Starship Asterisk*

Sa Ji Tario wrote: ↑Wed Jun 23, 2021 3:21 am
Terrible, do not forget that when bodies with gravity appear, so do the Lagrange points
and the planets can be prior to the primaries

• Trojan minor planets & moons... but few actual stable co-orbital exoplanets:

https://en.wikipedia.org/wiki/Co-orbital_configuration#Trojan_planets wrote:
<<Trojan objects orbit 60° ahead of (L4) or behind (L5) a more massive object, both in orbit around an even more massive central object. The best known example are the asteroids that orbit ahead of or behind Jupiter around the Sun. Trojan objects do not orbit exactly at one of either Lagrangian points, but do remain relatively close to it, appearing to slowly orbit it. In technical terms, they librate around ( Δ λ , Δ ϖ ) = (±60°, ±60°). The point around which they librate is the same, irrespective of their mass or orbital eccentricity.
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Trojan minor planets: There are several thousand known trojan minor planets orbiting the Sun. Most of these orbit near Jupiter's Lagrangian points, the traditional Jupiter trojans. As of 2015 there are also 13 Neptune trojans, 7 Mars trojans, 2 Uranus trojans (2011 QF99 and 2014 YX49) and 1 Earth trojan (2010 TK7) known to exist.
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Trojan moons: The Saturnian system contains two sets of trojan moons. Both Tethys and Dione have two trojan moons each, Telesto and Calypso in Tethys's L4 and L5 respectively, and Helene and Polydeuces in Dione's L4 and L5 respectively.

Polydeuces is noticeable for its wide libration: it wanders as far as ±30° from its Lagrangian point and ±2% from its mean orbital radius, along a tadpole orbit in 790 days (288 times its orbital period around Saturn, the same as Dione's).
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Trojan planets: A pair of co-orbital exoplanets was proposed to be orbiting the star Kepler-223, but this was later retracted. The possibility of a trojan planet to Kepler-91b was studied but the conclusion was that the transit-signal was a false-positive. One possibility for the habitable zone is a trojan planet of a giant planet close to its star.
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Formation of the Earth–Moon system: According to the giant impact hypothesis, the Moon formed after a collision between two co-orbital objects: Theia, thought to have had about 10% of the mass of Earth (about as massive as Mars), and the proto-Earth—whose orbits were perturbed by other planets, bringing Theia out of its trojan position and causing the collision.>>

VictorBorun wrote: ↑Tue Jun 22, 2021 11:44 pm

The jets are magnetic pigtails, right? Starting as many centrifugal-forced jets from the hotter inner part of accretion disk where magnetic lines (forming a thorus around circular electric current) are at 30° to the axis. And then the matter of many little jets stretch the magnetic lines until they wind into a pigtail, a hollow cylinder around the axis. And we are closing on that pair of pigtails, both observingly and model-tuningly.

VictorBorun wrote: ↑Tue Jun 22, 2021 11:36 pm Sagittarius, right?
I took coordinates 17 56 21.26 -21 57 21.6 from here
and entered them here

bystander wrote: ↑Tue Jun 22, 2021 2:43 pm

Dee Phlat wrote: ↑Tue Jun 22, 2021 1:37 pm
Is this jet the same as a Herbig-Haro object?

Herbig-Haro objects are shock waves formed when the high energy jets collide with the interstellar medium.

https://en.wikipedia.org/wiki/Herbig%E2%80%93Haro_object#Infrared_counterparts wrote:

HH objects are formed when accreted material is ejected by a protostar as ionized gas along the star's axis of rotation

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<<Herbig–Haro (HH) objects are bright patches of nebulosity associated with newborn stars. They are formed when narrow jets of partially ionised gas ejected by stars collide with nearby clouds of gas and dust at several hundred kilometres per second.

HH objects associated with very young stars or very massive protostars are often hidden from view at optical wavelengths by the cloud of gas and dust from which they form. The intervening material can diminish the visual magnitude by factors of tens or even hundreds at optical wavelengths. Such deeply embedded objects can only be observed at infrared or radio wavelengths, usually in the frequencies of hot molecular hydrogen or warm carbon monoxide emission. In recent years, infrared images have revealed dozens of examples of "infrared HH objects". Most look like bow waves (similar to the waves at the head of a ship), and so are usually referred to as molecular "bow shocks". The physics of infrared bow shocks can be understood in much the same way as that of HH objects, since these objects are essentially the same – supersonic shocks driven by collimated jets from the opposite poles of a protostar. It is only the conditions in the jet and surrounding cloud that are different, causing infrared emission from molecules rather than optical emission from atoms and ions. In 2009 the acronym "MHO", for Molecular Hydrogen emission-line Object, was approved for such objects, detected in near infrared, by the International Astronomical Union Working Group on Designations, and has been entered into their on-line Reference Dictionary of Nomenclature of Celestial Objects. The MHO catalog contains over 2000 objects.>>

Dee Phlat wrote: ↑Tue Jun 22, 2021 1:37 pm Is this jet the same as a Herbig-Haro object?

De58te wrote: ↑Tue Jun 22, 2021 11:45 am

shaileshs wrote: ↑Tue Jun 22, 2021 6:16 am 3 questions top of my head -

1) Why multiple disks ? Can there be 1, 2, many ? How many and depends on what ?
2) Why opposite side of jet is disjoint (floating) as if it has no connection with source (jet coming towards us seems more uniform comparitively)
3) Any idea if plane of disks is deterministic (say compared to plane of solar system or plane of galaxy etc) ? Or is completely random (un-deterministic, unpredictable) ?

Thanks in advance for all comments/thoughts/answers.

Number 2) This may be my unscientific theory, but the disc is taken by radio waves by ALMA, and the jet by visible light from VLT. That means that some technician had to combine the two images in some photo lab. Perhaps the disc should be placed further back. In addition since that is a star forming region how do we know there is behind there in the gap some dense dark cloud that hasn't begun to form yet and isn't emitting any radio waves, yet is dark enough to block the visible light heading in our direction?

shaileshs wrote: ↑Tue Jun 22, 2021 6:16 am 3 questions top of my head -

1) Why multiple disks ? Can there be 1, 2, many ? How many and depends on what ?
2) Why opposite side of jet is disjoint (floating) as if it has no connection with source (jet coming towards us seems more uniform comparitively)
3) Any idea if plane of disks is deterministic (say compared to plane of solar system or plane of galaxy etc) ? Or is completely random (un-deterministic, unpredictable) ?

Thanks in advance for all comments/thoughts/answers.