[yairdoza (OP)]

Recently I read that there might be up to 14 solar systems in our galaxy that are made out of anti-matter.

If any of these solar systems have technological advanced civilisation, that communicate with electromagnetic waves - could we intercept their communication and respond?

Does the fact that they are made out of anti-matter effect the electromagnetic communication.

Thanks for reading.

[Origin]

Recently I read that there might be up to 14 solar systems in our galaxy that are made out of anti-matter.

The more likely number is zero.

If any of these solar systems have technological advanced civilisation, that communicate with electromagnetic waves - could we intercept their communication and respond?

In theory there should be no problem, but I would not recommend visiting their planet or them visiting our planet and shaking their hands would be a right bad idea.

Does the fact that they are made out of anti-matter effect the electromagnetic communication.

It shouldn't since photons are their own antiparticle, so photons can be generated from matter or antimatter.

[CliffordK]

The more likely number is zero.

I agree,it is unlikely that we'll have them in this Galaxy, but perhaps there could be relatively isolated entire galaxies somewhere.  Even something like Cosmic Rays would be incredibly damaging to an antimatter cluster.

In theory there should be no problem, but I would not recommend visiting their planet or them visiting our planet and shaking their hands would be a right bad idea.

If one could reach an Antimatter rogue planet, solar system, galaxy, etc...  it would put our space system ahead a thousand years. 

It is hard to imagine any commodity that would drive trade between solar systems, but if there was, it would be matter/anti matter trade.

Just imagine the value of say a ton of anti-mercury or anti-iron. 

And an anti-matter system would be equally happy to receive "normal" matter in trade.

[Bored chemist]

Just imagine the value of say a ton of anti-mercury or anti-iron. 

And an anti-matter system would be equally happy to receive "normal" matter in trade.

So, ignoring the shipping costs*, the value of a ton of anti iron would be the same as a ton of iron.
Because, as a trader, I could simply offer to swap matter for their antimatter.
Similarly, from their point of view, they could trade a ton of scrap metal for a ton of antimatter.

* Yeah... right...

[wolfekeeper]

I think antimatter might be worth the hassle, boy or boy would it be a powerful rocket fuel!

A lump of anti-iron would be amazing. You could hold it with maglev and just ablate some off with a plasma when you want some energy.

[Bored chemist]

And, if it ever went wrong, you would never know about it.

[wolfekeeper]

Dunno actually, you could afford to put quite a lot of shielding between you and the antimatter.

Antimatter isn't quite as powerful as normally thought anyway. The matter+antimatter = complete annihilation + energy trope only applies to electrons and positrons.

[evan_au]

there might be up to 14 solar systems in our galaxy that are made out of anti-matter.

Stars (and their planetary systems) form out of dense, cold clouds of gas and dust.
- If that cloud was partly matter and partly anti-matter, it would not be cold!
- If the cloud were antimatter, and nearby stars were matter, there would be a furious reaction where the stellar wind hit the edge of the gas cloud.

Similarly, galaxies form out of multiple clouds of dust, each traveling in different directions.
- If some clouds wer matter, and some antimatter, there would be a furious reaction.

For these reasons, it is unlikely that antimatter stars could form and persist in a matter-dominated galaxy.

[Eternal Student]

Hi.
I've got to agree with evan_au.
But I'd be interested in knowing where you (yairdoza) got the original information -

Recently I read that there might be up to 14 solar systems in our galaxy that are made out of anti-matter.

  Any chance of finding out where you read that?  Does it start with   Wik  and end with  edia ?

[Halc]

Hi.
I've got to agree with evan_au.
But I'd be interested in knowing where you (yairdoza) got the original information -

Recently I read that there might be up to 14 solar systems in our galaxy that are made out of anti-matter.

www.sciencenews.org/article/antimatter-stars-antistars-milky-way-galaxy-space-astronomy

I found copies of this article on many websites, so no idea on which it might first have appeared.
They're apparently detecting 14 places where the sort of gamma radiation that Evan mentions is observed.

[Bored chemist]

Antimatter isn't quite as powerful as normally thought anyway. The matter+antimatter = complete annihilation + energy trope only applies to electrons and positrons.

What do you get from "the bigger stuff"?
On a related note, is the neutron its own antiparticle or does "spin" spoil things?

[Colin2B]

If any of these solar systems have technological advanced civilisation, that communicate with electromagnetic waves - could we intercept their communication and respond?

Does the fact that they are made out of anti-matter effect the electromagnetic communication.

It has been possible to create anti-hydrogen atoms so there is some confidence that it is possible to create larger atoms and maybe molecules. However, there are subtle differences between matter and antimatter interactions around what are known as CP violations and these are being investigated. These violations may be the reason why there is less antimatter than matter in the universe.

However, let’s look at your question which appears to have been ignored.
If it is possible to create stable complex molecules from antimatter then it is possible that it might behave in a similar way to matter and hence the construction of an antimatter radio would be possible. The photon is it’s own antiparticle and it’s unlikely that em radiation would be any different in a region containing antimatter, so I would guess that we would be able to communicate with them by radio. Understanding is a whole new ball park 

[evan_au]

is the neutron its own antiparticle or does "spin" spoil things?

A neutron consists of 1 up quark (charge: +2/3) and two down quarks (charge: -1/3 each). Total charge: 0.

An anti-neutron consists of 1 up anti-quark (charge: -2/3) and two down anti-quarks (charge: +1/3 each). Total charge: 0.
- Or should that be "anti-up quark", which would be different from a "down quark"?

