Should Google earth be real time high resolution?

[John Baker]

I might not be quite accurate about the actual facts of how things are, I am basing this on what I have heard or read.

As I understand it, when GPS was first developed it was used exclusively by the government, it was hands off for the private sector. I am pretty sure the Internet was originally intended to be used by researchers and other public institutions.

The Internet has become a world wide phenomena allowing people from around the globe to interact with each other any time they want, with very little government oversight, at least here anyway, I think.

We now have satellite imagery via Google Earth of just about any place on the planet that any of us can access and use. It is especially handy for planning flights to unfamiliar airports, reconnoitering real estate, etc. The only downside to it is it is not in real time, and will only allow you to get within a thousand feet, someplace's considerably more, of the area you want to view.

I understand the government has real time satellite imagery, and that they can zoom in on just about anything, to the point of being able to read license plates from space with amazing resolution pictures.

What I am wondering is, do you think Google Earth will ever be allowed to provide the same imagery in real time to anyone who wants it? Or will it always remain in the hands of government only?

I know it would be very cool to have that capability, perhaps too cool for just anyone who wants it.

I don't know how I am advocating this concept, for or against. I know I would like to have it, though I wouldn't want my ex wife to have it. So I'm presenting it to this esteemed body of......um....well...ah....anyway, what are your thoughts?

John

 

[SkyHog]

I might not be quite accurate about the actual facts of how things are, I am basing this on what I have heard or read.

As I understand it, when GPS was first developed it was used exclusively by the government, it was hands off for the private sector. I am pretty sure the Internet was originally intended to be used by researchers and other public institutions.

The Internet has become a world wide phenomena allowing people from around the globe to interact with each other any time they want, with very little government oversight, at least here anyway, I think.

We now have satellite imagery via Google Earth of just about any place on t byhe planet that any of us can access and use. It is especially handy for planning flights to unfamiliar airports, reconnoitering real estate, etc. The only downside to it is it is not in real time, and will only allow you to get within a thousand feet, someplace's considerably more, of the area you want to view.

I understand the government has real time satellite imagery, and that they can zoom in on just about anything, to the point of being able to read license plates from space with amazing resolution pictures.

What I am wondering is, do you think Google Earth will ever be allowed to provide the same imagery in real time to anyone who wants it? Or will it always remain in the hands of government only?

I know it would be very cool to have that capability, perhaps too cool for just anyone who wants it.

I don't know how I am advocating this concept, for or against. I know I would like to have it, though I wouldn't want my ex wife to have it. So I'm presenting it to this esteemed body of......um....well...ah....anyway, what are your thoughts?

John

That technology doesn't exist for the government yet, its a conspiracy theory. But if it became available I'd support it.

 

[jesse]

The technology isn't available yet to have live on-demand images of a location at any reasonable cost. Certainly not able to just on the whim look at random things and maintain live imagery for an indefinite length of time. The physics don't allow for this.

A satalite is only going to maintain view of a certain area for a certain length of time as it passes by. There are only so many satalites. A satalite in geostaionary orbit is *WAY* out there - doubt it could get pictures of great resolution.

Much of the great Google Earth imagery was done by airplane. Not satellite.

 

[Mason]

Been watching DVD's of "24?'

 

[denverpilot]

A satellite is only going to maintain view of a certain area for a certain length of time as it passes by. There are only so many satellites. A satalite in geostaionary orbit is *WAY* out there - doubt it could get pictures of great resolution.

Some of the later Keyhole birds were similar in size to Hubble, and they were pointed down, not up. Think school-bus sized optics. Those are old enough you can read about them in books.

You're kidding yourself if you think they can't see things at great distances with clarity. It was one of these birds that could have been "tasked" with inspecting the Shuttle Columbia's *tiles* from above -- that was requested but dropped due to NASA management's overconfidence and embarrassment.

NASA Engineers don't make it a habit to ask for things they aren't sure even exist. They knew.

Not because NRO would have refused or couldn't accomplish that mission to see damage to a relatively small airframe in Low-Earth-Orbit from Geosynchronous Orbit. Techs at NASA knew they could do it.

Management wimped out. NRO might have refused for National Security reasons, but they never got formally asked.

The problem is cloud-cover when using optical systems on the planet. That and that a simple tarp can utterly defeat it once someone knows the cameras are overhead.

