Updated: October 19, 2015
If you are comically savvy, then the term Black Knight invokes some happy memories in your mind. Monty Python's King Arthur and the Holy Grail movie kind of happy to be more precise. However, you may also be thinking of the Black Knight satellite, an alleged UFO object placed in an orbit around Earth by some alien race sometime or such.
Since I'm always delighted in debunking silly claims, especially those related to extra-terrestrial visits and visitations, we shall now embark on another journey of hillbilly physics. As we've done several times in the past, including proving Drake's equation  by accident, showing you how to GIMP your images with mad skillz and such, we will now rip this nonsense apart using the magic of mathematics and logic. Follow me.
The Black Knight story
So it goes as follows. Approximately 13,000 years ago, an alien race from Epsilon Bootis  dispatched a satellite to our planet and put it in orbit, emitting a repeating radio signal invitation, calling us over to a party. For nearly 13,000 years, this thing just sat there, firing off what's virtually a first of its kind social media invite, waiting for humans to develop sufficient technology to actually be able to pick up radio signals, fly into space and collect imagery from the near orbit, and then, work their intelligence around the problem.
While the object is nothing more than a piece of thermal blanket shed from Endeavor's STS-88 flight , it seems to resonate hard with those who'd like to believe we are not alone in the universe. And you know what, let's say that their claim is true. Let us assume that there is indeed intelligent life out there, and that they do want to be friends with us. I am actually going to debunk the story based on that premise, because obviously, scientific facts from NASA are not enough.
Space, the final frontier
If you have read my article on the probability of intelligent life outside the Solar system, then you know that statically, under ideal conditions, the earliest habitable planet is located approximately 600-1,200 light years away on average. However, Epsilon Bootis is one of the stars in the northern constellation of Bootes, only 37.6 light years away. This places is much closer to Earth than the math would allow, but we will gracefully accept that claim. Now that we have some basic facts in place, let's ponder on some of the other points related to the Black Knight satellite story.
If we really assume our extra-terrestrial friends dispatched a satellite to Planet Earth all those years back, then they have literally wasted 13,000 years waiting for us to evolve. In fact, even only as far back as 150 years, there was little to no evidence we would ever be able to conquer space. Radio was in its infancy, and classic mechanics and chemistry ruled the university halls. In 1865, space flight was still a century away, quantum mechanics did not exist, and no one dreamed of digital computing.
For aliens listening to transmissions sent by their satellite, things only started becoming really interesting in the early 1960s, which they discovered sometime in 1997 or 1998 at the earliest, after the information has traveled 37.6 years to its destination. On a scale of 13,000 years, which is, let's admit, a fairly long time for a project to run, the results have only become interesting in the last 0.1% of its span. If aliens are anything like us, then we are talking about 300-400 generations of wasted effort. Would you let your project run that long?
Sure, you might. After all, you send a satellite on its away, and don't bother. One day, it may or may not return any meaningful data. But that's from a technical perspective. What about the social or cultural perspective? Do you think the aliens would remain attentive or focused on a project that has not yielded any kind of result in 13,000 years? The actual equipment might work, but would anyone bother listening to it, just in case they get some kind of a signal? Again, sure, they might. For a few hundreds of years, maybe even a thousand if they are really tenacious. But 13,000?
Look at the human race. We can hardly remember what happened in the last decade, let alone in the previous millennium. Imagine going back some ten thousands years into the past and maintaining active awareness of something that may have been deemed significant or important back then. To make it easier for you to relate, thing of our current Solar system probes. We have dispatched them to roam and probe and seek, and yes, we have scientists analyzing the numbers now and then. But it has only been about 40 years since we started. What will happen in 400 years? Or 4,000? We will sure have sent new, better, smarter, faster probes out, and eventually, we will probably forget about the very first endeavors in space exploration. More importantly, we might actually end up struggling to collect the data from ancient equipment. At the moment, we have the means and knowledge to use Pioneer, Mariner, Voyager  and other programs. But will we consistently maintain the needed tools a century from now? Or seven? Or seventy? Finally, will any of it be relevant?
Relevance of the alien threat
It's been 13,000 years since Black Knight supposedly assumed its orbit around Earth. So far, we have successfully evolved as a species, our numbers are higher than ever before, we possess nuclear weapons and we can selfie using our phones, and we are advancing in the fields of medical research, communications and science at an unprecedented pace. Which means that Black Knight isn't doing anything useful or significant that would in any way affect our existence on this planet. In the best case, it's totally pointless, and not any better or worse than a piece of rock. Whatever it's supposed to be doing, then it's completely boring.
There's also the small question of power. Something has to be powering the satellite, right. Images don't show any reflective surfaces, so we can probably take solar power out of the equation. Radioactive sources could be used, but if we look at our existing probes, which often use Pu-238, with the half life of about 87 years , the annual power loss is about 0.79%/year. Even if aliens use a system with 10x efficiency, it still comes down to just 1,100 years before all power is lost. They would need something with x200 efficiency or higher to be able to continue maintaining a reasonable level of output and functionality. Not undoable, but definitely not trivial.
