- #1
timmeister37
- 124
- 25
I recently finished reading Paul Davies book The Eerie Silence, which is a book about the SETI (Search for ExtraTerrestrial Intelligence) project. In The Eerie Silence, Davies says that scientists using radio telescopes to search for radio messages from space aliens set their radio telescopes to search for messages at 1420 MHz because 1420 MHz is the emission frequency of cold hydrogen gas.
I googled this and researched this a little bit both on this message board and on other places on the internet before I created this thread.
It is my understanding that cold hydrogen gas emits electromagnetic waves ( a stream of photons) at 1420 MHz.
It is my understanding that 1420 MHz is the frequency (a unit of time) at which cold hydrogen gas emits electromagnetic waves. The frequency is probably measured from the crest of an electromagnetic wave to the next crest or the trough of an electromagnetic wave to the next trough.
Here is what I don't understand: Why does cold hydrogen gas emit electromagnetic waves at all?
Before I read Davies book, I would have assumed that only sources of light such as the sun (or a light bulb) and sources of sound such as satellite dishes and/or radio antennas emit electromagnetic waves.
Do all gases emit electromagnetic waves?
It is my understanding that all atoms can be transformed to a gas if they get hot enough. So if I heated, say, iron hot enough to make iron into a gas, would the iron emit electromagnetic waves?
I googled this and researched this a little bit both on this message board and on other places on the internet before I created this thread.
It is my understanding that cold hydrogen gas emits electromagnetic waves ( a stream of photons) at 1420 MHz.
It is my understanding that 1420 MHz is the frequency (a unit of time) at which cold hydrogen gas emits electromagnetic waves. The frequency is probably measured from the crest of an electromagnetic wave to the next crest or the trough of an electromagnetic wave to the next trough.
Here is what I don't understand: Why does cold hydrogen gas emit electromagnetic waves at all?
Before I read Davies book, I would have assumed that only sources of light such as the sun (or a light bulb) and sources of sound such as satellite dishes and/or radio antennas emit electromagnetic waves.
Do all gases emit electromagnetic waves?
It is my understanding that all atoms can be transformed to a gas if they get hot enough. So if I heated, say, iron hot enough to make iron into a gas, would the iron emit electromagnetic waves?