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Scientists also detected a meteor particle that appears to have been extragalactic, with a 300km/s (671,081mph) entry velocity…in 2007!
A leisurely 6% of C!
0.1 % of c ( 300,000 km/sec or 186,000 miles/sec)
What is still bloody incredible. That would be a rotation around planet Earth every 2,2 minutes. Or make it to the Moon in 21 minutes.
0.1%. Speed of light is “299792458 metres per second (approximately 300000 km/s or 186000 mi/s)” (https://en.wikipedia.org/wiki/Speed_of_light)
Interestingly, the database contains two other objects detected with impact speeds of more than 40km/s including one from 2015-07-04 which an even greater speed than this interstellar asteroid. I wonder why these are not also considered to have interstellar origin? Is it because they were accelerated by the sun before colliding with the Earth? The original paper does not mention whether or not they considered the origins of any other objects from the database.
Direction of travel can make a big difference. If it impacts one side of the earth, the leading side in the earths orbit around the sun, then you need to subtract the earth's orbital velocity. On the opposite side, you need to add earth's velocity to get a true representation of the object's speed around the sun. The earth is also spinning. The atmosphere is moving at basically the same speed as earth's rotation. That too has to be accommodated based on the direction and latitude of the impact.
Lastly, something that this paper doesn't address. There is a chance that the object was local to our solar system but had been 'flung' out onto an escape trajectory. Our solar system is a giant multi-body problem. Things can be flung out into space. This rock might have been accelerated to escape velocity by our moon or some other body. So rather than an interstellar object, it may have been a local rock on its way out that just happened to hit earth before leaving the solar system.
Good point about the relative speed of the earth. That could probably explain why the other objects turn out to be more ordinary.
As for the idea that this 2014 object originated in our solar system: I don't think that's possible. They were able to project it's incoming trajectory and there were no significant masses that could have directed it path from anywhere other than interstellar space. This is pretty clear from the paper.
Real answer:
I absolutely love being alive right now. A Higgs boson! Confirmed objects from outside our solar system! A real life picture of a black hole! We’re just at the start of being able to learn these things, and it’s getting better by the year. I love it.
Conspiracy answer:
The alien probe launched 10,000 years ago just determined that either:
1) Our atmosphere is sufficiently thick to cause the object to disintegrate over seconds instead of instantaneously, meaning there’s enough raw gaseous material to be interesting, or
2) We have an active defense system, meaning the local inhabitants are smart enough to be interesting.
In 46 years, when the light reaches its origin around 26 Draconis, observations will be recorded, reports will be filed, and plans will be made.
Sending probes is dangerous. You never know who is going to capture it and figure out where it was sent from. Conclusion: make deniable self-destructing probes.
1. Send probe to star system slow enough to be random interstellar rock on a collision course with planetary body,
2. it collects data as it approaches body,
3. then have it self-destruct in the atmo destroying all technology and information in the probe. Use the energy from the destruction to send a message back on a wide cone that can be intercepted.
> In 46 years, when the light reaches its origin around 26 Draconis, observations will be recorded, reports will be filed, and plans will be made.
This gives me Douglas Adams vibes, thinking about an alien species posting plans to invade Earth. "The plans were on display for months" [1]
[1]: https://www.goodreads.com/quotes/40705-but-the-plans-were-on...
Could you imagine trying to aim something at a moving planet from light years away and while also shooting it at that speed and not having potential a huge number of things affect it's trajectory via gravity? I love the conspiracy theory, but unless it could course-correct during flight, the odds seem insanely low for it to be a alien test probe
A civilization advanced enough to launch interstellar probes and make plans on a 20k year timescale (10k years for the probe to get here, 10k years for them to get here) has no use whatsoever for the paltry resources in our solar system. Instead they could just harvest them from nearby systems or “empty” space.
Sadly the Draconis civilization was obliterated 10 years ago, by a Supernova way too close to their planetary system. Lucky Earth Inners dodge another cosmic bullet.
(2) is more fun, and so I will actively entertain it while accepting that (1) is more likely to be true.
The fact that an interstellar object happened by chance to intersect the earth implies that there are millions of such objects flying through the solar system. Most of them probably fly through and are never seen again. We really need to get better at space operations, so we can either catch one of these objects for further study, or at least figure out a way to build a probe that could follow it out of the system.
The solar system is huge, and earth is really really tiny. For this to have happened means that it is likely to happen again, which suggests that there is a large amount of crap out there blazing through interstellar space, any sufficiently large piece of which could be a civilization-ending projectile.
We need better detection and defenses. And another planet. ASAP.
Why was this classified in the first place?
