Is space a true vacuum

Answer 1

Space is a vacuum because there is extraordinarily little matter there.

Gravity is the large scale organizer of matter in the universe. It is gravity that causes material objects to attract each other, and gravity "gathers" matter together to make stars and even galaxies themselves. Because gravimetric centers -- black holes, stars, planets, comets or asteroids -- attract other matter, the matter tends to "clump" around other matter. When this matter is gaseous, and it "clumps" around bodies large enough to hold it, you have an atmosphere.

The wide volume of space between planets, or between star systems, or even between the galaxies is therefore fairly free of matter. This is as little as a handful of hydrogen atoms per cubic meter of space, compared to 1024 atoms, a trillion trillion, in a cubic meter of the air we breathe. However, space is readily and regularly traversed by moving particles, from cosmic rays (ionized atomic nuclei) to the incredibly numerous but nearly-massless particles known as neutrinos.

(Due to the energy release from stars, and the interaction of its released particles, some molecules achieve escape velocity and are "lost to space" from planets. This creates an expanded exosphere in their orbits. However, at a distance from the planets, the mass content dwindles to nearly zero.)

Answer 2

Space is a vacuum because there is extraordinarily little matter there.

Gravity is the large scale organizer of matter in the universe. It is gravity that causes material objects to attract each other, and gravity "gathers" matter together to make stars and even galaxies themselves. Because gravimetric centers -- black holes, stars, planets, comets or asteroids -- attract other matter, the matter tends to "clump" around other matter. When this matter is gaseous, and it "clumps" around bodies large enough to hold it, you have an atmosphere.

The wide volume of space between planets, or between star systems, or even between the galaxies is therefore fairly free of matter. This is as little as a handful of hydrogen atoms per cubic meter of space, compared to 1024 atoms, a trillion trillion, in a cubic meter of the air we breathe. However, space is readily and regularly traversed by moving particles, from cosmic rays (ionized atomic nuclei) to the incredibly numerous but nearly-massless particles known as neutrinos.

(Due to the energy release from stars, and the interaction of its released particles, some molecules achieve escape velocity and are "lost to space" from planets. This creates an expanded exosphere in their orbits. However, at a distance from the planets, the mass content dwindles to nearly zero.)

Answer 3

"Vacuum" is not at all a good analogy. Vacua are very weak, and they really are not even a 'force'. On the earth's surface, a vacuum seems to pull things in only because there is an atmosphere around it pushing things in. The force of a vacuum is really nothing more than the force of the surrounding atmosphere, and once an equilibrium is reached, a vacuum can do nothing more. Read about atmospheric pressure to learn more. On the other hand, black holes are the sources of immensely strong gravity fields. The more mass to a black hole, the more gravity, apparently without limit.

Answer 4

By "total vacuum" do you mean completely devoid of ANYTHING? Well then no it isn't. Apart from that then yes it is a vacuum to the extent that there is no air, no pressurised gaseous elements in general and pretty much the definition of a vacuum, no atmospheric pressure. Most gases would condense then freeze when exposed to a harsh -270°C (approximate general temperature) of space but not all gases would freeze or condense to liquid. Even so the gas would be dispersed to the extent that it wouldn't be significant. A vacuum is essentially an area where there is no matter at all, no solids, liquids or gases but as i mentioned there are still 'things' present like light and subatomic particles of all kinds.

In the void between planets and stars there is 'something', whether it's sub atomic particles (for example neutrinos) or radiation (including light).

I don't think it's possible to have a complete, utter and total area that is completely and totally devoid of EVERYTHING including light, energy and sub atomic particles, not to mention dark matter and dark energy that is currently undetectable. Maybe they occur in space, maybe somewhere in a black hole they occur, i have no idea really.

It does make me wonder what a complete, utter and totally empty area of space would mean. No matter, no energy, no sub atomic particles, nothing, at all, maybe that's what s beyond space, no time either.

I had a look and there is something called a "Quantum Vacuum" that is probably the closest thing i could find that would describe a complete, total vacuum. According to Wikipedia; even then it can't be completely empty because the walls of the vacuum will produce light in the form of thermal radiation and this creates "radiation pressure". It states that even in space it isn't possible because the "Cosmic Microwave Background" fills the entire universe with this "thermal radiation". As you can tell i am no physicist and certainly have almost zero understanding of quantum mechanics which is where it gets really mind boggling. Never the less, again according to Wikipedia, a complete perfect vacuum can't exist because particles appear and disappear out of existence everywhere in the universe.

Answer 5

Yes interstellar space is a vacuum but not entirely so; at its sparsest it is about a hundred thousand billion billion (10^23) times less dense than air, so for most intents it could be treated as a vacuum. A careful examination yields extremely small amounts of gas, dust, cosmic rays (high energy particles) and so forth.. about 98 percent of which is hydrogen and helium.

Answer 6

It follows 'Gas Laws' so it's pressure is so low we call it a vacuum, it's temperature is low as well. To follow the law it's volume has to change so it is sucked into our universe as dark matter and out thro an effect we call gravity and so cycles.

Answer 7

no it has a small amount of hydrogen believed to be left over from the big bang

Answer 8

Most of it is. Amoungst all of space just about 1% of it is an actual gas, the rest is a vacuum.