APOD: A/2017 U1: An Interstellar Visitor (2017 Nov 03)

[BDanielMayfield]

Someone is hurling stones at us.

This theory can be discounted due to the inaccuracy of the aim.

Bruce

[neufer]

Someone is hurling stones at us.

This theory can be discounted due to the inaccuracy of the aim.

• Unless that someone is now blind.

[b][color=#0000FF]Blinded Polyphemus enraged, hurls rocks at Odysseus's ship.[/color][/b]

---

<<But when we were no further away [out at sea] than a man's voice, I called to the Kyklopes and taunted him : ‘Kyklops, your prisoner after all was to prove not quite defenceless--the man whose friends you devoured so brutally in your cave. No, your sins were to find you out. You felt no shame to devour your guests in your own home; hence the requital from Zeus and the other gods.’

Rage rose up in him at my words. He wrenched away the top of a towering crag and hurled it in front of our dark-prowed ship. The sea surged up as the rock fell into it; the swell from beyond came washing back at once and the wave carried the ship landwards and drove it towards the strand. But I myself seized a long pole and pushed the ship out and away again, moving my head and signing to my companions urgently to pull at their oars and escape destruction; so they threw themselves forward and rowed hard. But when we were twice as far out on the water as before, I made ready to hail the Kyklops again, though my friends around me, this side and that, used all persuasion to restrain me : ‘Headstrong man, why need you provoke this savage further? The stone he threw out to sea just now dashed the ship back to the shore again, and we thought we were dead men already. Had he heard any sound, any words from us, he would have hurled yet another jagged rock and shattered our heads and the boat's timbers, so vast his reach is.’>>

[ET 2017]

Space probe disguised as a rock!

[neufer]

Click to play embedded YouTube video.

Space probe disguised as a rock!

[hamilton1]

Apparently this object can expect to travel several quadrillion years before encountering another star at such close proximity. Does sound a bit suspicious...

[Boomer12k]

I appreciate your effort, Art. It's hard to understand the relative and absolute motions of each object when all I have to go on is a short animation. Your car chase image would probably be more useful as an analogy if I had any clue what it was about.

Watch "Bullitt" 1968 movie with Steve McQueen... one of the COOLEST car chases... then you will understand...

We are lucky for Jupiter, and the Sun... taking care of things before something big HITS us....

:---[===] *

[Boomer12k]

I have written a song....

" I am a happy wondering ISO... I go from star to star... I am searching for the one I love, I wonder where you are... something, ummmm... something....." OK, not finished but you can tell it's going to be a BIG HIT...I was a 3rd year Music Major.... I got this...

:---[===] *

[neufer]

Apparently this object can expect to travel several quadrillion years before
encountering another star at such close proximity. Does sound a bit suspicious...

Yes...this object is totally clueless about what might happen to it.

[oldwierdgeek]

I appreciate your effort, Art.
It's hard to understand the relative and absolute motions of each object when all I have to go on is a short animation.

Click to play embedded YouTube video.

The important thing is that the Sun, Vega, the asteroid and the local neighborhood are all moving along more or less together within the galactic disk at about 220 km/s.

Should we every have an Interstellar Visitor coming in at ~200 km/s (e.g., a 12 gauge shotgun round)
then we might start talking about it being an Intergalactic disk Visitor as well.

Your car chase image would probably be more useful as an analogy if I had any clue what it was about.

Sorry, but a 12-gauge shotgun's muzzle velocity is around 1200 feet/sec (just over Mach 1) or roughly 400 m/sec, not km/sec. Ditto any other gauge shotgun.

[neufer]

Sorry, but a 12-gauge shotgun's muzzle velocity is around 1200 feet/sec (just over Mach 1) or roughly 400 m/sec, not km/sec.

I'm sorry that the Bullit (analogy) went over your head.

[Meldok]

This event look like, to one of the biggest opportunity, of our History.
His trajectory prove this object coming to outside of our solar system.
What we dont know, at this time; it is only a lost asteroid or a artificiel object.
To observe this object, the time factor, is important. This phenomenou is coming and they leave our solar system. We need to optimize the observations time of the differents instruments. It is not the optimize time, for exemple; for the optic instruments, to look this object is near the sun. If the object pass to the front the sun, the sun observation satellite can probably look the detail of the forme of the object and possible degasage signature to the object. And, I suppose to have a optimum time for using a radio telescope.
This possible campagne of observations, are probably determine with a sufficient resolution the look a global forme of this object. It is looks; at our solar system asteroid like potato or are look a regular, geometrical shape of a possible artficial object. After this, it is possible to determine to some precision the diametre of the object. And to apply the law of physic to determine his mass. All of data; the diameter, the mass, we can find the density of the object. This density are important to determine the nature of his material. It is not the same density to the object made in ice, asteroid rock, must gas content space craft or must metal object.
More the data we have, to build a basic consensus. We determine to send or not; a basic SETI message in direction of this interstellar trajectory object...
This obsevation are possible find the most important breakthrough of the History or a basic fact of interstellar object...
Richard

