Sunlight - Revision history

Michel Lamontagne: typos and such

2024-11-05T16:09:24Z

typos and such

RichardWSmith: /* Psychological and physiological effects of sunlight */ Fixed link.

2024-10-30T00:27:46Z

Psychological and physiological effects of sunlight: Fixed link.

← Older revision		Revision as of 01:27, 30 October 2024
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	*The generally lower levels of sunshine may require the use of artificial lighting to treat seasonal depression disorder, as in commonly done in Northern countries on Earth.		*The generally lower levels of sunshine may require the use of artificial lighting to treat seasonal depression disorder, as in commonly done in Northern countries on Earth.
	*The lower lighting levels will affect plants and reduce their agricultural yield and rate of growth.		*The lower lighting levels will affect plants and reduce their agricultural yield and rate of growth.
	*Humans can make vitamin D via [[Ultraviolet ~~light~~]] in our skins. Unless there are UV lights inside the base, humans will need to take vitamin supplements.		*Humans can make vitamin D via [[Ultraviolet]] light in our skins. Unless there are UV lights inside the base, humans will need to take vitamin supplements.
	*What are the psychological and physiological effects of the permanent dim light on [[human]]s, [[animals]] and plants?		*What are the psychological and physiological effects of the permanent dim light on [[human]]s, [[animals]] and plants?

RichardWSmith: /* Psychological and physiological effects of sunlight */ Vitamin D deficiency.

2024-10-30T00:26:40Z

Psychological and physiological effects of sunlight: Vitamin D deficiency.

← Older revision		Revision as of 01:26, 30 October 2024
Line 23:		Line 23:
	*The generally lower levels of sunshine may require the use of artificial lighting to treat seasonal depression disorder, as in commonly done in Northern countries on Earth.		*The generally lower levels of sunshine may require the use of artificial lighting to treat seasonal depression disorder, as in commonly done in Northern countries on Earth.
	*The lower lighting levels will affect plants and reduce their agricultural yield and rate of growth.		*The lower lighting levels will affect plants and reduce their agricultural yield and rate of growth.
			*Humans can make vitamin D via [[Ultraviolet light]] in our skins. Unless there are UV lights inside the base, humans will need to take vitamin supplements.
	*What are the psychological and physiological effects of the permanent dim light on [[human]]s, [[animals]] and plants?		*What are the psychological and physiological effects of the permanent dim light on [[human]]s, [[animals]] and plants?

RichardWSmith: /* Facts and figures */ Made sentence more accurate.

2024-10-30T00:24:53Z

Facts and figures: Made sentence more accurate.

← Older revision		Revision as of 01:24, 30 October 2024
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	"in the UK we receive an average power of about 125 Wm<sup>-2</sup> whilst the Sahara Desert gets 250-300 Wm<sup>-2</sup>" <ref>[http://cms.ises.org/uploads2/SSF/pictures/materials/307/solarrad.PDF the SOLAR ENERGY society: Solar Radiation - Distribution and Availability of Solar Energy]</ref>. With 24*365 hours per year, this results in an average usable energy per m<sup>2</sup> and year of 1095 kWh in the UK and 2190-2628 kWh in the Sahara.		"in the UK we receive an average power of about 125 Wm<sup>-2</sup> whilst the Sahara Desert gets 250-300 Wm<sup>-2</sup>" <ref>[http://cms.ises.org/uploads2/SSF/pictures/materials/307/solarrad.PDF the SOLAR ENERGY society: Solar Radiation - Distribution and Availability of Solar Energy]</ref>. With 24*365 hours per year, this results in an average usable energy per m<sup>2</sup> and year of 1095 kWh in the UK and 2190-2628 kWh in the Sahara.

	The Mars solar constant is 590 W/m3, while the Earth solar constant is 1350 W/m2. Mars gets ~~about~~ half the sunlight Earth does. The Martian atmosphere is dusty; the usable energy at the Mars equator may be about 1100-1300 kWh per year per m2 (3960 to 4680 MJ), or somewhat like England or Northern Europe. For 22% efficient solar cells this would translate to about 240-286 kWh/year/m2.		The Mars solar constant is 590 W/m3, while the Earth solar constant is 1350 W/m2. Mars gets a bit less than half the sunlight Earth does. The Martian atmosphere is dusty; the usable energy at the Mars equator may be about 1100-1300 kWh per year per m2 (3960 to 4680 MJ), or somewhat like England or Northern Europe. For 22% efficient solar cells this would translate to about 240-286 kWh/year/m2.

