What-If 0047: "Alien Astronomers"

What if there was a forum for discussing these?

Moderators: Moderators General, Prelates, Magistrates

User avatar
J L
Posts: 242
Joined: Mon Jan 25, 2010 11:03 am UTC
Location: Germany
Contact:

What-If 0047: "Alien Astronomers"

Postby J L » Tue May 28, 2013 9:14 am UTC

http://what-if.xkcd.com/47/

Let's assume there's life on the the nearest habitable exoplanet and that they have technology comparable to ours. If they looked at our star right now, what would they see?
—Chuck H.

Image

I always liked William Gibson's idea (as established in Neuromancer) that maybe it won't be us who establish first contact with another world, but something or somebody else, because we're just too busy checking our digital watches ... or Twitter feeds.

Andromeda321
Posts: 123
Joined: Fri Sep 18, 2009 11:31 pm UTC

What-if 047: Alien Astronomers

Postby Andromeda321 » Tue May 28, 2013 9:16 am UTC

http://what-if.xkcd.com/47/

Let's assume there's life on the the nearest habitable exoplanet and that they have technology comparable to ours. If they looked at our star right now, what would they see?
—Chuck H.


I can't believe I'm the first, but the reason I had to post is I'm a PhD student in radio astronomy with a fun little tidbit of information with regards to the Aricebo "they'd see a big radio pulse from us" comment. You see, one of the big mysteries right now in radio astronomy is a signal observed in 2007 known as the Lorimer burst- it was basically a huge, bright burst that lasted a brief amount of time and came from outside the galaxy but was never detected again. A few have been observed in the past year (from different directions but also extragalactic), not published yet but announced at conferences, but no one has a clue what their source is just that they exist.

I have actually heard a few well-established radio astronomers say over drinks at conferences that they think it could be from an alien source, meaning they probably wouldn't say so publicly but it's fun to think about. And obviously if it was no one has a clue why they'd do it, but "a souped up Aricebo" has also been mentioned in such conversations.

Just thought some others would get a kick out of that, even if as I've said the last bit is total speculation. :)

Andromeda321
Posts: 123
Joined: Fri Sep 18, 2009 11:31 pm UTC

Re: What-If 0047: "Alien Astronomers"

Postby Andromeda321 » Tue May 28, 2013 9:17 am UTC

Drat, I got scooped! Oh well, here's my thoughts reposted from the thread I created...

I'm a PhD student in radio astronomy with a fun little tidbit of information with regards to the Aricebo "they'd see a big radio pulse from us" comment. You see, one of the big mysteries right now in radio astronomy is a signal observed in 2007 known as the Lorimer burst- it was basically a huge, bright burst that lasted a brief amount of time and came from outside the galaxy but was never detected again. A few have been observed in the past year (from different directions but also extragalactic), not published yet but announced at conferences, but no one has a clue what their source is just that they exist.

I have actually heard a few well-established radio astronomers say over drinks at conferences that they think it could be from an alien source, meaning they probably wouldn't say so publicly but it's fun to think about. And obviously if it was no one has a clue why they'd do it, but "a souped up Aricebo" has also been mentioned in such conversations.

Just thought some others would get a kick out of that, even if as I've said the last bit is total speculation. :)

User avatar
J L
Posts: 242
Joined: Mon Jan 25, 2010 11:03 am UTC
Location: Germany
Contact:

Re: What-If 0047: "Alien Astronomers"

Postby J L » Tue May 28, 2013 9:24 am UTC

Sorry for that :) I had a hard time believing I was the first, too, and couldn't resist :)

Your contribution however is much more interesting than mine. It's nice to hear there are still plenty of mysteries out there. The conferences I visit (PhD in English literature) aren't half as exciting :)

edit: Don't forget your link: Lorimer burst

User avatar
rhomboidal
Posts: 746
Joined: Wed Jun 15, 2011 5:25 pm UTC
Contact:

Re: What-If 0047: "Alien Astronomers"

Postby rhomboidal » Tue May 28, 2013 9:32 am UTC

Sad to think that aliens can't pick up our TV signals just as we develop 3-D HD. Though, even sadder to think that I can't...

rmsgrey
Posts: 2954
Joined: Wed Nov 16, 2011 6:35 pm UTC

Re: What-If 0047: "Alien Astronomers"

Postby rmsgrey » Tue May 28, 2013 11:25 am UTC

Andromeda321 wrote:Drat, I got scooped! Oh well, here's my thoughts reposted from the thread I created...