Thus, most of the work in the last decade has been on RADAR systems versus optics. The grants for things like the Shuttle's world-mapping RADAR missions enhanced the knowledgebase for other "assets" to be built. It wasn't *just* for raw scientific research of the planet.

Space engineers study any other folk's tech they can. It's a relatively small community. Since defense contractors don't share as much with each other as NASA can share with all of them, many Shuttle mission's data went toward learning curves for what were, at the time, future NRO assets, no doubt.

Focused long-range weak-signal RADAR technology in the RF transmission field of study, as well as digital TV "spot beams", led to advances in pinpoint long range RF reception too.

Your cell phone radiates pretty well in upward directions as it does to terrestrial towers. It's just a really damn weak signal that far up. Cell phone call encryption is weak. Very weak.

The right antenna, receiver, and Analog and DSP window filtering can bring a signal up from beneath the noise floor.

No cooling with liquid nitrogen required, as they must do to primary antennas of the Deep Space Network to get the noise figure down enough to hear Voyager 1 and 2, and the tiny transmitters of the Mars rovers when they need to receive them direct, not through their orbiting relay bird with high gain antennas and considerably more RF power.

Amateur listeners have heard planetary probes direct with backyard dishes and Yagis. So it stands to reason that Geosynchronous eavesdropping is child's play for the top RF engineers in most 1st World countries. Implementation is hard.

Things like station-keeping while aiming and wobble/upset control of the optics and later, antennas, are tough - but not science fiction.

Those big "golf ball" radomes at Buckley AFB, Alice Springs NSW Australia, facilities in the UK and elsewhere, are not just for weather. If you can see where the high-gain ground station antennas are pointed, you know which satellites are in use today...

Satellite recon is one of the world's biggest and most expensive games of cat and mouse.

Thus, the next step... The Aurora type spaceplanes and their un-manned kin. Deploy to LEO. Take photo and RF recon. Land. The U2s at Beale AFB still play a role, too.

Since the Chinese started playing with blowing up on-orbit satellites (and making one he'll of a debris cloud around the planet in the process), systems like PAVE PAWS got "retasked" too.

In the case of that system, if you know the transmitter's ERP, and you know they banned any transmitters greater than just tens of watts ERP in the UHF Amateur bands within 100 miles of those things, you can calculate the size and distance from the array of the objects they're watching with them.

They're really really small and not inside the atmosphere, by my back-of-napkin RF calculations.

Other signs of obvious priorities changes at NRO include moving all/most assets under one unified Air Force Command at "USSPACECOM" many years ago. Start mixing receivers in a diversity receive configuration with digital/DSP noise removal and you've effectively turned down your receiver noise level and jacked up your effective receiver sensitivity.

Add giant hardened datacenters for crypto cracking gear to the soup, just for fun. The Puzzle Palace alone was running out of electricity a while back.

It isn't SciFi. It's done. We'll all read about it someday when we're old and gray once something better is operational for a decade or three and how hard it was to accomplish.

I'm an avid study of this stuff after reading the history of how the Apollo ground stations were built with tube gear, and with an all analog telephony network. Impressive stuff. Very impressive.

http://www.fas.org is like Jane's books on steroids for late-night reading if you're bored.

 

[JOhnH]

Yes, the government does have REALTIME satellite imagery that can zero in on any place on earth, but not all at the same time, on demand. It is tremendously expensive to task a satellite into position to see what they want, when they want to see it. It may take them several hours to get a satellite into position, and it would take years to photo capture and store every place on earth, thus Google Earth is a few years out of date.

edited to turn "mealtime" into "realtime". I think the spell checker got me.

 

[Richard]

Sat images in real time are available to non-military user groups. The cost is not central to why they are not dessiminated through Google and the like. The minute one real time image is released to the gen'l public there will be a hue and cry of invasion of privacy and other concerns, ad nauseum. And that tool will be compromised. It is better to just pretend the technology does not exist or that if it did it would be prohibitively expensive.

 

[kyleb]

The high res stuff you see on Google earth is from mapping aircraft. Full real-time coverage isn't practical with that approach.

Besides, I don't think anyone needs the ability to remotely stake out my house 24/7.

 

[Anthony]

With all the real time surveillance cameras watching us all the time, can't you just write a program to link them all. Betcha there is pretty good coverage.

