Exlusive interview with Bruce Tsurutani, space weather specialist at NASA's JPL, on the Solar minimum
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“Every little piece of new knowledge is used by space agencies around the world to design new instrumentation to probe the unknown and unexplained. For example, who would have thought that the location of where coronal holes are on the Sun would be important for space weather effects?”
Asking questions in order to find answers and, of course, create a new path for new questions: This is the job of Bruce Tsurutani, a space weather scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
Tsurutani is in charge for the JPL to monitor solar activity and reveal the effects of wind and sun flares on Earth. Professor Tsurutani, awarded in 2009 the John A. Fleming Medal, and has spent much of his 40-year career on understanding the Sun-Earth connection and interplanetary physics.
He is the lead author of the paper “The solar and interplanetary causes of the recent minimum in geomagnetic activity,” co-authored by professors Walter Gonzalez and Ezequiel Echer.
In an exclusive interview interview, Professor Tsurutani describes what the solar minimum means for the planet and the solar system, how a magnetic storm can destroy or damage the human devices, and what are the studies run by NASA and U.S. governmental agencies in order to predict possible scenarios and the subsequent remedies.
Doctor Tsurutani, as the lead author of the paper “The solar and interplanetary causes of the recent minimum in geomagnetic activity,” can you explain what is the main or key result of your research?
The efforts of my two Brazilian colleagues, Profs. Echer and Gonzalez, and myself is to understand all facets of how the sun affects us here on Earth. We have previously studied two other phases of the 11 year solar (sunspot) cycle: solar maximum and the declining phase. Now we have starting to study the solar minimum phase.
Our main result was to explain how this record low geomagnetic activity at Earth occurred. We found that the coronal holes were small and placed at midlatitude locations on the sun and there were extremely low solar magnetic fields. The former is a poor location for solar wind impingement on the Earth (which is in the ecliptic plane) to occur. All of this was made possible by a very nice paper on coronal hole evolution written by G. de Toma. This stimulated our thinking.
What is the correlation between the solar wind and the 'solar minimum'?
During solar minimum (late 2008) the average solar wind speed detected at Earth was still high. Six months to a year later, the average speeds were much lower. So there was a delay of the solar wind speed decrease from solar minimum. However the speed of the solar wind coming from coronal holes on the sun did not change. It was just the location of the coronal holes that did. Does this happen every solar cycle? Probably so. But more research is needed to determine whether this hypothesis is correct or not. What in the interior of the Sun makes these coronal holes appear at middle latitudes? At this time we do not know.
What is the 'solar minimum' impact on our daily life and the impact on our space devices, like satellites?
Actually we now know that during solar minimum the environment is quite benign. There are no (or at least very few) solar flares or enhancements of the Van Allen radiation belts that could impact satellites. This would be a good time for space travel! There should not be any impacts to our daily lives (except beautiful auroras will be hard to find!).
How can solar wind affect the solar system mechanics?
The pressure from the solar wind is quite weak and has little effect on the solar system as it is today. However the distant past may be a different story.
The magnetic interactions are vital in our understanding of the universe; how does your research as a space weather specialist help to improve that knowledge?
Yes, space weather scientists now know that magnetic interactions is the most important mechanism for solar flares on the sun as well as energy transfer from the solar wind to the Earth’s magnetosphere. In 1859, R. Carrington made the first well-documented observation of a solar flare. He also made reference to a magnetic storm at Earth. From this, Profs. G. Lakhina and S. Alex of the Indian Institute of Geomagnetism, Prof. Gonzalez and I studied the solar and interplanetary causes of this storm — by far the largest ever recorded at Earth. We have never seen anything close to this intensity in our lifetimes. We did this as part of our solar maximum phase study. Magnetic interactions were presumed to take place both at the sun and at Earth.
Luckily, because this was such a huge event, scientists at the time took note and wrote papers on the fires set, electrical shocks that happened, and the brilliant auroral displays that occurred at Earth. This old information were used in our study. In 1859 the world was in a state of low technology in comparison to today. The “high tech” device at the time was the telegraph. NASA together with other U.S. governmental agencies are presently studying what would happen if a magnetic storm of Carrington intensity happened again today? Would power grids go out? Could satellites come down? Would the radiation from the solar flare and the Van Allen belts damage spaceborne electronics? The U.S. plans to be prepared in case something of this magnitude happens again.
Magnetic interactions are also important for laboratory plasma physics and astrophysics as well. Space weather scientists meet with plasma fusion physicists and astrophysicists on a regular basis to compare ideas and observations.
Have results of recent scientific investigations led to improvements that can be used in the near future on solar facilities?
Definitely. Every little piece of new knowledge is used by space agencies around the world to design new instrumentation to probe the unknown/unexplained. For example, who would have thought that the location of where coronal holes are on the Sun would be important for space weather effects? Now that it is known that this is important for geomagnetic activity at Earth, scientists will attempt to explain this.