I'm a PhD student in radio astronomy with a fun little tidbit of information with regards to the Aricebo "they'd see a big radio pulse from us" comment. You see, one of the big mysteries right now in radio astronomy is a signal observed in 2007 known as the Lorimer burst- it was basically a huge, bright burst that lasted a brief amount of time and came from outside the galaxy but was never detected again. A few have been observed in the past year (from different directions but also extragalactic), not published yet but announced at conferences, but no one has a clue what their source is just that they exist.

I have actually heard a few well-established radio astronomers say over drinks at conferences that they think it could be from an alien source, meaning they probably wouldn't say so publicly but it's fun to think about. And obviously if it was no one has a clue why they'd do it, but "a souped up Aricebo" has also been mentioned in such conversations.

Just thought some others would get a kick out of that, even if as I've said the last bit is total speculation. :)


I think it was in the Rama sequels where a sizeable nuke was detonated on the far side of the sun, and the reflected signal was used to map the Solar System - the solar system's biggest radar ping...

Of course, that wouldn't be visible outside our galaxy, but still...

Andromeda321
Posts: 123
Joined: Fri Sep 18, 2009 11:31 pm UTC

Re: What-If 0047: "Alien Astronomers"

Postby Andromeda321 » Tue May 28, 2013 11:36 am UTC

rmsgrey wrote:
Andromeda321 wrote:Drat, I got scooped! Oh well, here's my thoughts reposted from the thread I created...

I'm a PhD student in radio astronomy with a fun little tidbit of information with regards to the Aricebo "they'd see a big radio pulse from us" comment. You see, one of the big mysteries right now in radio astronomy is a signal observed in 2007 known as the Lorimer burst- it was basically a huge, bright burst that lasted a brief amount of time and came from outside the galaxy but was never detected again. A few have been observed in the past year (from different directions but also extragalactic), not published yet but announced at conferences, but no one has a clue what their source is just that they exist.

I have actually heard a few well-established radio astronomers say over drinks at conferences that they think it could be from an alien source, meaning they probably wouldn't say so publicly but it's fun to think about. And obviously if it was no one has a clue why they'd do it, but "a souped up Aricebo" has also been mentioned in such conversations.

Just thought some others would get a kick out of that, even if as I've said the last bit is total speculation. :)


I think it was in the Rama sequels where a sizeable nuke was detonated on the far side of the sun, and the reflected signal was used to map the Solar System - the solar system's biggest radar ping...

Of course, that wouldn't be visible outside our galaxy, but still...


That was a lesser-known novel IRC, "The Hammer of God." I don't know if I should be impressed or depressed at knowing that piece of information.

User avatar
eran_rathan
Mostly Wrong
Posts: 1666
Joined: Fri Apr 09, 2010 2:36 pm UTC
Location: everywhere, including space.

Re: What-If 0047: "Alien Astronomers"

Postby eran_rathan » Tue May 28, 2013 11:46 am UTC

Those are just the deceleration flashes from someone's warp drive.
"Trying to build a proper foundation for knowledge is blippery."
"Squirrels are crazy enough to be test pilots."
"Google tells me you are not unique. You are, however, wrong."
rawr!

User avatar
EpicanicusStrikes
Random Boners = True Attraction
Posts: 130
Joined: Wed Nov 16, 2011 11:36 am UTC

Re: What-if 047: Alien Astronomers

Postby EpicanicusStrikes » Tue May 28, 2013 12:12 pm UTC

Man. Couldn't you have found a better link for info on the Lorimer Burst? Maybe one that didn't try to sell me a pizza cutter shaped like the Enterprise and lacked the phrase 'cosmic car crash'?

