POSSIBLE Intergalactic meteor stream detected?

[MeteorWayne]

If this pans out, it's AFAIK, the first unequivocal detection of meteoroids from outside the solar system, never mind the galaxy. Note this article has been submitted, not accepted, and without the full artcle, it's hard to judge the merits of the case the authoors make.--MW<br /><br /> Detection of an intergalactic meteor particle with the 6-m telescope<br />Authors: V.L. Afanasiev (1), V.V. Kalenichenko (2), I.D. Karachentsev (1) ((1) Special Astrophysical Observatory Russian Academy of Sciences (2) Astronomical Observatory, Kyiv Taras Shevchenko University)<br />(Submitted on 10 Dec 2007)<br /><br />Abstract: On July 28, 2006 the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences recorded the spectrum of a faint meteor. We confidently identify the lines of FeI and MgI, OI, NI and molecular-nitrogen N_2 bands. The entry velocity of the meteor body into the Earth's atmosphere estimated from radial velocity is equal to 300 km/s. The body was several tens of a millimeter in size, like chondrules in carbon chondrites. The radiant of the meteor trajectory coincides with the sky position of the apex of the motion of the Solar system toward the centroid of the Local Group of galaxies. Observations of faint sporadic meteors with FAVOR TV CCD camera confirmed the radiant at a higher than 96% confidence level. We conclude that this meteor particle is likely to be of extragalactic origin. The following important questions remain open: (1) How metal-rich dust particles came to be in the extragalactic space? (2) Why are the sizes of extragalactic particles larger by two orders of magnitude (and their masses greater by six orders of magnitude) than common interstellar dust grains in our Galaxy? (3) If extragalactic dust surrounds galaxies in the form of dust (or gas-and-dust) aureoles, can such formations now be observed using other observational techniques (IR observations aboard Spitzer satellite, etc.)? (4) If inhomogeneous extragalactic dust <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[vogon13]

How many such objects have to be in the universe for this observation to have been statistically likely ??<br /><br /><br />Seems like if you do the math, the total mass might be rather large. <br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[h2ouniverse]

e.g. say four times the visible matter mass? <img src="/images/icons/wink.gif" />

 

[robnissen]

Related to this topic, I have the following questions:<br /><br />1) Does anyone here know what the escape velocity from the Andromeda galaxy is?<br /><br />2) If matter did escape from the Andromeda galaxy, would it be reasonably possible that it could be captured by the MW?<br /><br />3) Putting 1 and 2 together: How long would it take for matter to escape the Andromeda galaxy and be captured by the MW?<br /><br />Putting the three previous questions together, has there been enough time since Andromeda and MW formed for there to be a substantial (say on the order of 1 sol mass total) exchange of matter between the two galaxies?

 

[h2ouniverse]

1) huge uncertainties exist on M31 mass, once said to be larger than MW, now allegedly two thirds of MW.<br />Say it is of same OOM than MW, and that escape velocity is similar in OOM to MW. It is highly a function of distance to center. From 30000 LY of center, it is 1000 km/s in MW. <br />2) If its has been ejected from the periphery of M31, ie with lower velocities than Ve at Sun's orbit (<1000km/s), and with a trajectory passing by the Sun, the arrival velocity might be low enough for a capture<br />3) If you say relative velocity is about 500km/s, and distance M31-MW is 2.5 e6 LY= 1.6e11 AU =2.4 e19 km, time to reach us is1.5 billion years.<br />= /> answer is yes

 

[CalliArcale]

I don't have much to add except: SWEET!!!! That is so freakin' cool! <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[billslugg]

I'm lost. <br /><br />The MW escape velocity is 1000km/sec.<br />A piece of gravel hits our windshield at 300km/sec.<br /><br />Presuming there is no mechanism within the solar system to accelerate anything to 300km/sec, it must have come from outside the solar system.<br /><br />By why consider it extragalactic? <div class="Discussion_UserSignature"> <p> </p><p> </p> </div>

 

[MeteorWayne]

The paper suggests that the coincidence between our velocity toward the<br />"centroid of the Local Group" and the alleged meteoroids are significant.<br /><br />I'm still reading the full paper for the third time. Need a head icebag.<br /><br />Again, just a reminder, this is a submitted, not an accepted paper.<br />Other meteoricists have raised some questions that have to be investigated. The peer review process by the journal has not been completed. This is a work in progress.<br /><br />that's science <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[3488]