What would happen if coronal holes disappeared altogether? Or the solar magnetic field became even weaker? Do we know enough about the interior of the Sun to be able to predict when this could happen, and for how long? This is the goal for all of us working in the field.
Asking questions in order to find answers and, of course, create a new path for new questions: This is the job of Bruce Tsurutani, a space weather scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
Tsurutani is in charge for the JPL to monitor solar activity and reveal the effects of wind and sun flares on Earth. Professor Tsurutani, awarded in 2009 the John A. Fleming Medal, and has spent much of his 40-year career on understanding the Sun-Earth connection and interplanetary physics.
He is the lead author of the paper “The solar and interplanetary causes of the recent minimum in geomagnetic activity,” co-authored by professors Walter Gonzalez and Ezequiel Echer.
In an exclusive interview interview, Professor Tsurutani describes what the solar minimum means for the planet and the solar system, how a magnetic storm can destroy or damage the human devices, and what are the studies run by NASA and U.S. governmental agencies in order to predict possible scenarios and the subsequent remedies.
Doctor Tsurutani, as the lead author of the paper “The solar and interplanetary causes of the recent minimum in geomagnetic activity,” can you explain what is the main or key result of your research?
The efforts of my two Brazilian colleagues, Profs. Echer and Gonzalez, and myself is to understand all facets of how the sun affects us here on Earth. We have previously studied two other phases of the 11 year solar (sunspot) cycle: solar maximum and the declining phase. Now we have starting to study the solar minimum phase.
Our main result was to explain how this record low geomagnetic activity at Earth occurred. We found that the coronal holes were small and placed at midlatitude locations on the sun and there were extremely low solar magnetic fields. The former is a poor location for solar wind impingement on the Earth (which is in the ecliptic plane) to occur. All of this was made possible by a very nice paper on coronal hole evolution written by G. de Toma. This stimulated our thinking.
What is the correlation between the solar wind and the 'solar minimum'?
During solar minimum (late 2008) the average solar wind speed detected at Earth was still high. Six months to a year later, the average speeds were much lower. So there was a delay of the solar wind speed decrease from solar minimum. However the speed of the solar wind coming from coronal holes on the sun did not change. It was just the location of the coronal holes that did. Does this happen every solar cycle? Probably so. But more research is needed to determine whether this hypothesis is correct or not. What in the interior of the Sun makes these coronal holes appear at middle latitudes? At this time we do not know.
What is the 'solar minimum' impact on our daily life and the impact on our space devices, like satellites?
Actually we now know that during solar minimum the environment is quite benign. There are no (or at least very few) solar flares or enhancements of the Van Allen radiation belts that could impact satellites. This would be a good time for space travel! There should not be any impacts to our daily lives (except beautiful auroras will be hard to find!).
How can solar wind affect the solar system mechanics?
The pressure from the solar wind is quite weak and has little effect on the solar system as it is today. However the distant past may be a different story.
The magnetic interactions are vital in our understanding of the universe; how does your research as a space weather specialist help to improve that knowledge?
Yes, space weather scientists now know that magnetic interactions is the most important mechanism for solar flares on the sun as well as energy transfer from the solar wind to the Earth’s magnetosphere. In 1859, R. Carrington made the first well-documented observation of a solar flare. He also made reference to a magnetic storm at Earth. From this, Profs. G. Lakhina and S. Alex of the Indian Institute of Geomagnetism, Prof. Gonzalez and I studied the solar and interplanetary causes of this storm — by far the largest ever recorded at Earth. We have never seen anything close to this intensity in our lifetimes. We did this as part of our solar maximum phase study. Magnetic interactions were presumed to take place both at the sun and at Earth.
Luckily, because this was such a huge event, scientists at the time took note and wrote papers on the fires set, electrical shocks that happened, and the brilliant auroral displays that occurred at Earth. This old information were used in our study. In 1859 the world was in a state of low technology in comparison to today. The “high tech” device at the time was the telegraph. NASA together with other U.S. governmental agencies are presently studying what would happen if a magnetic storm of Carrington intensity happened again today? Would power grids go out? Could satellites come down? Would the radiation from the solar flare and the Van Allen belts damage spaceborne electronics? The U.S. plans to be prepared in case something of this magnitude happens again.
Magnetic interactions are also important for laboratory plasma physics and astrophysics as well. Space weather scientists meet with plasma fusion physicists and astrophysicists on a regular basis to compare ideas and observations.
Have results of recent scientific investigations led to improvements that can be used in the near future on solar facilities?
Definitely. Every little piece of new knowledge is used by space agencies around the world to design new instrumentation to probe the unknown/unexplained. For example, who would have thought that the location of where coronal holes are on the Sun would be important for space weather effects? Now that it is known that this is important for geomagnetic activity at Earth, scientists will attempt to explain this.
What would happen if coronal holes disappeared altogether? Or the solar magnetic field became even weaker? Do we know enough about the interior of the Sun to be able to predict when this could happen, and for how long? This is the goal for all of us working in the field.
