1420 MHz--- the emission frequency of cold hydrogen gas

In summary, Paul Davies' book The Eerie Silence discusses the SETI project and explains that scientists search for radio messages from space aliens at 1420 MHz, the emission frequency of cold hydrogen gas. This frequency is measured from the crest of an electromagnetic wave to the next crest or trough. It is caused by hydrogen's electron transitioning between two closely spaced energy states and can be absorbed from ambient radiation or collisions. When the electron falls back down to the lower energy state, it releases an EM wave. Other sources of EM radiation include accelerated electric charges and thermal radiation from hot objects.
  • #1
timmeister37
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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?
 
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  • #2
The 1420 MHz emission is caused by hydrogen's electron transitioning between two closely spaced energy states. The atom can absorb energy from ambient radiation or collisions, which can cause the electron to jump from the lower energy state to the slightly higher energy state. After a small amount of time this electron falls back down to the lower energy state, which then generates an EM wave of a frequency of 1420 MHz. You can read a much more details explanation here.

timmeister37 said:
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.

EM radiation (EM waves) are emitted from either accelerated electric charges or magnetic sources, or when atoms/molecules transition from higher energy to lower energy states. Most of the EM radiation from hot objects, such as the Sun or an incandescent light bulb, are caused by charges being accelerated as they bounce off of each other. In 'cold' gases, the frequency and energy of the collisions are relatively low, so the dominant source of radiation is from these 'electronic transitions' when electrons fall from higher to lower energy states.

timmeister37 said:
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?

It is always emitting EM radiation by virtue of being warmer than absolute zero. This is called thermal radiation and is caused by the charges bouncing around due to their thermal motion. The hotter the object, the greater the amplitude of the collisions and the greater the average frequency of the emitted radiation. This is why iron (or other objects) glow red when heated to a high temperature. At high temps the frequency of the thermal radiation finally starts to be high enough in the visible spectrum for us to see.
 
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  • #3
Excellent post, Drakkith. But I still don't fully understand this.

Drakkith said:
The 1420 MHz emission is caused by hydrogen's electron transitioning between two closely spaced energy states. The atom can absorb energy from ambient radiation or collisions, which can cause the electron to jump from the lower energy state to the slightly higher energy state.

What would a hydrogen atom collide with that would cause the hydrogen atom to absorb energy?

After a small amount of time this electron falls back down to the lower energy state, which then generates an EM wave of a frequency of 1420 MHz. You can read a much more details explanation here.

What would cause the electron to fall back down to the lower energy state after a small amount of time? Why would the electron's falling back down to a lower energy state release a wave of electromagnetic radiation?
Most of the EM radiation from hot objects, such as the Sun or an incandescent light bulb, are caused by charges being accelerated as they bounce off of each other.

What do you mean exactly when you used the word charges?
In 'cold' gases, the frequency and energy of the collisions are relatively low, so the dominant source of radiation is from these 'electronic transitions' when electrons fall from higher to lower energy states.

I still don't understand why an electron's dropping to a lower energy state causes the emission of an electromagnetic wave.
It is always emitting EM radiation by virtue of being warmer than absolute zero.

What is "it", iron?
This is called thermal radiation and is caused by the charges bouncing around due to their thermal motion. The hotter the object, the greater the amplitude of the collisions and the greater the average frequency of the emitted radiation. This is why iron (or other objects) glow red when heated to a high temperature. At high temps the frequency of the thermal radiation finally starts to be high enough in the visible spectrum for us to see.

In The Eerie Silence, Paul Davies says that cold hydrogen gas emits radiation at a frequency of 1420 Mhz. If changing the heat causes a change in radiation frequency, how would the aliens know to broadcast at 1420 Mhz to reach humans? For instance, let's say that hydrogen gas emits radiation at a frequency of 1420 Mhz at -10 degrees fahrenheit. And let's say hydrogen gas emits radiation at 1400 Mhz at -5 degrees fahrenheit. And let's say hydrogen gas emits radiation at 1380 Mhz at 2 degrees fahrenheit. How did the SETI project come to assume that the aliens would communicate with radio waves to humans at 1420 Mhz then? It sounds arbitrary. Before I created this thread, I thought that the emission frequency of 1420 Mhz for cold hydrogen gas was not arbitrary.

