orbit much closer to Kepler-18 than Mercury does to the Sun. Orbiting closest to Kepler-18 with a 3.5-day period, planet b weighs in at about 6.9 times the mass of Earth, and twice Earth's size. Planet b is considered a "super-Earth." Planet c has a mass of about 17 Earths, is about 5.5 times Earth's size, and orbits Kepler-18 in 7.6 days. Planet d weighs in at 16 Earths, at 7 times Earth's size, and has a 14.9-day orbit. The masses and sizes of c and d qualify them as low-density 2Neptune-class" planets.

Planet c orbits the star twice for every one orbit d makes. But the times that each of these planets transit the face of Kepler-18 "are not staying exactly on that orbital period," Cochran says. "One is slightly early when the other one is slightly late, [then] both are on time at the same time, and then vice-versa."

Scientifically speaking, c and d are orbiting in a 2:1 resonance. "It means they're interacting with each other," Cochran explains. "When they are close to each other ... they exchange energy, pull and tug on each other."

Kepler uses the "transit method" to look for planets. It monitors a star's brightness over time, looking for periodic dips that could indicate a planet passing in front of the star. A large part of the Kepler science team's work is proving that potential planets they find aren't something else that mimics the transit signature (such as a perfectly aligned background star, specifically either an eclipsing binary star or a single star orbited by a giant planet).

That follow-up work to Kepler is done by scores of scientists using ground-based telescopes the world over (including several at The University of Texas at Austin's McDonald Observatory) as well as Spitzer Space Telescope.

Kepler-18's planets c and d did astronomers a favour by proving their planet credentials up front via their orbital resonance; they had to be in the same planetary system as each other for the resonance to occur.

Confirming the planetary bona fides of planet b, the super-Earth, was much more complicated, Cochran says. His team used a technique called "validation," instead of verification. They set out to figure out the probability that it could be something other than a planet.

First, they used the Palomar 5-meter (200-inch) Hale Telescope with adaptive optics to take an extremely high-resolution look at the space around Kepler-18. They wanted to see if anything close to the star could be positively identified as a background object that would cause the transit signal they had attributed to a super-Earth.

"We successively went through every possible type of object that could be there," Cochran says. "There are limits on the sort of objects that can be there at different distances from the star." Astronomers know how many of different types of objects (various kinds of stars, background galaxies, and more) are seen on average in the sky. They didn't find anything in the Palomar image.

"There's a small possibility that [planet b] is due to a background object, but we're very confident that it's probably a planet," Cochran says. His team calculated that the likelihood the object is a planet is 700 times more likely than the likelihood that it's a background object.

The process is called "planet validation," rather than the usual "planet verification." Cochran says it's important to understand the difference -- not just for this system, but for future discoveries from Kepler and other missions.

"We're trying to prepare the astronomical community and the public for the concept of validation," he says. "The goal of Kepler is to find an Earth-sized planet in the habitable zone [where life could arise], with a one-year orbit. Proving that such an object really is a planet is very difficult [with current technology]. When we find what looks to be a habitable Earth, we'll have to use a validation process, rather than a confirmation process. We're going to have to make statistical arguments."

Kepler was selected as the tenth NASA Discovery mission. NASA Ames Research Center, Moffett Field, Calif., is the home organization of the science principal investigator, and is responsible for the ground system development, mission operations and science data analysis. Jet Propulsion Laboratory, Pasadena, Calif., managed the Kepler mission development. Ball Aerospace & Technologies Corp. of Boulder, Colo., developed the Kepler flight system and supports mission operations with the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder. The Space Telescope Science Institute in Baltimore archives, hosts, and distributes the Kepler science data. For more information about the Kepler mission, visit: http://www.nasa.gov/kepler.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by McDonald Observatory, University of Texas at Austin.

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.


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Tuesday, 8 November 2011

Kepler spacecraft discovers new multi-planet solar system

ScienceDaily (Oct. 5, 2011) — A team of researchers led by Bill Cochran of The University of Texas at Austin has used NASA's Kepler spacecraft to discover an unusual multiple-planet system containing a super-Earth and two Neptune-sized planets orbiting in resonance with each other.

