SFGirl
Scribus Administratus
Global user
Registered: 01-2004
Location: Nova Scotia, Canada
Posts: 939
|
|
Reply | Quote
|
|
Question for the group mind
What sort of technology could be used to image the interior of a planet or asteroid? For instance, to find something that might be buried (deep) beneath the surface?
Feel free to extrapolate wildly from current tech if necessary. Time frame would be 100 years or less from now.
Ideas?
Sherry
---
Reading: Something Rotten by Jasper Fforde
Writing: short story: Of Snow-Jewelled Hills and Ice
|
|
2/28/2005, 10:18 pm
|
Send Email to SFGirl
Send PM to SFGirl
|
Firlefanz
Master Scribe
Global user (premium)
Registered: 05-2003
Location: Germany
Posts: 502
|
|
Reply | Quote
|
|
Re: Question for the group mind
A technology that's widely in use now is seismic - you set off an explosion somehere and "listen" to how the shockwaves travel through the ground. This method has its limit at the molten core of Earth, though.
I'm not sure what else can work - sound or shock waves are fine for "dirt", but they require a set of "microphones", and a thump. And of course they are not exactly future tech.
--- - Firlefanz
Reading: "Verkaufende auf Risa" by Gundhild Dreher
Finished: "The Cloth-Merchant's Daughter", 2nd Lar Elien book
My board - Schreiberlinge unter sich |
|
3/1/2005, 3:52 am
|
Send Email to Firlefanz
Send PM to Firlefanz
|
David Meadows
Junior Scribe
Global user
Registered: 09-2003
Posts: 165
|
|
Reply | Quote
|
|
Re: Question for the group mind
Seismic sounds like the best choice to me. You could postulate more futuristic methods (measuring neutrino absorbtion, MRI or PET on a massive scale, etc) but why bother when there is tried-and-trusted "real" technology that will do the job?
---
"A room without books is as a body without a soul" -- Cicero
|
|
3/1/2005, 7:03 am
|
Send Email to David Meadows
Send PM to David Meadows
|
Uncle Mac
Master Scribe
Global user
Registered: 01-2005
Location: Steger, IL. USA
Posts: 272
|
|
Reply | Quote
|
|
Re: Question for the group mind
Seismic Sensors are correct. NASA has used them on a number of occassions. A good example would be the lunar landings of the 60's. During a few of these missions (well, at least one), the astronauts set up sensors on the surface during the ground ops portion of the mission.
Once the recovery vehicle docked with the mothership, the module was launched back at the surface of the moon and the seismic sensors in place recorded the interior composition of the moon when the recovery module hit the surface.
I would imagine that futuristic sensors would be based on a similar principle and use a combination of seismic sensors and sonar.
---
Jay M. Hurd
Author - Ascension: Book One of The Alliance Chronicles
ISBN# 1-4137-3709-9
http://ascension.pfrpg.org
Working on: Avenging Angel & The Migichinan Sourcebook
|
|
3/1/2005, 9:00 am
|
Send Email to Uncle Mac
Send PM to Uncle Mac
Blog
|
SFGirl
Scribus Administratus
Global user
Registered: 01-2004
Location: Nova Scotia, Canada
Posts: 939
|
|
Reply | Quote
|
|
Re: Question for the group mind
Hmmmm...what would you choose if you were trying to uncover information about a huge, mysterious underground artifact that you did not want to risk damaging? Setting off explosions seems like it might not be the best idea. What about a kind of ultrasound? Would that work?
And is it terribly lazy of me to ask here first instead of going off and digging up my own research? 
Sherry
---
Reading: Something Rotten by Jasper Fforde
Writing: short story: Of Snow-Jewelled Hills and Ice
|
|
3/1/2005, 9:17 am
|
Send Email to SFGirl
Send PM to SFGirl
|
Uncle Mac
Master Scribe
Global user
Registered: 01-2005
Location: Steger, IL. USA
Posts: 272
|
|
Reply | Quote
|
|
Re: Question for the group mind
To my knowledge, ultrasounds only work on liquid based obects that are solid to semi-solid (such as a pregnant female). To the limit of my understanding, explosive tests accompanied by seismopgraphic readings are the only way to go. I'll look into this some more and post my findings. It's pretty slow here at work, so I'll have some time to search.
