Despite being a retired manual laborer, I've always had a keen interest in Astronomy. Finding Fraser Cain has been a bright spot for me because I am able to continue with my fascination from the comfort of my home. Thank you.
Fraser Cain is one of the best astronomical journalists around. He knows enough to ask the questions that get interesting responses from scientists to us interested laypeople.
Oumuamua was only traveling at 0.03% of the speed of light. If it came from another solar system, it would have spent up to 20,000 years traveling in interstellar space. So not a spaceship and only a little bit faster than comets in our solar system. At that speed though, let's say an object several hundred metres across and hit the Earth by chance, it would be fairly devastating.
Great guest. Dr David Jewitt doesn't give near enough interviews. He isn't known to suffer fools so it's a great honour to your skills that David would come on your Podcast. Well done.
Yes, such a great interview. My favorites were whenever he would say, "The most likely explanation is a combination of those [things we just discussed]" - I think it shows that finding real answers requires knowing all the theories but not be overly attached to any one of them, and then weighing them together. Also, to see his enthusiasm for the process of discovery still intact, even as an old dude. So cool.
Question: What's the most practical way to capture samples from interstellar interlopers? I bet it will be somewhat disappointing when we get our first samples and they look just like stuff we're already familiar with. Because why wouldn't they be since that's where we came from?
100% . It’s astounding these brilliant scientists think laptop mics are acceptable for interviews. So many opportunities for the transfer of knowledge ruined by poor planning and a laissez faire attitude towards audio quality . It's the same problem on the Event Horizon channel. Sound checking the guests would go a long way towards presenting an acceptable program. I bail as soon as I hear poor quality audio.
I thought it was perfectly fine to follow. What is astounding is that people assume that scientists for that one good big interview done online should have some studio level equipment. No. Just no.
Astronomy / Cosmology based documentary series become "dated" very quickly. It's an exciting field. It's crazy watching television shows from 10-15 years ago, talking about 'possible' gravitational waves (now confirmed), blackholes (we have pictures of them)...
Could Theia (the huge chunk lodged in earth's mantle, caused the moon, started driving tectonics) be an example of a large interstellar? I guess the answer is "yes" it could be, but it's interesting to see if there's anything we could surmise from that we know on earth and moon and possible impact energies to see if this could be tilted over a theoretical max interplanetary source...
The number of moon craters that seem to be in an aliment have always fascinated me. I now wonder how many of those could have been trailing satellites rather than breaking up while falling in. I assume someone has studied those of 3 or more to see if they are random and if not due to the high crater numbers this might be something to play with using AI.
I find it interesting that it would take like 10,000+ years for Oumuamua to travel 1 light year away from the Sun. Heck, as long as we don't screw things up too much we can get to that thing way before then. Calling it now; The year 2430, human spacecraft reach Oumuamua.
Funny thing is I was just checking out a Fireball report on ASGARD where the velocity was 81.4 Km/sec. Turns out it was a measurement error. "...automatic algorithm failed to properly track the meteor". I wonder how often that happens? Oh well.
Asked one of the astronomers on the Kama'aina Observatory Experience tour thru the CFHT telescope how we had found TWO interstellar visitors in such a short time. He replied that they hadn't been looking for objects in non-parabolic orbits. How do you not spot something tracking thru an image no matter where you point the scope? I mean, do we have an AI looking at old images and comparing them with new?
I like your remark about undiscovered objects between us and proxima Centauri. Imagine the objects and disturbance by those objects during the development of our solar system, as it is now. Can someone calculate what time ago and what size and mass such passing objects between our Oort Cloud and Proxima's 'Oort Cloud' need to have to sling interstellar materials towards the sun? So fascinating. Thanks again for all the excellent videos.❤
If there is a one hundred meter interstellar astroid for every 10AU cubed, there must be an awful lot of them in and around the Milky Way. Is the total mass of them enough to constitute the dark matter?
Follow Oumuamua's outbound trajectory ... 'Oumuamua is heading toward the constellation Pegasus and is now far beyond the orbit of Neptune. The best-known of the Planet 9 theories predicted the existence of a distant planet that was influencing the orbits of Uranus and Neptune.
How had it been if we could hitchhike on these interstellar visitors? Send up rockets to meet them and attach ourselves to it on its way back out in the universe? Wouldn't that be a cheap way to explore space? Perhaps we could even have rockets floating dormant out in space, waiting for a visitor?
@@twonumber22 - I checked, the voyager satellites move at ~15km/s, while the oumuamua for example, move at ~90km/s, thats 6 times faster, if interstellar visitors are too slow, what was then the point with the voyager satellites?
@@doncarlodivargas5497 Voyagers were for exploring the outer solar system, and they completed their missions long ago. Now they're just toys but we're still learning from them.
What would be so nice If it were possible to lay a net of high strength material in the path of an interstellar interloper, This net would have a tail from which end a payload could be suspended and Hitch an Interstellar Ride, where the object provides a high acceleration and the Delta-V. A propellentless ride at that ! The net being hit by the hypervelocity object WOULD be a engeneering challenge, but maybe not insurmountable.
I suspect we will find Oumuamua was a contact binary, loosely coupled that explains its unusual behavior as it likely cracked apart on approach to our sun. This could explain the light curve anomalies and likely as well the trajectory issues as its mass going out was not equal to that coming in. We should look for the other half, but I am not nearly a good enough mathematician to calculate where to look for such a thing. I suspect Avi could give better insight on the legitimize of my hypothesis though.