Whatever you call it, an anti-neutron is different from a neutron, and the two will annihilate on contact.
- It's the quarks that spoil things...

See: https://en.wikipedia.org/wiki/Neutron

[wolfekeeper]

Antimatter isn't quite as powerful as normally thought anyway. The matter+antimatter = complete annihilation + energy trope only applies to electrons and positrons.

What do you get from "the bigger stuff"?

Electron/positrons annihilate and produce only photons, but that's not generally true:

https://en.wikipedia.org/wiki/Annihilation#Proton%E2%80%93antiproton_annihilation

[CliffordK]

If there was an antimatter star or small cluster in our galaxy with an advanced civilization, then it is quite possible they've already discovered how to capture and harness the energy of matter.

However, there would be advantages of working with an anti-civilization. 

So, for example, one could design an antimatter injector that could be made entirely out of antimatter, and construction of the antimatter component would be easy on the antimatter planet.  One could presumably even have antimatter computers and robots.

So, for example pressurized liquefied anti-Xenon gas in an anti-Iron based cylinder. The anti-Xenon could be released in a fine stream using a valve controlled by an external magnetic field.  The anti-Iron cylinder could be in a vacuum and magnetic containment.

Diamagnetic liquids would also be unique for containment, but anything with a relatively high vapor pressure under high vacuum would need a secondary antimatter containment.

[Eternal Student]

They're apparently detecting 14 places where the sort of gamma radiation that Evan mentions is observed.

Recently I read that there might be up to 14 solar systems in our galaxy that are made out of antimatter.

Thanks for the link Halc.  Here it is again in case anyone new joins the thread:
www.sciencenews.org/article/antimatter-stars-antistars-milky-way-galaxy-space-astronomy
   
  Well, I'm speechless about this.  It just seems so unlikely.  I'm sorry if I doubted your information, yairdoza.
There have been other equally remarkable discoveries and experimental results that end up disappearing quietly and I'm suspicious this will be another one of them.  Let's stay calm, it will turn out to be just some other interesting source of gamma bursts and/or experimental error.  But.... maybe.

[bearnard1212]

As far as I know, we don`t have such technology that can allow us getting in touch with some forms of life out of the Solar system. Also, we cannot travel in other galaxies or make uncrewed missions. I`ve read recently that scientists had cought a radio wave somewhere out of our Solar system

[CliffordK]

As far as I know, we don`t have such technology that can allow us getting in touch with some forms of life out of the Solar system. Also, we cannot travel in other galaxies or make uncrewed missions. I`ve read recently that scientists had cought a radio wave somewhere out of our Solar system

It isn't that we couldn't communicate or find a way to communicate, but we are limited by current radio/light/laser types of communication which would be limited to the speed of light.  So, to Proxima Centauri it would take about 4 years each way (8 or 9 years RT).  Across the Milkyway could be 100 years each way, or 200 years RT.

We are certainly able to communicate with Voyager 1 & 2 at about 17½ light hours away.  Obviously not even a light day yet.  I do wonder if we could discern a weak radio signal near a star, but one could put a relay in the outer solar system to improve transmission spacial resolution.  There have also been proposals to put radio telescopes and perhaps optical telescopes on the dark side of the moon to avoid Earth's radio and light contamination.

And, obviously choose frequencies without other cosmic contamination.

The linguistic nightmare would be difficult to deal with.  Imagine having no vocabulary, and a century until your next question is answered.  But,we are able to decipher texts over a millennia old without a dictionary.

There may well be some digital universals that might help.

So, for example, there would be only a few ways to transmit a 2 dimensional black&white bitmap photo.  And, once one got a basic B&W BMP, one could start dealing with more colors and data compression, perhaps 3rd dimensions and/or time. 

Likewise for text, we have 26 letters, plus caps, punctuation, etc.  It may well be complex to decipher, but likely the character set could be discerned with stop bits and gaps.  If one believed that one was reliably sending photos, one could do photos + captions. 

Eventually one might choose to send an entire dictionary, again accentuating characters, stops, words vs definitions, etc.

With human's limited lifetime, it would certainly be be frustrating if a child would barely get a response back from a query a lifetime ago.  I.E.  generational continuity.

Travel is far more complex as we are nowhere near the speed of light.  For many reasons one would likely choose unmanned probes or even seed ships.  We could likely develop artificial wombs inclined to do so. Of course sending life to an antimatter solar system would not be of much benefit unless they had both matter and antimatter planets, or a nearby matter star.

There would be very real issues designing equipment to last hundreds, thousands, or perhaps even tens of thousands of years without maintenance.  As well as developing longterm power sources.  One could, of course, develop a sleep mode which might help, but it might be a big gable that it would all wake back up in 10,000 years (assuming no destructive impacts). 

And, of course, sending matter to an antimatter system or visa-versa would be like sending the most powerful bomb imaginable. 

Distances beyond our galaxy are just greater, and resolution more difficult to discern.

[wolfekeeper]

If there are antimatter civilisations out there, maybe they deliver.

[CliffordK]

If there are antimatter civilisations out there, maybe they deliver.

Of course, but make sure we have a plan to receive it, and if it is 1000 years from placing the order to delivery, make sure it isn't forgotten.  A few tons of antimatter delivered at high velocity could be mighty destructive to Earth.

Perhaps it is like having a package delivery left on your neighbor's doorstep, ask for it to be delivered to Proxima Centauri where hopefully future humanity can go pick it up.