Artificial sunlight?

In several experiments conducted by NASA and by the Russians plants
were grown indoors using an artificial light. What type of light was
used that produces light on the same wave lengths as the suns does?


Christopher
+++++++++++++++++++++++++
"Kites rise highest against
the wind - not with it."
Winston Churchill

(Christopher) wrote in message ...
In several experiments conducted by NASA and by the Russians plants
were grown indoors using an artificial light. What type of light was
used that produces light on the same wave lengths as the suns does?

Are you sure the lights produced the same wave length as the sun?

On TV documentaries, various forms of fluorescent lights seem to be
the popular light sources for hydroponics experiments. AFAIK, those
tend to be UV-heavy and a bit 'bluish' compared to natural sunlight.

Mike Miller wrote:
(Christopher) wrote in message ...
In several experiments conducted by NASA and by the Russians plants
were grown indoors using an artificial light. What type of light was
used that produces light on the same wave lengths as the suns does?

Are you sure the lights produced the same wave length as the sun?

On TV documentaries, various forms of fluorescent lights seem to be
the popular light sources for hydroponics experiments. AFAIK, those
tend to be UV-heavy and a bit 'bluish' compared to natural sunlight.

there are also high pressure sodiums and others. there may well be a
section in your local garden store stocking 'growlights'. plants do
not make use of all spectrum of sun, so using something that imitated
sun wold be wasteful. much better to give plants the spectrum where
they would use 95%+ of it.

--
Sander

+++ Out of cheese error +++

Mike Miller wrote:
(Christopher) wrote in message ...
In several experiments conducted by NASA and by the Russians plants
were grown indoors using an artificial light. What type of light was
used that produces light on the same wave lengths as the suns does?

Are you sure the lights produced the same wave length as the sun?

On TV documentaries, various forms of fluorescent lights seem to be
the popular light sources for hydroponics experiments. AFAIK, those
tend to be UV-heavy and a bit 'bluish' compared to natural sunlight.

there are also high pressure sodiums and others. there may well be a
section in your local garden store stocking 'growlights'. plants do
not make use of all spectrum of sun, so using something that imitated
sun wold be wasteful. much better to give plants the spectrum where
they would use 95%+ of it.

--
Sander

+++ Out of cheese error +++

(Christopher) wrote in message ...
In several experiments conducted by NASA and by the Russians plants
were grown indoors using an artificial light. What type of light was
used that produces light on the same wave lengths as the suns does?

Are you sure the lights produced the same wave length as the sun?

On TV documentaries, various forms of fluorescent lights seem to be
the popular light sources for hydroponics experiments. AFAIK, those
tend to be UV-heavy and a bit 'bluish' compared to natural sunlight.

Christopher wrote:
In several experiments conducted by NASA and by the Russians plants
were grown indoors using an artificial light. What type of light was
used that produces light on the same wave lengths as the suns does?

Standard lights used for lighting homes/offices/stadia work just fine.
The basic problem is that they emit relatively little light.

Sunlight is around a kilowatt a square meter (in most latitudes).
One 12W compact fluorescent light generates as much light as a window
around 5-6cm square.
I'm currently growing some water plants under 2*12W CF lights, probably
producing around 2000 lumens.
Over maybe .1 square meter, for around a sixth of sunlights intensity.

However, plants generally don't exploit all sunlight.
From my (sparse) knowledge of biology, photosynthesis tops out at some
fraction of the brightest sunlight.

Christopher wrote:
In several experiments conducted by NASA and by the Russians plants
were grown indoors using an artificial light. What type of light was
used that produces light on the same wave lengths as the suns does?

Standard lights used for lighting homes/offices/stadia work just fine.
The basic problem is that they emit relatively little light.

Sunlight is around a kilowatt a square meter (in most latitudes).
One 12W compact fluorescent light generates as much light as a window
around 5-6cm square.
I'm currently growing some water plants under 2*12W CF lights, probably
producing around 2000 lumens.
Over maybe .1 square meter, for around a sixth of sunlights intensity.

However, plants generally don't exploit all sunlight.
From my (sparse) knowledge of biology, photosynthesis tops out at some
fraction of the brightest sunlight.