P.S. I looked at the link you gave me, but it kind of went over my head. From your link: "Because of the quantum properties of of radiation, hydrogen in its lower state will absorb 1420 MHz and the observation of 1420 MHz in emission implies a prior excitation to the upper state."

What will hydrogen in its lower state absorb at a frequency of 1420 MHz?
 
  • #4
timmeister37 said:
What would a hydrogen atom collide with that would cause the hydrogen atom to absorb energy?

Anything. Other atoms or molecules, photons, or even large particles of dust.

timmeister37 said:
What would cause the electron to fall back down to the lower energy state after a small amount of time? Why would the electron's falling back down to a lower energy state release a wave of electromagnetic radiation?

The drop to the lower energy state is a intrinsic, spontaneous phenomenon, meaning that it happens on its own without something else causing it. The release of an EM wave happens because the change in energy states causes a change in the EM field that propagates outward as an EM wave.

timmeister37 said:
What do you mean exactly when you used the word charges?

Electric charges. Things like protons, electrons, or ions (atoms or molecules missing electrons or with extra electrons).

timmeister37 said:
What is "it", iron?

Yes.

timmeister37 said:
In The Eerie Silence, Paul Davies says that cold hydrogen gas emits radiation at a frequency of 1420 Mhz. If changing the heat causes a change in radiation frequency, how would the aliens know to broadcast at 1420 Mhz to reach humans?

The change in temperature does not change the frequency emitted from hydrogen at 1420 MHz. This is because this particular emission is not thermal radiation, as it isn't caused by the random collisions of charged particles. Instead this particular emission is caused by the electron dropping from a higher energy state to a lower one in a single hydrogen atom. A similar phenomenon generates emission spectra in all elements, just using different starting and ending energy states. See the balmer series for another example with hydrogen.

timmeister37 said:
What will hydrogen in its lower state absorb at a frequency of 1420 MHz?

It absorbs ambient radiation at the same frequency.
 
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  • #5
Post #4 on this thread was very informative, but I don't have any further questions about post #4 at the moment.

I would like to ask about something you wrote in post #2 though.

Drakkith said:
It is always emitting EM radiation by virtue of being warmer than absolute zero. This is called thermal radiation and is caused by the charges bouncing around due to their thermal motion. The hotter the object, the greater the amplitude of the collisions and the greater the average frequency of the emitted radiation. This is why iron (or other objects) glow red when heated to a high temperature. At high temps the frequency of the thermal radiation finally starts to be high enough in the visible spectrum for us to see.

Ok, so iron is always emitting thermal radiation. But is iron also always emitting EM radiation due to the iron's electrons transitioning between two closely spaced energy states (like hydrogen always does)?
 
  • #6
timmeister37 said:
Ok, so iron is always emitting thermal radiation. But is iron also always emitting EM radiation due to the iron's electrons transitioning between two closely spaced energy states (like hydrogen always does)?

Yes, but the thermal radiation is overwhelmingly dominant.
 
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  • #7
timmeister37 said:
Ok, so iron is always emitting thermal radiation. But is iron also always emitting EM radiation due to the iron's electrons transitioning between two closely spaced energy states (like hydrogen always does)?
They actually are the same thing.

To recap what has been said in previous posts, when matter is in an excited state, it will eventually decay to the ground state by emission of a photon. For individual atoms or molecules, only certain energies are possible, so only photons of certain energies (or wavelengths or frequencies, they are related to each other for photons) can be emitted. When considering dense matter, such as a block of iron or a star, all energies are possible and photons of all energies can be emitted.

Now, how does matter get excited? Mostly by absorbing radiation (photons), by collision with other matter, or by getting energy from something hotter. So the iron bar emits because it has a temperature (it emits even at room temperature, but we don't see it since it is mostly infrared light), as all objects around you do. The higher the temperature, the more energetic the light, which is why a hot iron bar glows red or white, as does the Sun. This is because at a higher temperature, there is more energy, meaning higher excited states, meaning higher-energy photons.

