The news from the annual meeting of the Solar Physics Division of the American Astronomical Society is not rent-seeking behavior from hack scientists with a political agenda. These three studies largely confirm theories about the variability in the Sun's activity, fueled by the cyclical reversal of the Sun's (and, thus, the "Interplanetary") magnetic field.
The outcome of these predictions, should they pan out, is grim for Deep Space travel. A little problem nagging those who want to brave the trip to Mars and back, skipping ahead of the class by ignoring what the Moon has been waiting to teach us since the United States Congress made the decision to drop out in 1971, may be coming into focus a lot more rapidly than any of us hoped.
These reputable long-term studies back-up predictions - dismissed at the time - that the Sun was literally winding up, and was overdue, for one of those poorly understood but historically recorded periods of relative quiet.
Whether this means a Maunder Minimum, with effects on Earth like a "little Ice Age," as took place in the late 17th and early 18th centuries, is not the immediate story, yet. I think the big story will be a change in our thinking about the Sun's cyclical behavior, its long-period cyclical behavior.
Most of us, at one point or another, have seen the charts showing the 22-years solar cycle plotted out for at least the last century or less. Sunspots are a secondary effect of what's really being measured. They are a visible manifestation of solar maximum, not the thing itself. An outwardly bright showing of the tightly wound magnetic field of the Sun generated deep within its interior.
The Sun is not a solid, and parts of this "mass of incandescent gas" are rotating around its axis a differing speeds, generating magnetic fields that break apart and sometime oppose one another with violence we poorly imagine.
But, as a recordable phenomena in the historic records here in the West since A.D. 1645 we have been able to use sunspot counts as a reliable measure of an approximate 22-year cycle for most of that time. This record is why the "Maunder Minimum" is now known to have happened simultaneous with the "little Ice Age" of 1700 and less reliably as a proxy recording other protracted solar minima occurring simultaneous to drawn-out cooling here on Earth, perhaps like the one during the early 14th century that might be connected with poor growing conditions, famine and even those conditions that helped the Black Plague of 1349 that may have wiped out a third of Earth's human population with marked efficiency, helped, of course, by the general ignorance of contagion of that brutal time.
No one alive today has experienced a solar minimum deeper than the one that bottomed out (finally) in 2009.
A search on-line for one of those elementary science book graphs that illustrate the rise and fall of solar activity will show cycles generally increasing in strength at their peak, cycle after cycle, during the 20th century. Many of us can remember upon our first look upon such graphs thinking "how long will this go on."
Would solar activity, a precise measure of the Interplanetary Magnetic Field, continue increasing forever, we wondered? Pretty unlikely, since the direct correlation between the Sun's business and our long survival as neighbors nearby, though not thought about much by movie makers preferring dark meteors and aliens, is the most likely influence from "beyond" affecting life on Earth.
What could be more obvious? Though it is invisible to the naked eye barely a mere 50 light years away, our small yellow dwarf star is a long-period variable. We know so little about the variability of small star like our Sun because there are so many brighter, short-period variables to study, many in galaxies far, far away. Stars like ours don't stand out from the hazy crowd at such distances. Or study of Solar Physics is just getting started, and the Sun may be preparing us for classes of its own.
Conventional wisdom holds that, except for the more obvious dangers, the greatest ionizing radiation hazard facing astronauts headed to the Moon, say, is a coronal mass ejection or X-flare event.
On the contrary, however, the thin skin of the aluminum composite making up the hull of the spacecraft in our time provides a pretty fair shield against solar "events." That's really not the radiation that makes travel to Mars dangerous, for example. Space is very unforgiving of hubris, and no amount of burying our heads in the regolith will change the fact that the really hard radiation arriving in the inner solar system from interstellar space, the so-called Galactic Cosmic Rays, or "GSR's" - comes in very big packets of heavy elemental particles.