Jesse?

 

[John Baker]

I had thought that most all telecommunication satellites were in stationary orbit, or staying in one place above the earth by rotating with the earth. My uneducated thinking also lead me to think that since us humanoids have been launching satellites up there for decades, that there must be an abundance of these things hovering over our heads.

But then, when it comes right down to it, I don't know squat about this sort of thing.

John

 

[Jim_R]

I had thought that most all telecommunication satellites were in stationary orbit, or staying in one place above the earth by rotating with the earth.

This is true to an extent, but a common misunderstanding, perpetuated by movie makers who don't understand fundamentals of orbital mechanics, is that this can be done over *any* arbitrary point on earth. That is not true.

Here are some basics to help you understand what is and isn't possible with satellite positioning.

First, a couple of assumption: Orbits do not have to be circular. However, for the purposes of this discussion, let's restrict ourselves to circular orbits. Let's also not quibble about things like the earth not being perfectly spherical or of uniform density.

1) Orbital mechanics will dictate that the center of a satellite's circular orbit will be the earth's center of gravity...for simplicity, let's call that the "center of the earth".
2) Orbital mechanics also dictates that at any given altitude (or orbital radius), there is one speed that will maintain that circular orbit. (A little slower or faster, and you will be in an elliptical orbit, and we said we weren't going to talk about those.)
3) Ignore any sticklers who try to confuse the issue by pointing out that a circle is a special form of an ellipse.

Now, for the hands-on part of the exercise. Find an old-fashioned globe like they had in schools back in the day, and a hula hoop. Play around with the hula hoop, putting it in different positions where the center of the globe is always at the center of the hula hoop. Note that this means the hula hoop is always either parallel to the equator, or else it crosses the equator twice, with exactly half of the hoop in the northern hemisphere and half in the south.

Now, rotate the globe to simulate its daily rotation about its north-south axis, and imagine a satellite moving along the hula hoop. Next, imagine that the hula hoop is the perfect size such that the satellite's speed takes it 24 hours to make one orbit. Congratulations...you have achieved a "geosynchronous" orbit (regardless of how you have the hula hoop oriented at the moment). In this orbit, the satellite will always pass over the same points of the earth at the same times every day (so if it passes over New York at 3pm today, it'll pass over New York at 3pm tomorrow, too.)

Now, orient the hula hoop so that it's in the same plane as the equator. Congratulations...you have now also achieved that very special geosynchronous orbit that is known as a "geostationary" orbit, meaning that to an observer on the ground, the satellite above appears stationary in the sky.

Note that the ONLY place you can accomplish this "geostationary" feat is over the equator. You cannot "park" a satellite over New York or the North Pole or anywhere else. (Refer to your hula hoop and globe again if you need to think about that some more.)

By the way, the altitude for a geosynchronous orbit is about 22,000 miles up, which is okay for communications relays but not very good if you're trying to read someone's license plate. That's okay, though, because really there aren't many interesting license plates along the equator...they're mostly in places like Moscow or New York or Kabul or Tehran. For comparison, the Hubble orbits about 300 miles up (about as high as the Shuttle can practically go) and the International Space Station is around ~250ish, but at that height they can only see the bits of the world they fly over for a maximum of about 10-15 minutes at a time.

 

[denverpilot]

I had thought that most all telecommunication satellites were in stationary orbit, or staying in one place above the earth by rotating with the earth. My uneducated thinking also lead me to think that since us humanoids have been launching satellites up there for decades, that there must be an abundance of these things hovering over our heads.

But then, when it comes right down to it, I don't know squat about this sort of thing.

John

Actually you're right in many ways. There are lots and lots of satellites and also lots and lots of debris. The heavensabove.com website is nifty for seeing how many birds. At least the non-classified ones.

Most of the really big satellites live out at Geosynchronous orbit where they park 'em in assigned locations and ground stations can point at the same relative location in the sky.

They typically carry "dumb" transponders. Basically very sensitive "bent pipe" radio gear that simultaneously receives, amplifies, and transmits exactly what was heard back out the transmit side. Go in on one frequency in the receiver's passband, come out on another in the transmitter's range. Ratio of power input to output is maintained so it's important for everyone sharing the passband to adjust frequency and power levels very accurately.

If you think about that for a bit you can also see that that style bird is easy to use for anyone, not just the intended users, and relatively easy to jam.

