The first step in measuring the distance between the Earth and the Sun is to measure the distance between Earth and another planet in terms of the distance between Earth and the Sun. So, let us assume that the distance between Earth and the Sun is a.Now, let us consider the orbit of Venus.To first approximation, the orbits of Earth and Venus are perfect circles around the Sun. Take a look at the diagram below (not to scale).nyway, the relevant numbers are: Earth-Sun distance, d = roughly 150 million km (defined as 1 Astronomical Unit). Radius of the Sun, R sun = roughly 700,000 km. Orbital speed of Earth, v = roughly 30 km/s. References: 1  Great Moments in the History of Solar Physics 1.
Marijuana Lighting, Marijuana Grow Lights and Lamps. To grow the indoor marijuana plants is to learn the right types of lighting systems. There are three types of systems of lighting that are excellent ones for the cannabis plants, these are: the incandescent, fluorescent, and the high intensity discharge.
In the old days growing marijuana under fluorescent (CFL) grow lights was pretty useless as they had low output for a large size. However, the new CFL (compact fluorescent lights) grow lights that between them cover the full visible light spectrum have made them a viable alternative.ED grow lights run on around 50% of the electricity when compared to the same HPS grow light so a 500 Watt (true draw) LED grow light will offer better output in terms of yield than a 1000 Watt HPS unit.