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

Comments and questions about the APOD on the main view screen.
BDanielMayfield
Don't bring me down
Posts: 1466
Joined: Thu Aug 02, 2012 11:24 am
AKA: Bruce
Location: East Idaho

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

Postby BDanielMayfield » Fri Nov 03, 2017 4:19 pm

sillyworm2 wrote:Someone is hurling stones at us.

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

Bruce
"Happy are the peaceable ... "

User avatar
neufer
Vacationer at Tralfamadore
Posts: 14417
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

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

Postby neufer » Fri Nov 03, 2017 4:40 pm

BDanielMayfield wrote:
sillyworm2 wrote:
Someone is hurling stones at us.

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

    Unless that someone is now blind.
<<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.’
>>
Art Neuendorffer

ET 2017

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

Postby ET 2017 » Fri Nov 03, 2017 8:49 pm

Space probe disguised as a rock! :eyebrows:

User avatar
neufer
Vacationer at Tralfamadore
Posts: 14417
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

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

Postby neufer » Fri Nov 03, 2017 10:36 pm

Click to play embedded YouTube video.


ET 2017 wrote:
Space probe disguised as a rock! :eyebrows:
Art Neuendorffer

hamilton1
Ensign
Posts: 31
Joined: Mon Nov 02, 2015 12:00 pm

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

Postby hamilton1 » Fri Nov 03, 2017 11:32 pm

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

Boomer12k
:---[===] *
Posts: 2088
Joined: Sun Apr 22, 2007 12:07 am

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

Postby Boomer12k » Fri Nov 03, 2017 11:33 pm

geckzilla wrote: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
:---[===] *
Posts: 2088
Joined: Sun Apr 22, 2007 12:07 am

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

Postby Boomer12k » Sat Nov 04, 2017 12:18 am

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...

:---[===] *

User avatar
neufer
Vacationer at Tralfamadore
Posts: 14417
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

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

Postby neufer » Sat Nov 04, 2017 12:32 am

hamilton1 wrote:
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.
Art Neuendorffer

oldwierdgeek

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

Postby oldwierdgeek » Sun Nov 05, 2017 1:44 pm

neufer wrote:
geckzilla wrote:
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. :arrow:

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

geckzilla wrote:
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.
Last edited by geckzilla on Sun Nov 05, 2017 2:54 pm, edited 1 time in total.
Reason: moved reply to outside of quote boxes

User avatar
neufer
Vacationer at Tralfamadore
Posts: 14417
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

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

Postby neufer » Sun Nov 05, 2017 2:55 pm

oldwierdgeek wrote:
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.
Art Neuendorffer

Meldok
Asternaut
Posts: 2
Joined: Sun Nov 05, 2017 12:50 pm

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

Postby Meldok » Sun Nov 05, 2017 3:06 pm

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

User avatar
rstevenson
Quis custodiet ipsos custodes?
Posts: 2440
Joined: Fri Mar 28, 2008 1:24 pm
Location: Dartmouth, NS, Canada

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

Postby rstevenson » Sun Nov 05, 2017 3:38 pm

Meldok wrote: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
Asternaut
Posts: 2
Joined: Sun Nov 05, 2017 12:50 pm

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

Postby Meldok » Sun Nov 05, 2017 6:08 pm

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
Ensign
Posts: 31
Joined: Mon Nov 02, 2015 12:00 pm

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

Postby hamilton1 » Mon Nov 06, 2017 2:56 am

rstevenson wrote: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:)

User avatar
rstevenson
Quis custodiet ipsos custodes?
Posts: 2440
Joined: Fri Mar 28, 2008 1:24 pm
Location: Dartmouth, NS, Canada

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

Postby rstevenson » Mon Nov 06, 2017 7:37 pm

hamilton1 wrote:
rstevenson wrote: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
Ensign
Posts: 11
Joined: Wed Sep 10, 2014 4:15 pm

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

Postby Buddy » Tue Nov 07, 2017 1:14 am

sillyworm2 wrote: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

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

Postby SeedsofEarth » Wed Nov 15, 2017 7:48 pm

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
Don't bring me down
Posts: 1466
Joined: Thu Aug 02, 2012 11:24 am
AKA: Bruce
Location: East Idaho

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

Postby BDanielMayfield » Wed Nov 15, 2017 8:48 pm

SeedsofEarth wrote: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
"Happy are the peaceable ... "


Return to “The Bridge: Discuss an Astronomy Picture of the Day”

Who is online

Users browsing this forum: Ahrefs [Bot], CommonCrawl [Bot] and 2 guests