Radiation Problem - Revision history

24.42.191.163: /* Corona Mass Ejections */

2013-04-27T16:57:50Z

Corona Mass Ejections

Jotagiraldez at 13:09, 25 November 2010

2010-11-25T13:09:50Z

Farred: /* Radon Gas */

2010-06-21T21:13:26Z

Radon Gas

Farred: /* Direct Radiation */ insufficiency of thin protection

2010-06-21T20:18:29Z

Direct Radiation: insufficiency of thin protection

Farred: explained in talk section

2010-06-21T20:01:16Z

explained in talk section

93.102.74.7: /* Protection Provide by Earth */

2010-06-21T18:07:52Z

Protection Provide by Earth

Jriley: /* Ionized Gas */

2009-07-10T13:11:08Z

Ionized Gas

Jriley: /* Corona Mass Ejections */

2009-07-10T13:09:39Z

Corona Mass Ejections

Jriley: /* The Mass of the Atmosphere */

2009-07-10T13:07:50Z

The Mass of the Atmosphere

Jriley: /* Corona Mass Ejections */

2009-07-10T12:58:39Z

Corona Mass Ejections

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-===Corona Mass Ejections===
+===Coronal Mass Ejections===
-The Sun has major storms, called [[Corona Mass Ejections]] (CME), which dump large amounts of radiation out into space.  These space weather storms are associated with large sun spots and can do a great deal of damage to utilities on Earth, and to our satellites.  These storms can be expected to hit a settlement on the [[Moon]] from 0 to 5 times a year.
+The Sun has major storms, called [[Coronal Mass Ejections]] (CME), which dump large amounts of radiation out into space.  These space weather storms are associated with large sun spots and can do a great deal of damage to utilities on Earth, and to our satellites.  These storms can be expected to hit a settlement on the [[Moon]] from 0 to 5 times a year.
 ====High Energy Electrons====

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 ----
-The Earth provides two types of radiation shielding critical for life: atmospheric mass and magnetic field.  The Moon has neither type.  On the Moon, our architecture must provide all our shielding, see [[Architecture List]]. Any lunar settlement design that does not address the radiation problem should simply be rejected as unsafe.
+The Earth provides two types of [[list of shielding options|radiation shielding]] critical for life: atmospheric mass and magnetic field.  The Moon has neither type.  On the Moon, our architecture must provide all our shielding, see [[Architecture List]]. Any lunar settlement design that does not address the radiation problem should simply be rejected as unsafe. The radiation hazards on the moon includes all the spectrum of radiation ([[Non-Ionizing Radiation]] and [[Ionizing radiation]]).
 ==Protection Provide by Earth==
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 # [[http://science.nasa.gov/headlines/y2007/25may_costep.htm The Ions are Coming!]] discusses the the monitoring of solar electrons to predict more problematic radiation.
 <BR clear="all"/>

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 Another source of dangerous radiation is the radon gas that is created in the decay of trace amounts of uranium found naturally in lunar rocks.  This gas is very heavy and concentrates in low areas.  This type of radiation is easily stopped by even a thin layer of material, but radon is carcinogenic if ingested directly into the body.
-The output of any process to recover volitilies from lunar regolith must be routinely checked for radon gas.
+Even though sensitive scientific equipment has been able to detect radon on Luna, the quantity of radon gas is such that it can be ignored.  The [[Lunar atmosphere|lunar atmosphere]] is so thin that the most massive component, Argon, is present in only 30,000 particles per cubic centimeter, that is 2 trillionths of a gram per cubic meter.  Radon is so scarce that it is not even mentioned in the list of components in the lunar atmosphere article.  See the [http://nssdc.gsfc.nasa.gov/planetary/factsheet/moonfact.html| Moon Fact Sheet] from NASA.
 Radon has also been detected from [[lunar outgassing]] events.

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 The storms provide two distinct forms of radiation danger.  First they put out a great surge of [[high energy particles]] that expand out at a substantial fraction of the speed of light.  Our warning system will provide only 30 to 40 minutes of warning for this danger.  Anyone caught out on the surface will be subject to a severe health threat.  This danger only lasts a few hours.
-This form of radiation is a special problem.  It actually generates [[secondary radiation]] in the first layer of [[mass shielding]].  To protect against the high energy particles and the secondary particles they generate takes six to ten meters of [[regolith]].  Thicknesses in between are not much help.
+This form of radiation is a special problem.  It actually generates [[secondary radiation]] in the first layer of [[mass shielding]].  To protect against the high energy particles and the secondary particles they generate takes six to ten meters of [[regolith]].  Thicknesses less than six meters do not protect from Corona Mass Ejections.
 [[Image:ArchDorm01.jpg|frame|Architecture as Mole Hills, Standard dorm room]]
 ====Ionized Gas====