Question: Why do astrophysicists/ cosmologists assume that the young very dense, compact universe acted the same way our way more spread out universe does now? Every time I hear about the distance ladder (and many other things) it seems there are some basic assumptions they use that do not seem axiomatic to me, I think “ have you proven THAT yet?” Then they use it as a base for all this other more complicated stuff. I wish I had a more concrete example but I have a biology science brain and do not even pretend to comprehend a lot of this stuff. I find it fascinating though.
Oumuamua is approx 1/4 mile long with a polar spin rate of approx 8hrs. Please, someone do the g-force math for me. Strikes me that it is a strong, homogeneous structure to not have flung apart. This must give strong indications of it's make-up and formation. It was touched on but I'd like to have heard more of David's thoughts on that.
So what are the chance of big object travelling through the solarsystem ? 1/10 000 for objects bigger that 50 km? - A 50km rock would sustain a family leaving the solarsystem to colonise and alienes could do the same coming to us on them
Oumouamoua might actually be an alien UFO. Imagine this: someone can send an object the size of Oumouamoua out of their system at very very high velocity so that it can actually reach other far flung system out there. The always main problem is the fuel capacity needed for course correction and deceleration. If you cannot use that reserve fuel then you have to get it somewhere else, such as the gravitational sling shot or deceleration around other star on your way to somewhere else. You cannot know where huge planet size like Jupiter would be in the system, but the main star... always. So a slight push for course correction over some decades can send the object around a star to either gain or lose velocity as well as main course correction. The problems of physics don't just dissapeare because of aliens.
There being lots of rocks between stars could also help explain the Fermi Paradox. If the area between stars are orders of magnitude more cluttered with rocks it would be all the more difficult and dangerous to travel there. More math is needed.
I wonder what it was that gave Borisov such velocity for an eccentricity over 3!* We could send a Starshot after them! :D Would have been really interesting if they'd both come in at similar angles, as that could have meant a linked origin, which would lead to the probability of more incoming! * Edit: .. the mechanism [for ejection] i.e Borisov; going to get my answer now; I also wonder what next weeks winning lottery numbers are (ah.. UK National lottery/31/8/24; don't want the right numbers for the wrong lottery) :D
OK, could someone let me know if my math is off or what. According to Dr. Jewitt there might be an interstellar object for every 10 cubic AU of space (at <a href="#" class="seekto" data-time="1790">29:50</a>). If the Oort could is a sphere 50,000 AU in Radius, would that mean over 12 million interstellar objects could be within the solar system and Oort cloud? That would be mind boggling...
The comets like Borisov are cool but kinda terrifying. I mean they are completely unpredictable. No amount of categorizing near earth or asteroid belt objects will help.
The distance to the next star is 600 times the Oort cloud distance so why wouldn't the Oort cloud form from material around the sun? The original cloud of material would cover 50000AU easily.
What sort of impact crater would the average visitor interstellar object cause in a head-on collision with Earth during the Sun-ward phase of the trajectory? And how much time would we have to do something about it before it happens?
Is the orc cloud like a bubble around the solar system? And if so why wouldn't the parts of the orc cloud in front of the sun that's moving around the galaxy fall inward towards the sun?
Does anybody here have any thoughts about the mission of Zuma, USA-280? The timing of the launch and the available information and the purported fate of the mission all make me think it was somehow related to Oumuamua.
Not really. Everything in our neck of the galactic woods is going in pretty much the same direction around, like cars on an interstate. Some stars will be going marginally faster (like Sol), some marginally slower depending on who is on what part of their elliptical orbit. Since we are doing 255km/sec in a 220ish zone, we are headed down the "road" slightly faster, and are probably closer to our perigalacticon. (That above is an IRL orbital dynamic word, not some LARPfest I just made up)
Kind of off tangent but there seems a bit of an uptick lately in - it's only a matter of time until we get a detection. I was just pondering..signal detection or evidence. N weapons give off a gamma double flash right that must be detectable for a light year or two. So maybe we made ourselves detectable. Do we not in war convert a LOT of mass to energy if you get me? I was musing on the chances of our first detection being signs of conflict out there, we might faff about with a few radio signals but surely it's the H BOMB that made us locally detectable? Signs of war and conflict. It would be deliciously cool and terrifying if it was a - yep, that was definitely aliens testing out a Nicol Dyson Beam on a planet.
We will be long dead before we have answers. We screwed up. Maybe the future evolutions of other animal species will be able to learn from us, if we can store data that long.
What is its just the tip of some galactic shrapnel from the destruction of Alderaan !! another billion voices all silenced at once. C'mooon Betelgeuse go boom before I die. Thanks for another great video.
If interstellar space is highly populated with non-trivial objects like these, that pretty much kyboshes any hope of interstellar travel for us in the future.
If our solar system is moving through an effective 'sea' of interstellar objects, what does that say about human interstellar travel. Rocky road indeed.
Man, the audio quality on Dr. Jewitt's microphone is just painful. Literally, my ears hurt after listening to this interview. Was there nothing that could be done in post, to reduce the god-awful sibilance?
loool it wasn't that bad, but I get the commentary cuz that's usually how I feel when you have guests outside of the controlled studio setting if you want to hear from the guests you just have to live with it tho cuz they are prob not gonna have a yeti or w/e and studio set up maybe by biggest nitpick, and I'm just speaking generally, is when the levels are so different that 1 is quiet and 1 is loud
@@frasercain yeah, I'm not an audio engineer, but there's really only so much you can do, I think, when guests are actual academics and not like professional pod guests I'd rather hear from them at zoom call quality than not at all tho