[rstevenson]

This event look like, to one of the biggest opportunity, of our History.
His trajectory prove this object coming to outside of our solar system.
What we dont know, at this time; it is only a lost asteroid or a artificiel object.
...
Richard

The simplest way to determine that an incoming object is artificial would be to observe it changing velocity in a way that would be impossible for a 'natural' object. It could, for example, attempt to adjust its trajectory to use the Sun's gravity for a braking maneuver. Or, if braking was impossible, it might adjust its trajectory to pass close to any source of EM radiation while emitting an unambiguous signal, so as to at least attract attention to itself and hence its senders. But it seems the object just blew through on a normal falling trajectory. That doesn't completely rule out the possibility that it was an artifact of another culture, but it strongly suggests that.

Rob

[Meldok]

This type of possible interstellar travel need a better knowledge to the gravity and orbital mecanic, to we have.
And, if, the possible intelligent forme, look to don't attract our attention. They are only, to take a trajectory correction before they come in our interior solar system, without modification of trajectory near the sun...

[hamilton1]

The simplest way to determine that an incoming object is artificial would be to observe it changing velocity in a way that would be impossible for a 'natural' object. It could, for example, attempt to adjust its trajectory to use the Sun's gravity for a braking maneuver. Or, if braking was impossible, it might adjust its trajectory to pass close to any source of EM radiation while emitting an unambiguous signal, so as to at least attract attention to itself and hence its senders. But it seems the object just blew through on a normal falling trajectory. That doesn't completely rule out the possibility that it was an artifact of another culture, but it strongly suggests that.

You seem to be assuming that the object would still be under some sort of control, but there's no way of proving that assumption. After all, if Voyager passed by a distant star in the far future, it would behave exactly like a natural object. The only definite from this discovery is that there must be a gargantuan amount of these objects out there, whether they are rocks or probes:)

[rstevenson]

The simplest way to determine that an incoming object is artificial would be to observe it changing velocity in a way that would be impossible for a 'natural' object. It could, for example, attempt to adjust its trajectory to use the Sun's gravity for a braking maneuver. Or, if braking was impossible, it might adjust its trajectory to pass close to any source of EM radiation while emitting an unambiguous signal, so as to at least attract attention to itself and hence its senders. But it seems the object just blew through on a normal falling trajectory. That doesn't completely rule out the possibility that it was an artifact of another culture, but it strongly suggests that.

You seem to be assuming that the object would still be under some sort of control, but there's no way of proving that assumption. After all, if Voyager passed by a distant star in the far future, it would behave exactly like a natural object. The only definite from this discovery is that there must be a gargantuan amount of these objects out there, whether they are rocks or probes:)

Yes, I was assuming any such ship would be able to control its trajectory. Comparisons to Voyager are not appropriate. We did not send them to other stellar systems, though they may pass near them by chance at some distant point in the future.

Rob

PS
I don't, in fact, harbour any illusions as to the type of object that just passed through our solar system. The odds are very great that it was just a rock. But it's interesting to consider what to look for, so we can recognize a non-rock if one ever comes our way.

[Buddy]

Someone is hurling stones at us.

Given our current state of readiness, would we have any recourse if this thing were on a collision course with Earth? It's going really fast, and since momentum is mv², it would be packing a punch!

[SeedsofEarth]

Just wondering: since the Oort cloud theoretically surrounds the sun somewhere near the edge of the heliopause, could it possibly be that this "visitor" was simply knocked loose by a collision with another icy body from its orbit in the Oort cloud above the plane of the ecliptic, and after many thousands of years (or hundreds?) it has made its way to the inner solar system. Is the assumptiuon that it is an alien comet or asteroid based solely on its velocity?

[BDanielMayfield]

Just wondering: since the Oort cloud theoretically surrounds the sun somewhere near the edge of the heliopause, could it possibly be that this "visitor" was simply knocked loose by a collision with another icy body from its orbit in the Oort cloud above the plane of the ecliptic, and after many thousands of years (or hundreds?) it has made its way to the inner solar system. Is the assumptiuon that it is an alien comet or asteroid based solely on its velocity?

Not an unreasonable question, but objects way out in the Oort cloud will have very low velocities relative to the Sun. I suppose it might be possible for a collision to knock an Oort cloud member into a hyperbolic trajectory, but if it was from our Oort cloud it should behave and look like an icy comet, which it doesn't. Also, if it had suffered a relatively recent collision one side of it would likely be brighter than the other. This object appears to have come from another system's inner solar system where rocky bodies would be common.

Bruce