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.
HID or High Intensity Discharge lamps are the most common type of marijuana grow lights used for indoor growing and are arguably the most efficient way of producing good yields indoors. The HID family includes, Metal Halide (MH) and High Pressure Sodium (HPS).f youâre using CFLâs as your weed grow lights, you are better using more, lower wattage bulbs to spread the light around the plant. You will need to keep CFLs close to your plant as they a have poor light brilliance. Increase your light coverage and penetration by hanging lights around the side of the plant.