They are announcing the find in Nantes, France at a joint meeting of the European Planetary Science Conference and the American Astronomical Society's Division of Planetary Science. The research will be published in a special Kepler issue of The Astrophysical Journal Supplement Series in November.

Cochran's team is announcing three planets orbiting Kepler-18, a star similar to the Sun. Kepler 18 is just 10 percent larger than the Sun and contains 97 percent of the Sun's mass. It may host more planets than the three just announced.

The planets are designated b, c, and d. All three planets orbit much closer to Kepler-18 than Mercury does to the Sun. Orbiting closest to Kepler-18 with a 3.5-day period, planet b weighs in at about 6.9 times the mass of Earth, and twice Earth's size. Planet b is considered a "super-Earth." Planet c has a mass of about 17 Earths, is about 5.5 times Earth's size, and orbits Kepler-18 in 7.6 days. Planet d weighs in at 16 Earths, at 7 times Earth's size, and has a 14.9-day orbit. The masses and sizes of c and d qualify them as low-density 2Neptune-class" planets.

Planet c orbits the star twice for every one orbit d makes. But the times that each of these planets transit the face of Kepler-18 "are not staying exactly on that orbital period," Cochran says. "One is slightly early when the other one is slightly late, [then] both are on time at the same time, and then vice-versa."

Scientifically speaking, c and d are orbiting in a 2:1 resonance. "It means they're interacting with each other," Cochran explains. "When they are close to each other ... they exchange energy, pull and tug on each other."

Kepler uses the "transit method" to look for planets. It monitors a star's brightness over time, looking for periodic dips that could indicate a planet passing in front of the star. A large part of the Kepler science team's work is proving that potential planets they find aren't something else that mimics the transit signature (such as a perfectly aligned background star, specifically either an eclipsing binary star or a single star orbited by a giant planet).

That follow-up work to Kepler is done by scores of scientists using ground-based telescopes the world over (including several at The University of Texas at Austin's McDonald Observatory) as well as Spitzer Space Telescope.

Kepler-18's planets c and d did astronomers a favour by proving their planet credentials up front via their orbital resonance; they had to be in the same planetary system as each other for the resonance to occur.

Confirming the planetary bona fides of planet b, the super-Earth, was much more complicated, Cochran says. His team used a technique called "validation," instead of verification. They set out to figure out the probability that it could be something other than a planet.

First, they used the Palomar 5-meter (200-inch) Hale Telescope with adaptive optics to take an extremely high-resolution look at the space around Kepler-18. They wanted to see if anything close to the star could be positively identified as a background object that would cause the transit signal they had attributed to a super-Earth.

"We successively went through every possible type of object that could be there," Cochran says. "There are limits on the sort of objects that can be there at different distances from the star." Astronomers know how many of different types of objects (various kinds of stars, background galaxies, and more) are seen on average in the sky. They didn't find anything in the Palomar image.

"There's a small possibility that [planet b] is due to a background object, but we're very confident that it's probably a planet," Cochran says. His team calculated that the likelihood the object is a planet is 700 times more likely than the likelihood that it's a background object.

The process is called "planet validation," rather than the usual "planet verification." Cochran says it's important to understand the difference -- not just for this system, but for future discoveries from Kepler and other missions.

"We're trying to prepare the astronomical community and the public for the concept of validation," he says. "The goal of Kepler is to find an Earth-sized planet in the habitable zone [where life could arise], with a one-year orbit. Proving that such an object really is a planet is very difficult [with current technology]. When we find what looks to be a habitable Earth, we'll have to use a validation process, rather than a confirmation process. We're going to have to make statistical arguments."

Kepler was selected as the tenth NASA Discovery mission. NASA Ames Research Center, Moffett Field, Calif., is the home organization of the science principal investigator, and is responsible for the ground system development, mission operations and science data analysis. Jet Propulsion Laboratory, Pasadena, Calif., managed the Kepler mission development. Ball Aerospace & Technologies Corp. of Boulder, Colo., developed the Kepler flight system and supports mission operations with the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder. The Space Telescope Science Institute in Baltimore archives, hosts, and distributes the Kepler science data. For more information about the Kepler mission, visit: http://www.nasa.gov/kepler.

