Your My Hy-Vee account provides access to your history, allows you to print records, submit multiple prescriptions at once and more. Learn more. This healthy lifestyle program emphasizes eating for good health, weight loss and being physically active. Beginâ¢ is not a âdietâ- Beginâ¢ is a plan to help with lifelong wellness.
Given sufficient temperature and pressure, 4 hydrogen nuclei fuse to produce helium, at the same time giving off energy in the form of heat and light and other forms of radiation. This means that stars, with a few exceptions such as super-massive stars, last for many billions of years.
More massive stars are hotter and brighter. Massive stars have more fuel to sustain their output, but their energy output or luminosity is roughly proportional to the fourth power of their mass. A star twice as massive as the sun will emit energy 2 x 2 x 2 x 2 or 16 times the rate of the sun. With only twice as much fuel to sustain it, the star will only shine 2/16 or 1/8 as long as the sun before running out of fuel. We might compare stars to people.