Even in the deep outer space, the temperature is not absolute zero, such that cold hydrogen gas still has some energy to be in excited states. But there is so little energy that there is basically a single excited energy level hydrogen can be found in, at an energy corresponding to 1420 MHz from the ground state. This is how we can observe hydrogen all over the universe.

As for SETI, I must admit that I never understood why intelligent aliens would try to communicate precisely at that frequency.
 
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  • #8
DrClaude said:
Even in the deep outer space, the temperature is not absolute zero, such that cold hydrogen gas still has some energy to be in excited states. But there is so little energy that there is basically a single excited energy level hydrogen can be found in, at an energy corresponding to 1420 MHz from the ground state. This is how we can observe hydrogen all over the universe.

As for SETI, I must admit that I never understood why intelligent aliens would try to communicate precisely at that frequency.

The theory is that aliens would try to communicate with humans at 1420 MHz because hydrogen gas emitting EM radiation at 1420 MHz is ubiquitous throughout the universe. So 1420 MHz would recognized as a special radio frequency throughout the universe by all intelligent life.
 
  • #9
timmeister37 said:
The theory is that aliens would try to communicate with humans at 1420 MHz because hydrogen gas emitting EM radiation at 1420 MHz is ubiquitous throughout the universe. So 1420 MHz would recognized as a special radio frequency throughout the universe by all intelligent life.
I know, but I still don't get it. "We're intelligent and we want to find other intelligent life, so let's send a signal at the most common natural frequency in the universe, so other intelligent life know it is artificial."
 
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DrClaude said:
I know, but I still don't get it. "We're intelligent and we want to find other intelligent life, so let's send a signal at the most common natural frequency in the universe, so other intelligent life know it is artificial."

Any other frequency would be a shot in the dark.
 
  • #11
I'm with @DrClaude on this one. If I'm in a chorus and everyone is singing middle C, would I sing middle C in order to get heard? I think I would sing F# !
 
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  • #12
hutchphd said:
I'm with @DrClaude on this one. If I'm in a chorus and everyone is singing middle C, would I sing middle C in order to get heard? I think I would sing F# !
That's what I do! With no effort at all... :smile:
 
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  • #13
hutchphd said:
I'm with @DrClaude on this one. If I'm in a chorus and everyone is singing middle C, would I sing middle C in order to get heard? I think I would sing F# !

I've worked with a vocalist who thought that way.
 
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  • #14
DrClaude said:
That's what I do! With no effort at all... :smile:
Bad analogy. When the space aliens'radio telescopes are set for a random number, there is only an infinitesimal chance that we earthlings would be on the right frequency to detect them.

When a choir performs before a human audience right next to them, the audience can hear any human pitch singing.
 
  • #15
DrClaude said:
I know, but I still don't get it. "We're intelligent and we want to find other intelligent life, so let's send a signal at the most common natural frequency in the universe, so other intelligent life know it is artificial."

I still don't get your position. "We're intelligent and we want to find other intelligent life, so let's send a signal at some random frequency. We will use a roullette wheel to randomly pick a frequency. The aliens spin a roulette wheel which randomly lands on frequency 3169 MHz. Ok, we will broadcast at 3169 MHz and hope that some other intelligent life light years away also random selects to check for signals at 3169 MHz ."

Our number system, Arabic numerals, adds a second digit at 10. This is prolly based on the fact that a human has ten fingers. Aliens are just as likely to have 8 fingers and add a second digit at 8. So a logical round number for humans to use for radio like 1,000 is probably not going to be a round number for the aliens. The aliens might just as well have 512 as the equivalent of our 1,000.

What alternative do you have in mind if not using 1420 MHz?
 
  • #16
I like the concept of ##1420\pi MHz##. If they inhabit our dimensions surely they will know ##\pi##. And that presumably gets it out of the schmutz.
 
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hutchphd said:
I like the concept of ##1420\pi MHz##. If they inhabit our dimensions surely they will know ##\pi##. And that presumably gets it out of the schmutz.
I thought of pie before as being a natural thing to check. Pie sounds like another logical radio frequency to check in addition to 1420. So you might be on to something.