Why 13,000 years
Now, let's go back to the age claim. 13,000 sounds like a very precise number. Indeed, how did it come up? If the UFO claims are true, then the satellite has been properly and thoroughly analyzed. This means some kind of dating technology was used, and if this is an inanimate, non-organic object, then we are probably talking about physical contact, spectroscopy or both - carbon dating is out of the question. Now, if the object has been probed [sic], then we know its chemical and physical properties, we know what it can or cannot do, and we have its electromagnetic signature, which in turn would tell us if it's radiating any kind of emission, including radio signals, radioactive decay or such. In other words, if we can backup the claim of its age of 13,000 years, then we know everything about the object, and there are no speculations, making the whole mystery piece moot.
The age claim may determine when the satellite was created, but it does not really tell us when it may have arrived in Earth's orbit, unless we are talking about really sophisticated methods for analyzing radiation damage, solar debris damage, and other crazy things that go beyond our ability today, because there is very little to differentiate the space environment in Earth's orbit from one millions of light years away. Furthermore, the contamination by radiation from stars and from collision with interstellar and planetary debris would definitely make accurate dating almost impossible.
Another problem with the satellite is the actual time it took to arrive to Earth. It may originate 37.6 light years away, but how long did it take for it to travel here? It sure couldn't fly at the speed of light. So we are talking about a very long and slow initial journey. Even at a rather stupendous speed of 0.1c, it would last 376 years. At 0.01c, which is still a staggering 3,000 km/sec in vacuum, it would take another 3,760 years on top of its 13,000 years of wait in orbit. Now, imagine what would happen to a satellite if and when it collided with a tiny solid particle while traveling at such speeds.
If we look at our own space probes, Voyager 2 has a heliocentric velocity  of about 30-35 km/sec in the best case, two orders of magnitude less than the over-optimistic 0.01c estimate. This means that a satellite like Voyager would need at least 376,000 years to reach a planet 37.6 light years away. Realistically, it would be more like 400,000 years or higher.
Therefore, we are talking about an alien program that may have started hundreds of thousands of years ago, rather than 13,000 years ago, which complicates our dating adventure some more. Then, the power considerations also become more difficult. During the interstellar travel, solar energy might not be sufficient to operate the communications equipment, so it means the system would have to use radioactive sources, and be roughly x60,000-80,000 more efficiency than ours. And the aliens would have to maintain a cultural, historical and scientific relevance of the space exploration program for much longer than that. We are talking evolutionary-long times.
Then, if aliens were aware of our planet some 300,000 years ago, we didn't even exist as a species back then. Why would the aliens bother sending a probe to invite us anywhere, in a language that we can supposedly comprehend, when humans didn't technically exist when the project was originally conceived and launched? Yes, we can assume these extraterrestrials are super modern and super sophisticated, then why would they use a satellite that is so easy to discover?
In fact, would you risk a mission that lasts tens of thousands of years on a single piece of machinery? Would you send a lone satellite that could break down, or maybe dispatch tens or even hundreds of those. I mean, how long can electronic equipment last without breaking? Hundreds of years? Thousands of years? Even if somehow the aliens had miraculously manufactured extremely highly durable systems, they would still some kind of redundancy to ensure their project did not prematurely end after only a few thousands of years. Sending a single satellite would be absolutely silly. And yet, we can only see one Black Knight, and its orbit coincides with that of a human space mission from the 60s. How convenient. Enough bollocks for one article.
Since you supposedly like this stuff so much, here's some more awesomeness for you:
And here we are, at the far end of this article, wiser and more educated. Even if you give UFO lovers all the benefit of doubt that you can, the story unravels as you explore the details. Say the aliens decided to send their satellite here. Fine, let it be, for whatever absurd reason. Then, the distance, travel speed and time, power, and other considerations all add their little problems and inconsistencies into the equation. People just seem to forget, or cannot grasp, how big and empty the universe really is.
Anyhow, Black Knight is an almost interesting tale, but then, like all conspiracy theories, it's 13% fact, 71% lack of knowledge or deliberate ignorance, and 16% pure, proper sci-fi nonsense that works well in various books and TV series, but does not quite survive the cruel tests of reality. Lastly, even if you try very, very hard to accept all of the stuff at face value, there's one last fundamental question that really nails the coffin shut. And that is, how do some of these people know this satellite comes from Epsilon Bootis? Did it whisper its story in their ears? There. Problem solved. I hope you enjoyed it, especially the references. See ya.
P.S. All of the images, courtesy of nasa.gov, in public domain.
Yes, some of you complained - by email - how my articles are unfounded and such. Nope. They are extremely founded, it's just that I never bothered adding references, assuming you were intelligent enough to search for details on your own. Well, anyhow, here's an article with all the extras. I think you will find this fine piece more serious and credible now.