WOW this is just amazing stuff.<br /><br />This is the sort of thing that is part of us going back to the Moon.<br /><br />As I have said before, the lunar regolith is likely to hold a record of billions of years of trapped<br />particles & obviously meteoroids.<br /><br />The vast majority will be from elsewhere within the Solar System, but many <br />may be intersteller & now possibly intergalactic. <img src="/images/icons/laugh.gif" /><br /><br />Perhaps the ancient surfaces of the distant inactive moons of the outer planets, or<br />Dysnomia, Eris's moon, may be even better, as from that distnace from the sun, <br />intersteller & intergalactic particles & rogue meteoroids are less like to be <br />molested by solar radiation.<br /><br />Thank you very MeteorWayne.<br /><br />I wonder if Stardust may have some in the Aerogel?????<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[robnissen]

<font color="yellow">A piece of gravel hits our windshield at 300km/sec. </font><br /><br />Uh . . . no. It is possible that gravel could hit your windshield at 300m/sec., but that is highly unlikely because the terminal velocity of gravel will be a lot less than about 650 mph, but 650,000 mph for gravel, I don't think so.

 

[robnissen]

Thx. I appreciate the answer.

 

[billslugg]

Rob<br />Can you add some words here? I am missing your point.<br /><br />The article said the object was going at 300Km/sec when it hit the upper atmosphere. It came from the direction into which we are traveling relative to the local group. I did not 'actually' mean it hit an actual windshield. It hit us in the face so to speak. The 300km/sec is not a terminal velocity, but the velocity at the top of the atmosphere. <div class="Discussion_UserSignature"> <p> </p><p> </p> </div>

 

[thebigcat]

RobNissen: <i>Uh . . . no. It is possible that gravel could hit your windshield at 300m/sec., but that is highly unlikely because the terminal velocity of gravel will be a lot less than about 650 mph, but 650,000 mph for gravel, I don't think so. </i><br /><br />I think they were speaking figuratively, Rob. <img src="/images/icons/wink.gif" /> <div class="Discussion_UserSignature"> </div>

 

[silylene old]

<font color="yellow">The entry velocity of the meteor body into the Earth's atmosphere estimated from radial velocity is equal to 300 km/s.</font><br /><br />That's 0.001c. Was this the fastest meteor ever measured which hit Earth?<br /><br />While this seems fast, let's put it into perspective....<br /><br />The Andromeda galaxy is 2.57M light years away. Assuming a constant velocity of 300 km/sec, it would take 2.53 x 10^9 years for this piece of gravel to travers this distance. Or put it another way, 2.53 <i>billion</i> years to travel from galaxy-to-galaxy.<br /><br />Assuming that this piece of gravel had to be formed within a galaxy (highly certain!), and the piece of gravel had to be hurled out of the gravitational well of a galaxy by a very dense gravitational object (black hole or neutron star...again likely, since a close encounter with a regular star would have burned it up), and that this piece of gravel had to have been formed late in the age of the universe since it is metal rich, then it had to escape a nearby galaxy approximately some 2 - 5 B years ago.<br /><br />The Andromeda galaxy is closest, and metal rich, and has many black holes and neutron stars, so is the likeliest point origin. The Magellenic Clouds are poor candidates for an origin since they contain old aged (less metal-rich) stars, and not as many black holes or neutron stars, and are recent interlopers into our near-galactic space anyways.<br /><br />So now let's assume that the gravel piece did originate in the Andromeda galaxy , some 2.7 M ly away. Likely a metal-rich asteroid had a very close pass to a neutron star or black hole, got disrupted into billions of pieces of gravel, and most of those pieces of gravel were hurled at high speed out of Andromeda's gravity well. Assume these billions of gravel pieces got hurled out of Andormeda's gravity well in all random directions, and one of them heads to Earth. And then one of these gravel pieces just by random chance happened t <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[MeteorWayne]

Just to give a little more detail.<br />While so far I have not judged the validity of their claims (I'm reading the submitted paper for the 3rd time, hurting my brain, and it has not been accepted for publication yet), they also allegedly detected 12 other meteoroids with the same path and velocity. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[silylene old]

