Naked Science Forum
Non Life Sciences => Technology => Topic started by: curioussciencer198 on 03/02/2016 02:08:30
-
As usual, Google is unhelpful. I've looked this up and i've gotten many results, some saying it's possible, some saying it's not, and some unrelated results. I came across this forum and decided that this was the most appropriate place to get my question answered. Like the title suggests, is it possible for satellites to see through your walls/roof and get a clear picture of you? If this is true, is it possible for a regular civilian to access these privileges? Like I can look up a site and there you have it.
-
Hello curioussciencer
The answer is that it depends upon what you mean by "see through". My eyes, for instance, cannot see through the walls of my house, but my mobile phone can. This is because the material from which my walls are constructed is opaque to visible light. But to longer wavelength microwaves the wall may as well not be there.
Therefore, whether a satellite can see a signal through a wall or a roof depends upon the nature of that signal. If you are talking about a satellite phone conneting with a communications satellite, then that radiation should make it through. If you are talking about a spy satellite trying to take pictures of you in your living room using normal light, that isn't possible.
-
The distortion of 100km of atmosphere is quite severe, so satellites have problems seeing anything clearly, even on a cloud-free day in brilliant sunshine. Spy satellites will be able to recognize you by the way you walk before they can recognize your facial features.
So let's ignore the $billions spent annually on advanced spy satellite technology, and look at what might be possible from a spy camera across the road.
House walls and roofs are opaque to:
- Visible light
- Ultraviolet light
- Infra-red light
- Millimeter-wavelength microwaves
- ..and the same for windows, if you draw the blinds
Radio wavelengths from the cm to hundreds of meters do make it into your home, but this wavelength is so coarse that it cannot get a clear image of a person.
X-Rays also would make it into your home, but they would go straight through, providing an image of your bones. But hopefully, spy agencies would be responsible enough not to irradiate whole houses with X-Rays! (and X-Rays can't be used from satellites.)
I think that by far the simplest way for a spy agency to see clearly inside your house would be to hide small cameras in every room. Or maybe just permanently turn on the camera and microphone on your smartphone, so they can see and hear whatever you are doing, wherever you are.
-
Far infrared satellite imagery has been used to detect buried buildings at archeological sites in Egypt. Infrared shows up different materials under the surface as they absorb different amounts of heat. The satellites can resolve about 1m so you don't see much detail just building shape, but would show which parts of your house were warmer.
-
Thank you for all the replies, everyone. However, I'd still like to make my question a bit clearer: When I mean "see through", I meant if there was a certain wave (Gamma, Infared, Thermal, etc) that had a frequency high (or low) enough to pierce through a person's house and get a clear, real time picture/video of what they're currently doing. If it is possible, could someone as simple as me, who can barely comprehend all this information, have access to these privileges and have the ability to stalk whoever I please. I'm asking this because I'm afraid that someone's doing that exact same thing to me.
-
I would guess that if your walls are invisible at a certain frequency, it is quite likely that you would be invisible at that frequency as well.
It is not entirely impossible that someone could be spying on you--there are crazy stalker-type people out there. But I think they would be more likely to use the traditional low-tech methods of peeking in your windows and digging through your trash. You can and should call the police if someone is stalking you in this manner.
You should also consider the possibility that no one is spying on you, and it's only a paranoid feeling (we all get that feeling that we are being watched sometimes--it's nothing to be ashamed of...)
-
I meant if there was a certain wave (Gamma, Infared, Thermal, etc) that had a frequency high (or low) enough to pierce through a person's house and get a clear, real time picture/video of what they're currently doing.
Here is a graph showing what frequencies can get through the atmosphere.
[ Invalid Attachment ]
The frequencies that can penetrate the atmosphere are the only frequencies available for a satellite to work with.
So looking at the graph the only frequencies out of those available that can penetrate your walls are the radio waves and as stated above they are too coarse to give real time clear pictures let alone video.
So the answer to your question is no. A satellite can not be equiped with the capability to take clear pictures or video through your walls.
Hope that helps.
-
Thank you for all the replies, everyone. However, I'd still like to make my question a bit clearer: When I mean "see through", I meant if there was a certain wave (Gamma, Infared, Thermal, etc) that had a frequency high (or low) enough to pierce through a person's house and get a clear, real time picture/video of what they're currently doing. If it is possible, could someone as simple as me, who can barely comprehend all this information, have access to these privileges and have the ability to stalk whoever I please. I'm asking this because I'm afraid that someone's doing that exact same thing to me.
ROFLMAO! NO.. not a chance. Not even the government can see what you're doing in your home from a satellite. There are some exceptions, but I'm going to go out on a limb and say that none of those exceptions would be something you ever need to worry about.
That said, if you own a smart phone, they wouldn't need a satellite.. They'd just tap into your phone and whatever your camera or microphone can pick up would be transmitted out.. Even if you turn the phone off, it can still be turned back on and you'd still think the phone is turned off. The ONLY way to prevent this is to remove the battery from the phone. Anyone notice how phones are designed these days so the batteries can't easily be removed like the old flip phones?
So, can someone spy on you in your home? Absolutely.. The phone company, and by extension, the government, can easily spy on you through a smart phone.. There is also software on the market to let your spouse or another family member do the same thing without needing the help of your phone company. I think the software is like $50 or something and it can do the exact same thing... listen through your phone even though you think its off, track your location, etc.
If you're really that worried about satellites, I've heard that wrapping tinfoil around you head can help prevent some of it.. (sorry, couldn't resist posting that information)
-
Of course it is possible. Your every movement is being recorded by the CIA, KGB, Mossad, Special Branch, Google and the Inland Revenue. Your thoughts are being read by David Cameron himself. Big Brother was 32 years ago, after all.
Quite what these agencies do with all this information is beyond me, and apparently beyond them too - why else do they keep asking for paper tax returns?
There is no hiding place.
-
Of course it is possible. Your every movement is being recorded by the CIA, KGB, Mossad, Special Branch, Google and the Inland Revenue. Your thoughts are being read by David Cameron himself. Big Brother was 32 years ago, after all.
Quite what these agencies do with all this information is beyond me, and apparently beyond them too - why else do they keep asking for paper tax returns?
There is no hiding place.
That's just cruel....Have a little mercy on the poor guy... [;D]
-
Cruel? Me? ISIL don't even bother with satellite images - they just know you are guilty.