User avatar
Diadem
Posts: 5620
Joined: Wed Jun 11, 2008 11:03 am UTC
Location: The Netherlands

Re: What-if 047: Alien Astronomers

Postby Diadem » Tue May 28, 2013 12:19 pm UTC

So 'what if' has progressed from destroying the earth to destroying alien planets?

I'm not sure if I should be scared or excited :)
It's one of those irregular verbs, isn't it? I have an independent mind, you are an eccentric, he is round the twist
- Bernard Woolley in Yes, Prime Minister

User avatar
cellocgw
Posts: 1687
Joined: Sat Jun 21, 2008 7:40 pm UTC

Re: What-If 0047: "Alien Astronomers"

Postby cellocgw » Tue May 28, 2013 12:51 pm UTC

But, hey, what if (no hyphen, so I'm not violating copyright :mrgreen: ) that exoplanet's population of molpys can detect single photons in the VHF broadcast frequency range? What then?

BTW, I really liked The Sparrow as Alien Encounter stories go.
https://app.box.com/witthoftresume
Former OTTer
Vote cellocgw for President 2020. #ScienceintheWhiteHouse http://cellocgw.wordpress.com
"The Planck length is 3.81779e-33 picas." -- keithl
" Earth weighs almost exactly π milliJupiters" -- what-if #146, note 7

richP
Posts: 151
Joined: Wed Aug 17, 2011 3:28 pm UTC

Re: What-If 0047: "Alien Astronomers"

Postby richP » Tue May 28, 2013 2:17 pm UTC

regarding Twitter as a modern take on the DEW line, didn't the first public mention of the Bin-Laden raid come from some Pakistani guy tweeting about the helicopters thundering over his house?

snoopy369
Posts: 11
Joined: Mon Apr 18, 2011 9:03 pm UTC

Re: What-If 0047: "Alien Astronomers"

Postby snoopy369 » Tue May 28, 2013 2:19 pm UTC

Hmm, a slight variation of a question I sent in just after http://xkcd.com/1212/ - essentially asking what these aliens would actually receive, given the likely dispersal of the radio signal (and my inability to get a decent signal on the much-closer Earth). I wonder whether the actual questions he answers are exact questions, or if when he gets a bunch (like he must have with this, as it's an obvious and interesting question to ask) he just conflates them into one question?

cellocgw wrote:But, hey, what if (no hyphen, so I'm not violating copyright :mrgreen: ) that exoplanet's population of molpys can detect single photons in the VHF broadcast frequency range? What then?

BTW, I really liked The Sparrow as Alien Encounter stories go.


Second time I've seen that mentioned in a couple of weeks. Guess it's time for a reread. Loved the original, the sequel was not quite as good but definitely worth reading (Children of God).

Daggertrout
Posts: 9
Joined: Wed Oct 28, 2009 3:01 pm UTC

Re: What-If 0047: "Alien Astronomers"

Postby Daggertrout » Tue May 28, 2013 2:44 pm UTC

I'm lucky if I can get a cell phone signal in my kitchen. Doubt the Vulcans are watching Dr. Phil.

rmsgrey
Posts: 2954
Joined: Wed Nov 16, 2011 6:35 pm UTC

Re: What-If 0047: "Alien Astronomers"

Postby rmsgrey » Tue May 28, 2013 3:07 pm UTC

Andromeda321 wrote:
rmsgrey wrote:I think it was in the Rama sequels where a sizeable nuke was detonated on the far side of the sun, and the reflected signal was used to map the Solar System - the solar system's biggest radar ping...

Of course, that wouldn't be visible outside our galaxy, but still...


That was a lesser-known novel IRC, "The Hammer of God." I don't know if I should be impressed or depressed at knowing that piece of information.


It's possible it came up in both - Clarke wasn't shy about reusing his good ideas.

Роберт
Posts: 4285
Joined: Wed May 14, 2008 1:56 am UTC

Re: What-If 0047: "Alien Astronomers"

Postby Роберт » Tue May 28, 2013 3:49 pm UTC

One of my favorite parts:
This is more promising. The Sun is really bright[citation needed] and its light illuminates the Earth.[citation needed]
The Great Hippo wrote:[T]he way we treat suspected terrorists genuinely terrifies me.