The skin of an Apollo Command Module doesn't help, it hinders, when protecting against radiation of that magnitude. Far from shielding a traveler from that kind of radiation, the ionizing nuclei of heavy elements traveling at near the speed of light instead are broken apart by a modern spacecraft hull, and afterward expose a living passenger to a shot-gun blast of ionizing secondary particles.
And once an astronaut's exposure has been rated sufficiently high to increase his life-time risk of "Radiation Exposure Induced Death" (or "REID) reaches beyond odds of 4 percent they're grounded. That's NASA policy.
There has been a lot of progress, some genuinely good ideas for designs for shielding astronauts traveling beyond the Moon from the broad spectrum of hard cosmic rays. At least advocates of travel to Mars, for example, have begun integrating some good ideas for protecting a living crew from cosmic rays into notional spacecraft.
A magnetic field like Earth's produced by a spacecraft would need to begin refracting an average cosmic ray more than 2,000 kilometers away for there to be sufficient bending of its vector away from striking home. That's a tall order in mass and energy, one served up by Earth every moment and backed up by our watery atmosphere.
Carrying a water-filled tank or surrounding passengers with a skin of water is a tall order in mass and engineering, also. It would be a lot easier to ship that water from the Moon's gravity well than up from here on Earth. There might be secondary engineering and life support advantages to such a scheme also, but forget about running to a tank for protection from a "shower" of cosmic rays.
Unlike solar storms, cosmic rays arrive from every direction without predictability, except for one measurable factor. Right now the best protection we have against cosmic rays is the very Interplanetary Magnetic Field whose strength corresponds with the Sun's activity.
When the Sun is at its most active the arrival of cosmic rays from outside the solar system in the vicinity of Earth is at a minimum. The correlation is well established as an inverse relationship. When the Sun is at minimum the incidence of cosmic ray bombardment here increases by half. Put another way, the Interplanetary Magnetic Field at greatest measured strength reduces the incidence of Galactic Cosmic Rays at Earth by 50 percent.
It will continue to be interesting to measure cosmic ray bombardment from the periphery of the Solar System.
The cosmic ray detectors on-board both of the 30-year-old Voyager spacecraft are the only experiments still delivering daily readings of this activity from their locations at the weak edge of the Sun's influence.
Here on Earth, where the incidence of Cosmic Radiation has been measured continuously since 1958, the highest peak in that activity (measured on the surface, where only very energetic radiation survives the trip through our own planet's magnetic field, our Van Allen Belts and atmosphere) reached its highest level ever recorded in 2009, precisely the same moment when the Sun's own "activity" was at its most recent protracted minimum.
The instant measurement of the beginning of a fall off in cosmic ray bombardment was one of the first real signs that showed Cycle 24 was finally getting started (though five years overdue).
Predictions made for a couple of hard winters following a latency following after that minimum have proven to be surprisingly accurate, though that latency would seem to call for severe winters (if certain hypothesis actually has meaning) three years after this last long minima.
The previous recorded record for cosmic ray bombardment, more than 10 percent less "severe" than the one just ended, took place around 1964, not long after real monitoring of this activity started. The last time snow drifts higher than two meters were recorded as far south as Washington, DC took place in 1966 - that is until this past winter.
The coincidence of a weak Interplanetary Magnetic Field with harsh winters has shown itself to be predictable, though these predictions have yet to survive stringent inquiry. It's a very broad correlation, at best, and one that does not exclude the false spring or warm February or predict any short-term weather.
But for travel beyond the Moon, beyond where our Moon itself provides an immediate shielding from a full 50 percent of interstellar radiation, and places to bury oneself at least 11 meters below the immediate surface, things are not looking up, except for the most optimistic and determined starry-eyed misfit space enthusiast.
A trip to a place as seemingly and conveniently close as Mars (where the same kinds of shielding available on the Moon can be found, including water) the round-trip using "off-the-shelf" technologies assures an astronaut would be grounded for life upon his or her return. And, oddly, the younger the crew the higher the odds of death, over the course of an individual's lifespan of Radiation Exposure Induced Death.