Most of the power, aiming, and frequency stuff has been greatly automated, but chat with an old satellite TV truck guy or gal for the fun 'n' games that used to take place with that in the 70s and early 80s.

Systems have also been designed such that only authorized users can access the transponder but most older birds don't have those schemes.

Besides the geosynchronous birds, there's also a huge number of birds in lower orbits that need to be closer to Earth for their signals to be received by portable devices.

The popular Spot devices for backcountry pilots, for example, are a failed satellite system that was meant to be a voice/data network. The main transponders on the satellites had a fatal flaw in a component that caused their transmitters to die after they were on-orbit for a while. Spot is a venture to use the secondary low-speed low-bandwidth transponders on board (originally intended for call control) that still work, as a low-speed two way data service. Making lemons out of lemonade, if they hadn't already have lost billions of dollars.

Iridium is another example. Satellite telephone calls virtually everywhere (their orbits actually don't cover all of the planet...) at huge cost. The system was a money-loser and if it weren't for continuous government contracts basically putting a financial crutch underneath the system, it'd be in perennial bankruptcy. Civillians can also use them, of course. Military versions of the phones have added high encryption and other features they need. The consumer "brick" phone has largely stayed the same over the years.

The Iridium satellites have very large solar panels and if the angles are correct, so called "iridium flares" of reflections of the Sun are so bright they're often visible in the daytime sky if you know where to look. There are websites with prediction software if you're interested in spotting one with the naked eye, even during daylight. Google "iridium flare".

And finally, of course there's also GPS -- which is popular amongst us pilots. Those birds are very low, to the point where their orbits degrade significantly due to atmospheric drag over relatively short periods of time, at least in terms of orbital mechanics. They have to be replaced when they run out of maneuvering fuel to keep the cluster running.

And as we've seen with recent military contractor's tests and the LightSpeed engineering and political fiasco, the civilian signals are very easily jammable.

All satellites suffer from electronic and battery failures eventually. Radiation creates "Single Event Upsets" in computers on board designed to detect bit errors in their running code and memory arrays. The CPUs utilized and the code are ancient in consumer computer terms, but "well tested and well known" in Space terms. Most are special "Silicon on Sapphire" construction to avoid radiation problems over years on orbit. 8-bit computers are still quite common for command and control. Your oven controls probably have more CPU horsepower.

More aviation related ones, WAAS is just a time signal sent through a geosynchronous bird's transponder. The eccentricities of the lower GPS bird's orbits means accuracy at the receiver end is a problem. Having another time signal from a known location that doesn't move much, allows our receivers to more accurately calculate their location.

One of the WAAS birds was literally out of control last year (or the year before? Too lazy to go look...) which was quite the buzz in the industry. It stopped responding to control commands and wandered into a different geosynchronous orbital location or "slot" as well as losing some axis control which wiped out some signals for users of another satellite when both transponders on both birds would be activated by the same uplink signal. A little maneuvering of the other satellite and careful aiming of ground stations using it, alleviated the problem at first with some minor outages when the angles were just right.

One day, the software watchdog timers that should have fired sooner, reset the command and control system and control was regained.

A lesson learned over time has been that control systems on board should reset after X amount of time not hearing from "home". Some of the older birds like the one handling WAAS aren't very sophisticated in this regard. They're too old.

It's really some neat engineering. I caught the "interested observer" bug and started to study satellites when I met a couple of the folks working on the AO-40 Anateur Radio satellite and got to hold some of the prototype parts in my hands. Simple old computers, rugged construction, heavy testing and QA. All things I thought were cool. Sadly AO-40 didn't survive long after a bad valve on an experimental engine destroyed critical components on-orbit. But she took some neat color photos further away from Earth than had been taken in a long time (since Appollo) on her way up and down her very elliptical orbit.

Lots of other cool birds up there. Shuttle fans who listen to the voice communications on-orbit have heard the term "Tee-Driss East" and "Tee-Driss West" mentioned when the Shuttle loses and regains voice Comm capability. It's the spoken version of TDRSS which stands for Tracking and Data Relay Satellite System. Shuttle would have been a lot less effective at communications without her support Comm satellites. Various places including Wikipedia have neat articles on TDRSS and the updates to that system over the years.

Very cool stuff.