User avatar
Klear
Posts: 1965
Joined: Sun Jun 13, 2010 8:43 am UTC
Location: Prague

Re: What-If 0047: "Alien Astronomers"

Postby Klear » Tue May 28, 2013 4:49 pm UTC

Роберт wrote:One of my favorite parts:
This is more promising. The Sun is really bright[citation needed] and its light illuminates the Earth.[citation needed]


Did you click the links? That's my favourite part of it.
Last edited by Klear on Tue May 28, 2013 4:50 pm UTC, edited 1 time in total.

MongoTheGeek
Posts: 4
Joined: Fri Feb 03, 2012 3:38 am UTC

Re: What-If 0047: "Alien Astronomers"

Postby MongoTheGeek » Tue May 28, 2013 4:50 pm UTC

I have often wondered how much of our power grid seems out into the infinite. North America is a huge antenna broadcasting at 60Hz. Europe is pinging away at 50Hz.

User avatar
tibfulv
Posts: 48
Joined: Tue Nov 27, 2012 11:31 am UTC

Re: What-If 0047: "Alien Astronomers"

Postby tibfulv » Tue May 28, 2013 5:21 pm UTC

Klear wrote:
Роберт wrote:One of my favorite parts:
This is more promising. The Sun is really bright[citation needed] and its light illuminates the Earth.[citation needed]


Did you click the links? That's my favourite part of it.


I think Randall is hinting that he wants us to buy him a new car. Or a new horse.

speising
Posts: 1922
Joined: Mon Sep 03, 2012 4:54 pm UTC
Location: wien

Re: What-If 0047: "Alien Astronomers"

Postby speising » Tue May 28, 2013 5:32 pm UTC

Klear wrote:
Роберт wrote:One of my favorite parts:
This is more promising. The Sun is really bright[citation needed] and its light illuminates the Earth.[citation needed]


Did you click the links? That's my favourite part of it.


what kind of link is site:craigslist.org+chevrolet+citation supposed to be?

User avatar
Klear
Posts: 1965
Joined: Sun Jun 13, 2010 8:43 am UTC
Location: Prague

Re: What-If 0047: "Alien Astronomers"

Postby Klear » Tue May 28, 2013 5:40 pm UTC

speising wrote:
Klear wrote:
Роберт wrote:One of my favorite parts:
This is more promising. The Sun is really bright[citation needed] and its light illuminates the Earth.[citation needed]


Did you click the links? That's my favourite part of it.


what kind of link is site:craigslist.org+chevrolet+citation supposed to be?


Dunno, but it doesn't work in chrome. I just did a search for chevrolet+citation.

User avatar
candybrie4zo
Posts: 15
Joined: Wed Oct 03, 2012 7:00 pm UTC
Location: Maryland

Re: What-If 0047: "Alien Astronomers"

Postby candybrie4zo » Tue May 28, 2013 6:17 pm UTC

speising wrote:
Klear wrote:
Роберт wrote:One of my favorite parts:
This is more promising. The Sun is really bright[citation needed] and its light illuminates the Earth.[citation needed]


Did you click the links? That's my favourite part of it.


what kind of link is site:craigslist.org+chevrolet+citation supposed to be?


It's a formatted Google search(or maybe any search engine, I'm not sure on that). Its supposed to search the site craigslist.org for things to do with chevrolet and citation.

User avatar
eran_rathan
Mostly Wrong
Posts: 1666
Joined: Fri Apr 09, 2010 2:36 pm UTC
Location: everywhere, including space.

Re: What-If 0047: "Alien Astronomers"

Postby eran_rathan » Tue May 28, 2013 7:14 pm UTC

Image
[citation needed]
"Trying to build a proper foundation for knowledge is blippery."
"Squirrels are crazy enough to be test pilots."
"Google tells me you are not unique. You are, however, wrong."
rawr!

User avatar
J L
Posts: 242
Joined: Mon Jan 25, 2010 11:03 am UTC
Location: Germany
Contact:

Re: What-If 0047: "Alien Astronomers"

Postby J L » Tue May 28, 2013 7:58 pm UTC

cellocgw wrote:BTW, I really liked The Sparrow as Alien Encounter stories go.