It looks very much like Deep Space travel is even more likely than ever before headed toward becoming a game for older people, more likely to die of natural causes before succumbing REID. And, yes, such factors are already a part of the scheme by which NASA runs those numbers.
The outcome of these predictions, should they pan out, is grim for Deep Space travel. A little problem nagging those who want to brave the trip to Mars and back, skipping ahead of the class by ignoring what the Moon has been waiting to teach us since the United States Congress made the decision to drop out in 1971, may be coming into focus a lot more rapidly than any of us hoped.
These reputable long-term studies back-up predictions - dismissed at the time - that the Sun was literally winding up, and was overdue, for one of those poorly understood but historically recorded periods of relative quiet.
Whether this means a Maunder Minimum, with effects on Earth like a "little Ice Age," as took place in the late 17th and early 18th centuries, is not the immediate story, yet. I think the big story will be a change in our thinking about the Sun's cyclical behavior, its long-period cyclical behavior.
Most of us, at one point or another, have seen the charts showing the 22-years solar cycle plotted out for at least the last century or less. Sunspots are a secondary effect of what's really being measured. They are a visible manifestation of solar maximum, not the thing itself. An outwardly bright showing of the tightly wound magnetic field of the Sun generated deep within its interior.
The Sun is not a solid, and parts of this "mass of incandescent gas" are rotating around its axis a differing speeds, generating magnetic fields that break apart and sometime oppose one another with violence we poorly imagine.
But, as a recordable phenomena in the historic records here in the West since A.D. 1645 we have been able to use sunspot counts as a reliable measure of an approximate 22-year cycle for most of that time. This record is why the "Maunder Minimum" is now known to have happened simultaneous with the "little Ice Age" of 1700 and less reliably as a proxy recording other protracted solar minima occurring simultaneous to drawn-out cooling here on Earth, perhaps like the one during the early 14th century that might be connected with poor growing conditions, famine and even those conditions that helped the Black Plague of 1349 that may have wiped out a third of Earth's human population with marked efficiency, helped, of course, by the general ignorance of contagion of that brutal time.
No one alive today has experienced a solar minimum deeper than the one that bottomed out (finally) in 2009.
A search on-line for one of those elementary science book graphs that illustrate the rise and fall of solar activity will show cycles generally increasing in strength at their peak, cycle after cycle, during the 20th century. Many of us can remember upon our first look upon such graphs thinking "how long will this go on."
Would solar activity, a precise measure of the Interplanetary Magnetic Field, continue increasing forever, we wondered? Pretty unlikely, since the direct correlation between the Sun's business and our long survival as neighbors nearby, though not thought about much by movie makers preferring dark meteors and aliens, is the most likely influence from "beyond" affecting life on Earth.
What could be more obvious? Though it is invisible to the naked eye barely a mere 50 light years away, our small yellow dwarf star is a long-period variable. We know so little about the variability of small star like our Sun because there are so many brighter, short-period variables to study, many in galaxies far, far away. Stars like ours don't stand out from the hazy crowd at such distances. Or study of Solar Physics is just getting started, and the Sun may be preparing us for classes of its own.
Conventional wisdom holds that, except for the more obvious dangers, the greatest ionizing radiation hazard facing astronauts headed to the Moon, say, is a coronal mass ejection or X-flare event.
On the contrary, however, the thin skin of the aluminum composite making up the hull of the spacecraft in our time provides a pretty fair shield against solar "events." That's really not the radiation that makes travel to Mars dangerous, for example. Space is very unforgiving of hubris, and no amount of burying our heads in the regolith will change the fact that the really hard radiation arriving in the inner solar system from interstellar space, the so-called Galactic Cosmic Rays, or "GSR's" - comes in very big packets of heavy elemental particles.
The skin of an Apollo Command Module doesn't help, it hinders, when protecting against radiation of that magnitude. Far from shielding a traveler from that kind of radiation, the ionizing nuclei of heavy elements traveling at near the speed of light instead are broken apart by a modern spacecraft hull, and afterward expose a living passenger to a shot-gun blast of ionizing secondary particles.
