What is dark matter? Dark matter is stuff in space that has gravity, but it is unlike anything scientists have ever seen before. Together, dark matter and
Dark matter is the mysterious stuff that fills the universe but no one has ever seen.
Cosmic voids (also known as dark space) are vast spaces between filaments (the largest-scale structures in the universe), which contain very few or no galaxies.
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.
The Boötes Void (/boʊˈoʊtiːz/ boh-OH-teez) (colloquially referred to as the Great Nothing) is an approximately spherical region of space found in the vicinity of the constellation Boötes, containing very few galaxies, hence its name. It is enormous, with a radius of 62 megaparsecs.
In space, no one can hear you scream. This is because there is no air in space – it is a vacuum. Sound waves cannot travel through a vacuum. 'Outer space' begins about 100 km above the Earth, where the shell of air around our planet disappears.
There's a limit to how much of the universe we can see. The observable universe is finite in that it hasn't existed forever. It extends 46 billion light years in every direction from us.
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 ...
No, there isn't sound in space.
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.
In fact, recent estimates put dark matter as five times more common than regular matter in our universe. But because dark matter does not interact electromagnetically, we can't touch it, see it, or manipulate it using conventional means.
Space is not empty. A point in outer space is filled with gas, dust, a wind of charged particles from the stars, light from stars, cosmic rays, radiation left over from the Big Bang, gravity, electric and magnetic fields, and neutrinos from nuclear reactions.
The trite answer is that both space and time were created at the big bang about 14 billion years ago, so there is nothing beyond the universe. However, much of the universe exists beyond the observable universe, which is maybe about 90 billion light years across.
The Darkest Part of the Universe--Boötes Void
Located around 700 million light-years from Earth, the Boötes void was first discovered by American Astronomer Robert Kirshner alongside with his University of Michigan colleagues back in 1981, during a survey of galaxy redshifts.
If we add up all the light coming from galaxies (and the stars within them), and from all the clouds of gas and dust in the Universe, we'd end up with a colour very close to white, but actually a little bit 'beige'.
Deep in the centre of the planet is the 'inner core', which we think is made of solid iron and nickel. This is surrounded by the 'outer core', which is also made of iron and nickel, but is molten. Convection currents in the outer core create Earth's magnetic field.
Far outside our solar system and out past the distant reaches of our galaxy—in the vast nothingness of space—the distance between gas and dust particles grows, limiting their ability to transfer heat. Temperatures in these vacuous regions can plummet to about -455 degrees Fahrenheit (2.7 kelvin). Are you shivering yet?
We can't smell space directly, because our noses don't work in a vacuum. But astronauts aboard the ISS have reported that they notice a metallic aroma – like the smell of welding fumes – on the surface of their spacesuits once the airlock has re-pressurised.
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.
The bottom line: the temperature outer space is brutally cold. The gas particles may be moving really fast, having been energized by the sun, but the outer space is huge and gas particles and stars are lightyears away from one another.
A clock in outer space moves more quickly than a clock on Earth. Heavy things like planets create a gravitational field that slows down time nearby. An example of gravity causing time dilation is that if an object is near a black hole its time will slow relative to that of time on earth.
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.
90 seconds after exposure, you'll die from asphyxiation. It's also very cold in space. You'll eventually freeze solid. Depending on where you are in space, this will take 12-26 hours, but if you're close to a star, you'll be burnt to a crisp instead.
Edwin Hubble changed the way we thought of the Universe forever.
Scientists can't directly observe black holes with telescopes that detect x-rays, light, or other forms of electromagnetic radiation. We can, however, infer the presence of black holes and study them by detecting their effect on other matter nearby.
The answer: The stars are there, they're just too faint to show up. I can illustrate with an example from everyday life. I'm sure that everyone reading this article has made the mistake of shooting a photo of a loved one standing in front of a brightly lit window.