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  1. How much lux does the Sun emit? - Physics Stack Exchange

    I want to know how much lux the sun emits on a bright day - I don't mean when one stares directly at the sun, but rather when one walks casually outside when the sun is shinning brightly. Now the

  2. astronomy - How big a coincidence is the Sun and Moon having …

    May 3, 2020 · It's consensus that the very similar apparent sizes of the Moon and the Sun as seen from Earth is a coincidence (as already answered in this site). This provides us with …

  3. Nuclear fission in the Sun - Physics Stack Exchange

    The Sun's energy comes primarily from fusion of light elements in its core. It is estimated that a very small fraction of mass of the Sun (~$10^{-12}$ times the abundance of hydrogen) is …

  4. How is distance between sun and earth calculated?

    Apr 27, 2015 · Do you want to know both how the Earth-sun distance is measured and how the speed of light is measured? Those are completely different things. As I asked before, separate …

  5. What is actually meant by 'sun set' and 'sun rise' times, when …

    Feb 15, 2017 · If this is the case, then when we read things like what time sun sets and rises on websites, books, calendars, other official times, et al… does that mean when we see for …

  6. Why does Sun appear white at noon? - Physics Stack Exchange

    Sep 6, 2024 · The Sun appears white at noon because the sunlight reaching the observer maintains its full spectral composition, meaning that all visible wavelengths arrive in nearly …

  7. What is the simplest way to prove that Earth orbits the Sun?

    Apr 17, 2015 · Assume you're talking to someone ignorant of the basic facts of astronomy. How would you prove to them that Earth orbits the Sun? Similarly, how would you prove to them …

  8. Why is the Sun almost perfectly spherical? - Physics Stack Exchange

    Sep 22, 2015 · The Sun has neither of these (the centrifugal acceleration at the equator is only about 20 millionths of the surface gravity, and Jupiter is too small and too far away to have an …

  9. Why does the sun make me feel warm? - Physics Stack Exchange

    Aug 27, 2015 · The sun outputs about 1300 watts per square meter (W/m²) in space near the earth, which gets reduced to around 650 W/m² in the middle of the day after going through the …

  10. The "official" mass of the sun as unit? - Physics Stack Exchange

    There is no official "mass of the sun" in kilograms. However there is an official "solar mass parameter" $ \mathrm {GM}_\mathrm {s}$ (previously known as the heliocentric gravitation …