And once an astronaut's exposure has been rated sufficiently high to increase his life-time risk of "Radiation Exposure Induced Death" (or "REID) reaches beyond odds of 4 percent they're grounded. That's NASA policy.
There has been a lot of progress, some genuinely good ideas for designs for shielding astronauts traveling beyond the Moon from the broad spectrum of hard cosmic rays. At least advocates of travel to Mars, for example, have begun integrating some good ideas for protecting a living crew from cosmic rays into notional spacecraft.
A magnetic field like Earth's produced by a spacecraft would need to begin refracting an average cosmic ray more than 2,000 kilometers away for there to be sufficient bending of its vector away from striking home. That's a tall order in mass and energy, one served up by Earth every moment and backed up by our watery atmosphere.
Carrying a water-filled tank or surrounding passengers with a skin of water is a tall order in mass and engineering, also. It would be a lot easier to ship that water from the Moon's gravity well than up from here on Earth. There might be secondary engineering and life support advantages to such a scheme also, but forget about running to a tank for protection from a "shower" of cosmic rays.
Unlike solar storms, cosmic rays arrive from every direction without predictability, except for one measurable factor. Right now the best protection we have against cosmic rays is the very Interplanetary Magnetic Field whose strength corresponds with the Sun's activity.
When the Sun is at its most active the arrival of cosmic rays from outside the solar system in the vicinity of Earth is at a minimum. The correlation is well established as an inverse relationship. When the Sun is at minimum the incidence of cosmic ray bombardment here increases by half. Put another way, the Interplanetary Magnetic Field at greatest measured strength reduces the incidence of Galactic Cosmic Rays at Earth by 50 percent.
It will continue to be interesting to measure cosmic ray bombardment from the periphery of the Solar System.
The cosmic ray detectors on-board both of the 30-year-old Voyager spacecraft are the only experiments still delivering daily readings of this activity from their locations at the weak edge of the Sun's influence.
Here on Earth, where the incidence of Cosmic Radiation has been measured continuously since 1958, the highest peak in that activity (measured on the surface, where only very energetic radiation survives the trip through our own planet's magnetic field, our Van Allen Belts and atmosphere) reached its highest level ever recorded in 2009, precisely the same moment when the Sun's own "activity" was at its most recent protracted minimum.
The instant measurement of the beginning of a fall off in cosmic ray bombardment was one of the first real signs that showed Cycle 24 was finally getting started (though five years overdue).
Predictions made for a couple of hard winters following a latency following after that minimum have proven to be surprisingly accurate, though that latency would seem to call for severe winters (if certain hypothesis actually has meaning) three years after this last long minima.
The previous recorded record for cosmic ray bombardment, more than 10 percent less "severe" than the one just ended, took place around 1964, not long after real monitoring of this activity started. The last time snow drifts higher than two meters were recorded as far south as Washington, DC took place in 1966 - that is until this past winter.
The coincidence of a weak Interplanetary Magnetic Field with harsh winters has shown itself to be predictable, though these predictions have yet to survive stringent inquiry. It's a very broad correlation, at best, and one that does not exclude the false spring or warm February or predict any short-term weather.
But for travel beyond the Moon, beyond where our Moon itself provides an immediate shielding from a full 50 percent of interstellar radiation, and places to bury oneself at least 11 meters below the immediate surface, things are not looking up, except for the most optimistic and determined starry-eyed misfit space enthusiast.
A trip to a place as seemingly and conveniently close as Mars (where the same kinds of shielding available on the Moon can be found, including water) the round-trip using "off-the-shelf" technologies assures an astronaut would be grounded for life upon his or her return. And, oddly, the younger the crew the higher the odds of death, over the course of an individual's lifespan of Radiation Exposure Induced Death.
It looks very much like Deep Space travel is even more likely than ever before headed toward becoming a game for older people, more likely to die of natural causes before succumbing REID. And, yes, such factors are already a part of the scheme by which NASA runs those numbers.
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