Is it always Dark in space?
If you get away from city lights and look up, the sky between the stars appears very dark indeed. Above the Earth's atmosphere, outer space dims even further, fading to an inky pitch-black. And yet even there, space isn't absolutely black.
Space is full of stars, countless stars, which are all about as bright as the sun. And in an infinite eternal universe no matter what direction you picked, if you look far enough in that direction, you would see a star or galaxy.
There are no days or nights in deep space. Days and nights occur for individuals that are on the surface of or associated with a rotating planet. The side currently toward the sun is the 'day side', by definition and the opposite side is the 'night side'. This is also true for satellites rotating about the planet.
According to a new study scheduled to be published in The Astrophysical Journal, scientists have determined that outer space isn't pitch black at all — it's actually filled with light.
No, in fact light only stops when it is absorbed by an electron in an atom of an object. Light in a perfect vacuum travels on at its full speed until it hits something.
Dark energy makes up approximately 68% of the universe and appears to be associated with the vacuum in space. It is distributed evenly throughout the universe, not only in space but also in time – in other words, its effect is not diluted as the universe expands.
A succession of astronauts have described the smell as '… a rather pleasant metallic sensation ... [like] ... sweet-smelling welding fumes', 'burning metal', 'a distinct odour of ozone, an acrid smell', 'walnuts and brake pads', 'gunpowder' and even 'burnt almond cookie'.
Space emits many wavelengths of light - including a lot of blue and red light that our human eyes can see - but also ultraviolet light, gamma rays, and X-rays, which remain invisible to us.
Things in space which release or reflect light, like stars or planets, can be seen either with the naked eye or with telescopes. By looking at that light, scientists can either directly tell where objects in space are, or at least can make deductions about their locations.
The earth is rotating at a tilted axis relative to the sun, and during the summer months, the North Pole is angled towards our star. That's why, for several weeks, the sun never sets above the Arctic Circle.
Is space always silent?
Sound does not travel at all in space. The vacuum of outer space has essentially zero air. Because sound is just vibrating air, space has no air to vibrate and therefore no sound. If you are sitting in a space ship and another space ship explodes, you would hear nothing.
Although there is nothing in physics that says time must flow in a certain direction, scientists generally agree that time is a very real property of the Universe. Our science is thus based on the assumption that the laws of physics, and the passage of time, exist throughout the Universe.
No, you cannot hear any sounds in near-empty regions of space. Sound travels through the vibration of atoms and molecules in a medium (such as air or water). In space, where there is no air, sound has no way to travel.
On Earth, sound mainly travels to your ears by way of vibrating air molecules, but in near-empty regions of space there are no (or very, very few) particles to vibrate – so no sound.
Because space is a near-perfect vacuum — meaning it has exceedingly few particles — there's virtually nothing in the space between stars and planets to scatter light to our eyes. And with no light reaching the eyes, they see black.
Although our eyes cannot see all the colors in the electromagnetic spectrum, we can enjoy the colors of space.
The International Space Station travels at a brisk 17,100 miles per hour. That means it orbits Earth every 90 minutes—so it sees a sunrise every 90 minutes. Thus, every day, the residents of the ISS witness 16 sunrises and 16 sunsets.
The answer: The stars are there, they're just too faint to show up.
The ISS orbits Earth every 90 minutes. So, instead of receiving 12 hours of light followed by 12 hours of dark, astronauts experience 45 minutes of light followed by 45 minutes of dark. That's 16 sunrises and sunsets each day!
On Earth, sound travels to your ears by vibrating air molecules. In deep space, the large empty areas between stars and planets, there are no molecules to vibrate. There is no sound there.
Is there a color we Cannot see?
Red-green and yellow-blue are the so-called "forbidden colors." Composed of pairs of hues whose light frequencies automatically cancel each other out in the human eye, they're supposed to be impossible to see simultaneously.