Perhaps it is difficult to send radio waves at frequency 3.14 MHz. That might make 3.14 a poor choice of frequency to search at.

Anyway, why complicate things by multiplying 1420 by 3.14?

P.S. what does schmutz mean?
 
  • #18
It is I believe from the Yiddish for something dirty or unwanted...extraneous. Someone moreconversant may correct me...
 
  • #19
hutchphd said:
It is I believe from the Yiddish for something dirty or unwanted...extraneous. Someone moreconversant may correct me...

Why complicate things by multiplying 1420 by 3.14?

Please explain.
 
  • #20
Will a lone hydrogen atom in outer space emit EM radiation at 1420 MHz if there are no other atoms around the lone hydrogen atom?
 
  • #21
It would not be "some random frequency" and I think it pretty easy to produce and "see" with small equipment. Because 1420Mhz is ubiquitous, this popped immediately into my head.
 
  • #22
timmeister37 said:
I thought of pie before as being a natural thing to check. Pie sounds like another logical radio frequency to check in addition to 1420. So you might be on to something.

Perhaps it is difficult to send radio waves at frequency 3.14 MHz. That might make 3.14 a poor choice of frequency to search at.

Anyway, why complicate things by multiplying 1420 by 3.14?
You can't use pi MHz because their units of time (and frequency) are probably different from ours (think where our "second" comes from, although it's not the modern definition of the second), so they won't recognise the number pi in the signal (or we, if it's from them, at a frequency different from pi MHz). The frequency of the hydrogen emission is a constant - the numerical value will depend on the units used, but the physical frequency is the same - and multiplying it by a recognisable constant like pi can make an intelligent signal, while distinguishing it from natural H emission.
 
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  • #23
timmeister37 said:
Will a lone hydrogen atom in outer space emit EM radiation at 1420 MHz if there are no other atoms around the lone hydrogen atom?
Can anyone answer this?
 
  • #24
timmeister37 said:
Can anyone answer this?
Yes - a lone hydrogen atom can radiate:
Its lidetime is around 10 million years. Therefore a hydrogen atom that has collided with an atom can travel a long way before radiating.
And the atom can be excited not only by colliding, but also by absorbing a photon. Which means that the atom will eventually emit a new photon, in a new direction.
 
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  • #25
snorkack said:
Yes - a lone hydrogen atom can radiate:
Its lidetime is around 10 million years. Therefore a hydrogen atom that has collided with an atom can travel a long way before radiating.

You mean that a hydrogen atom's lifetime is around 10 million years; correct? I am not an expert on chemistry. Perhaps there is a term called lidetime in chemistry that I am not aware of. That's why I have to ask.

If a hydrogen atom's lifetime is 10 years, why does that mean that a hydrogen atom that has collided with an atom can travel a long way before radiating? If a hydrogen atom collides with another atom, wouldn't the hydrogen atom start radiating electromagnetic radiation immediately (as opposed to traveling a long way before radiating)?
And the atom can be excited not only by colliding, but also by absorbing a photon. Which means that the atom will eventually emit a new photon, in a new direction.

Well, as soon as the hydrogen atom collides with another atom, isn't the hydrogen atom going to instantly be emitting a stream of photons (I'm guessing like billions and billions of photons per second)?

What do you mean , in a new direction? I thought that a hydrogen atom just radiates electromagnetic directions in all directions simultaneously.
 
  • #26
An excited atom will typically emit a single photon.
This particular transition has a very long lifetime (it is "forbidden")...I will assume @snorkack knows the numbers.
A hydrogen atom lasts much longer than 10 million years.
 
  • #27
hutchphd said:
An excited atom will typically emit a single photon.

Are you sure? Other threads that I've read about this at Physics Forums say that a hydrogen atom emits a stream of photons, which implies more than one photon.
This particular transition has a very long lifetime (it is "forbidden")...I will assume @snorkack knows the numbers.
A hydrogen atom lasts much longer than 10 million years.

What particular transition has a very long lifetime?