 

[ScottM]

I caught the "interested observer" bug and started to study satellites when I met a couple of the folks working on the AO-40 Anateur Radio satellite and got to hold some of the prototype parts in my hands. .

You can see my ham sat antennas is this picture. Including the 60cm 2.5GHz dish I used for AO-40 downlink when it was still alive.

I almost had finished my WAS Satellite (4 states short) when it died.

 

[John Baker]

Wow, you guys, especially Jim and Denver Pilot, certainly put in an awful lot of effort educating me, I've learned a lot, so thank you for all the information.

Then my other question, which is of course hypothetical now that I understand the concept a little, is if it were possible, which it apparently isn't with todays technologies, do you think that a real time high resolutin Google Earth type service should be made available to just anyone who wanted to sign up?

John

 

[SkyHog]

Wow, you guys, especially Jim and Denver Pilot, certainly put in an awful lot of effort educating me, I've learned a lot, so thank you for all the information.

Then my other question, which is of course hypothetical now that I understand the concept a little, is if it were possible, which it apparently isn't with todays technologies, do you think that a real time high resolutin Google Earth type service should be made available to just anyone who wanted to sign up?

John

As a purely hypothetical concept - I think it should be available to everyone nationwide. Figure we can look out the window at anything we want right now, why shouldn't we be able to get a different angle of the same view?

 

[denverpilot]

In theory I'm for it. In practice, people cool up some awful ways to mess with each other.

Imagine stalker ex-boyfriend women beaters utilizing such a service. Or even just bosses for the 99.999% of us who've ever gotten into the office a little late after a bad night's sleep.

Our ability to assimilate new tech into our culture and define acceptable and unacceptable uses lags most tech by about a decade or two.

Especially tech that changes our view of things. We still haven't learned that a 24 hour news cycle is generally worthless on TV, for example. It agitates some so badly they're in a constant state of fight-or-flight.

Some things we just aren't ready to see without some thought about what we're realistically expecting to see.

Imagine the paparazzi types and famous people stalkers too.

We're still debating whether real-time public tracking of all civilian air traffic is a good idea. We're not ready for "eye in the sky" at all.

There'd be "good" from it too, of course. Rewind the video and follow the aircraft all the way to the crash site -- SAR would become a dead activity instantly. Who'd need an ELT?

Other applications might be the ability to shut down GPS. Just track yourself from above. Imagine the instrument approach procedures... "If you've zoomed and identified your aircraft from above, overlay the approach graphics and fly the approach."

 

[Richard]

Just track yourself from above.

They call that radar.

If you're gonna do all that why not stay in the sim? We fly, they stay on the ground.

 

[COFlyBoy]

Most of the really big satellites live out at Geosynchronous orbit where they park 'em in assigned locations and ground stations can point at the same relative location in the sky.

We don't have anything big out at Geo. We don't have rockets big enough to put anything large out there. You were right about Hubble being the size of a Bus. We used the heaviest lift vehicle we had to get it up, and it only made it 300 miles.

There are 720 Geo slots. Filled with little comm repeater satellites.

And finally, of course there's also GPS -- which is popular amongst us pilots. Those birds are very low, to the point where their orbits degrade significantly due to atmospheric drag over relatively short periods of time, at least in terms of orbital mechanics. They have to be replaced when they run out of maneuvering fuel to keep the cluster running.

GPS is in a MEO orbit with a 12 hour period. That puts them halfway to Geo, at 12,600 mi: http://en.wikipedia.org/wiki/Gps#Space_segment . The GPS birds' orbits are not significantly affected by atmospheric drag (solar pressure has a larger impact on the orbit). In fact disposal of GPS SVs involves boosting them to higher orbits and leaving them there. The GPS constellation is being replenished because the birds have reached their end of life, not because of orbit decay or propellent exhaustion.

 

[denverpilot]

We don't have anything big out at Geo. We don't have rockets big enough to put anything large out there. You were right about Hubble being the size of a Bus. We used the heaviest lift vehicle we had to get it up, and it only made it 300 miles.

There are 720 Geo slots. Filled with little comm repeater satellites.



GPS is in a MEO orbit with a 12 hour period. That puts them halfway to Geo, at 12,600 mi: http://en.wikipedia.org/wiki/Gps#Space_segment . The GPS birds' orbits are not significantly affected by atmospheric drag (solar pressure has a larger impact on the orbit). In fact disposal of GPS SVs involves boosting them to higher orbits and leaving them there. The GPS constellation is being replenished because the birds have reached their end of life, not because of orbit decay or propellent exhaustion.

