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Leaving the galaxy


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NASA: Sorry, Voyager 1 Still In Solar System

 

“The Voyager team is aware of reports today that NASA’s Voyager 1 has left the solar system,” said Edward Stone, Voyager project scientist based at the California Institute of Technology, Pasadena, Calif. “It is the consensus of the Voyager science team that Voyager 1 has not yet left the solar system or reached interstellar space. In December 2012, the Voyager science team reported that Voyager 1 is within a new region called ‘the magnetic highway’ where energetic particles changed dramatically. A change in the direction of the magnetic field is the last critical indicator of reaching interstellar space and that change of direction has not yet been observed.”
 

 

 

 

Can't they not send false positives?

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Pics from voyager

http://azstarnet.com/gallery/news/science/photos-images-from-voyager-i/collection_25860074-95d4-11e2-a6cf-001a4bcf887a.html#0

 

 

So what did happen?
 
Florinski said there was a "sharp transition" from particles you would expect to find in the heliosphere, the "bubble" created by our nearest star's solar wind, to those galactic cosmic rays you'd expect to find on the other side.
 
The magnetic field is the only contraindication, he said.
 
It could be that the heliopause, the place where the magnetic fields of the two regions meet up, is not a smooth region, but a "wavy, turbulent boundary," through which Voyager is now passing, he said.
 
Or Voyager could have crossed a different boundary created by the different directions of solar winds from the sun's north and south hemispheres.
 
Or maybe, one participant suggested after the talk, those magnetic field measurements, very weak, and very open to interpretation, are not what they seem to be.
 
We weren't supposed to be having this discussion yet.
 
Scientists had originally predicted that the distance to the heliopause would be 130 to 160 astronomical units away (an AU is the average distance from the Earth to the sun) and Voyager 1 is only 123.5 AUs away.
 
Florinski had some possible explanations for that as well. The sun has been pretty low-energy in its current 11-year cycle and perhaps it's not pushing the bubble as far as it once was.
 
Or - perhaps something else.
 
As Florinski said near the beginning of his talk: "These are my interpretations, so I take full responsibility for them, and they could prove out to be wrong."

 

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that's leaving the solar system.

 

Leaving the galaxy is a much bigger challenge.

 

 

*MUCH* bigger. Escape velocity this far out in the galaxy is about 330 miles/second. Voyager 1 is now at 11 miles/second and will only slow a little bit more down in leaving the Sun's gravity well. But it's not a factor of 30 in difficulty -- the energy scales with the square. So Voyager 1 has insufficient kinetic energy by a factor of *900* to escape the galaxy.

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*MUCH* bigger. Escape velocity this far out in the galaxy is about 330 miles/second. Voyager 1 is now at 11 miles/second and will only slow a little bit more down in leaving the Sun's gravity well. But it's not a factor of 30 in difficulty -- the energy scales with the square. So Voyager 1 has insufficient kinetic energy by a factor of *900* to escape the galaxy.

 

Oh no!  We are all prisoners in our own galaxy!   :lol:

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Wasn't dark matter suppose be on the rim of our solar system??

Yet theres an experiment on the ISS that might be able to detect it

and yet the expensive large hyrdron collider could not recreate or detect it,

 

Wasn't the Dark Matter suppose to slow voyager exit of the solar system but there isn't anything out there?

very puzzling?? can any one clarify?

lol, I don't think I can reiterate my physics brothers significant talk but he thinks nothing is slowing voyager as of yet by much.

 

Tantalizing New Clues Into the Mysteries of Dark Matter

 

The dark side of the universe is whispering, but scientists are still not sure what it is saying.
 
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Samuel Ting, a professor at the Massachusetts Institute of Technology and a Nobel laureate particle physicist, said Wednesday that his $1.6 billion cosmic ray experiment on the International Space Station had found evidence of  “new physical phenomena” that could represent dark matter, the mysterious stuff that serves as the gravitational foundation for galaxies and whose identification would rewrite some of the laws of physics.
 
The results, he said, confirmed previous reports that local interstellar space is crackling with an unexplained abundance of high energy particles, especially positrons, the antimatter version of the familiar electrons that comprise electricity and chemistry. They could be colliding particles of dark matter. Or they could be could be coming from previously undiscovered pulsars or other astronomical monsters, throwing off wild winds of radiation.
 
The tantalizing news is that even with the new data, physicists cannot tell yet which is the right answer, but they are encouraged that they soon might be able to.

