A vacuum is empty space. There are no molecules of air or anything else in a vacuum. Like all forms of electromagnetic waves,
light can travel through empty space, as well as through matter
.
Why is space dark?
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. —What color is the sunset on other planets?
How far does light travel in empty space?
The speed of light traveling through a vacuum is exactly
299,792,458 meters (983,571,056 feet) per second
. That’s about 186,282 miles per second — a universal constant known in equations as “c,” or light speed.
Does light disappear?
Light is made up of particles called photons that travel like waves. Unless they interact with other particles (objects), there is nothing to stop them. Unlike some types of particles,
they do not decay
, meaning that they do not spontaneously turn into other types of particles.
How fast is the speed of dark?
Darkness travels at the speed of light
. More accurately, darkness does not exist by itself as a unique physical entity, but is simply the absence of light. Any time you block out most of the light – for instance, by cupping your hands together – you get darkness.
Why can’t you go faster than the speed of light?
So
the faster something travels, the more massive it gets, and the more time slows – until you finally reach the speed of light, at which point time stops altogether
. And if time stops, well then, so does speed. And so nothing can travel faster than the speed of light.
Is time travelling possible?
In Summary:
Yes, time travel is indeed a real thing
. But it’s not quite what you’ve probably seen in the movies. Under certain conditions, it is possible to experience time passing at a different rate than 1 second per second.
Why can’t you see the sun in space?
In space or on the Moon
there is no atmosphere to scatter light
. The light from the sun travels a straight line without scattering and all the colors stay together. Looking toward the sun we thus see a brilliant white light while looking away we would see only the darkness of empty space.
How cold is space?
Hot things move quickly, cold things very slowly. If atoms come to a complete stop, they are at absolute zero. Space is just above that,
at an average temperature of 2.7 Kelvin (about minus 455 degrees Fahrenheit)
.
Will a dead body decompose in space?
Halting decomposition
And bacteria from the gut would still devour the soft tissues
. But these bacteria need oxygen to function properly and so limited supplies of air would significantly slow down the process.
Can light be destroyed?
6.
Photons are easily created and destroyed
. Unlike matter, all sorts of things can make or destroy photons. If you’re reading this on a computer screen, the backlight is making photons that travel to your eye, where they are absorbed—and destroyed.
Can light be stopped?
Physicists have been able to stop something that has the greatest possible speed and that never really stops: light
. A decade ago, physicists stopped it very for a short moment. In recent years, this extended towards stop times of a few seconds for simple light pulses in extremely cold gases and special crystals.
Is light always moving?
Light, no matter how high-or-low in energy,
always moves at the speed of light
, so long as it’s traveling through the vacuum of empty space. Nothing you do to your own motion or to the light’s motion will change that speed.
Can anything move faster than the speed of light?
Albert Einstein’s special theory of relativity famously dictates that
no known object can travel faster than the speed of light in vacuum
, which is 299,792 km/s. This speed limit makes it unlikely that humans will ever be able to send spacecraft to explore beyond our local area of the Milky Way.
What is darkness made of?
Most scientists think that dark matter is composed of
non-baryonic matter
. The lead candidate, WIMPS (weakly interacting massive particles), are believed to have ten to a hundred times the mass of a proton, but their weak interactions with “normal” matter make them difficult to detect.
Is light stronger than darkness?
Yes, there is darkness encircling us. There is an abundance of struggle, pain, and suffering. But there is also light, and
light will always be stronger than darkness
. We are light.
Can a human travel at the speed of light?
Can we travel at the speed of light?
No, we cannot travel at the speed of light
. You see, if an object travels at the speed of light, its mass will increase exponentially!
Is a black hole faster than light?
To escape from within a black hole requires faster than light speeds
, but according to Einstein’s theory of gravity, General Relativity, gravity is the distortion of space and time caused by the presence of mass.
Can a human spacecraft ever travel at the speed of light?
In 1947 humans first surpassed the (much slower) speed of sound, paving the way for the commercial Concorde jet and other supersonic aircraft. So will it ever be possible for us to travel at light speed? Based on our current understanding of physics and the limits of the natural world,
the answer, sadly, is no
.
Does the past still exist?
In short, space-time would contain the entire history of reality, with each past, present or future event occupying a clearly determined place in it, from the very beginning and for ever.
The past would therefore still exist, just as the future already exists, but somewhere other than where we are now present.
Can a wormhole exist?
Einstein’s theory of general relativity mathematically predicts the existence of wormholes, but
none have been discovered to date
. A negative mass wormhole might be spotted by the way its gravity affects light that passes by.
Where does space end?
It extends
about 20 miles (32 kilometers) above the Earth
. Floating around the atmosphere is a mixture of molecules – tiny bits of air so small you take in billions of them every time you breathe.
How do female astronauts deal with periods in space?
A combined oral contraceptive, or the pill, used continuously (without taking a week off to induce menstrual flow)
is currently the best and safest choice for astronauts who prefer not to menstruate during missions, says Varsha Jain, a gynecologist and visiting professor at King’s College London.
Is there sound in space?
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.
What does space smell like?
Astronaut Thomas Jones said it “carries
a distinct odor of ozone, a faint acrid smell…a little like gunpowder, sulfurous
.” Tony Antonelli, another space-walker, said space “definitely has a smell that’s different than anything else.” A gentleman named Don Pettit was a bit more verbose on the topic: “Each time, when I …