In that case, as I stated above, an entire asteroid would have had to been hurled from a nearby metal-rich galaxy 2.5B to 5B years ago (Andromeda is by far the best candidate) - somehow without being disrupted- , and by lucky vector right into our solar system, and then this asteroid would have had to have somehow this time undergone tidal disruption into a gravel stream via a close pass to the Sun (?), Jupiter or some other large planetary body, without being consumed or colliding, and get directed on an exact vector to Earth's night side, and then be detected via a highly coincidental observation that evening. Also note that this meteor stream at 300 km/s is moving too fast to remain within the solar system, so this is a one-time chance event observation.<br /><br />Uh huh. My bogameter is flashing orange.<br /><br />If I get time, I will read the paper, and also wait for criticism from experts. Until then put me in the 'highly skeptical category'. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[MeteorWayne]

I'll make room for you next to the campfire <img src="/images/icons/smile.gif" /><br /><br />I found the spectra used for calculating the 300 km/sec unconvincing, and their assignment of 12 sporadics to the same stream filled with some assumptions.<br /><br />But like I said, it will take multiple reads to absorb the whole thing.<br /><br />It would be far easier to accept the concept of meteoroids being extrasolar rather than extragalactic.<br /><br />MeteorWayne <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[robnissen]

Uh ... brain lock.<br /><br />Note to self: in the future carefully read the post before responding.

 

[h2ouniverse]

Hi Silylene,<br /><br />just as devil's advocate (for the sake of contradiction), about probability:<br /> I get the impression that any object ejected with just few hundreds of km/s from M31 more or less towards MW (over tesn od degrees) would be focused by MW's grav field and tend to actually intersect MW. The Sun is well placed as it is more or less between M31 and the center of MW<br />Btw, here they do not speak exactly of M31 but of the direction of motion of MW relatively to the local cluster. <br /><br />NB: Are we so sure that no object can condensate and differentiate far from a galaxy? Isn't it possible for clouds of very cold residual gas to coalesce into small objects? (with mostly solid hydrogen)<br /><br />Regards.

 

[silylene old]

<font color="yellow">NB: Are we so sure that no object can condensate and differentiate far from a galaxy? Isn't it possible for clouds of very cold residual gas to coalesce into small objects? (with mostly solid hydrogen) </font><br /><br />The pebbles, according to the Russian observers, is rich in heavy atoms and metals:' FeI and MgI, OI, NI and molecular-nitrogen'. Such elements are nearly non-existant in inter-galactic space. As you said, perhaps you could find a little bit of hydrogen there....but that's it.<br /><br /><font color="yellow">Btw, here they do not speak exactly of M31 but of the direction of motion of MW relatively to the local cluster.</font><br />However, as I mentioned, because the pebbles are high metal and heavy atom content, we know that they could not have formed early in the universe's age. Heavy atoms are nearly entirely synthesized by supernovas, re-condensation of the expelled gas clouds back into a next-generation star, supernova, re-condensation back into a next generation star, etc. A pebble rich in metals had to have been formed relatively recently, not 8 or 10 or 13 B yrs ago.<br /><br />So then you look at what galaxies are close enough to the MW that can be reached in, say, 5B years or less at 300 km/s. Andromeda is a great candidate. It has black holes and neutron stars which could conceivably eject an asteroid towards the MW. The other large galaxies of the local cluster are farther away, and/or have fewer good dense neutron stars and blck holes to eject an asteroid towards us. <br /><br />I do agree with you, once the putative extra-galactic asteroid gets captured within the MW's gravity well, it will be significantly more likely to be on a vector to intersect the MW. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[h2ouniverse]

Galaxies when absorbed by another one tend to generate filaments of matter that stay around for a while. Isn't it possible IYO that such a small filament is involved there? (probabilty low, unless such remnant filaments overstretch before/during capture)

 

[MeteorWayne]

That's actually a much more reasonable idea than that it came from the local cluster. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[silylene old]

The putative extra-galactic asteroid would still have to have been ejected from its original solar system somehow. But I agree, this is easier than ejecting from a distant galaxy and then traveling billions of years to encounter the MW. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[sssalvi]

I am not an astronomer... but came across this news. Don't know whether it is the same stuff that you are talking.<br /><br />Indian and German astronomers have jointly discovered, completely by chance, a 1.5 million light year-long intergalactic beam, the longest to be ever found. <br /><br />link : http://timesofindia.indiatimes.com/articleshow/2607565.cms

 

[richalex]

It isn't. But, it is interesting.