The Sparrow was great. I thought the build-up was a bit too long, but it really paid out in the end.

User avatar
Djehutynakht
Posts: 1546
Joined: Thu Feb 10, 2011 1:37 am UTC

Re: What-If 0047: "Alien Astronomers"

Postby Djehutynakht » Tue May 28, 2013 10:37 pm UTC

Aww.. Someone beat me to Citation Needed.

It is pretty funny.

Mikeski
Posts: 840
Joined: Sun Jan 13, 2008 7:24 am UTC
Location: Minnesota, USA

Re: What-If 0047: "Alien Astronomers"

Postby Mikeski » Wed May 29, 2013 7:37 am UTC

MongoTheGeek wrote:I have often wondered how much of our power grid seems out into the infinite. North America is a huge antenna broadcasting at 60Hz. Europe is pinging away at 50Hz.

Much like Randall's comment about TV stations not wasting power to advertise to E.T., your local power company is not paying to pump 60Hz energy into space. There's a bit of a magnetic field wrapping around power lines, of course, but no significant "broadcasting".

And if they were "broadcasting", they'd do it poorly. A good antenna is something like, say, a half-wavelength-long wire. At 50-60Hz, you've got wavelengths on the order of 5000 km. Not a lot of 2500-km-long segments on our power grids.

And if power lines were good broadcasters, the whole national grid is hardly in phase. So, individual lines would be canceling each others' signals out as often as reinforcing them, for a net effect of "not a lot".

User avatar
Steve the Pocket
Posts: 596
Joined: Mon Apr 23, 2007 4:02 am UTC
Location: Going downtuuu in a Luleelurah!

Re: What-If 0047: "Alien Astronomers"

Postby Steve the Pocket » Wed May 29, 2013 8:25 am UTC

"Earthshine" sounds like something a hippie would name their kid. Or possibly their band, if they're a bit less stupid.
cephalopod9 wrote:Only on Xkcd can you start a topic involving Hitler and people spend the better part of half a dozen pages arguing about the quality of Operating Systems.

Baige.

MongoTheGeek
Posts: 4
Joined: Fri Feb 03, 2012 3:38 am UTC

Re: What-If 0047: "Alien Astronomers"

Postby MongoTheGeek » Wed May 29, 2013 11:55 am UTC

Mikeski wrote:
MongoTheGeek wrote:I have often wondered how much of our power grid seems out into the infinite. North America is a huge antenna broadcasting at 60Hz. Europe is pinging away at 50Hz.

Much like Randall's comment about TV stations not wasting power to advertise to E.T., your local power company is not paying to pump 60Hz energy into space. There's a bit of a magnetic field wrapping around power lines, of course, but no significant "broadcasting".

And if they were "broadcasting", they'd do it poorly. A good antenna is something like, say, a half-wavelength-long wire. At 50-60Hz, you've got wavelengths on the order of 5000 km. Not a lot of 2500-km-long segments on our power grids.

And if power lines were good broadcasters, the whole national grid is hardly in phase. So, individual lines would be canceling each others' signals out as often as reinforcing them, for a net effect of "not a lot".


The US grid was the last I heard 2 grids each one in phase with itself, not necessarily with each other, bad things happen to anything out of phase when connected. The grid's themselves are over 2500 km across.

I know they aren't intentionally broadcasting but it strikes me as an awful lot of wire and power.

User avatar
eran_rathan
Mostly Wrong
Posts: 1666
Joined: Fri Apr 09, 2010 2:36 pm UTC
Location: everywhere, including space.

Re: What-If 0047: "Alien Astronomers"

Postby eran_rathan » Wed May 29, 2013 12:03 pm UTC

MongoTheGeek wrote:
Mikeski wrote:
MongoTheGeek wrote:I have often wondered how much of our power grid seems out into the infinite. North America is a huge antenna broadcasting at 60Hz. Europe is pinging away at 50Hz.

Much like Randall's comment about TV stations not wasting power to advertise to E.T., your local power company is not paying to pump 60Hz energy into space. There's a bit of a magnetic field wrapping around power lines, of course, but no significant "broadcasting".

