Yes, it is much better than conjecture. The article does a poor job of describing the evidence and theory involved. The theory is based on a wide range of data and modeling of the solar wind and the interstellar medium. If you really want to learn more about it I suggest you search astro-ph on heliosphere (http://xxx.lanl.gov/find/astro-ph) -- here's one good paper to read: http://xxx.lanl.gov/pdf/astro-ph/0606324. Or at least read the wikipedia article on the heliosphere.
In fact the heliosphere is bow-shaped as has been understood for some time. The "dent" mentioned is a departure from the roundish shape of the bow shock in the upwind direction -- really asymmetry is a better description. And its based partly on when the two Voyagers crossed the solar wind termination shock and partly on the direction from which particles were detected as Voyager 2 approached the shock.
Slashdot Mirror
Yes, it is much better than conjecture. The article does a poor job of describing the evidence and theory involved. The theory is based on a wide range of data and modeling of the solar wind and the interstellar medium. If you really want to learn more about it I suggest you search astro-ph on heliosphere (http://xxx.lanl.gov/find/astro-ph) -- here's one good paper to read: http://xxx.lanl.gov/pdf/astro-ph/0606324. Or at least read the wikipedia article on the heliosphere. In fact the heliosphere is bow-shaped as has been understood for some time. The "dent" mentioned is a departure from the roundish shape of the bow shock in the upwind direction -- really asymmetry is a better description. And its based partly on when the two Voyagers crossed the solar wind termination shock and partly on the direction from which particles were detected as Voyager 2 approached the shock.