Solar System's Edge Redefined

I find this stuff weirdly fascinating.

Solar System's Edge Redefined

I guess I don't understand why discovering one new orbiting body "redefines the edge of the solar system" whereas the thousands of known comets, with elliptical orbits that center on the sun, do not.

Also, the idea of a large unseen planet beyond the Oort belt is slightly ridiculous. Gravity out there wouldn't be strong enough for a capture. There's a reason the rocky planets are close in, the gas giants further out, and everything beyond that is frozen ice balls.

Speaking of ccomets.

First pic: Rosetta comet-chaser tears through space after its icy prey

I still define the edge of the solar system the same way most people do: "Way the fuck out there!"

I thought the edge should be where solar and gravitational influence (i.e. sphere of influence) ceases. The long gone Voyager probes, at least one of them, have traversed this SOI into interstellar space.

wiki wrote:

In August 2009 Voyager 1 was over 16.5 terameters (16.5×1012 meters, or 16.5×109 km, 110.7 AU, or 10.2 billion miles) from the Sun, and thus had entered the heliosheath region between the solar wind's termination shock and the heliopause (the limit of the solar wind). Beyond the heliopause is the bow shock of the interstellar medium, beyond which the probes enter interstellar space and the Sun's gravitational influence on them is exceeded by that of the Milky Way galaxy in general. At the heliopause, light from the Sun takes over 16 hours to reach the probe.

Once the influence of interstellar medium meets and exceeds our star's infleuence, that seems to me to be the reasonable edge/boundary of our solar system.

SAI2 wrote:

Once the influence of interstellar medium meets and exceeds our star's infleuence, that seems to me to be the reasonable edge/boundary of our solar system.

IOW, "way the fuck out there."

The influence of gravity and solar wind never diminishes to zero, but it gets pretty weak at 16lh.