View unanswered posts | View active topics

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 1 post ] 
Search for:
Author Message
PostPosted: Tue Nov 06, 2018 3:04 pm 
Offline
Hall of Famer
User avatar

Joined: Tue Nov 04, 2008 11:30 am
Posts: 14077
Location: The Bear Nebula
so ... scientists are apparently now eager to get this whole "are their aliens out there?" question answered

the plan seems to be to shoot lasers into space as a way to attract alien explorers

Astronomers suggest shooting a laser into space to attract aliens to Earth like a ‘porch light’

Quote:
Science fiction has taught us for decades that when alien arrive on Earth, it’s going to be a bad day for mankind. Those fictional horror stories haven’t deterred some scientists from thinking up ways that we might attract alien civilizations to Earth, and a new feasibility study suggests that we could send a laser beam into the cosmos to act like a beacon for alien life to find.

The work, which was published in The Astrophysical Journal, suggests that existing technology could be used to produce an infrared beam bright enough to be spotted by intelligent alien civilizations. Once discovered, it would be like a bread crumb trail pointing right back to Earth, and extraterrestrials could come calling.

“This would be a challenging project but not an impossible one,” James Clark, author of the study, said in a statement. “The kinds of lasers and telescopes that are being built today can produce a detectable signal, so that an astronomer could take one look at our star and immediately see something unusual about its spectrum. I don’t know if intelligent creatures around the sun would be their first guess, but it would certainly attract further attention.”

The biggest challenge in creating a beacon that could be spotted by alien is making it bold enough to be spotted from a long distance, even with the Sun doing its best to outshine it. The paper explains that a 1- to 2-megawatt laser could be sufficient if it were shot through a telescope as large as 45 meters.



Scientists Want to Use Lasers to Guide Aliens to Earth. What Could Go Wrong??

Quote:
We could build a laser that could send signals to extraterrestrial intelligence.

Not we as in the staff of Live Science. (That's probably beyond our skill set.) But we as in humanity. A new paper published yesterday (Nov. 5) in The Astrophysical Journal has found that humanity could feasibly build an infrared laser hot and bright enough that — if we shined it directly at nearby exoplanets — alien astronomers should be able to detect it using sky-watching technology not too much more advanced than our own. (Presuming they're out there, of course.) [9 Strange, Scientific Excuses for Why We Haven't Found Alien Life Yet]

It would have to be pretty huge, but not unthinkably so: One possible design the researchers proposed would require a 1 to 2 megawatt laser and at least a 100-foot (30 meter) diameter primary mirror.

It's not clear if aliens would immediately recognize the laser as a signal from intelligent life-forms, James Clark, a graduate student at MIT and the lead author on the paper, said in a statement. But, he added, "it would certainly attract attention."

The main challenge for building an alien laser beacon, the authors wrote in the paper, is that Earth isn't alone in space. Instead, it's a relatively minor one of eight planets orbiting a star far brighter than any laser humanity could reasonably hope to produce. From the perspective of an alien astronomer hundreds of light years away, the entirety of human civilization and any infrared source it might produce would be drowned out by the gigantic, white-hot source of light in our local space.

The goal of the laser then, wouldn't be to create a blinking beacon in the darkness for aliens to sit up and notice. Instead, the authors explained, it would be to make our sun look weird enough from an alien perspective to take a second look.



Aliens Might Notice Us if We Shot a Giant Laser at Them, Study Says

Quote:
Scientists have detected many exoplanets that could host liquid water—the key ingredient for life as we know it. But let’s say our wildest hopes (or worst nightmares) are true, and there are alien lifeforms inhabiting nearby worlds. How would we contact them across distances of several light years?

One way to get the attention of local ETs is to shoot a giant laser at them, according to a study published Monday in The Astrophysical Journal and authored by James Clark, a graduate student at MIT’s department of aeronautics and astronautics, along with MIT professor Kerri Cahoy.

The idea is to amplify an infrared laser signal using a giant telescope. This could produce a signal that would outshine the Sun’s infrared emissions tenfold, an anomaly that would stand out to a smart species observing our solar system from a distant exoplanet.

“This would be a challenging project but not an impossible one,” Clark said in a statement. “The kinds of lasers and telescopes that are being built today can produce a detectable signal, so that an astronomer could take one look at our star and immediately see something unusual about its spectrum. I don’t know if intelligent creatures around the Sun would be their first guess, but it would certainly attract further attention.”

The paper combines two emerging technologies—megawatt lasers and colossal telescopes. Lasers capable of megawatt blasts are in development at the Pentagon, while the 39-meter-wide Extremely Large Telescope (ELT) is currently being constructed in Chile, and is on track to become operational in 2024.

Clark and Cahoy calculated that amplifying a two-megawatt laser through the mirror of a 30-meter telescope could produce an infrared signal that would be detectable on Proxima b, a planet 4.2 light years away. A one-megawatt laser amplified by a 45-meter telescope could be spotted by any observant aliens on the seven Earth-scale worlds of the TRAPPIST-1 system, 40 light years away, according to the paper.



well, this could be interesting

if nothing else, it should provide a sci-fi writer some material for a new series

_________________
"Don't sweat the petty things and don't pet the sweaty things."
George Carlin

Image
BLOG : Emissions from the Bears Nebula


Top
 Profile  
 
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 1 post ] 

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group