 


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hh5: Dark matter is spread smoothly through galaxies, we know that because stars orbiting a galaxy measure its mass, and there's a lot more mass than the stars and gas account for. It presumably permeates our whole solar system, even our Earth, and our bodies. But it doesn't interact --- much.

 

The Alpha Magnetic Spectrometer on the space station is far too small to detect dark matter directly, because of the proven rarity of interactions. Much larger volumes of mass have been instrumented deep under the Earth (including deep under the antarctic ice in a cube a kilometer on a side) to look for such interactions directly.

 

Instead, the AMS looks (among other things) for positrons, a type of antimatter, produced by one possible type of dark matter interaction, which would produce electron-positron pairs. Electrons are everywhere and common, but positrons are pretty rare, as antimatter in a matter-dominated universe. Many things can create small populations of positrons, though, so interpreting a positron signal from the AMS is difficult. Is it "excess" to what is expected? What is expected? You have to consider the trajectories of incoming positrons at different energies and try to figure out how many can be made by different mechanisms and how many survive to reach low Earth orbit.

 

The Large Hadron Collider can in no way make this measurement because positrons cannot penetrate the atmosphere -- they are annihilated very very high up through encounters with ordinary electrons. It generates its own debris (including lots of positrons) through collisions, but these are not signatures of a cosmic production process.

 

Since Dark Matter is uniformly distributed on the scale of the solar system it should play no role in the local deceleration of Voyager. If such a deceleration were found, it would indicate that gravity behaved somewhat differently at small than at large scales - or that dark matter indeed tended to clump somewhat around solar-sized masses. So people look carefully. The force of gravity has now been measured on scales as short as 0.06 millimeter (University of Washington) and they are working on still shorter tests. So far, it's the good ol' inverse square law.

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speed of 42.1 km/s is required to escape the Sun's gravity (and exit the Solar System)

Can you imagine how much space garbage collecting at the edge of the solar system

if we try to send more probes out of the solar system?

 

we already got a lot of orbital garbage around the earth

 

Oh no!  We are all prisoners in our own galaxy!   :lol:

Edited by hh5
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There IS a lot of garbage out there, it seems humans can't resist leaving their junk where ever they go.  I think there's litter on the moon and mars too, and probably on a few other planets.  It seems to me we aren't making a very good first impression on whoever might be living there.  You know, as many UFO's and little space men who've been spotted on earth, none of them seem to have left their garbage laying around.  We need to learn from their example, and stop trashing things up.  They might be more willing to talk to us if we respected their space more.

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  • 2 weeks later...

oh how lucky V1 n 2 didn't encounter any dark matter

... it be scary to discover how many wimps are out there vs seeking out heavenly bodies

 

Dark matter detector reports hints of WIMPs

 

There IS a lot of garbage out there, it seems humans can't resist leaving their junk where ever they go.  I think there's litter on the moon and mars too, and probably on a few other planets.  It seems to me we aren't making a very good first impression on whoever might be living there.  You know, as many UFO's and little space men who've been spotted on earth, none of them seem to have left their garbage laying around.  We need to learn from their example, and stop trashing things up.  They might be more willing to talk to us if we respected their space more.

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  • 4 months later...

Voyager left solar system last year, new research shows

Reuters) - NASA's long-lived Voyager probe crossed into interstellar space last year, becoming the first man-made object to leave the solar system, new research shows.
 
Scientists have been waiting for Voyager to detect a magnetic field that flows in a different direction than the solar system's magnetic field. But the new research shows that scenario is not accurate.
 
"We think that the magnetic field within the solar system and in the interstellar are aligned enough that you can actually pass through without seeing a huge change in direction," University of Maryland physicist Marc Swisdak said in an interview with Reuters on Thursday.
 
That would mean that Voyager actually reached interstellar space last summer when it detected a sudden drop in the number of particles coming from the sun and a corresponding rise in the number of galactic cosmic rays coming from interstellar space.
 
Not everyone is convinced, however.
 
Voyager lead scientist Edward Stone, now retired from NASA's Jet Propulsion Laboratory in Pasadena, California, said Swisdak's research is interesting but different computer models are portraying different scenarios to explain the Voyager data.
 
"We know where Voyager is in terms of distance and we know what it is observing. The challenge is relating that to these complex models of the interaction between the interstellar medium and the heliosphere," Stone said, referring to the bubble of space that falls under the sun's influence.

 

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