
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 …
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
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 …
Why does the Sun "shine brighter" some days? [duplicate]
1) The sun seems brighter (more dazzling) if there is more scattering in the atmosphere. The sun would actually look very small to us in the sky if there were no atmosphere (it's the same …
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 …
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 …
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 …
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.
How hot can metal get in sunlight? - Physics Stack Exchange
May 31, 2015 · I will make some 5mm blackened steel letters for a building. Now, in the sunlight in summer, how hot can they get? EDIT: i want to place some LEDs on the back of the letters. …
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 …