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The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by McDonald Observatory, University of Texas at Austin.

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.


View the original article here

Monday, 31 October 2011

Venus has an ozone layer too, space probe discovers

ScienceDaily (Oct. 9, 2011) — The European Space Agency's Venus Express spacecraft has discovered an ozone layer high in the atmosphere of Venus. Comparing its properties with those of the equivalent layers on Earth and Mars will help astronomers refine their searches for life on other planets.

The results are being presented at the Joint Meeting of the European Planetary Science Congress and the American Astronomical Society's Division for Planetary Sciences.

Venus Express made the discovery while watching stars seen right at the edge of the planet set through its atmosphere. Its SPICAV instrument analysed the starlight, looking for the characteristic fingerprints of gases in the atmosphere as they absorbed light at specific wavelengths.

The ozone was detectable because it absorbed some of the ultraviolet from the starlight. Ozone is a molecule containing three oxygen atoms. According to computer models, the ozone on Venus is formed when sunlight breaks up carbon dioxide molecules, releasing oxygen atoms.

These atoms are then swept around to the nightside of the planet by winds in the atmosphere: they can then combine to form two-atom oxygen molecules, but also sometimes three-atom ozone molecules.

"This detection gives us an important constraint on understanding the chemistry of Venus' atmosphere," says Franck Montmessin, who led the research.

It may also offer a useful comparison for searching for life on other worlds. Ozone has only previously been detected in the atmospheres of Earth and Mars. On Earth, it is of fundamental importance to life because it absorbs much of the Sun's harmful ultraviolet rays. Not only that, it is thought to have been generated by life itself in the first place.

The build-up of oxygen, and consequently ozone, in Earth's atmosphere began 2.4 billion years ago. Although the exact reasons for it are not entirely understood, microbes excreting oxygen as a waste gas must have played an important role.

Along with plant life, they continue to do so, constantly replenishing Earth's oxygen and ozone. As a result, some astrobiologists have suggested that the simultaneous presence of carbon dioxide, oxygen and ozone in an atmosphere could be used to tell whether there could be life on the planet.

This would allow future telescopes to target planets around other stars and assess their habitability. However, as these new results highlight, the amount of ozone is crucial.

The small amount of ozone in Mars' atmosphere has not been generated by life. There, it is the result of sunlight breaking up carbon dioxide molecules. Venus too, now supports this view of a modest ozone build-up by non-biological means. Its ozone layer sits at an altitude of 100 km, about four times higher in the atmosphere than Earth's and is a hundred to a thousand times less dense.

Theoretical work by astrobiologists suggests that a planet's ozone concentration must be 20%of Earth's value before life should be considered as a cause. These new results support that conclusion because Venus clearly remains below this threshold.

"We can use these new observations to test and refine the scenarios for the detection of life on other worlds," says Dr Montmessin.

Yet, even if there is no life on Venus, the detection of ozone there brings Venus a step closer to Earth and Mars. All three planets have an ozone layer.

"This ozone detection tells us a lot about the circulation and the chemistry of Venus' atmosphere" says Håkan Svedhem, ESA Project Scientist for the Venus Express mission. "Beyond that, it is yet more evidence of the fundamental similarity between the rocky planets, and shows the importance of studying Venus to understand them all."

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Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Europlanet Media Centre, via AlphaGalileo.

Journal Reference:

F. Montmessin, J.-L. Bertaux, F. Lefèvre, E. Marcq, D. Belyaev, J.-C. Gérard, O. Korablev, A. Fedorova, V. Sarago, A.C. Vandaele. A layer of ozone detected in the nightside upper atmosphere of Venus. Icarus, 2011; 216 (1): 82 DOI: 10.1016/j.icarus.2011.08.010

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.


View the original article here

Sunday, 30 October 2011

Venus has an ozone layer too, space probe discovers

ScienceDaily (Oct. 9, 2011) — The European Space Agency's Venus Express spacecraft has discovered an ozone layer high in the atmosphere of Venus. Comparing its properties with those of the equivalent layers on Earth and Mars will help astronomers refine their searches for life on other planets.

The results are being presented at the Joint Meeting of the European Planetary Science Congress and the American Astronomical Society's Division for Planetary Sciences.

