what evidence do we have that the space between the stars is not totally empty?

Answer 1

Due to the finding in Einstein's theory that matter and energy are equivalent, we can in some instances think of them as the same thing. Radiation is energy. Due to missions like COBE and WMAP, the background cosmic radiation pervades everywhere in "space". Energy is everywhere, so technically, space is not a total vacuum. Now, as far as matter particles are concerned, it is estimated there is approx 1 hydrogen atom per cubic centimeter. Imagine one invisible [to the naked eye] hydrogen atom in an entire 1 liter soda bottle. So, eventhough there is only one particle in that space, the rest of the space will have some sort of energy radiation pervading it. It's not really empty at all.

Answer 2

Our Galaxy, the Milky Way, has an interstellar medium. It is a combination of gas and dust. The gas can be observed directly because it emits various spectral lines at radio frequencies. The 21 cm line of atomic hydrogen is the most pervasive. There are also lines from carbon monoxide and about 100 other molecules. The dust can be observed directly because it emits infrared radiation, and it also reddens the light of stars behind it.

If you look at the Milky Way from a dark location, you can see the interstellar medium. The Milky Way appears to have dark bands across it. These are caused by dust absorption. A hundred years ago, some scientists argued that these dark bands were simply empty places where there were no stars, but then good photographs by E. Barnard showed that the dark clouds reflected some starlight. Later, these clouds were seen to emit infrared light and radio lines, so the scientists advocating an interstellar medium won the argument.

I might add that there is also an intergalactic medium, but that's another story.

P.S. The twinkling of stars is caused by the Earth's atmosphere, not the interstellar medium. Telescopes in orbit see no twinkling.

Answer 3

There is a VERY simple answer to this simple question.

Ignore all of the high level physics answers above, if they knew anything they'd tell you that you can tell that the space between stars in not totally empty because stars "twinkle."

If you looked up at the sky and there was nothing between you and the north star, it wouldn't twinkle. Space is, for the mostpart, very very empty with absolutely nothing there. However, because of the VAST distances between our planet and other stars, the light is bound to eventually hit a cloud of dust or something en route to the earth, and this is when light is deflected slightly enough to make the resulting image twinkle by the time it reaches earth. Since planets are relatively close to us, the light reflecting from our sun off of them travels through a fraction of the space and as a result the light from our planets does not twinkle, which is an easy way to pick out planets in the night sky.

Answer 4

You have asked for evidence, and not just explanations. I submit that the solar wind's interaction with the earth's magnetic field causing the northern lights is one form of evidence. Meteors streaking through the sky are another form of evidence. And finally off the top of my head I can point to comet tails. If space was totally empty, none of these would be visible.

Answer 5

The space mustnecessarily be empty only. sinceall masses havethequality of mutual attractionand attract everything to their center , no matter inspace can be filling the gap in between any to massibe bodies as eveyth thing would be attracted by them. so the space shoud be empty only.It is only on the arth vacuum has to e protected and can exist only in closed spaces because the earth is under the pressure of the atmospheric gases-(air) and they get into and forcethemselves into any tiny place that isvacant .Theyfill every space on he earth due to thier pressure andso vacuumcan not existin the open on earth.Butit canexistin space .Thre is ommeasuravble and infinite vacuum andthat is space andthesolid and gaseous matters availavble in the space shoud be justa drop in the ocean that is boundless..

Answer 6

It's not, it's full of trillions of particles broken off colliding celestial bodies. Each of these pieces of debris move very close to the speed of light and if they collide with anything they make even more super fast clumps of doom. Kessler syndrome is what comes out of too many collideing particles, and if it continues too close to the Earth, Space Travel will become impossible.

Answer 7

Motion of visible objects under gravitational influence can not be explained by the mass of the visible objects, Dark matter, as yet an undiscovered substance, must be included in our mathematical models to account for the motion.

Answer 8

The fact that we can see with telescopes things like nebulae inbetween... perhaps? ¬_¬

The fact that we can get all kinds of signals from distant stars, and they couldn't travel in a total vacuum....

Answer 9

see u are a star and me too........there is still room for discussion