Thanks for the corrections. By "big" I was thinking their giant (but very light and furled for launch of course) solar arrays. Hubble (and some Keyhole) birds were enormous.

I thought they "upped" the official number of geo slots by "stacking" and having some birds higher slightly and others lower. Takes more station-keeping propellant I believe though?

There was one Shuttle flight that was military (STS-3 perhaps, I can't find it now) that was almost polar. Vandenberg was behind schedule on their Shuttle launch facility and there was pressure to get them to do a military launch per the "Shuttle can do it all" financial wrangling of the 80s. Two crew, big ass satellite, Ken Mattingly was the Commander I believe?

I mention it because there used to be some great video of that launch and I can't find it anymore. Roll program went the "long way around" until the Shuttle was as northbound as they dared, over populated areas up the Eastern seaboard. Abort sites were either limited or non-existent, thus the limit of two crew members. Satellite had nuclear power, and a big demonstration brouhaha over that too since it would have rained lovely stuff down if they'd have had a LOCV event during launch.

I just wish I could find the video again. Neat to see that stack spin around like a top and nail a heading/trajectory like that. ;-) Shuttle's equivalent of aerobatics.

 

[ScottM]

Thanks for the corrections. By "big" I was thinking their giant (but very light and furled for launch of course) solar arrays. Hubble (and some Keyhole) birds were enormous.

I thought they "upped" the official number of geo slots by "stacking" and having some birds higher slightly and others lower. Takes more station-keeping propellant I believe though?

There was one Shuttle flight that was military (STS-3 perhaps, I can't find it now) that was almost polar. Vandenberg was behind schedule on their Shuttle launch facility and there was pressure to get them to do a military launch per the "Shuttle can do it all" financial wrangling of the 80s. Two crew, big ass satellite, Ken Mattingly was the Commander I believe?

I mention it because there used to be some great video of that launch and I can't find it anymore. Roll program went the "long way around" until the Shuttle was as northbound as they dared, over populated areas up the Eastern seaboard. Abort sites were either limited or non-existent, thus the limit of two crew members. Satellite had nuclear power, and a big demonstration brouhaha over that too since it would have rained lovely stuff down if they'd have had a LOCV event during launch.

I just wish I could find the video again. Neat to see that stack spin around like a top and nail a heading/trajectory like that. ;-) Shuttle's equivalent of aerobatics.

Not sure which one you are talking about but STS-3 was still one of the test flights, did not carry a "Big ass satellite." I can personally attest to the last part as I supported that mission and saw the payload bay when the orbiter was on the pad. Lousma and Fullerton were the only crew on board and it is the first mission to have landed at White Sands.

Later there would be military mission for the shuttle because the Vandenburg facility was not nor was ever made ready. Discovery was to be primarily used for the military missions. But after the Challenger accident all of that was scrapped and NASA supported the missions directly. Most of them where stuff for SDI. in the middle 80s I worked on some of the TPE and the RME stuff until Graham-Rudman budget act came and I went to the private sector. A lot of the real heavy lifting mission had been given back to the USAF Titan Program by then.

 

[denverpilot]

Yeah, 3 is too early. But it was early-on. Hmm, can't remember.

 

[ScottM]

Yeah, 3 is too early. But it was early-on. Hmm, can't remember.

I know STS6 had the first TDRS on it and I left the program right after STS7 to do my 'regular' duty with the USAF instead of fun and interesting stuff.

 

[COFlyBoy]

Thanks for the corrections. By "big" I was thinking their giant (but very light and furled for launch of course) solar arrays. Hubble (and some Keyhole) birds were enormous.

Gotcha. One of the oldest repeater sats, was nothing more than an inflatable balloon that was relective, very big and light.

I thought they "upped" the official number of geo slots by "stacking" and having some birds higher slightly and others lower. Takes more station-keeping propellant I believe though?

Some of the slots are doubled up with spare birds.
There are also places where there are 2 birds in the same slot with slightly different inclinations. This causes them to fly a little figure 8 over the ground, but I guess they still serve whatever purpose they were originally intended for.

