Satellites : general discussion and musings

[SacredCowSlayer]

Here's the standard "explanation" you will get from rocket scientists: "Space is very big - so the chances are very small for satellites to get struck by any object."

Now... why does that standard "explanation" fail to satisfy my neurons?

Dear Simon,

I think your lack of satisfaction is (probably) similar to mine. That is—if our atmosphere suddenly didn’t exist (but otherwise things remained the same), I’m quite confident that “space is very big” would do nothing to alleviate my concerns.

If I had a multi-billion dollar investment whizzing around the earth (for whatever reason) in a zone outside the protection of our atmosphere—well, the size of space would be no comfort at all. Total destruction would be a question of when, not if.

[nokidding]

Could the chance of a satellite meeting any random object in LEO be approximated as a volumetric ratio? ie vol of satellite / (vol of outer orbit sphere - inner orbit sphere}. This figure would then be multiplied by the number of random objects. The chance of being in in wrong place at wrong time would be very small, but obviously this changes if you are in a shipping lane.

Of interest is what is the orbital decay time. How long does a random object stay up? Not long if you look at the early Explorer satellites. Perhaps there is less junk than made out. The whole technology is obviously secret. To be of any use satellites appear to need both attitude control and altitude boosting, something like a drone with low propulsion energy requirement. How long can the fuel last? (for Newtonians only).

[simonshack]

Could the chance of a satellite meeting any random object in LEO be approximated as a volumetric ratio? ie vol of satellite / (vol of outer orbit sphere - inner orbit sphere}. This figure would then be multiplied by the number of random objects. The chance of being in in wrong place at wrong time would be very small, but obviously this changes if you are in a shipping lane.

Dear Nokidding,

I believe we have, over the years, amply demonstrated (in numerous ways) in this forum's discussion threads that there are no man-made satellites circling our planet.

However, just to play with the idea - and as a fun computational exercise - it would be interesting to calculate the probabilities of a sphere with a radius of only about 6500km (the approximate radius of Earth + its surrounding atmosphere) being struck by, say, 9 billion projectiles every year - i.e. the estimated number of meteorids entering our atmosphere annually. One would also have to take into account that all these meteroids travel at a PERPENDICULAR angle vis-à-vis the supposed trajectories of the alleged 20,000 or so man-made satellites circling around Earth in all directions (and at various hypersonic velocities).

Here's where one may calculate the surface area of a sphere:
https://www.calculatorsoup.com/calculat ... sphere.php

Now, keep in mind that - as far as I know - no satellites are known to have been downed by a meteorid / or any space debris.
Any math-geeks out there who'd take up the challenge to calculate the odds / probabilities of ZERO such incidents occuring over, say, the last 20 years?

[HonestlyNow]

To be of any use satellites appear to need both attitude control and altitude boosting, . . .

Freudian typo, perhaps? Yes, attitude control to keep the deception alive.

[nokidding]

Attitude Control is the big problem for a satellite, preventing and correcting spin, and accurately aligning instruments, antenna and booster nozzles. But once you think of a free fall drone with the requisite active control systems, boosters and fuel it is not so improbable when compared with airborne systems - however short lived and limited in capability and navigation. When is a satellite not a satellite?

[simonshack]

When is a satellite not a satellite?

Dear Nokidding,

Hope you don't mind me replying with another question:

When is CGI (Computer-Generated Imagery) not CGI?

You also wrote: "Attitude Control is the big problem for a satellite, preventing and correcting spin, and accurately aligning instruments, antenna and booster nozzles."

Great, I'd certainly agree that these aspects would be very problematic. Yet, we're told that the badass "rocket scientists" of this world have masterfully solved all of these problems - and are now managing and monitoring several thousands of man-made satellites revolving along precision-orbits around Earth. For instance, let's take a look at the so-called "GAIA satellite", the pride & glory of ESA (the European Space Agency): it is said to be hurtling at hypersonic speeds around Earth (since 2013) to collect high-precision astrometric data of our cosmos - and to be capable of collecting stellar parallax measurements within an error margin / resolution of "better than 0.001 arcseconds" (yup, 1 milliarcsecond!). We may also read that its mission was originally planned to last 5 years, but "since its detectors are not degrading as fast as initially expected, the mission could therefore be extended" until 2025. Oh, and we're also told that "the limiting factor to further mission extensions is the supply of fuel for the micro-propulsion system, which is expected to last until November 2024."

Now, to address your above-mentioned issues of attitude control, would you like to speculate (I know, neither you or I are rocket scientists - but give it a try!) as to exactly how this would be achieved for this "GAIA satellite" hat-shaped contraption (with its fancy fold-out solar panels)? Where are the "attitude-correcting" boosters? And where would that fuel supply (enough to last 10 years or more) for the "micro-propulsion system" - whatever that means - be stored?

