Is our solar system native to the Milky Way

Wolfshadw

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Hey all,

I've had this idea bouncing around in my head for a few months now and I'm wondering what your thoughts might be.

From our observations, we think that our solar system does not stay within the galactic plane, but seems to fluctuation above and below the plane. Do all stars in the galaxy do this or is it just our own, or perhaps just those closest to us?

My thinking is that our solar system was originally part of a dwarf galaxy that collided with the Milky Way 2 bya. and this is what accounts for our fluctuation around the galactic plane.

I don't know. What do you guys/gals think?

-Wolf sends
 
May 8, 2020
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Hey all,

I've had this idea bouncing around in my head for a few months now and I'm wondering what your thoughts might be.

From our observations, we think that our solar system does not stay within the galactic plane, but seems to fluctuation above and below the plane. Do all stars in the galaxy do this or is it just our own, or perhaps just those closest to us?

My thinking is that our solar system was originally part of a dwarf galaxy that collided with the Milky Way 2 bya. and this is what accounts for our fluctuation around the galactic plane.

I don't know. What do you guys/gals think?

-Wolf sends

Hmmm, I don't think so. I like to think our solar system was formed like every other natural solar system. Would be interesting if our solar system, and many others possibly, were originally part of a dwarf galaxy. By the way, do think we'll ever get to met other life, assuming there is. Sometimes it is fun to imagine shooting stars as alien spacecraft.
 
Oct 23, 2019
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It would be surprising if the sun did not stray a bit from the galactic plane. Not all stars would have formed exactly in the galactic plane, and all such stars ( the majority in any galaxy) would naturally have an orbit that fluctuates above and below the galactic plane. Also the Milky Way itself is warped, probably to mergers with other galaxies in the past, events that could also warp the orbit of stars in the galaxy.
 
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FYI, if you use software like Starry Night Pro Plus 8, SkySafari, Stellarium 0.20.1, each object has its own galactic latitude and longitude assigned. For example, tonight we have Venus galactic coordinates but these are not the same as the star Vega or Arcturus galactic coordinates. Those galactic coordinates change and a simulation showing the changes with the passage of time is needed. In astrometry I prefer a cross check too that supports such extrapolations, e.g. star observations from millions of years ago - something we do not have :) Wolfshadw said "My thinking is that our solar system was originally part of a dwarf galaxy that collided with the Milky Way 2 bya" This model would need to explain the radiometric ages of the meteorites said to cluster about 4.56 billion years ago and show the galactic coordinate changes for the solar system in 2 billion years time span that will be different than the present galactic coordinates say for the planet Venus or Earth.
 

Catastrophe

"Science begets knowledge, opinion ignorance.
Hmmm, I don't think so. I like to think our solar system was formed like every other natural solar system. Would be interesting if our solar system, and many others possibly, were originally part of a dwarf galaxy. By the way, do think we'll ever get to met other life, assuming there is. Sometimes it is fun to imagine shooting stars as alien spacecraft.
"Sometimes it is fun to imagine shooting stars as alien spacecraft."

Oh! Come on! Seeing our friendly Universal Compatriots burning up in the atmosphere is fun? ;)
 
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The Sun’s velocity components

U positive in the direction of the Galactic Center

V positive in the direction of galactic rotation

W positive in the direction of the North Galactic Pole

(U, V, W) = (11.1, 12.24, 7.25) km/s

These values are incorrect and do not give the Sun enough velocity to produce an elliptical orbit above the galactic plane. The “dolphin” orbit is an attempt to create an orbit from bad starting parameters. The absolute velocity (with usable accuracy) can be determined from microwave measurements of Milky Way structures. I have no idea why these numbers were reported as factual.

Kepler is not good enough for galaxies?
 
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"Kepler is not good enough for galaxies?" my answer is no. Since 1933 when Zwicky started reporting observations suggesting dark matter, spiral galaxy rotation curves do not match Kepler orbits like we see in our solar system. Mercury is faster and Pluto moves slower. Spiral galaxy rotation curves indicate stars, gas, etc. are moving similar velocities from near their centers to outer arms. This is well documented like Vera Rubin studies, etc. Modeling the Sun's original galactic coordinate position using the system in use today like you see in Stellarium or Starry Night software (galactic latitude and galactic longitude coordinates), I have not seen extrapolated back at least 4.5 billion years to show where the Sun was then based upon the radiometric ages of meteorites accepted and compared to the present galactic coordinates used for the Sun. The Sun needs to complete at least 18 revolutions or rotations around the Milky Way center in some 4.5 billion years.
 
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Geomartian comments about the Sun's LSR measurements and solar reflex velocity is correct (220 km/s). See these reports, Local standard of rest based on Gaia DR2 catalog, Determination of the local standard of rest using the LSS-GAC DR1, Constraining the Solar Galactic Reflex Velocity using Gaia Observations of the Sagittarius Stream

My observation, using a = 8 kpc for the Sun's distance from galaxy center, e=0.06, the period of orbit or revolution is 223.21E+8 years with average orbital velocity 220 km/s. In 4.5E+9 years, the Sun in theory could complete 20.16 galactic rotations about the center extrapolated using the LSR values today and the solar reflex velocity determined (about 229 km/s in some reports, others about 220 km/s). The upper and lower limits for the Sun's U, V, W velocity parameters I do not have extrapolated over 4.5 billion years for the Sun's motion, likewise "...measure the solar reflex velocity, and thereby infer the velocity of the Local Standard of Rest (LSR),.." that may be about 229 km/s today.

So as originally stated in this thread, "My thinking is that our solar system was originally part of a dwarf galaxy that collided with the Milky Way 2 bya." Is there the U, V, W measurements and velocity of the LSR for the Sun (solar reflex velocity), 2 billion years ago documented in astronomy? My answer is no.

In my opinion, this indicates that we do not know firmly and securely, that the Sun has been moving in the galaxy for the time period derived using radiometric ages of meteorites documented since 1956 by Clair Patterson work or the 2 billion year time span reference here for the solar system coming from a dwarf galaxy that collided with the Milky Way.