First, I'd like to point out I was surprised someone would insist on the researchers' model which almost certainly is doing N-body simulations/Monte Carlo models. These Monte's have been for, what is it now? several decades?, been controversial because their results are highly dependent on initial conditions, or at the very least consistently yield black holes as causative,
or binary system interactions.
Studies I found today have found ..
3 of the 4 Trapezium central stars are .. binaries, or greater.
My interpretation of the desire to ok the black hole explanation has something to do with, shall we say, "salesmanship" of black holes, kind of like paleobiology's dinosaurs being another hot topic people are interested in. I'm going to hunt down the referenced Charles U. study. But I'm going to put this reference up now because it by itself should clear all doubt, and note it comes
Nowhere near utilization of black holes as cause of data. And the authors pulled the data in: Hubble, Spitzer, VLA, etc.
Here it is, note the date, and Ann, you should especially like it: do read the link
On the dynamical evolution of the Orion Trapezium
Christine. Allen,⋆ Rafael Costero, Alex Ruelas-Mayorga, L. J. Sanchez,
https://arxiv.org/pdf/1701.03440.pdf
some notable quotes from above:
13 January 2017
"Neither [of the 2 studies] attempted to use actual observed values of positions, velocities and masses of the Orion Trapezium components as initial conditions,
due to the unavailability of such data. (While admitting I haven't read the Charles U. study, it does call into question their reasoning. Have they solely used modeling inputs, no observations? and then came up with another controversial result without binaries input?)
It is clear that the region near the Orion Trapezium has been very active dynamically. Studies of the radio sources embedded in the BN-KL region (Rodr´ıguez et al. 2005, G´omez et al. 2008) showed that three of these radio sources move away from a common point where they converged about 500 years ago. Costero et al. (2008), observing only the radial velocity, found that
Component E of the Orion Trapezium is
escaping from it, probably as a result of dynamical interactions within the system.
Component B is really a mini-cluster, composed by at least 5 stars in close proximity (Close et al. 2013).
Allen et al. (2015) conducted a numerical exploration of the dynamical evolution of this mini-cluster, arriving at the conclusion that its age is probably less than 30,000 years."
A "strong, non-thermal radio source first detected by Churchwell et al. (1987)."
From its IR photometric properties and assuming it belongs to the Trapezium Cluster, the mass
of this third component was estimated to be about 4 M⊙ by Weigelt et al (1999), Shertl (2003), Grellmann et al. (2013).
For the numerical N-body integrations we used the well-tested code by Mikkola & Aarseth (1993)."
"At 100 crossing times (
about 1 million years) the dynamical evolution is practically over."
"
We can conclude that Star E probably was bound to the Orion Trapezium in the recent past, and that it escaped only about 2,000 years ago."
" .. it is highly unlikely for systems resembling the Orion Trapezium as a whole to be able to generate runaway stars, as has sometimes been claimed."
"An interesting question is whether the widely accepted notion that the Orion Trapezium is a bound system is valid, especially in view of the rather short lifetimes we find, and of the escaping Component E. At least two arguments support its being a bound system. First, the probability of finding four bright stars within a radius of 10 arcseconds is very low.
Second, the relative motions of the main components in the plane of the sky are very small, also implying a bound system. However, if a better knowledge of the radial velocities should show widely discrepant values, the question would have to be re-examined."
This is other material which suggests more of the dynamic nature of the Trapezium area in the past:
"We study the dynamical interaction in which the two single runaway stars AE Aurigae and mu Columbae and the binary iota Orionis acquired their unusually high space velocity. The two single runaways move in almost opposite directions with a velocity greater than 100 km/s away from the Trapezium cluster. The star iota Ori is an eccentric (e=0.8) binary moving with a velocity of about 10 km/s at almost right angles with respect to the two single stars. The kinematic properties of the system suggest that a strong dynamical encounter occurred in the Trapezium cluster about 2.5 Myr ago.
Curiously enough, the two binary components have similar spectral type but very different masses, indicating that their ages must be quite different. This observation leads to the hypothesis that an exchange interaction occurred in which an older star was swapped into the original iota Orionis binary. .. "
N-body simulations of stars escaping from the Orion nebula
https://arxiv.org/abs/astro-ph/0401451
"HD 37023: of the four Trapezium cluster stars this is the only one without a binary companion (Preibisch et al. 1999)."
http://www.aanda.org/articles/aa/full/2 ... 66-05.html
A "food source" for our sneaky black hole?
Theta1 Orionis C1 .. emits a powerful stellar wind that is a hundred thousand times stronger than the Sun's, and the outpouring gas moves at 1,000 km/s."
https://en.wikipedia.org/wiki/Theta1_Orionis_C
First, I'd like to point out I was surprised someone would insist on the researchers' model which almost certainly is doing N-body simulations/Monte Carlo models. These Monte's have been for, what is it now? several decades?, been controversial because their results are highly dependent on initial conditions, or at the very least consistently yield black holes as causative, [b]or binary system interactions[/b].