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 ===The Earth's magnetic field===
-The third shield is the Earth's magnetic field.  This field diverts most of the radiation coming from the Sun into the Van Allen belts.  The Moon has no such field and is, for the larger part of its orbit, outside the Earth's field.  There is no practical way to generate such a field around a lunar settlement.
+The second shield is the Earth's magnetic field.  This field diverts most of the radiation coming from the Sun into the Van Allen belts.  The Moon has no such field and is, for the larger part of its orbit, outside the Earth's field.  There is no practical way to generate such a field around a lunar settlement.
 ==The Solar Challange==

← Older revision		Revision as of 13:11, 10 July 2009
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−	The second form of [[solar radiation]] is the mass of [[ionized gas]] thrown out by the CME. Composed mostly of ionized [[hydrogen]] these clouds have a mass equivalent to a large mountain and are the source of the volatiles that may be mined from the lunar [[regolith]]. These storms follow a curved path so the ones that hit any site on the the [[Moon]] ~~are~~ not the ones associated with direct radiation storms at that same site.	+	The second form of [[solar radiation]] is the mass of [[ionized gas]] thrown out by the CME. Composed mostly of ionized [[hydrogen]] these clouds have a mass equivalent to a large mountain and are the source of the volatiles that may be mined from the lunar [[regolith]]. These storms follow a curved path so the ones that hit any site on the the [[Moon]] may not be the ones associated with direct radiation storms at that same site.

	The good news is that we will have 24 to 48 hours warning about this form of radiation storm. They will then last 24 to 72 hours. These will be very dangerous for people doing outside operations but a thick regolith shield can provide acceptable levels of protection.		The good news is that we will have 24 to 48 hours warning about this form of radiation storm. They will then last 24 to 72 hours. These will be very dangerous for people doing outside operations but a thick regolith shield can provide acceptable levels of protection.

← Older revision		Revision as of 13:09, 10 July 2009
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	The Sun has major storms, called [[Corona Mass Ejections]] (CME), which dump large amounts of radiation out into space. These space weather storms are associated with large sun spots and can do a great deal of damage to utilities on Earth, and to our satellites. These storms can be expected to hit a settlement on the [[Moon]] from 0 to 5 times a year.		The Sun has major storms, called [[Corona Mass Ejections]] (CME), which dump large amounts of radiation out into space. These space weather storms are associated with large sun spots and can do a great deal of damage to utilities on Earth, and to our satellites. These storms can be expected to hit a settlement on the [[Moon]] from 0 to 5 times a year.
		+
		+	====High Energy Electrons====

	Fortunately a wave of high energy electrons proceeds most solar storms. These particles will not penetrate even thin electrically conductive shielding and so are not very dangerous while they can provide good early warning. Satellites and lunar based equipment that monitor the sun can provide more advanced warnings. All equipment on the lunar surface must be designed to withstand these events.		Fortunately a wave of high energy electrons proceeds most solar storms. These particles will not penetrate even thin electrically conductive shielding and so are not very dangerous while they can provide good early warning. Satellites and lunar based equipment that monitor the sun can provide more advanced warnings. All equipment on the lunar surface must be designed to withstand these events.

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 ===The Mass of the Atmosphere===
-The first shield is simply the mass of the atmosphere which simply blocks radiation.  The Earth's atmosphere has a mass equivalent to about 32 feet of water.  It will take a layer of at least two meters of lunar regolith to match this mass and more is better.  A blanket of two meters of regolith provides about the mass protection for a person living in a high altitude city like Denver or Mexico City.  For a more detailed discussion please see [[Roof Support]] for inflatable lunar structures.
+The first shield is simply the mass of the atmosphere which simply blocks radiation.  The Earth's atmosphere has a mass equivalent to about 32 feet of water.  A blanket of two meters of regolith provides the protection needed against the background lunar radiation but more is needed for the occasional major radiation events.  For a more detailed discussion please see [[Roof Support]] for inflatable lunar structures.
 ===The Earth's magnetic field===

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 The Sun has major storms, called [[Corona Mass Ejections]] (CME), which dump large amounts of radiation out into space.  These space weather storms are associated with large sun spots and can do a great deal of damage to utilities on Earth, and to our satellites.  These storms can be expected to hit a settlement on the [[Moon]] from 0 to 5 times a year.
-Fortunately a wave of high energy electrons proceeds most solar storms.  These particles will not penetrate even thin electrically conductive shielding and so are not very dangerous while they provide good early warning.  Satellites and lunar based equipment that monitor the sun can provide more advanced warnings.
+Fortunately a wave of high energy electrons proceeds most solar storms.  These particles will not penetrate even thin electrically conductive shielding and so are not very dangerous while they can provide good early warning.  Satellites and lunar based equipment that monitor the sun can provide more advanced warnings.  All equipment on the lunar surface must be designed to withstand these events.
 ====Direct Radiation====