From the linked-to Vice article at https://www.vice.com/en/article/dyp9ez/secret-government-inf...
> Some of the sensors that detect fireballs are operated by the U.S. Department of Defense, which uses the same technologies to monitor the skies for nuclear detonations. As a result, Siraj and Loeb couldn’t directly confirm the margin of error on the fireball’s velocity.
So ʻOumuamua was actually the sail, the real probe arriving in 2014? #joke
I sincerely do not understand the interest of the army to hide the presence of such a small meteorite.
It's not about the meteor, it's about the capacity to detect and track it.
So the fact that they release this now means that they have an even better detection and tracking mechanism? Or do they just want others to believe that?
Wow that’s actually incredible. The first confirmed interstellar object impacted earths atmosphere? Really shows how far tech must have come in detecting these events in the last 20 years or so.
Also the coincidence of it impacting earth and not Jupiter or any other planetary body or just wizzing by is blowing my mind. Of course we have more sensors around earth so that makes sense but still. I would have thought we would’ve seen something similar to Oumououa prior to this.
If (presumed) single protons can be considered "objects" there's also the "oh-my-God particle" of 1991.
Geologist didn't have many sensors for locating earthquakes, but then several governments became very interested in tracking any nuclear testing and those sames sensors are quite good at tracking earthquakes. So much so that earthquakes can now be tracked in 3D anywhere on the planet, even enough to identify the shape and thickness of the various continental plates.
>The first confirmed interstellar object impacted earths atmosphere?
That's mostly just because we don't notice 1.5ft wide rocks in space unless they do something interesting like hit our atmosphere
> The object, a small meteorite measuring just 1.5 feet (0.45 meter) across, slammed into Earth's atmosphere on Jan. 8, 2014, after traveling through space at more than 130,000 mph (210,000 km/h)
Can anyone say what percentage of the speed of light that is?
~%0.02 the speed of light. So less one in five thousandth the speed of light.
About 0.02%
You can.
130,000 /
Speed of light: 670,616,629mph
= 0.00019385144% the speed of light
>The possibility of getting the first piece of interstellar material[...]
It's very likely that there's interstellar material already on earth from before we were able to detect the impact though, right? Question for the astrophysicists, is there something in the composition of objects that can tell us if something is interstellar in origin?
> is there something in the composition of objects that can tell us if something is interstellar in origin?
Share of isotopes.
- Isotopic analyze at Earth begins countdown from Sun system events, but events on other stars have other timeline and their star also will have other share.
Sun is not rare star, but our neighbors stars mostly different.
Plus, some of material appear from Novas and Supernovas (it is very like fingerprint of nuke - highly depend on technology available at place where it built and from raw materials from which it built), and it will also be different for thing traveled from other star.
Only problem, is that large part of this technology is classified, so scientists will have problems on every step, and some things will be opened to all only in few decades.
I'm not an astrophysicist, but from what I can gather we want these potential shards off the sea floor for analysis precisely because we're not sure what the makeup of interstellar debris would look like. It would be hard to form a criteria for suspected extrasolar material with such little data at this point.
Is the probability of this event not equal to zero then?
The paper estimates objects of these size should hit Earth at least once per decade. The database goes back to 1988 so there might even be one or two others in there waiting to be detected.
The Arachnids are bombing Earth. (Starship Troopers)
And they outsourced the flight path planing to the G'Gugvuntts
Tiny meteorite (1.5 feet across) enters Earth's atmosphere and burns up. What is so remarkable about this? Doesn't this happen like every day?
Meteors from our own solar system impact the atmosphere every day. One estimate for the frequency of an interstellar meteor hitting Earth is about once per decade: https://www.forbes.com/sites/brucedorminey/2019/04/17/inters...
Nearly all meteorites are from the asteroid belt -- interstellar origin is the interesting thing here.
Meteorites from our solar system hit the Earth around 20-30km/h
This extrasolar thing hit the Earth at 200km/h+.
Remember that the kinetic energy formula = 0.5 * m * v²
Is the velocity squared that means something very small can still wipe out an entire city in a gigantic fireball with little to no warning and ability to do anything about it. This is a very big deal for the people looking at things like asteroid defense at civilization time scales.
The interesting aspect is "interstellar" (=from outside the solar system) instead of just "interplanetary", which would imply an origin within the solar system.
Stuff from outside is a lot rarer.
> The object, a small meteorite measuring just 1.5 feet (0.45 meter) across,
So a bit too small to hold baby Kal-El.
Except unless he's really tiny and cuddly. Like a baby hamster.
And landed in the ocean, so he'd have drowned.