	==Psychological and physiological effects of sunlight==		==Psychological and physiological effects of sunlight==

RichardWSmith: Note that there is enough sunlight on Mars for crops.. out to asteroid belt.

2024-09-13T13:07:36Z

Note that there is enough sunlight on Mars for crops.. out to asteroid belt.

← Older revision		Revision as of 14:07, 13 September 2024
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	The [[Sun]] is on average 228 million km away from [[Mars]]. '''Sunlight''' takes 13 minutes to travel from the Sun to Mars with a power of 589 W/m<sup>2</sup>. It is ~~not~~ as bright as on [[Earth]] (1367 W/m<sup>2</sup>).		The [[Sun]] is on average 228 million km away from [[Mars]]. '''Sunlight''' takes 13 minutes to travel from the Sun to Mars with a power of 589 W/m<sup>2</sup>. It is only 43% as bright as on [[Earth]] (1367 W/m<sup>2</sup>).
	[[Image:sunset.jpg\|thumb\|right\|300px\|Sunset photographed by Mars Rover Spirit]]		[[Image:sunset.jpg\|thumb\|right\|300px\|Sunset photographed by Mars Rover Spirit]]

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	Due to the dust, sunlight on Mars is usually fairly diffuse. It comes from many directions at once, rather than directly from the sun. Rather like an overcast day on Earth. This makes it harder to concentrate sunlight using reflectors <ref>https://ntrs.nasa.gov/api/citations/19890018252/downloads/19890018252.pdf</ref>.		Due to the dust, sunlight on Mars is usually fairly diffuse. It comes from many directions at once, rather than directly from the sun. Rather like an overcast day on Earth. This makes it harder to concentrate sunlight using reflectors <ref>https://ntrs.nasa.gov/api/citations/19890018252/downloads/19890018252.pdf</ref>.

	Sunlight can be used for [[electricity\|power generation]] by [[solar panel]]s and for growing [[plants]] in [[greenhouse]]s. It may also be used to warm a colony, especially if the habitat has [[Smart Windows]].		Sunlight can be used for [[electricity\|power generation]] by [[solar panel]]s and for growing [[plants]] in [[greenhouse]]s. It may also be used to warm a colony, especially if the habitat has [[Smart Windows]].

			Note that the sunlight is bright enough for growing plants (tho they may grow slower). There is enough sunlight for crops out to the asteroid belt, but at Jupiter and further from the sun, artificial lights are needed for crops.

	==Facts and figures==		==Facts and figures==

RichardWSmith: Added link to Smart windows.

2024-09-04T23:14:30Z

Added link to Smart windows.

← Older revision		Revision as of 00:14, 5 September 2024
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	As shown by the images transmitted by the various probes and rovers, the sky is caramel colored most of the time. At sunrise and sunset, the sky can be blue near the horizon, as per the Spirit photograph. This is due to sun scattering of other wavelength by the dust in the Martian atmosphere.		As shown by the images transmitted by the various probes and rovers, the sky is caramel colored most of the time. At sunrise and sunset, the sky can be blue near the horizon, as per the Spirit photograph. This is due to sun scattering of other wavelength by the dust in the Martian atmosphere.

	The Martian [[atmosphere]] does not filter sunlight as efficiently as on Earth, leaving too much UV ray and high energy particles to reach the surface. Life directly on the Martian surface is considered unlikely without additional shielding against UVs and [[cosmic radiation]] from the solar winds. An[[Early warning system for solar radiation\|early warning system]]) may be useful for an eventual settlement.		The Martian [[atmosphere]] does not filter sunlight as efficiently as on Earth, leaving too much UV ray and high energy particles to reach the surface. Life directly on the Martian surface is considered unlikely without additional shielding against UVs and [[cosmic radiation]] from the solar winds. An [[Early warning system for solar radiation\|early warning system]]) may be useful for an eventual settlement.