If a hydrogen atom lasts much longer than 10 million years, why did snorkack say a hydrogen atom's lifetime is 10 million years?
 
  • #28
timmeister37 said:
Are you sure? Other threads that I've read about this at Physics Forums say that a hydrogen atom emits a stream of photons, which implies more than one photon.
Most transitions emit a single photon at a time (with a few significant exceptions).
But the thing is that when there are several excited states, if the atom is in a higher excited state, it may decay to a lower excited state rather than ground state. In which case it must emit a photon when it decays to a lower excited state and more photon/s when the lower excited state decays, as it must.
timmeister37 said:
What particular transition has a very long lifetime?

If a hydrogen atom lasts much longer than 10 million years, why did snorkack say a hydrogen atom's lifetime is 10 million years?
The transition from the parallel-spin state to antiparallel spin state.
It is the lowest excited state of all. There are no lower intermediate excited states to decay to, and that one decay goes by emission of one photon. But it is extremely slow.
And no, the atom does not emit continuously. A tritium atom has half-life 12 years which makes "lifetime" 17 years. But it emits a beta particle in a very specific fraction of second that happens in a random time. Likewise, a protium atom in its lowest excited state has lifetime 10 million years and will emit the 21 cm radio wave at a specific but random time.
Once the protium atom is in its true ground state, it will last forever, yes. Or till it encounters something.
 
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  • #29
Good grief there is so much mis-information in this thread it is difficult to know where to start. Here's 3 corrections:
  1. SETI does not listen only on 1420 MHz, the main search covers all frequencies between 1 and 9 GHz.
  2. If you are only going to look at one frequency then 1420MHz (or more accurately 1,420,405,752.7667±0.0009 Hz) is a bad place to look, because as @hutchphd pointed out this frequency is dominated by natural transmissions.
  3. ## \pi \times 1,420,405,752.7667 \textrm {Hz} ## is a better place to look - this frequency does not depend on the use of the decimal numbering system for ## \pi ## or our definition of a second.
 
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timmeister37 said:
Are you sure? Other threads that I've read about this at Physics Forums say that a hydrogen atom emits a stream of photons, which implies more than one photon.

What they mean is that hydrogen atom emits one single photon per one single transition between states. If you are talking specifically between two states which has no intermediate states in between, then a single photon excitation to populate the higher state will lead to an emission of one single photon to come back down.

If you have thousands and millions of hydrogen atoms, and irradiate it with millions and billions of photons, then the resulting emission from hydrogen is also going to be a stream of photons. As @snorkack pointed out, if you look at other systems then there are exceptions of course, such as sequential emission of photons while relaxing to lower states, or in some very special cases literally emitting two entangled photons at the exact same time. But these cases are rather rare, and is limited to specific cases.

What particular transition has a very long lifetime?

If a hydrogen atom lasts much longer than 10 million years, why did snorkack say a hydrogen atom's lifetime is 10 million years?

"Forbidden" transitions may have very long lifetimes. As @snorkack mentioned, spin-forbidden transition (transition between different spin-multiplicity), but be sure to not confuse this term when you look it up because it usually refers to multiple electron systems.

In this particular case of hydrogen, it refers to the pair of electron (which have a spin of 1/2) and proton (which also have a spin of 1/2). The transition of 1420 MHz happens between two different spin-states (parallel or antiparallel proton electron spin) of the 1s orbital. This is because the energy arising from the proton-electron pair is lowered when the spin is antiparallel and raised when it is parallel. This also means that the 1420 MHz transition is a electron spin-"flipping" process due to the interaction with photon.

In order to actually test if "flipping" an electron spin is forbidden, you will have to do some quantum mechanics. Specifically, you will have to build spin-wavefunction for each of the ground and excited states, and multiply them in a bra-ket manner (overlap integration). The resulting value should be zero, which means that they are forbidden. But I don't think you are at a level where you can understand this. So for now, just trust us on the fact that spin-"flipping" transition is forbidden.

