Solar,
In my October 2016 post I wrote:
Robertus Maximus wrote:The Heliosphere and the Solar Cycle
The long accepted view of the shape of the heliosphere (HS) is that it is a comet-like object with a long tail opposite to the direction in which the solar system moves through the local interstellar medium (LISM). However, in the paper by Parker (The Stellar Wind Regions, 1961) we find from figure 1 (in the original paper) that the comet-like shape occurs under certain conditions namely: ‘The streamlines of the subsonic, nearly incompressible, hydrodynamic flow of a stellar wind beyond the shock transition (r=R) in the presence of a subsonic interstellar wind
carrying no significant magnetic field.’ Indeed, Parker described the special condition under which a comet-like shaped HS would occur:
‘Steady subsonic interstellar wind without interstellar magnetic field’. (1) (my emphasis).
Parker, however, did model a HS constrained by a: ‘Large scale interstellar field in the absence of significant interstellar gas pressure and interstellar wind’, only this HS is not comet-like.
So, the accepted model of the HS is one based on the assumption that there is no significant LISMF. But we now know that there must exist a significant magnetic field, coupled with a slower relative inflow motion we can ask- would a comet-like HS form at all?
In this paper: ‘Imaging the Interaction of the Heliosphere with the Interstellar Medium from Saturn with Cassini’ by S. M. Krimigis, et al. 2009, the authors suggest, following a review of data from the Cassini spacecraft and based on the morphology of the ‘Cassini Belt’, that the HS is indeed shaped as Parker described, if it were influenced by a: ‘
Large scale interstellar field in the absence of significant interstellar gas pressure and interstellar wind’ and not the conventional comet-like shape, the authors admit that: ‘It is very different from the contemporary paradigm.’ (2)
To my mind a picture is emerging that is at odds with the mainstream view of the HS.
Standard interpretation of the alignment of the Heliosphere
Looking at an all-sky map we find that the ‘nose’ of the comet-like HS lies at a point between the constellations Ophiuchus and Scorpius, in the general direction of the galactic centre (0 degrees, galactic longitude). On the same map we find
Voyager 1also lies within the constellation Ophiuchus whilst
Voyager 2 can be found in the constellation Telescopium. Viewed from Earth both Voyager spacecraft are headed ‘upwind’ in the ‘nose’ of the HS (the HS ‘tail’ can be found ‘downwind’ in the constellation of Taurus, 180 degrees galactic longitude).
Viewed from Earth
Voyager 2 is remarkably close to the structure known as the IBEX Ribbon. Is it possible that one or both of the Voyager spacecraft have measured conditions in the outer HS influenced by the IBEX Ribbon? Furthermore, if the ‘comet-like’ HS model is wrong, as observations of the Cassini Belt suggest, where would that leave the Voyager spacecraft and what are they measuring?
From the alternative model i.e. a ‘diamagnetic bubble’ suggested by Krimigis, et al. and for the purpose of this discussion I will use the term ‘Heliotube’ (HT) to describe the nature of the environment from which the Sun draws energy to sustain the solar discharge.
- Galactic Coordinates looking toward 270 degrees longitude. For illustrative purposes only, not to scale.
- Galactic Coordinates looking toward 0 degrees longitude. For illustrative purposes only, not to scale.
From the illustrations above it can be seen that the ‘X’ of the pinched HT approximately matches the latitudinal extent of both the Heliospheric Current Sheet (HCS) and Cassini Belt.
Now, how does this relate to the findings of Dialynas et al? Let us consider the standard interpretation of the heliosphere’s interaction with the VLISM, this view was accepted for over five decades and was based on the comet-like model suggested by Parker.
In this model the two Voyager spacecraft are heading “upwind” in the “nose” direction of the comet-like shaped heliosphere- we now know this model is incorrect.
With the galactic coordinate system in mind: (
https://upload.wikimedia.org/wikipedia/ ... estial.png), looking at an all-sky map based on galactic coordinates: (
http://www.atlasoftheuniverse.com/wgalchart.gif), and paraphrasing what I wrote earlier, we see that “the “nose”’ of the comet-like heliosphere lies at a point between the constellations Ophiuchus and Scorpius, in the general direction of the galactic centre (0 degrees, galactic longitude). On the same map we find
Voyager 1 also lies within the constellation Ophiuchus whilst
Voyager 2 can be found in the constellation Telescopium. Viewed from Earth both Voyager spacecraft are headed “upwind”’ in the “nose” of the heliosphere (the heliosphere “tail” can be found “downwind” in the constellation of Taurus, 180 degrees galactic longitude).
Conventionally, both Voyager spacecraft and
Pioneer 11 are heading in the general direction of the galactic centre (0 degrees galactic longitude) toward the “nose”, only
Pioneer 10 is heading in the direction of the “tail” (180 degrees galactic longitude).
However, we know that the solar system is moving in a direction not quite perpendicular to the galactic centre (approximately 70 degrees galactic longitude) from the constellation of Canis Major toward the constellation Lyra.
With the comet-like heliosphere model in mind, why is the VLISM flow from the general direction of the galactic centre?
Now, let us consider the diamagnetic bubble model (originally suggested by Parker) as revealed by Voyager and
Cassini observations.
(
https://www.nature.com/article-assets/n ... 115-f1.jpg)
From the image in the link above, we see a bubble shaped heliosphere with the “Interstellar flow” (red lines) still arriving from the “nose” direction, where we find the two Voyager spacecraft but now if we look at the “Interstellar magnetic field” (grey lines), the alignment of the field-lines is not too dissimilar to the orientation of the “Heliotube”, i.e. not quite perpendicular to the line of 0 degrees galactic longitude) with the long axis aligned along the plane of the galaxy.
If, I am correct, then why are researchers still talking in terms of “nose” and “tail”, why is the inflow reportedly from the “nose”? Obviously this terminology would be a relic from the comet-like model, nevertheless in the Heliotube model inflow would occur in the waist or pinched region of the Heliotube creating the impression of a “nose”.
The IBEX Ribbon, which was visible at solar minimum 2009- 2010, is found toward the “nose” hemisphere, if you refer to my 2D image from my October 2016 post looking towards 0 degrees galactic longitude, where I have shown this. In a 3D representation I would visualise this as a pinched red Coca Cola can the IBEX Ribbon represented by the white “flow” motif.
What of the “tail”? I was sceptical with the claims made by researchers when they looked at the “tail” region, to a certain extent I believe they were seeing a tail when one just simply was not there. The “tail” hemisphere of the heliosphere is simply a region where the off-set IBEX Ribbon was incomplete. At the beginning of the
IBEX mission, the Ribbon flux portrayed latitudinal and energy-dependent ordering related to the FSW-SSW structure. In the last few years, however, this ordering has broken down, reflecting solar maximum conditions.
The latest
IBEX data release and paper can be found here:
http://ibex.swri.edu/ibexpublicdata/Dat ... index.html
The authors conclude: “… that the solar wind must be the ultimate source of the Ribbon ENAs.” As I have repeatedly pointed out on this thread the heliosphere and the Sun itself, show asymmetrical behaviour the authors agree “…the heliosphere’s interaction is highly asymmetric and not well described by simple symmetric models.”
IBEX has observed solar minimum and maximum conditions (although an unusual weak maximum) it will be interesting to see how the outer heliosphere and VLISM continue to evolve as a new cycle begins.
Now, from my point of view, my mind still at odds with the mainstream view, or perhaps it is just odd?