"Stars can not be seen from space."
Incorrect, they can be seen from space with the naked eye and video equipment under right conditions. These conditions will be explained later in this post.
"Atmosphere or particles are needed to see light!"
... your eyes, retina and all, are particles. As is the receptors on a camera (Film or chip.) It is like shining a laser into your eye, fewer particles in the air allows for photons to fly less interupted into your eyes. If anything, that experiment mentioned with the laser means the receiving end of the laser will have more photons hitting it.
If the point made was "you can't see the laser from the side" - well yeah, that is because photons aren't bouncing out of the direct path by hitting particles, and bouncing into your eye. When you "see" the beam, you are seeing the particle "source" as the photons from the laser bounces of the things in the air.
The same is with stars, we see stars by directly observing the light. In space there are less (but still some!) particles in the way... stars will appear significantly brighter. The light is not as "focused" like a laser beam however, so - while it does "bounce sideways" like in the laser experiments with an atmosphere - it is far less intense of a stream due to the difference and distance of source material. (EG: We can see God's Rays from the side, shining down from the sky... because that is the stream of photons from the sun breaking through the clouds. If we were UNDER them, we would look up and see bright sunshine!)
In short: Light can be seen in space.
But what about stars in photos?
Take photography 101 and you will understand! It is simple mechanics. I will give you a down to earth explanation first.
Ever taken a photo out of a window during the day...from inside? You may have noticed that - even though your lights may be on in the house, it is significantly darker than outside, if not solid black.
Go to a stadium at night, stand in the middle of the field, and then try to take a photo of the trees off in the distance under a street lamp. In most cities at least, the street lamp is far far dimmer than stadium lighting. You might see a little bit of information on your photo, but not as much as if you were standing in the dark, with no stadium or stadium lighting in the way. Why is this?
Photography cameras have several mechanics. In simple wording, consider the following.
1: Bigger the lens = more light collected as a whole
2: More open the lens = more light let in as a whole (aperture)
3: Longer exposure = more light collected through time
4: More sensitive recording medium = dimmer light sources seen easily, bright light sources extremely over powering
To properly photograph stars at night, there are many techniques to be taken...but the cheapest and most efficient...and most common is the following.
First, you need a tripod with a motor on it, because the earth moves! Why is this a problem you ask? Remember number three? Long exposure! A big lens is VERY expensive (I've seen some professional ones hit $4,000 and way more!) and cumbersome... and few are built for maximum light exposure needed for stellar photography. To compensate for the lack of good/cheap lens work, photographers use exposure time to make up for this. More time exposed to light = more light collected into a single shot.
This is why a motor is needed, if you just do a "long" exposure with no motor to move the camera against the Earth's movement- then you just end up with bright lines across your photo of the night sky!
The other down-side to this? Lots of light collected over longer periods of time means bright sources of light increasingly blind your camera. A street lamp for example, would over-power and white-out your photograph of the stars if you were unwise enough to try to take long exposures of the sky under a light. Even something as simple as your cell phone's lighted screen is enough to ruin these photographs.
In space, this becomes HARDER... all our current craft orbit close to Earth. Night exposures do work - they are just not as affective/easy. Why? Because we have a giant reflective source called Earth blinding our camera to the much dimmer, and further, stars. Same for moon photos. You could get a photo of the stars, but the moon and anything near it would be a wall of white.
"Why not as many/any at all in video then?"
Video cameras work much differently. They expose on a per-frame basis. Long star shots can last 30 seconds or more. A camera takes (normally) 24 pictures a second. Most 'video' you see is lots of single shots in a row with normal photography cameras!
"My eyes?"
Eyes have a 'frames per second' as cameras, but are way more versatile and sensitive. Isn't nature great?
~8 years of photography, 3 in college. I work with video daily as well.
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