 

[denverpilot]

Gotcha. One of the oldest repeater sats, was nothing more than an inflatable balloon that was relective, very big and light.


Some of the slots are doubled up with spare birds.
There are also places where there are 2 birds in the same slot with slightly different inclinations. This causes them to fly a little figure 8 over the ground, but I guess they still serve whatever purpose they were originally intended for.

Echo! Yup. Big ol' popcorn globe.

(Oh, I'm dating myself talking about popcorn cooked on a stove, aren't I!)



I believe the XM birds and/or the Sirius birds do the figure-eight thing. I forget which.

(Another couple of examples of bankrupt businesses who went through the bankruptcy carwash and now look like they're profitable.)



Satellites are heinously expensive. And we think airplanes are bad!

 

[Dr. O]

This has been a fun thread...
Just one comment on the observation that we don't have anything large in GEO because we don't have a lifter big enough... Actually we do have a lifter big enough to do the job - they just, flat out, refuse to use it... The Saturn V will lift 260,000# to LEO and send 200,000# off to the moon... It has been to the moon carrying men a total of 9 times so it certainly is a proven capable, man rated lifter...

As far as big enough, the lift ring on the top stage is 33 feet in diameter (5 room house)... The blueprints are still there... The engine builder is still in business... And why we threw away billions of dollars on a new heavy lifter that is now dormant, and having to pay the russkis to lift us to the ISS, just gives me a raging case of high blood pressure!

NASA, order some Saturn V's! sheeesh....

denny-o

 

[Bob Noel]

This has been a fun thread...
Just one comment on the observation that we don't have anything large in GEO because we don't have a lifter big enough... Actually we do have a lifter big enough to do the job - they just, flat out, refuse to use it... The Saturn V will lift 260,000# to LEO and send 200,000# off to the moon... It has been to the moon carrying men a total of 9 times so it certainly is a proven capable, man rated lifter...

As far as big enough, the lift ring on the top stage is 33 feet in diameter (5 room house)... The blueprints are still there... The engine builder is still in business... And why we threw away billions of dollars on a new heavy lifter that is now dormant, and having to pay the russkis to lift us to the ISS, just gives me a raging case of high blood pressure!

NASA, order some Saturn V's! sheeesh....

denny-o

Nobody is around to build it. The tools don't exist. I'd be willing to bet it doesn't meet today's safety standards (hard to believe given that we've been using SRB's for the shuttle).

We don't have the launch tower(s) anymore.

But other than that, yep, we're all set.

The dream is pretty much dead.

 

[BiffJ]

One thing that is seldom discussed in threads about satellites looking at cigarette size objects on the ground is reality. Get a set of binocs and look at a target a mile away....half a mile.... across the street even. Depending on humidity, temp, wind and any other of a number of variables you won't be able to see a pack of smokes at 100yds sometimes much less 100 miles regardless of telescopic power. The atmosphere that allows you and me to zoom about in joyous revelry also tends to screw up visible light and can affect even radio and other bands. Adaptive optics allows for some correction in real time but requires a lot of space, weight and is not really useable (yet?) for satellites. Is it possible to see clearer pics in radar, Infra-Red, X-ray or other electro-magnetic bands??? Sure its possible but probably not cost effective yet for civil use (meaning that it doesn't have unlimited funds from hapless govt subjects). Google Earth uses aerial pics because they get the best resolution for the buck and updates can be done a number of times without getting near the cost of one satellite. I think its kind of neat to be able to backtrack through the years on google earth.
One last thing on the satellite pic front, there was a time when you could subscribe to or buy images from a number of satellite companies who specialized in providing instant coverage for anyone who had the cash and needed geo data. If you were working on environmental issues and needed to track changes, needed survey type info on land areas for real estate or land use planning etc...you could get that through Landsat or others. What you want is basically available but not for free and not via google earth.

Hope that helps
Frank

 

[flyingcheesehead]

The technology isn't available yet to have live on-demand images of a location at any reasonable cost. Certainly not able to just on the whim look at random things and maintain live imagery for an indefinite length of time. The physics don't allow for this.

A satalite is only going to maintain view of a certain area for a certain length of time as it passes by. There are only so many satalites. A satalite in geostaionary orbit is *WAY* out there - doubt it could get pictures of great resolution.

Much of the great Google Earth imagery was done by airplane. Not satellite.