Studies I found today have found .. [b]3 of the 4 Trapezium central stars are .. binaries[/b], or greater.
My interpretation of the desire to ok the black hole explanation has something to do with, shall we say, "salesmanship" of black holes, kind of like paleobiology's dinosaurs being another hot topic people are interested in. I'm going to hunt down the referenced Charles U. study. But I'm going to put this reference up now because it by itself should clear all doubt, and note it comes [u]Nowhere near[/u] utilization of black holes as cause of data. And the authors pulled the data in: Hubble, Spitzer, VLA, etc.
Here it is, note the date, and Ann, you should especially like it: do read the link
[b]On the dynamical evolution of the Orion Trapezium[/b]
Christine. Allen,⋆ Rafael Costero, Alex Ruelas-Mayorga, L. J. Sanchez,
[b]https://arxiv.org/pdf/1701.03440.pdf[/b]
some notable quotes from above:
[b]13 January 2017 [/b]
"Neither [of the 2 studies] attempted to use actual observed values of positions, velocities and masses of the Orion Trapezium components as initial conditions, [b][u]due to the unavailability of such data.[/u][/b] (While admitting I haven't read the Charles U. study, it does call into question their reasoning. Have they solely used modeling inputs, no observations? and then came up with another controversial result without binaries input?)
[b]It is clear that the region near the Orion Trapezium has been very active dynamically[/b]. Studies of the radio sources embedded in the BN-KL region (Rodr´ıguez et al. 2005, G´omez et al. 2008) showed that three of these radio sources move away from a common point where they converged about 500 years ago. Costero et al. (2008), observing only the radial velocity, found that [b]Component E [/b]of the Orion Trapezium is [b]escaping[/b] from it, probably as a result of dynamical interactions within the system.
[b]Component B is really a mini-cluster, composed by at least 5 stars in close proximity [/b](Close et al. 2013).
Allen et al. (2015) conducted a numerical exploration of the dynamical evolution of this mini-cluster, arriving at the conclusion that its age is probably less than 30,000 years."
A "strong, non-thermal radio source first detected by Churchwell et al. (1987)."
From its IR photometric properties and assuming it belongs to the Trapezium Cluster, the mass
of this third component was estimated to be about 4 M⊙ by Weigelt et al (1999), Shertl (2003), Grellmann et al. (2013).
For the numerical N-body integrations we used the well-tested code by Mikkola & Aarseth (1993)."
"At 100 crossing times ([b]about 1 million years[/b]) the dynamical evolution is practically over."
"[b]We can conclude that Star E probably was bound to the Orion Trapezium in the recent past, and that it escaped only about 2,000 years ago[/b]."
" .. it is highly unlikely for systems resembling the Orion Trapezium as a whole to be able to generate runaway stars, as has sometimes been claimed."
"An interesting question is whether the widely accepted notion that the Orion Trapezium is a bound system is valid, especially in view of the rather short lifetimes we find, and of the escaping Component E. At least two arguments support its being a bound system. First, the probability of finding four bright stars within a radius of 10 arcseconds is very low.
Second, the relative motions of the main components in the plane of the sky are very small, also implying a bound system. However, if a better knowledge of the radial velocities should show widely discrepant values, the question would have to be re-examined."
This is other material which suggests more of the dynamic nature of the Trapezium area in the past:
"We study the dynamical interaction in which the two single runaway stars AE Aurigae and mu Columbae and the binary iota Orionis acquired their unusually high space velocity. The two single runaways move in almost opposite directions with a velocity greater than 100 km/s away from the Trapezium cluster. The star iota Ori is an eccentric (e=0.8) binary moving with a velocity of about 10 km/s at almost right angles with respect to the two single stars. The kinematic properties of the system suggest that a strong dynamical encounter occurred in the Trapezium cluster about 2.5 Myr ago. [b]Curiously enough, the two binary components have similar spectral type but very different masses, indicating that their ages must be quite different. This observation leads to the hypothesis that [u]an exchange interaction[/u] occurred in which an older star was swapped into the original iota Orionis binary. .. [/b]"
[b]N-body simulations of stars escaping from the Orion nebula[/b]
https://arxiv.org/abs/astro-ph/0401451
"HD 37023: of the four Trapezium cluster stars this is the only one without a binary companion (Preibisch et al. 1999)."
http://www.aanda.org/articles/aa/full/2006/10/aa3066-05/aa3066-05.html
A "food source" for our sneaky black hole? :ssmile:
Theta1 Orionis C1 .. emits a powerful stellar wind that is a hundred thousand times stronger than the Sun's, and the outpouring gas moves at 1,000 km/s."
https://en.wikipedia.org/wiki/Theta1_Orionis_C