How long until the sun cannot sustain human life on earth?
The sun will last, at its current brightness for 9 billion more years. How long until the sun gets burned down to the point where it cannot sustain life on Earth anymore? Updated: I am more …
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 …
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
How is distance between sun and earth calculated?
Feb 15, 2011 · 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 …
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 …
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 …
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 …
Why does the Sun always rise in the East? - Physics Stack Exchange
Nov 26, 2014 · The Sun does not rise, it is the horizon that goes down. You say that Sun rises in the East (with a certain degree of oscillations due to the tilt of the axis) just because the Earth …
Why do we say that the Earth moves around the Sun?
3 The sun, moon, earth (and so on) all move around each other. The reason we say the earth moves around the sun is because the effects are more visible on a macro scale, and easier to …
sun - Why is sunlight spectrum continuous? - Physics Stack …
The sun's spectrum is very complex, and indeed there are a lot of "lines"—both light and dark (emission and absorption)—amidst a sea of what looks to be continuous frequencies.