True... But the technology definitely is available... Just not to us. The license plate thing described in the OP was demonstrated to a friend of my dad's 20+ years ago. I remember going to pick him up at the airport and he talked about how they zoomed in on his house and read him his license plate number... From INSIDE HIS GARAGE. That was in the late 80's. Taking that and applying the progression of technology, I'm sure they can do better now.

Also, back in the day the Lockheed skunk works put a large banner on top of their building saying "If you can read this, you're ten years behind us." Later, they put a license-plate-sized sign up there to replace it that said "If you can read *this*, you're twenty years behind us." Wonder what they have up there now...

 

[jesse]

True... But the technology definitely is available... Just not to us. The license plate thing described in the OP was demonstrated to a friend of my dad's 20+ years ago. I remember going to pick him up at the airport and he talked about how they zoomed in on his house and read him his license plate number... From INSIDE HIS GARAGE. That was in the late 80's. Taking that and applying the progression of technology, I'm sure they can do better now.

Also, back in the day the Lockheed skunk works put a large banner on top of their building saying "If you can read this, you're ten years behind us." Later, they put a license-plate-sized sign up there to replace it that said "If you can read *this*, you're twenty years behind us." Wonder what they have up there now...

Notice the part where I said "reasonable cost", addressing the OP's question.

As far as reading a license plate inside a garage from a satellite, I'll call bull**** on that one.

 

[flyingcheesehead]

As far as reading a license plate inside a garage from a satellite, I'll call bull**** on that one.

Why? With what can be done with visible stuff, it wouldn't surprise me at all if they could do that with infrared.

 

[gismo]

Why? With what can be done with visible stuff, it wouldn't surprise me at all if they could do that with infrared.

IR's not gonna help unless the numbers and letters are at a significantly different temperature than the rest of the plate. IR cameras can take fairly normal pictures in the dark if there's a source of IR illuminating the scene but in that case it can't see through walls very well. In any case the sat cam would have to be looking at a significant angle from vertical to see the plate on most cars even without the garage. If the garage door was up and the car wasn't very far inside a plate ought to be just as visible to a satellite as one on a car outside.

 

[Doggtyred]

Notice the part where I said "reasonable cost", addressing the OP's question.

As far as reading a license plate inside a garage from a satellite, I'll call bull**** on that one.

Nobody said the garage door was closed. Truth is, to see a license plate you won't be looking at it from DIRECTLY overhead.

 

[jesse]

I would guess that IF they do have the capability of reading a license plate, conditions have to be ABSOLUTELY perfect, and in the real world they are generally not perfect.

I'd also suspect that they have very few birds actually capable of this and they're pretty occupied. I'd be pretty surprised if they have the available bandwidth to just "show them off" to some guy and read his license plate in his garage for fun.

As far as reading one in a closed garage. No way. Reading one in an open garage? Maybe but things would have to be absolutely perfect to get the angle. The vast majority of the time they'd be unable.

 

[flyingcheesehead]

IR's not gonna help unless the numbers and letters are at a significantly different temperature than the rest of the plate.

I figure that it probably would require that someone had been out driving it in the sun - WI plates have black letters on a white background, which would be able to create a temp difference for a short period of time.

 

[gprellwitz]

As far as reading one in a closed garage. No way. Reading one in an open garage? Maybe but things would have to be absolutely perfect to get the angle. The vast majority of the time they'd be unable.

Okay, that's what they want you to believe! Yes, they're telling the truth. Definitely!

 

[Richard]

There are two notable technologies not discussed in these last few posts (or perhaps in this entire thread which I have not read in entirety).

One is the optics. You would be amazed at what is available on the satellites. Plus, other than a passing mention of IR, ya'll are talking of what is visible to the naked eye. It is well known that sats can and do produce images far outside that narrow portion of the spectrum. Not so well known because of the proprietory nature of such systems is the incredible detail. And that leads to the other technology.

The software required to produce the images is as necessary as the optics. Unless you are active in the very narrow field of high security optical systems, you will never know. And if you are, you'll mostly keep your mouth shut. I happen to know because of a curious mix of knowing a few who's who and having been guided through several formal tours of processing facilities.

I'm talking of everything from high level mil intel to radar telemetry to map the ocean floor to ground penetrating radar, all gotten from sat based elements. And a few other applications I shouldn't mention except to say they are real.