Venus Express made the discovery while watching stars seen right at the edge of the planet set through its atmosphere. Its SPICAV instrument analysed the starlight, looking for the characteristic fingerprints of gases in the atmosphere as they absorbed light at specific wavelengths.

The ozone was detectable because it absorbed some of the ultraviolet from the starlight. Ozone is a molecule containing three oxygen atoms. According to computer models, the ozone on Venus is formed when sunlight breaks up carbon dioxide molecules, releasing oxygen atoms.

These atoms are then swept around to the nightside of the planet by winds in the atmosphere: they can then combine to form two-atom oxygen molecules, but also sometimes three-atom ozone molecules.

"This detection gives us an important constraint on understanding the chemistry of Venus' atmosphere," says Franck Montmessin, who led the research.

It may also offer a useful comparison for searching for life on other worlds. Ozone has only previously been detected in the atmospheres of Earth and Mars. On Earth, it is of fundamental importance to life because it absorbs much of the Sun's harmful ultraviolet rays. Not only that, it is thought to have been generated by life itself in the first place.

The build-up of oxygen, and consequently ozone, in Earth's atmosphere began 2.4 billion years ago. Although the exact reasons for it are not entirely understood, microbes excreting oxygen as a waste gas must have played an important role.

Along with plant life, they continue to do so, constantly replenishing Earth's oxygen and ozone. As a result, some astrobiologists have suggested that the simultaneous presence of carbon dioxide, oxygen and ozone in an atmosphere could be used to tell whether there could be life on the planet.

This would allow future telescopes to target planets around other stars and assess their habitability. However, as these new results highlight, the amount of ozone is crucial.

The small amount of ozone in Mars' atmosphere has not been generated by life. There, it is the result of sunlight breaking up carbon dioxide molecules. Venus too, now supports this view of a modest ozone build-up by non-biological means. Its ozone layer sits at an altitude of 100 km, about four times higher in the atmosphere than Earth's and is a hundred to a thousand times less dense.

Theoretical work by astrobiologists suggests that a planet's ozone concentration must be 20%of Earth's value before life should be considered as a cause. These new results support that conclusion because Venus clearly remains below this threshold.

"We can use these new observations to test and refine the scenarios for the detection of life on other worlds," says Dr Montmessin.

Yet, even if there is no life on Venus, the detection of ozone there brings Venus a step closer to Earth and Mars. All three planets have an ozone layer.

"This ozone detection tells us a lot about the circulation and the chemistry of Venus' atmosphere" says Håkan Svedhem, ESA Project Scientist for the Venus Express mission. "Beyond that, it is yet more evidence of the fundamental similarity between the rocky planets, and shows the importance of studying Venus to understand them all."

Recommend this story on Facebook, Twitter,
and Google +1:

Other bookmarking and sharing tools:

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Europlanet Media Centre, via AlphaGalileo.

Journal Reference:

F. Montmessin, J.-L. Bertaux, F. Lefèvre, E. Marcq, D. Belyaev, J.-C. Gérard, O. Korablev, A. Fedorova, V. Sarago, A.C. Vandaele. A layer of ozone detected in the nightside upper atmosphere of Venus. Icarus, 2011; 216 (1): 82 DOI: 10.1016/j.icarus.2011.08.010

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.


View the original article here

Tuesday, 5 July 2011

An Alice-in-Wonderland universe? Physicist discovers an apparent cosmic parity violation

ScienceDaily (June 10, 2011) — Does our universe have mirror symmetry? That is the question Prof. Michael Longo of the University of Michigan's Physics Department asked. The answer could perhaps be found by studying the rotation directions of spiral galaxies.

Physicists and astronomers have always assumed that the Universe has this symmetry. To test this, Longo and his team of five undergraduates used data from the Sloan Digital Sky Survey to study the rotation directions of spiral galaxies. The mirror image of a counter-clockwise rotating galaxy, like the example, would have clockwise rotation. An excess of one type over the other would be evidence for a breakdown of mirror symmetry, or, in physics speak, a "parity violation" on cosmic scales.

