But-But-Wait! Voyager 1 Has NOT Left the Solar System!

[stromboli]

https://medium.com/the-physics-arxiv-blog/6911d42443b

On 12 September 2013, NASA announced that the Voyager 1 spacecraft had entered a new region of space. The density of plasma in this region is much higher than is possible in the Solar System but about the level expected in interstellar space. So the probe must have finally left the Solar System, they said.

The news was greeted with the sound of champagne corks popping. But the celebrations may be have been premature. It turns out the evidence that Voyager 1 is beyond the Solar System isn't quite as ironclad as NASA suggested.

Today Nathan Schwadron and David McComas at the Southwest Research Institute in Texas say that NASA's conclusion doesn't add up. They point out that while the plasma density has increased dramatically, the direction of the magnetic field in that region of space hasn't changed at all.

That's a problem because although astronomers have never directly measured the interstellar magnetic field, they're pretty sure it must be significantly different from the Sun's field which dominates inside the Solar System.

So what gives? Schwadron and McComas have a fascinating suggestion. They say Voyager 1 may be caught in a kind of magnetic portal known as an interstellar flux transfer event.

This occurs when the magnetic fields from two different objects briefly become connected through a tube-like magnetic structure. Exactly this process happens between the Earth and Sun's magnetic field every eight minutes or so. It would be no surprise if similar flux transfer events take place regularly between the Sun's field and the interstellar field.

An interstellar flux transfer event would explain both the increase in plasma density and the absence of change in the magnetic field. That's because the magnetic tube that connects the Sun's field with the interstellar field would allow particles from outside to enter the Solar System. That would increase the plasma density without changing the magnetic field.

"If this were the case, Voyager 1 remains inside the heliopause," say Schwadron and McComas. So the spacecraft may not have left the Solar System just yet.

There is still reason to celebrate, however. If Schwadron and McComas are correct, the properties of this magnetic portal can give them crucial data about the interstellar magnetic field. "Based on the Voyager 1 observations we can determine the polarity of the interstellar magnetic field for the first time," they say. For those interested, the interstellar
magnetic field runs ?, ?) ~ (40°, -38°) in ecliptic coordinates.

There's an interesting detective story here. Space scientists have been watching Voyager approach the edge of the Solar System for a decade or so. Now the spacecraft is finding it hard to let go.

Interstellar Flux Transfer Event? Well, shut my mouth!  :-D

I swear, this puppy's more indecisive than a teenage girl in a sweater boutique. The defunding of NASA has got to be part of the reason.

[PopeyesPappy]

The Southwest Research Institute, or SwRI as they are affectionately known, is my subcontractor on my project here in Corpus Christi. I guess I'm going to have to smack em around a little for contradicting my previous post on the subject.

[stromboli]

The Southwest Research Institute, or SwRI as they are affectionately known, is my subcontractor on my project here in Corpus Christi. I guess I'm going to have to smack em around a little for contradicting my previous post on the subject.

Yup. Saw that one coming.  :-D

[PopeyesPappy]

SwRI is an impressive organization. About 3000 employees. Most of them engineers and professionals. Almost $600M in revenue annually. Then have a 1200 acre facility just inside the loop on the northwest side of San Antonio with over 2,000,000 square feet of office and research space.

[Hydra009]

I swear, this puppy's more indecisive than a teenage girl in a sweater boutique.

Yeah.  It's really all semantics at this point.  I mean, it's >125 AUs away.  That's pretty damn far.  Far enough for a steep reduction in solar wind near the probe.  While there is no exact edge to the solar system, the probe is close enough for a mulligan, imo.

[josephpalazzo]

I had to revise my chart... #-o