That is called epigenetics and is controlled by environmental factors such a temperature, solar radiation exposure or food or lack of food.

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Another ETF with exposure to solar is the Market Vectors Solar Energy ETF ( KWT) which counts GT Solar ( SOLR) as its largest holding at a 10.46% weighting, followed closely by First Solar at 10.09%.

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The article pointed out that with the government taking a strong stance toward solar energy, investors were investigating ways to gain exposure to the sector.

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Simultaneously, surface exposure is maximized for the installation of solar devices.

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Additionally, the solar minimum during that time will also limit the radiation exposure to the astronauts.

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Though solar companies have seen their stocks take a significant hit so far this year, with the government taking a strong stance toward solar energy, some investors are investigating ways to gain exposure to the sector.

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