In general, there are other "forbidden" transition such as LaPorte (symmetry) forbidden transitions. For example, transition between 1s- and 2s-orbitals is forbidden by orbital symmetry. Other examples may be benzene and porphyrin if you look at organic molecules, but their "forbidden-ness" is mitigated by other factors (electron-phonon coupling). You can test this in a similar manner explained above, although with a position operator between bra- and ket-vector.
 
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  • #31
Why look at that frequency of 1420Mhz, it is precisely the base noise of the entire universe, and in general the intensity (the number of photons per second received) is a constant in almost all directions. Then certain patterns of increase or decrease in intensity may be due to the fact that in the observed area there is more or less hydrogen gas, this would be in galactic halos, galaxies, galaxy clusters, places where we understand life could thrive like here, not very close not too far from the center of the galaxy.
If the observation is maintained in a certain sector, as I said, we would notice that the intensity is a constant, but what happens if instead of a constant signal we receive a pattern of intensity variable?
We would first try to determine if it is a random pattern, or not, any intelligent civilization could recognize it, there will be 1000000 or more ways to generate a non-random pattern of intensities with the same frequency.
It is a mechanism similar to what AM radio tuners do, they modulate the amplitude keeping the frequency constant.
This is extremely useful for transmitting and receiving artificial signals, why? Because nature can send random or repetitive signals with a defined pattern, the pattern that is repeated, but a pattern created by an artificial intelligence will send clear signals away from repetitive patterns, but they will not be random either and whoever receives them will unequivocally know to conclude immediately that the signal is artificial.
On August 15, 1977 at 11:16 p.m., the Big Ear radio telescope received a radio signal of unknown origin for exactly 72 seconds coming from the eastern part of the constellation Sagittarius and reaching an intensity 30 times higher than the background noise. That was the WOW signal

Other reasons are the millions of possible frequencies throughout the radio-electric spectrum, but it is thought that any intelligent civilization advanced enough to study the universe should know about radio-astronomy and therefore do radio astronomical research. If this is the case, they should know the natural emission frequency of neutral hydrogen, which, being the most abundant element in the universe, provides an optimal channel for the emission and reception of signals.
So 1420Mhz stands out in particular for its ability to concentrate large amount of power in the lowest bandwidth. This is the so-called continuous wave that, because it is of a fixed and stable frequency, is the optimal wave to bridge large interstellar distances while being able to be heard at very low signal levels.
The task of deciphering what the non-random code says is another matter.
 

1. What is the significance of 1420 MHz in relation to cold hydrogen gas?

The emission frequency of 1420 MHz is significant because it is the frequency at which cold hydrogen gas emits radiation. This radiation is known as the 21-centimeter line and is a key tool for studying the distribution and properties of hydrogen gas in the universe.

2. How is the 1420 MHz emission frequency of cold hydrogen gas detected?

The 1420 MHz emission frequency of cold hydrogen gas is detected using radio telescopes. These telescopes are designed to pick up radio waves, including the 21-centimeter line emitted by cold hydrogen gas. The telescopes then convert these radio waves into signals that can be analyzed and studied by scientists.

3. Can the 1420 MHz emission frequency be used to study other elements besides hydrogen?

Yes, the 1420 MHz emission frequency can be used to study other elements besides hydrogen. However, it is primarily used to study hydrogen gas because it is the most abundant element in the universe and emits radiation at this frequency. Other elements may also emit radiation at this frequency, but it is not as common or significant as with hydrogen.

4. How does the 1420 MHz emission frequency of cold hydrogen gas help us understand the universe?

The 1420 MHz emission frequency of cold hydrogen gas is a vital tool for understanding the structure and evolution of the universe. By studying the distribution and properties of hydrogen gas, scientists can gain insights into the formation of galaxies, the expansion of the universe, and the presence of dark matter.

5. Are there any practical applications for the 1420 MHz emission frequency of cold hydrogen gas?

While the 1420 MHz emission frequency of cold hydrogen gas is primarily used for scientific research, there are some practical applications as well. For example, it is used in radio astronomy to study the universe, and it is also used in satellite communications to transmit signals back to Earth. Additionally, the technology used to detect and analyze this frequency has also led to advancements in other fields, such as wireless communication technology.

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