Oh no! Another alien probe

[The Valkyrie]

This can't have been a real alien probe.

If it were and it's already heading away from Earth, there would be someone appearing in the media from Hicksville, USA, claiming he was abducted and now has a really sore bum!

[Anomalocaris]

That that makes it impossible for such an object to form elsewhere?

No.  It's just unusual given the immense volume of space for there to be interstellar interlopers.  Clearly, much more scientific study is needed.

It may actually not be that uncommon.  Some estimate suggest several interstellar object with diameter on the order of sevrral meter passes through the solar system inside the orbit of the earth every year.

It's just that objects that small traveling in hypobolic orbits are difficult to detect even if they come through the inner solar system, and resources have not been devoted to systematically searching for them.

There have been visual meteors which streaked through the earth's atmosphere at apparent speeds suggestive of hyperbolic velocity and extra-solar origin. But photographic proof establishing definitively their atmospheric entry speed is lacking, which is required to prove their original orbital essentricity.

This object is much larger, and can be detected much further away than an one meter object.  It happen to reach detection threshold while we have instruments pointed in its direction.  The operator happen to be interested in finding comets and asteroids,  this object so happen to sufficiently resemble a small comet or asteroid for the operator to take a second and then a third look. if it weren't for these coincidences, it would have gone zooming off without us being any the wiser.    Had it not been found within a few month of when we actually found it, even Hubble pointed in exactly the right direction would not have seen it.

[Fireball]

It's such a big sky, and us with such small telescopes, unable to collect all the electromagnetic radiation from DC to light. Shit is going to form and come from every direction, including retrograde to our solar system's spin, and even out of the plane of the ecliptic.

[Jehanne]

It's such a big sky, and us with such small telescopes, unable to collect all the electromagnetic radiation from DC to light. Shit is going to form and come from every direction, including retrograde to our solar system's spin, and even out of the plane of the ecliptic.

I would agree, as long as Newtonian physics is not violated.  If an object forms around its parent star, then it's stuck there, unless, by some chance, that object acquires enough kinetic energy to escape its star.  Such occurrences are very atypical.

[Anomalocaris]

Actually, ejecting small objects from stellar systems is dynamically much easier than you might think.

Certainly if the object started in a circular orbit deep inside the star's gravitational well, say where the major planets in our solar system are, it would take one hell of an energy boost to kick the object out of the system.   But if the layout of our solar system is any guide, in terms of numbers, but not mass, the vast majority of discrete objects that orbits the sun orbits in an very extended Oort cloud hundreds to thousands of times further from the sun than the farthest major planet.   They are near the edge of the sun's gravity well to start with and are very loosely bound by the sun's gravity. The dekta V required to boost them into a hyperbolic trajectory could be just a few dozen meters per second.   These objects require only a small influence on their orbital speed, say gravitational purtrbation of a star that passes with 1-2 light years,  to get either sent them into the inner solar system, or ejecting completely out of the solar system.

As an order of magnitude estimate, you might say approximately for every comet that was sent into the inner solar system for us to see and catalogue, another was ejected from our solar system by the same event that sent the comet we catalogue in from the Oort cloud.

So even today, our solar system is probably still shedding objects similar to the one we detected into interstellar space In spurts with each relatively close encounter with nearby stsrs, or even rogue interstellar planets, which averages out to an long term average rate of at least several, possibly up to several hundred comets shed, a year.

There are probably still somewhere between a trillion and quadrillion meter sized object or above in the port cloud. So our sun won't run out of comets to shed into interstelar space during the remaining life of the sun.

[Jehanne]

Absolutely true, but the object in question was devoid of any coma, which is to be expected if it formed far from its parent star.

[Anomalocaris]

True enough.  But the steady leakage of distant Oort comets may dominate mass loss from solar system today, but that may not always have been the case.

Jupiter accounts for over half of all the mass that orbits the sun, as well as over two thirds of the all the total angular momentum there is in the entire solar system, the sun included.   Gravitational sling shot with Jupiter is capable of ejecting objects out of the solar system by itself.   Several Nasa spacecraft takes advantage of this to boost themselves into escape trajectories from solar system.

Today Jupiter does not account for significant number of ejections from solar system because the Jupiter  has already largely cleared out the band around its own orbit, so there is nothing for Jupiter to eject.

However, during the first 500 million years of solar system's life, both Jupiter and Saturn's orbits were unstable under each other's gravitational influence.   Jupiter and SatuBo's orbits migrated quite a bit. During this period, the inner solar system still had a lot more small objects remaining from the initial accretion of planets.  Any comets in the inner solar system would over several million years have their volatile booked off and leave behind an cinder that would be indistinguishableb from an asteroid, just like our object.   In the early solar system, As Jupiter and Saturn's orbits migrated , they  would sweep  broad swath of the inner solar system clean of these objects.   A sizeable portion of those swept by Jupiter would have been sling shot out of the solar system by Jupiter's gravity.

Brcause total mass and density of objects in the inner solar system during early part of solar system history was likely much higher than in the oort cloud today,   the total number of baked inner solar system objects slung shot by Jupiter out of the solar system during the period of orbit migration in the first 500million years of solar system history may well account for a sizeable fraction of all the objects ever dispersed by the solar system into interstellar space.

[Gawdzilla Sama]

That that makes it impossible for such an object to form elsewhere?

No.  It's just unusual given the immense volume of space for there to be interstellar interlopers.  Clearly, much more scientific study is needed.

Lots of people are claiming that the stellar inception is the only way such would form. "Visitor from another star!" Tedious.

[Jehanne]

No.  It's just unusual given the immense volume of space for there to be interstellar interlopers.  Clearly, much more scientific study is needed.

Lots of people are claiming that the stellar inception is the only way such would form. "Visitor from another star!" Tedious.

I am not claiming that it was an alien spaceship, only that such is not an absurd possibility. More data is needed.

[Anomalocaris]

Also, take a rough average of the distance between main sequence stars in the neighborhood of our solar system of about 4 lights.  Each star would have to itself a volumn of space equal to about 10e38 cubic kilometers.  

Solar system currently still has roughly a quadrillion comets orbiting it in the extended Oort cloud.  It is believed the Oort cloud originally included many times more objects and extended much closer to the inner solar system.  Much of the deficit were swept up or scattered by the gravity of the major planets, primarily Jupiter and Saturn.  Most of these collided with planets, the sun, or were through into an inner keeper belt.  But a sizeable portion, probably at least equal to the number still remaining in the Oort cloud,  were ejected from solar system altogether and scattered into the interstellar space.   Say the solar system sent 1 quadrillion objects into interstellar space over its life.

Divide the average volumn of interstellar space per main sequence star, by the average number of objects each main sequence star disperse into interstellar space, take the cube root, we arrive at the average distance separation between interstellar objects.

It turns out due to the enormous number of objects, the separation is not that great, about 90 million Kms. So this means on average, in a sphere of space with a radius equal to the orbit of the earth, there should be around 10 interstellar objects at any given time.

Of course most objects are likely to be small, meter sized or less.

If heliopause defines solar system, then at this very moment, there are probably on the order of a million interstellar objects 1 meter across or bigger inside the heliopause.