All About the Sun! Posted on August 25, 2017 by Gavin White Share this post This week, many of us got a chance to view (through safe viewing glasses, we hope!) a solar eclipse. This rare absence of daytime light as the Moon passes over the Sun brought renewed attention to the star that always shines at the center of our solar system. On average, light travels from the sun to Earth in about 8 minutes and 19 seconds. That means that the light coming from the Sun right now probably won’t even make it to Earth by the time you finish reading this post. Fortunately, our home star has been shining for ages and will continue to shine for a long time to come (think billions of years!). That sunlight is critical to life on earth. Plants need it to create energy, which animals (including us) receive in turn by eating them. On a more basic level, the Sun keeps us warm, and its gravity holds us in orbit. Without it, Earth would be nothing but a cold dead rock floating aimlessly around the universe. Luckily, we rotate around this great ball of energy and reap its benefits. Understanding this tremendous power and how to use it is critical, especially when planning an outdoor space. For millennia great builders have planned their spaces and structures around this ever-present aspect of our environment. Below are just a few ways we try to harness the power of the Sun at GTECH: First, certain plants need a certain amount of light. For instance, most trees demand a lot of sun, and will not grow if planted in a spot that is shady for much of the day. Other plants, like ferns, can’t survive in too much sun – they need a little, for sure, but too much and they can burn and shrivel. Proper planting demands knowing where sunlight falls your site all throughout the day. Plant labels usually identify the amount of sun a plant needs to prosper as follows: Full sun – Plants need at least 6 hours of direct sun daily Part sun – Plants thrive with between 3 and 6 hours of direct sun per day Part shade – Plants require between 3 and 6 hours of sun per day, but need protection from intense mid-day sun Full shade – Plants require less than 3 hours of direct sun per day Of course, being mindful of sun exposure is important for humans, too. People appreciate shade on hot days and can get burnt if out in the sun for too long. Planting trees or building shade structures can ensure your space is a place where people want to spend time, even in the heat of summer. Sometimes we like to use simple “shade sails” to make our sites cool: Nowadays, we even have the technology to harness the Sun’s energy as electricity. And it’s quite a lot of energy to capture! The amount of solar energy that reaches the surface of the planet in one year is about twice as much as will ever be obtained from all of the Earth’s non-renewable resources of coal, oil, natural gas, and mined uranium combined. Of course, we can’t capture all of that, but we are developing increasingly efficient technologies for converting energy from the Sun into energy we can use for any number of tasks. For instance, Pitt’s School of Engineering built an array of solar panels next to our Green Playce in Homewood to power an aquaponic fish farming and food growing system in a greenhouse on site. And the greenhouse itself takes advantage of a south-facing orientation to accept and absorb more heat, keeping the space warm and comfortable for plants and people, even in winter. Thoughtful plant selection, placement of structures, and much more requires an understanding of that most constant source of energy on Earth – the Sun. Besides, none of us would be here without it. Earth really is, literally, all about the Sun. So, next time you catch a glimpse of it (remember, it’s not polite or healthy to stare) be sure to blink in thanks!