Recent comments in /f/space

Ritari_Assa-arpa t1_je28wr9 wrote

Reply to Why from Earth do we see all these stars but in images taken from space we see none? by Suitable-Victory-105

When looking sky during daytime our atmosfare makes sky blue, which means there is some matter what effects way we see sky and space. When taking pics shooting parameters are adjusted to get best possible, or wanted, outcome to taken pic; ISO, shutter speed, aperture. If you take on the moon sky will appear black.

However, if you take pic about sky from moon it shouldnt matter if its moons day or night. Sun might lit whole moon, but without atmosfare there cant be same light pollution we have on earth. Same goes if you are on space walk, facing away from earth, moon and sun, there is nothing to reflect sun light since its empty vacuum. There cant be light pollution which will effect taken pic. Then it should be possible to take picture of all stars when you adjust settings right for stars and you are back against sun, earth and moon.

There is another way to think this over; when we are on earth during night we see sky as black, full of stars (depending on light pollution here on earth), but night for us, on dark side of earth, is illusion created by body of earth. Night sky we see is only partially shadowed by earth body, and space around that shadow is full of sun light, we just dont see it because there is nothing to reflect it to us.

Since earth is "round" we can play with idea we are precisely middle of the night on middle of calm pacific ocean. This means you are looking sky from surface of ball limited only horizon and you are from your point of view, middle of the night, at the "highest point' of that ball, earth precisely between you and sun. We all know how light goes straight line from sun, and night is just shadow created by body of earth, and this means sky around horizon cant be in earths shadow. Still we can see those stars. Sun doesnt wash away stars, but during night time without lit atmosfare we see clearly what space looks like.

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greatstarguy t1_je28kfp wrote

Reply to comment by maulinrouge in More Water Found on Moon, Locked in Tiny Glass Beads by LanceOhio

Imagine crushing a Snickers bar in your hand. Your body heat makes it softer, and when you squeeze it, the filling comes out.

That’s basically what they’re proposing. Heat and compress moon rocks to get the water and oxygen out of them, and you can use those for life support and the leftover slag for building things. If it’s all solar-powered, it’s a lot more convenient than other methods.

The sticking point here is how much we’ll be able to get out of these rocks, and how useful the leftover slag is.

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mmixLinus t1_je282wq wrote

Reply to Why from Earth do we see all these stars but in images taken from space we see none? by Suitable-Victory-105

Take a shoe outside during a sunny day and take a picture of it.

At night, take a picture of the Moon.

What do these images have in common? They are both of sunlight reflected once, which means they were taken using the same settings!

So anything sunlit in space is going to be so bright you will have to lower the exposure settings to not get an over-exposed image, which will also result in no stars, as they are so much weaker.

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Obvious_Cranberry607 t1_je25wqd wrote

Reply to Why from Earth do we see all these stars but in images taken from space we see none? by Suitable-Victory-105

The ones you are talking about are adjusted to properly expose an object that is brighter than the stars, which means the stars will usually be too dim to notice. If you look at some pictures of dim objects, like the Earth at night from the ISS (https://eol.jsc.nasa.gov/Videos/CrewEarthObservationsVideos/) you can definitely see the stars.

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