I always thought this was the most likely explanation.
Advanced civilization builds self-replicating probes, probes spread out over the whole galaxy. Stationed in every system to catalog signs of life evolving.
Advanced civilization builds self-replicating probes, probes spread out over the whole galaxy. Stationed in every system to catalog signs of life evolving.
> We derive physical constraints on interpretations of “highly maneuverable” Unidentified Aerial Phenomena (UAP)
The direct context of the article is meteorites (like Oumuamua), not the “fast blurs on aircraft sensors” you seem to be referencing.
Here is a piece from the conclusion:
> For example, one of the most common sets of data within the military holdings comes from FLIR (forward looking infrared) pods. These sensors provide an accurate resolved image of relative thermal measurements across the scene. Typical UAP sightings are too far away to get a highly resolved image of the object and determination of the object’s motion is limited by the lack of range data.
Not to mention, 'Oumuamua was emphatically not a UAP, it was a pretty-well-identified spatial object. UAP in fact refers exclusively to sightings that are not even clearly known to be "objects" at all, hence the move away from "UFO".
>"Parallax data from the James Webb Space Telescope may identify the nature and 3D trajectory of more ‘Oumuamua-like or smaller interstellar objects crossing through or trapped within the solar system. Below we show that any supersonic motion by such devices through the Earth’s atmosphere would inevitably be accompanied by bright optical emission and detectable characterization signatures."
He first describes how such an object (i.e., Oumuamua-like meteorite) travelling through the Earth's atmosphere can be measured through its luminosity signature. He then describes how RF and thermal (i.e. FLIR) signatures can also be used.
No, not a fast blur on aircraft sensors; rather a fast blur on telescope sensors.
All those telescopes saw was a very dim dot of variable brightness. They couldn't even see what shape the object was and even today nobody really knows what it was shaped like. From the period of it dimming scientists have inferred what shape it might have, but they don't really know because there are many geometries which could explain the observed data. It might have been cigar shaped, or it might have been more of a flat disk (a hypothesis favored by Avi Loeb I believe, one of the authors of the OP article). Nobody really knows because nobody actually got a good look at it. The limited data the telescopes were able to get leave a lot of room to interpretatation making it perfect UFOlogist bait, just like those videos from the airplane sensors. Actually the airplane sensors got a much better look at their objects than any telescope got of Oumuamua.
[0] (timestamped) https://www.youtube.com/watch?v=3vD4df_63wo&t=382s
But it seems like one of the conclusions of the linked paper in the OP (which is trying to put parameters on this very question) is that it actually would be hard to notice them, for certain scales of probe (on the order of 1 meter), at least while they're in outer space:
> At a distance d from the Sun and the telescope, objects that are a meter in diameter and reflect a fraction a ≈ 10% of sunlight impinging on their surface would yield a flux of optical light of ∼ 0.2(d/1 AU)−2 nJy, well below the detection threshold of even the James Webb Space Telescope
But it goes on to suggest that we could notice them, even at sizes less than a meter, with radar technology, once they're in the atmosphere:
> In contrast, the radar signatures of a meter class object would be detectable with our deep space radars and space fence, much like IM2 was, out to beyond geosynchronous orbit at an altitude above 36,000 km. Such objects could also become optically detectable as they get close to Earth, especially if they create a fireball as a result of their friction with air.
But, such FLIR systems also produce a lot of false positives, i.e. actual everyday meteors in the atmosphere. So the challenge is narrowing down the data to find the most anomalous objects. And indeed that's what Loeb has done with the Galileo project, as he's identified one such object that landed a few years ago, and is chartering a ship to go try to find it in the Pacific Ocean. Estimating the chance of success of his quest is an exercise left to the reader, but we'll have to see what comes of it.
It seems to me that UFO behaviour isn't consistent with likely alien goals. I would expect them to either announce themselves openly or else be entirely invisible.
If you want not to shock people, you don't sneak up on them, but rather you start by giving the faintest hint, alerting their attention to your presence.
"Having lights on" has the additional benefit of obscuring your vehicle quite effectively from camera sensors.