Longo and his team, after studying tens of thousands of spiral galaxies, found an excess of left-handed spirals in the part of the sky toward the north pole of our galaxy, the Milky Way. The excess is small, about 7%. However, Longo estimates the chance that the excess could be a cosmic accident is something like one in a million. The effect extended out to distances over 600 million light years. Our galaxy also rotates in the same sense.

"If verified, this data would be extremely important because it is almost universally accepted that on sufficiently large scales the universe is isotropic (no special direction)," he said.

If spiral galaxies tend to have their rotation axes aligned in one direction, it means that there is also a preferred direction in the universe. This violates another tenet of astrophysics that assumes the universe has no special direction or is "isotropic."

Because the Sloan telescope is in the northern hemisphere, the data that was analyzed came mostly from the northern hemisphere of the sky. An important test of this result will be to see if there is an excess of right-handed spiral galaxies in the southern hemisphere. Longo looked at the limited sample that is available now, and found that there does seem to be more right-handed ones there. More data from the southern hemisphere will provide an important test of this result.

Longo's paper has recently been published in Physics Letters B. An anonymous referee who reviewed the paper for the journal said: "In the paper the author claims that there is a preferred handedness of spiral galaxies indicating a preferred direction in the universe. Such [a] claim, if proven true, would have a profound impact on cosmology and would very likely result in a Nobel prize."

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Michigan, Physics Department.

Journal Reference:

Michael J. Longo. Detection of a dipole in the handedness of spiral galaxies with redshifts z~0.04. Physics Letters B, 2011; 699 (4): 224 DOI: 10.1016/j.physletb.2011.04.008

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.


View the original article here

Monday, 4 July 2011

Using magnets to help prevent heart attacks: Magnetic field can reduce blood viscosity, physicist discovers

ScienceDaily (June 8, 2011) — If a person's blood becomes too thick it can damage blood vessels and increase the risk of heart attacks. But a Temple University physicist has discovered that he can thin the human blood by subjecting it to a magnetic field.

Rongjia Tao, professor and chair of physics at Temple University, has pioneered the use of electric or magnetic fields to decrease the viscosity of oil in engines and pipelines. Now, he is using the same magnetic fields to thin human blood in the circulation system.

Because red blood cells contain iron, Tao has been able to reduce a person's blood viscosity by 20-30 percent by subjecting it to a magnetic field of 1.3 Telsa (about the same as an MRI) for about one minute.

Tao and his collaborator tested numerous blood samples in a Temple lab and found that the magnetic field polarizes the red blood cells causing them to link together in short chains, streamlining the movement of the blood. Because these chains are larger than the single blood cells, they flow down the center, reducing the friction against the walls of the blood vessels. The combined effects reduce the viscosity of the blood, helping it to flow more freely.

When the magnetic field was taken away, the blood's original viscosity state slowly returned, but over a period of several hours.

"By selecting a suitable magnetic field strength and pulse duration, we will be able to control the size of the aggregated red-cell chains, hence to control the blood's viscosity," said Tao. "This method of magneto-rheology provides an effective way to control the blood viscosity within a selected range."

Currently, the only method for thinning blood is through drugs such as aspirin; however, these drugs often produce unwanted side effects. Tao said that the magnetic field method is not only safer, it is repeatable. The magnetic fields may be reapplied and the viscosity reduced again. He also added that the viscosity reduction does not affect the red blood cells' normal function.

Tao said that further studies are needed and that he hopes to ultimately develop this technology into an acceptable therapy to prevent heart disease.

Tao and his former graduate student, Ke "Colin" Huang, now a medical physics resident in the Department of Radiation Oncology at the University of Michigan, are publishing their findings in the journal Physical Review E.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Temple University, via EurekAlert!, a service of AAAS.

Note: If no author is given, the source is cited instead.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.


View the original article here

Friday, 1 July 2011

An Alice-in-Wonderland universe? Physicist discovers an apparent cosmic parity violation

ScienceDaily (June 10, 2011) — Does our universe have mirror symmetry? That is the question Prof. Michael Longo of the University of Michigan's Physics Department asked. The answer could perhaps be found by studying the rotation directions of spiral galaxies.