The "GAIA satellite" - as depicted on ESA's official website : https://www.esa.int/ESA_Multimedia/Imag ... IA_Cam01_2



Need I add that the above "images" are extremely crass CGI artwork (far worse than that used in childrens' modern computer games)? Why so? If your answer will be "because it's impossible to photograph satellites in the sky in HD", why wouldn't ESA at least offer us some hyper-realistic imagery of their wondrous, billion-dollar Gaia satellite by simply using photographic composites of the REAL THING as it was (purportedly) being assembled here on Earth? Mind you, the same goes for ALL the imagery proposed by NASA, SPACEX and the other "space agencies" of this world - as thoroughly demonstrated on this forum for over a decade now.

See, I don't know about you, but I personally have had enough of having my intelligence offended by the ridiculous claims, narratives, pscience-fiction and pathetic CGI imagery that's being continuously thrown at the public by these self-anointed rocket scientists and their "space agencies". Having said that, anyone is of course free to believe that they have truly launched thousands of satellites up in space which, after an initial "push" by a rocket launcher, keep circling around Earth at hypersonic speeds (for years or decades on end) while having their orbits and attitudes finely regulated by remote-control from ground-based stations... And this, without EVER being struck by any of the billions of meteorids constantly "crashing" into our atmosphere. Quite franky, I'd rather believe in the existence of Santa Claus.

[Altair]

Somehow related, they've released what's supposed to be the original code for the Apollo control and guide computers.
Leaving aside the fact that a 32Kb, 2MHz computer (a ZX81, for those who remember, was more powerful than that) wouldn't be capable at all of performing the complicated and time sensitive matrix calculations needed for controlling something like a Saturn V rocket, peering at the code dissolves every doubt that such a thing could ever work! Even the code for a light aircraft autopilot is MUCH more complex than this! I'm a software developer myself, but if there is another one else in the room, I'd ask him to have a look at this fragment of code, which is supposed to guide the module through a reentry into the Earth's atmosphere.
https://github.com/chrislgarry/Apollo-1 ... ONTROL.agc
Just 1600 lines of assembler code (which has a very low functional density compared with high level languages) of which a significant part are comments.
Other parts of the code are equally (or even more!) absurd: attitude control, orbital maneuvrers and so on.

[nokidding]

Such an elaborate charade just to drain the Treasury when you can do it so easily with QE. Perhaps space belongs to an earlier age when there was still some oversight of budgets and hoaxes had to be convincing, at least for committees. Now they don't seem to bother much at all and it is just for kids. I guess corruption is an end in itself and anyone who is any one (or wants to be) knows full well. It is the world as it is, only innocents like us throw their hands up.

I am still interested in what the real capabilities are behind the charade. It's fun to spot the chinchillas on mars, the CGI - the flight computer and coding is a brilliant one thanks altair, but it's impossible to know what is really going on, or even what the objectives are. Surely it's a mistake to think that space is as virgin as a century ago and there has been no progress at all.

I think we know a good deal about the constraints for exploration, eg fuel and radiation and accuracy of navigation and control systems. The accuracy of any one shot trajectory has to be the same as the astronomical observation. Or you need a navigational control system and all that entails with shifting frames of reference and varying gravity fields and relative velocities. But still you can exceed escape velocity.

But even re-entry is a more complex topic than I imagined. You soon can calculate that heat shields and radiation dissipate insignificant energy, but if you can make it down into the thicker atmosphere only a small pressure differential slows you, with just a few psi you can imagine air cooling would work. The problem is hte upper atmosphere where slowing is small, but there is nothing to take the heat away except some radiation. Is there a descent path that could achieve this? I doubt it, but the sums become too hard to do. If you don't have an extremely accurate control and navigation system you are still going to burn. And what about the risk engineering? The whole concept of a parachute landing in a capsule is fraught with risk. Even with a crane transfer you can't safely do it.

Wikipoo tells you the Mercury project capsules had an Aluminium honeycomb heat shields (600C melting point) that gave me a good laugh.

[bongostaple]

Surely it's a mistake to think that space is as virgin as a century ago and there has been no progress at all.

Well I'm pretty sure that going into space is exactly as impossible today as it was 100 years ago. This would be supported by the fact that contemporary imagery of 'space missions' looks fake, imagery of 10 years ago looks fake, 20 years ago still fake, i.e. all of it looks fake. The US Air Force ran the X-plane program and as soon as it started looking like they'd hit a ceiling of maximum flight altitude, they dropped space like a hot rock and NASA was formed to carry things on. If it were possible to travel to orbit, the US Air Force would by now at least have taken something heavy up there and dropped it to see what kind of mess it would make. But they haven't.

[simonshack]

Surely it's a mistake to think that space is as virgin as a century ago and there has been no progress at all.