And if they were "broadcasting", they'd do it poorly. A good antenna is something like, say, a half-wavelength-long wire. At 50-60Hz, you've got wavelengths on the order of 5000 km. Not a lot of 2500-km-long segments on our power grids.

And if power lines were good broadcasters, the whole national grid is hardly in phase. So, individual lines would be canceling each others' signals out as often as reinforcing them, for a net effect of "not a lot".


The US grid was the last I heard 2 grids each one in phase with itself, not necessarily with each other, bad things happen to anything out of phase when connected. The grid's themselves are over 2500 km across.

I know they aren't intentionally broadcasting but it strikes me as an awful lot of wire and power.


That's also completely ignoring Earth's magnetic field, which keeps probably 99% of anything that is transmitted in [citation needed].
"Trying to build a proper foundation for knowledge is blippery."
"Squirrels are crazy enough to be test pilots."
"Google tells me you are not unique. You are, however, wrong."
rawr!

User avatar
markfiend
Posts: 468
Joined: Fri Jul 06, 2007 9:59 am UTC
Location: UK (Leeds)

Re: What-If 0047: "Alien Astronomers"

Postby markfiend » Wed May 29, 2013 12:12 pm UTC

Steve the Pocket wrote:"Earthshine" sounds like something a hippie would name their kid. Or possibly their band, if they're a bit less stupid.

True fact: Gala Wright, the daughter of former Pink Floyd keyboard player Rick Wright, has the middle name "Starshine".
Attoc dna Sublab evol eht teews secoiv fo eht slrug
pronouns: he/him/his

User avatar
Pfhorrest
Posts: 3545
Joined: Fri Oct 30, 2009 6:11 am UTC
Contact:

Re: What-If 0047: "Alien Astronomers"

Postby Pfhorrest » Wed May 29, 2013 10:20 pm UTC

In high school I knew a girl named Rainbow, who had siblings named Sunshine and Moonbeam.

And my name is Forrest.

Yeah, I kinda grew up in a hippy town...
Forrest Cameranesi, Geek of All Trades
"I am Sam. Sam I am. I do not like trolls, flames, or spam."
The Codex Quaerendae (my philosophy) - The Chronicles of Quelouva (my fiction)

User avatar
eran_rathan
Mostly Wrong
Posts: 1666
Joined: Fri Apr 09, 2010 2:36 pm UTC
Location: everywhere, including space.

Re: What-If 0047: "Alien Astronomers"

Postby eran_rathan » Wed May 29, 2013 11:07 pm UTC

Pfhorrest wrote:In high school I knew a girl named Rainbow, who had siblings named Sunshine and Moonbeam.

And my name is Forrest.

Yeah, I kinda grew up in a hippy town...


One of my friends growing up was named Winter, and his sister (unremarkably) was Summer (not Glau).
"Trying to build a proper foundation for knowledge is blippery."
"Squirrels are crazy enough to be test pilots."
"Google tells me you are not unique. You are, however, wrong."
rawr!

Mikeski
Posts: 840
Joined: Sun Jan 13, 2008 7:24 am UTC
Location: Minnesota, USA

Re: What-If 0047: "Alien Astronomers"

Postby Mikeski » Thu May 30, 2013 12:23 am UTC

MongoTheGeek wrote:The grid's themselves are over 2500 km across.

But no individual wire is. You can't build antennas piecemeal like that.

Guardian of the Cloud
Posts: 2
Joined: Mon Jun 03, 2013 12:03 am UTC

Re: What-If 0047: "Alien Astronomers"

Postby Guardian of the Cloud » Mon Jun 03, 2013 12:17 am UTC

I just love the Hitchhiker's reference and citation. :D

Danno81
Posts: 17
Joined: Mon Dec 20, 2010 9:58 pm UTC

Re: What-If 0047: "Alien Astronomers"

Postby Danno81 » Tue Jun 04, 2013 9:59 am UTC

There was a 2009 April fools story about finding and recovering our own TV signals reflected back from somewhere in space. It still goes around as truth now and again:

http://www.themarysue.com/lost-doctor-w ... -in-space/

We should broadcast all TV signals into space via a huge array of space based high gain antennas aimed at various points in space just to see if any of the 'spots' are reflected back in decades to come. I think ~1,000,000 transmitters should do us for starters. Cost?!? What cost???

