Best answer gets 10 points! Please help.?

Question

Suppose two astronauts are outside the pace shuttle orbiting Earth. The audio speaker in the helmet of one astronaut quits working. The other astronaut is 1 m away and shouts a message. Can the first astronaut hear the message? Explain.

Best most thorough answer gets 10 points!

Answer 1

In order to propagate sound, you need atoms or molecules (it can be a gas , a liquid or a solid). Since your two astronauts are in vaccuum (ie nothing between them, no gas at all), they won't be able to hear each other.
The guy whose radio is not working won't even be able to read the other's lips since the glass of the helmet is tinted. So they have to come up with some sign language to communicate.

Answer 2

According to http://members.hometown.aol.com/bobalien99/moonten.htm

The Moon has no atmosphere. It is through atmosphere that light is dispersed (spread) and sound waves travel (light waves and sound waves bounce off tiny particles in a planet's atmosphere). This means that no sound can be made on the Moon. If a person spoke, he would not be heard.

So, no your astronaut would not be able to be heard.

Another interesting fact: The sky is always black because light cannot be spread, unlike on Earth where light spreads to give the sky a blue colour and on Mars where it spreads through its thin atmosphere to give the sky a pinkish/reddish colour.

Answer 3

NO. Sound waves need something to travel through. Air, water, solid. In outer space, they are in a vacuum and the sound has nothing to travel through.

BUT...
If they got close enough that their helmets were touching, it would work. The helmet to helmet contact would transmit the sound waves.

Answer 4

No.

Sound is essentially vibrations in the air, that your ear senses and your brain converts into what we understand as sound.

In space, there is no air. It is a vaccuum. Thus, like the movie Alien mentioned, no one can hear you scream in space.