---
Jay M. Hurd
Author - Ascension: Book One of The Alliance Chronicles
ISBN# 1-4137-3709-9
http://ascension.pfrpg.org
Working on: Avenging Angel & The Migichinan Sourcebook
|
|
3/1/2005, 10:49 am
|
Send Email to Uncle Mac
Send PM to Uncle Mac
Blog
|
Uncle Mac
Master Scribe
Global user
Registered: 01-2005
Location: Steger, IL. USA
Posts: 272
|
|
Reply | Quote
|
|
Re: Question for the group mind
Here are some sites to check out:
Pulse Radar Detection (civil engineering)
http://www.ndt.net/article/ndtce03/papers/v076/v076.htm
X-Rays from satellites
http://www.jewishmonmouth.org/content_display.html?ArticleID=93665
This one deals with using radio signals
http://pwnhc.learnnet.nt.ca/exhibits/kuukpak/discovery2.html
Ground Penetrating Radar (GPR)
http://www.cpeo.org/techtree/ttdescript/gpr.htm
Most of the non-destructive methods I'm seeing deal with the location of objects that are buried at a shallow depth (utility cables, buried 'treasure' and such).
What you will probably want to do is select the one that seems closest to your needs and scale it up to meet your needs. The last link involving GPR only goes to a depth of 15 meters (49.21245 ft) and may not suit your needs on an 'off-the-shelf' basis, but were you to scale up the device (for example a large truck or even from a spaceship with a powerful sensor array ala Star Trek), then you may not have too much of a problem detecting your buried object.
---
Jay M. Hurd
Author - Ascension: Book One of The Alliance Chronicles
ISBN# 1-4137-3709-9
http://ascension.pfrpg.org
Working on: Avenging Angel & The Migichinan Sourcebook
|
|
3/1/2005, 11:02 am
|
Send Email to Uncle Mac
Send PM to Uncle Mac
Blog
|
David Meadows
Junior Scribe
Global user
Registered: 09-2003
Posts: 165
|
|
Reply | Quote
|
|
Re: Question for the group mind
Sherry, you don't have to worry about damaging the object. Seismic waves can travel around the world. You can detonate an explosion -- not even a very big one -- thousands of miles away and pick up the reflections.
And that's today. Extrapolate that into the future and add improved detectors and supercomputers to do the analysis. You could probably have an astronaut stamp his foot on one side of an asteroid and pinpoint him from the other side!
Actually, all seismic waves consist of is... sound! They are simply pressure waves through rock. So it's not essentially different from ultrasound, just at a much lower frequency (infrasound?). I believe that Jay is right and ultrasound works better through liquids. Different frequencies propagate through different mediums differently, and it just so happens that seismic waves go through rock really well.
Picture resolution is also a matter of wavelength. So ultrasound gives excellent resolution of internal organs whereas infrasound, being much longer wavelength, probably wouldn't. But if you're trying to see gross structure in rock layers (or huge artifacts), the resolution of infrasound should be sufficient.
Disclaimer: it's been 20 years since my university geology course, so my grasp of the details may be a little hazy 
---
"A room without books is as a body without a soul" -- Cicero
|
|
3/1/2005, 11:16 am
|
Send Email to David Meadows
Send PM to David Meadows
|
SFGirl
Scribus Administratus
Global user
Registered: 01-2004
Location: Nova Scotia, Canada
Posts: 939
|
|
Reply | Quote
|
|
Re: Question for the group mind
Thanks, everyone! You were all a great help, as usual.
Sherry
---
Reading: Something Rotten by Jasper Fforde
Writing: short story: Of Snow-Jewelled Hills and Ice
|
|
3/4/2005, 4:39 pm
|
Send Email to SFGirl
Send PM to SFGirl
|
wanda7
Master Scribe
Global user
Registered: 02-2005
Location: Pacific Northwest
Posts: 312
|
|
Reply | Quote
|
|
Re: Question for the group mind
quote:
Uncle Mac wrote:
To my knowledge, ultrasounds only work on liquid based obects that are solid to semi-solid (such as a pregnant female).
The effectiveness of ultrasound depends on the density and flexibility of the material. Most of our bodies allow sound to travel at 1540 m/s. Tissue actually ranges from approximately 1440 m/s to 1640 m/s. Bone has a higher propagation speed than most tissues. Lungs are filled with gas which has a lower propagation speed. Ultrasound does not work well for looking into bone, and since the earth is likely fairly dense, compared to even bone, the propagation speed would be even higher, restricting it's usefulness. There's a whole bunch of stuff, too, about distance and ultrasound. In scanning people, ultrasound usually maxes out at 10 inches.
wanda
can you guess what i do for a living?
and, i wish it were a slow day here... i have this great idea i want to explore
---
Reading: On Equilibrium (John Ralston Saul), Saving Fish From Drowning (Amy Tan)
Writing: Three Bags Full and various short stories
Living life large, loving with compassion
|
|
3/9/2005, 5:24 pm
|
Send Email to wanda7
Send PM to wanda7
|
Add a reply
Link to us
- Blogs
- Hall of Honour
- Chat
|
You are not logged in (login)
Board's time is: 11/27/2009, 10:11 am
|
|
|