If Sky/NASA/ESA/Virgin/Red Bull won't do it then the Russians would, they're up for anything as long as it costs a lot and looks cool!

User avatar
AlexTheSeal
Posts: 53
Joined: Mon Oct 26, 2009 12:57 am UTC

Re: What-If 0047: "Alien Astronomers"

Postby AlexTheSeal » Wed Jun 05, 2013 6:38 pm UTC

Does this mean that the Golden Age SF story about old geezers paying for passage on the first FTL flight from Earth so that they can rewatch live broadcasts of The Howdy Doody Show from their youth won't come true after all?

Code: Select all

10 REM WORLD'S SMALLEST ADVENTURE GAME
20 PRINT "YOU ARE IN A CAVE (N, S, E, W)? ";
30 INPUT A$
40 GOTO 10

Lulled to sleep by the one-hertz chuckle of Linux logfile writes since 1997.

ijuin
Posts: 799
Joined: Fri Jan 09, 2009 6:02 pm UTC

Re: What-If 0047: "Alien Astronomers"

Postby ijuin » Wed Jun 05, 2013 6:54 pm UTC

It could work if the starship had a receiver as powerful as the Aricebo radio telescope on it.

User avatar
Copper Bezel
Posts: 2374
Joined: Wed Oct 12, 2011 6:35 am UTC
Location: Web exclusive!

Re: What-If 0047: "Alien Astronomers"

Postby Copper Bezel » Thu Jun 06, 2013 1:04 am UTC

Depending on when the story was written and set, even that wouldn't help. Arecibo is mentioned as being able to transmit more than "a few light years," but I'm assuming that that requires the receiving party to have a similarly massive space telescope to get the signal. If the signal was sent on the order of decades ago, even having Arecibo on one end doesn't seem to be enough.
So much depends upon a red wheel barrow (>= XXII) but it is not going to be installed.

she / her / her

nixiebunny
Posts: 8
Joined: Mon Apr 11, 2011 7:23 am UTC

Re: What-If 0047: "Alien Astronomers"

Postby nixiebunny » Tue Jun 25, 2013 8:52 pm UTC

That thing about the 60 Hz North American grid being a big transmitting antenna... You forget that AC power distribution is 3 phase (thank you, Tesla). The EM fields of three phases cancel each other out, so the net 60 Hz field seen from a distance is always perilously close to zero.

Citation needed. No Chevettes, please. I had one once. It was free, and still not worth it.

User avatar
keithl
Posts: 597
Joined: Mon Aug 01, 2011 3:46 pm UTC

Re: What-If 0047: "Alien Astronomers"

Postby keithl » Wed Jul 27, 2016 10:25 pm UTC

Two years later - will anyone read this?

The most luminous emissions life makes are forest fires or large grassland fires, viewed on the night side of the Earth. The spectrum of the combustion products will be unique. With a large enough telescope to resolve a planet from the Sun's disk, anomalous bright spots with the right spectra are a definite sign of combustable plant life and oxygen atmosphere. However, most natural fires are small, and spread slowly.

Pre-Columbian Native Americans (or the most commonly used term, "Indios") did not have hard metals like iron. No axes, saws, root-cutting plows. They cleared land with fire. Many cultures (like the Inca and Maya) were also astronomers, and timed their rituals to astronomical events. If fires were one of those rituals, and the priests were rigid buttheads who commanded large regions to set fires at the exact wrong time ("But your Holiness, it's way too dry out there!" "Sacrifice this heretic to the Gods!") then large multisourced fires could merge into a huge region-spanning firestorm. For a few hours, the night side of the Earth could be much brighter than the day side.

ET would have to be looking everywhere, of course, with zillions of big telescopes. Perhaps their priests command them to.

Or their fire safety bureacracies. Perhaps the aliens will land in Brazilia someday, demanding a huge fine for prehistoric fire carelessness, with huge compound interest for late payment and collection expenses.


Return to “What If?”

Who is online

Users browsing this forum: No registered users and 2 guests