Physicists and astronomers have always assumed that the Universe has this symmetry. To test this, Longo and his team of five undergraduates used data from the Sloan Digital Sky Survey to study the rotation directions of spiral galaxies. The mirror image of a counter-clockwise rotating galaxy, like the example, would have clockwise rotation. An excess of one type over the other would be evidence for a breakdown of mirror symmetry, or, in physics speak, a "parity violation" on cosmic scales.

Longo and his team, after studying tens of thousands of spiral galaxies, found an excess of left-handed spirals in the part of the sky toward the north pole of our galaxy, the Milky Way. The excess is small, about 7%. However, Longo estimates the chance that the excess could be a cosmic accident is something like one in a million. The effect extended out to distances over 600 million light years. Our galaxy also rotates in the same sense.

"If verified, this data would be extremely important because it is almost universally accepted that on sufficiently large scales the universe is isotropic (no special direction)," he said.

If spiral galaxies tend to have their rotation axes aligned in one direction, it means that there is also a preferred direction in the universe. This violates another tenet of astrophysics that assumes the universe has no special direction or is "isotropic."

Because the Sloan telescope is in the northern hemisphere, the data that was analyzed came mostly from the northern hemisphere of the sky. An important test of this result will be to see if there is an excess of right-handed spiral galaxies in the southern hemisphere. Longo looked at the limited sample that is available now, and found that there does seem to be more right-handed ones there. More data from the southern hemisphere will provide an important test of this result.

Longo's paper has recently been published in Physics Letters B. An anonymous referee who reviewed the paper for the journal said: "In the paper the author claims that there is a preferred handedness of spiral galaxies indicating a preferred direction in the universe. Such [a] claim, if proven true, would have a profound impact on cosmology and would very likely result in a Nobel prize."

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of Michigan, Physics Department.

Journal Reference:

Michael J. Longo. Detection of a dipole in the handedness of spiral galaxies with redshifts z~0.04. Physics Letters B, 2011; 699 (4): 224 DOI: 10.1016/j.physletb.2011.04.008

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.


View the original article here

Tuesday, 28 June 2011

Using magnets to help prevent heart attacks: Magnetic field can reduce blood viscosity, physicist discovers

ScienceDaily (June 8, 2011) — If a person's blood becomes too thick it can damage blood vessels and increase the risk of heart attacks. But a Temple University physicist has discovered that he can thin the human blood by subjecting it to a magnetic field.

Rongjia Tao, professor and chair of physics at Temple University, has pioneered the use of electric or magnetic fields to decrease the viscosity of oil in engines and pipelines. Now, he is using the same magnetic fields to thin human blood in the circulation system.

Because red blood cells contain iron, Tao has been able to reduce a person's blood viscosity by 20-30 percent by subjecting it to a magnetic field of 1.3 Telsa (about the same as an MRI) for about one minute.

Tao and his collaborator tested numerous blood samples in a Temple lab and found that the magnetic field polarizes the red blood cells causing them to link together in short chains, streamlining the movement of the blood. Because these chains are larger than the single blood cells, they flow down the center, reducing the friction against the walls of the blood vessels. The combined effects reduce the viscosity of the blood, helping it to flow more freely.

When the magnetic field was taken away, the blood's original viscosity state slowly returned, but over a period of several hours.

"By selecting a suitable magnetic field strength and pulse duration, we will be able to control the size of the aggregated red-cell chains, hence to control the blood's viscosity," said Tao. "This method of magneto-rheology provides an effective way to control the blood viscosity within a selected range."

Currently, the only method for thinning blood is through drugs such as aspirin; however, these drugs often produce unwanted side effects. Tao said that the magnetic field method is not only safer, it is repeatable. The magnetic fields may be reapplied and the viscosity reduced again. He also added that the viscosity reduction does not affect the red blood cells' normal function.

Tao said that further studies are needed and that he hopes to ultimately develop this technology into an acceptable therapy to prevent heart disease.

Tao and his former graduate student, Ke "Colin" Huang, now a medical physics resident in the Department of Radiation Oncology at the University of Michigan, are publishing their findings in the journal Physical Review E.

Story Source:

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Temple University, via EurekAlert!, a service of AAAS.

Note: If no author is given, the source is cited instead.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.


View the original article here