Dear Nokidding,

Am I to interpret this statement as yours as : "the entire decade of research on this forum dedicated to exposing the Grand Space-Travel Hoax ... is a mistake"?

I hope not. But if so, let me remind you that there's been no progress whatsoever (for the last 200 years or so) to even determine that Earth would be hurtling around the Sun at the formidable, hypersonic speed of 107,226 km/h (i.e. 90X the speed of sound) as still claimed by this planet's scientific community - in spite of the complete lack of evidence in support of such a theory.

[nokidding]

Dear Simon, No, not at all. The hoaxes have been exposed brilliantly on here. But I would still like to know what is physically possible and what is being done in secret. I have seen nothing to say that 1) a rocket cannot exceed escape velocity however uncontrolled its trajectory 2) a free fall drone cannot circle the Earth, however short lived and inaccurate and limited its capability.

I think it likely that a lot of surveys and tests have been done, and they reveal an unfriendly environment and the inability to navigate to and orbit other bodies including the Moon. Free fall drones with attitude control were probably not possible until processors became powerful enough. They probably became an extension of the high altitude spy plane programmes which continued. Re-entry results in burn up - there are no reverse thrust and navigational solutions. That would have been confirmed early on.

The problem with the Hoaxes is that they prevent news of any real programmes being released that would reveal the real status of exploration. That doesn't mean that there are no real projects, though it would put a dampener on anything without military objectives.

We see the post WW2 power monopoly come into operation that has now come into the open - no government or institution questioned the fakes. Everybody knew where they stood.

[patrix]

I think it likely that a lot of surveys and tests have been done, and they reveal an unfriendly environment and the inability to navigate to and orbit other bodies including the Moon. Free fall drones with attitude control were probably not possible until processors became powerful enough. They probably became an extension of the high altitude spy plane programmes which continued. Re-entry results in burn up - there are no reverse thrust and navigational solutions. That would have been confirmed early on.

You find it likely based on what? GPS and Satellite TV works using ground based tech. A rocket has a max altitude just like a plane and any payload brought up would fall down again.

Weather balloons and high altitude robotic planes exist but I don't see much practical use with them.

[Intothevoid]

Somehow related, they've released what's supposed to be the original code for the Apollo control and guide computers.
Leaving aside the fact that a 32Kb, 2MHz computer (a ZX81, for those who remember, was more powerful than that) wouldn't be capable at all of performing the complicated and time sensitive matrix calculations needed for controlling something like a Saturn V rocket, peering at the code dissolves every doubt that such a thing could ever work! Even the code for a light aircraft autopilot is MUCH more complex than this! I'm a software developer myself, but if there is another one else in the room, I'd ask him to have a look at this fragment of code, which is supposed to guide the module through a reentry into the Earth's atmosphere.
https://github.com/chrislgarry/Apollo-1 ... ONTROL.agc
Just 1600 lines of assembler code (which has a very low functional density compared with high level languages) of which a significant part are comments.
Other parts of the code are equally (or even more!) absurd: attitude control, orbital maneuvrers and so on.

Capacitors, found on every circuit board since transistor radios were mass produced have a lifespan of 15-30 years. Heat aids in their demise. Energized circuits produce heat. How does Voyager and all our aging satellites overcome this problem? Please excuse my ignorance if this has already been explained.

[sharpstuff]

The stars in photography

Dear Clues members and readers,

Fascinating stuff above this post of mine. Thank you.

I hope the following is not derailing this thread.

I am fully aware that the following has been a large issue regarding the debunking of the ‘rockets in space’ and the photography thus ensuing. However, in this particular case, I would like some help in answering some questions (perhaps naïve) regarding the ‘stars’ problem in ‘space’ photographs.

I just read about the new alleged US Mars expedition, along with the apparent Chinese effort. Once more we find numbers of pictures of the planet, the modules and so forth, even the highly scientific (!) and puerile word ‘selfie’ which contain no stars also.

Now, I fully understand that this may be a moot point, since we should all know by now that anything ‘man-made’ outside the ‘atmosphere’ is impossible except in the imagination. However, when I research the ‘no stars’ issue, I get mountains of technical writing upon the word ‘exposure’, such as and in short: ‘Everything (planets, space-craft etc.) are so bright, they need short exposures, therefore we can’t see the stars because they are not bright enough.’ Now, I do know a thing or two about exposure but I am looking for three and four.

Question 1: Just how far is that quote a truism?

I am also, not convinced about Earth-bound telescopes beyond the optical (‘radio’ and whatever else they claim to have). Obviously if we can’t get into space with anything, no extra-terrestrial others exist in real.

Question 2: How do, for example, radio signals get resolved into credible photographs (if any)?

Question 3: How do we photograph the stars from Earth?
Question 4: How do we account for the atmosphere (in its various guises) in photography of the stars?

Be well.
Sharpstuff