	The amount of usable energy on the surface is much lower than the solar constant due to the rotation of the planet and is also reduced the furter away you are from the equator due to the incident angle of the light at the surface. Reflection and absorption ([[albedo]]) in the atmosphere must be considered. On Earth, the annual usable energy per m<sup>2</sup> is about 1000 kWh/y in Middle Europe and 2400 kWh/y in the Sahara.		The amount of usable energy on the surface is much lower than the solar constant due to the rotation of the planet and is also reduced the furter away you are from the equator due to the incident angle of the light at the surface. Reflection and absorption ([[albedo]]) in the atmosphere must be considered. On Earth, the annual usable energy per m<sup>2</sup> is about 1000 kWh/y in Middle Europe and 2400 kWh/y in the Sahara.
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	Due to the dust, sunlight on Mars is usually fairly diffuse. It comes from many directions at once, rather than directly from the sun. Rather like an overcast day on Earth. This makes it harder to concentrate sunlight using reflectors <ref>https://ntrs.nasa.gov/api/citations/19890018252/downloads/19890018252.pdf</ref>.		Due to the dust, sunlight on Mars is usually fairly diffuse. It comes from many directions at once, rather than directly from the sun. Rather like an overcast day on Earth. This makes it harder to concentrate sunlight using reflectors <ref>https://ntrs.nasa.gov/api/citations/19890018252/downloads/19890018252.pdf</ref>.

	Sunlight can be used for [[electricity\|power generation]] by [[solar panel]]s and for growing [[plants]] in [[greenhouse]]s.		Sunlight can be used for [[electricity\|power generation]] by [[solar panel]]s and for growing [[plants]] in [[greenhouse]]s. It may also be used to warm a colony, especially if the habitat has [[Smart Windows]].

	==Facts and figures==		==Facts and figures==

Michel Lamontagne: /* Psychological and physiological effects of sunlight */

2024-09-04T17:29:16Z

Psychological and physiological effects of sunlight

← Older revision		Revision as of 18:29, 4 September 2024
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	*The generally lower levels of sunshine may require the use of artificial lighting to treat seasonal depression disorder, as in commonly done in Northern countries on Earth.		*The generally lower levels of sunshine may require the use of artificial lighting to treat seasonal depression disorder, as in commonly done in Northern countries on Earth.
	*The lower lighting levels ~~may~~ affect plants and reduce their agricultural yield and rate of growth.		*The lower lighting levels will affect plants and reduce their agricultural yield and rate of growth.

	*What are the psychological and physiological effects of the permanent dim light on [[human]]s, [[animals]] and plants?		*What are the psychological and physiological effects of the permanent dim light on [[human]]s, [[animals]] and plants?


	==References==		==References==

Michel Lamontagne: /* Facts and figures */

2024-09-04T17:27:29Z

Facts and figures

← Older revision		Revision as of 18:27, 4 September 2024
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	"in the UK we receive an average power of about 125 Wm<sup>-2</sup> whilst the Sahara Desert gets 250-300 Wm<sup>-2</sup>" <ref>[http://cms.ises.org/uploads2/SSF/pictures/materials/307/solarrad.PDF the SOLAR ENERGY society: Solar Radiation - Distribution and Availability of Solar Energy]</ref>. With 24*365 hours per year, this results in an average usable energy per m<sup>2</sup> and year of 1095 kWh in the UK and 2190-2628 kWh in the Sahara.		"in the UK we receive an average power of about 125 Wm<sup>-2</sup> whilst the Sahara Desert gets 250-300 Wm<sup>-2</sup>" <ref>[http://cms.ises.org/uploads2/SSF/pictures/materials/307/solarrad.PDF the SOLAR ENERGY society: Solar Radiation - Distribution and Availability of Solar Energy]</ref>. With 24*365 hours per year, this results in an average usable energy per m<sup>2</sup> and year of 1095 kWh in the UK and 2190-2628 kWh in the Sahara.

	The Mars solar constant is 590 W/m3, while the Earth solar constant is 1350 W/m2. Mars gets about half the sunlight Earth does. The Martian atmosphere is dusty; the usable energy at the Mars equator may be about 1100-1300 kWh per year per m2, or somewhat like England or Northern Europe.		The Mars solar constant is 590 W/m3, while the Earth solar constant is 1350 W/m2. Mars gets about half the sunlight Earth does. The Martian atmosphere is dusty; the usable energy at the Mars equator may be about 1100-1300 kWh per year per m2 (3960 to 4680 MJ), or somewhat like England or Northern Europe. For 22% efficient solar cells this would translate to about 240-286 kWh/year/m2.

	==Psychological and physiological effects of sunlight==		==Psychological and physiological effects of sunlight==

Michel Lamontagne at 14:30, 4 September 2024

2024-09-04T14:30:43Z

← Older revision		Revision as of 15:30, 4 September 2024
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	The Martian [[atmosphere]] does not filter sunlight as efficiently as on Earth, leaving too much UV ray and high energy particles to reach the surface. Life directly on the Martian surface is considered unlikely without additional shielding against UVs and [[cosmic radiation]] from the solar winds. An[[Early warning system for solar radiation\|early warning system]]) may be useful for an eventual settlement.		The Martian [[atmosphere]] does not filter sunlight as efficiently as on Earth, leaving too much UV ray and high energy particles to reach the surface. Life directly on the Martian surface is considered unlikely without additional shielding against UVs and [[cosmic radiation]] from the solar winds. An[[Early warning system for solar radiation\|early warning system]]) may be useful for an eventual settlement.

	The amount of usable energy on the surface is much lower than the solar constant due to the rotation of the planet and is also reduced the furter away you are from the equator due to the incident angle of the light at the surface. Reflection and absorption ([[albedo]]) in the atmosphere must be considered. On Earth, the annual usable energy per m<sup>2</sup> is about 1000 kWh in Middle Europe and 2400 kWh in the Sahara.		The amount of usable energy on the surface is much lower than the solar constant due to the rotation of the planet and is also reduced the furter away you are from the equator due to the incident angle of the light at the surface. Reflection and absorption ([[albedo]]) in the atmosphere must be considered. On Earth, the annual usable energy per m<sup>2</sup> is about 1000 kWh/y in Middle Europe and 2400 kWh/y in the Sahara.

	Due to the dust, sunlight on Mars is usually fairly diffuse. It comes from many directions at once, rather than directly from the sun. Rather like an overcast day on Earth. This makes it harder to concentrate sunlight using reflectors <ref>https://ntrs.nasa.gov/api/citations/19890018252/downloads/19890018252.pdf</ref>.		Due to the dust, sunlight on Mars is usually fairly diffuse. It comes from many directions at once, rather than directly from the sun. Rather like an overcast day on Earth. This makes it harder to concentrate sunlight using reflectors <ref>https://ntrs.nasa.gov/api/citations/19890018252/downloads/19890018252.pdf</ref>.

Michel Lamontagne at 14:29, 4 September 2024

2024-09-04T14:29:48Z

← Older revision		Revision as of 15:29, 4 September 2024
Line 8:		Line 8:
	The amount of usable energy on the surface is much lower than the solar constant due to the rotation of the planet and is also reduced the furter away you are from the equator due to the incident angle of the light at the surface. Reflection and absorption ([[albedo]]) in the atmosphere must be considered. On Earth, the annual usable energy per m<sup>2</sup> is about 1000 kWh in Middle Europe and 2400 kWh in the Sahara.		The amount of usable energy on the surface is much lower than the solar constant due to the rotation of the planet and is also reduced the furter away you are from the equator due to the incident angle of the light at the surface. Reflection and absorption ([[albedo]]) in the atmosphere must be considered. On Earth, the annual usable energy per m<sup>2</sup> is about 1000 kWh in Middle Europe and 2400 kWh in the Sahara.

	Due to the dust, sunlight on Mars is usually fairly diffuse. It comes from many directions at once, rather than directly from the sun. Rather like an overcast day on Earth. This makes it harder to concentrate sunlight using reflectors.		Due to the dust, sunlight on Mars is usually fairly diffuse. It comes from many directions at once, rather than directly from the sun. Rather like an overcast day on Earth. This makes it harder to concentrate sunlight using reflectors <ref>https://ntrs.nasa.gov/api/citations/19890018252/downloads/19890018252.pdf</ref>.

	Sunlight can be used for [[electricity\|power generation]] by [[solar panel]]s and for growing [[plants]] in [[greenhouse]]s.		Sunlight can be used for [[electricity\|power generation]] by [[solar panel]]s and for growing [[plants]] in [[greenhouse]]s.

← Older revision		Revision as of 17:09, 5 November 2024
Line 4:		Line 4:
	As shown by the images transmitted by the various probes and rovers, the sky is caramel colored most of the time. At sunrise and sunset, the sky can be blue near the horizon, as per the Spirit photograph. This is due to sun scattering of other wavelength by the dust in the Martian atmosphere.		As shown by the images transmitted by the various probes and rovers, the sky is caramel colored most of the time. At sunrise and sunset, the sky can be blue near the horizon, as per the Spirit photograph. This is due to sun scattering of other wavelength by the dust in the Martian atmosphere.

	The Martian [[atmosphere]] does not filter sunlight as efficiently as on Earth, ~~leaving too much~~ UV ray and high energy particles to reach the surface. Life directly on the Martian surface is considered unlikely without additional shielding against UVs and [[cosmic radiation]] from the solar winds. An [[Early warning system for solar radiation\|early warning system]]) may be useful for an eventual settlement.		The Martian [[atmosphere]] does not filter sunlight as efficiently as on Earth, letting more UV ray and high energy particles reach the surface. Life directly on the Martian surface is considered unlikely without additional shielding against UVs and [[cosmic radiation]] from the solar winds. An [[Early warning system for solar radiation\|early warning system]]) may be useful for an eventual settlement.

	The amount of usable energy on the surface is much lower than the solar constant due to the rotation of the planet and is also reduced the ~~furter~~ away you are from the equator due to the incident angle of the light at the surface. Reflection and absorption ([[albedo]]) in the atmosphere must be considered. On Earth, the annual usable energy per m<sup>2</sup> is about 1000 kWh/y in Middle Europe and 2400 kWh/y in the Sahara.		The amount of usable energy on the surface is much lower than the solar constant due to the rotation of the planet and is also reduced the further away you are from the equator due to the incident angle of the light at the surface. Reflection and absorption ([[albedo]]) in the atmosphere must be considered. On Earth, the annual usable energy per m<sup>2</sup> is about 1000 kWh/y in Middle Europe and 2400 kWh/y in the Sahara.

	Due to the dust, sunlight on Mars is usually fairly diffuse. It comes from many directions at once, rather than directly from the sun. Rather like an overcast day on Earth. This makes it harder to concentrate sunlight using reflectors <ref>https://ntrs.nasa.gov/api/citations/19890018252/downloads/19890018252.pdf</ref>.		Due to the dust, sunlight on Mars is usually fairly diffuse. It comes from many directions at once, rather than directly from the sun. Rather like an overcast day on Earth. This makes it harder to concentrate sunlight using reflectors <ref>https://ntrs.nasa.gov/api/citations/19890018252/downloads/19890018252.pdf</ref>.
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	Sunlight can be used for [[electricity\|power generation]] by [[solar panel]]s and for growing [[plants]] in [[greenhouse]]s. It may also be used to warm a colony, especially if the habitat has [[Smart Windows]].		Sunlight can be used for [[electricity\|power generation]] by [[solar panel]]s and for growing [[plants]] in [[greenhouse]]s. It may also be used to warm a colony, especially if the habitat has [[Smart Windows]].

	Note that the sunlight is bright enough for growing plants (~~tho~~ they may grow slower). There is enough sunlight for crops out to the asteroid belt, but at Jupiter and further from the sun, artificial lights are needed for crops.		Note that the sunlight is bright enough for growing plants (though they may grow slower). There is enough sunlight for crops out to the asteroid belt, but at Jupiter and further from the sun, artificial lights are needed for crops.

	==Facts and figures==		==Facts and figures==
Line 24:		Line 24:
	*The lower lighting levels will affect plants and reduce their agricultural yield and rate of growth.		*The lower lighting levels will affect plants and reduce their agricultural yield and rate of growth.
	*Humans can make vitamin D via [[Ultraviolet]] light in our skins. Unless there are UV lights inside the base, humans will need to take vitamin supplements.		*Humans can make vitamin D via [[Ultraviolet]] light in our skins. Unless there are UV lights inside the base, humans will need to take vitamin supplements.

			==Further research==
	*What are the psychological and physiological effects of the permanent dim light on [[human]]s, [[animals]] and plants?		*What are the psychological and physiological effects of the permanent dim light on [[human]]s, [[animals]] and plants?