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I'm aware of Where does the Solar System end? but this question is different because I'd like to focus on the specific announcement by NASA about the Voyager spacecraft "leaving the solar system".

How can Voyager 1 have left the Solar System if there are comets and other trans-Neptunian objects much further away, which orbit the Sun and which therefore are part of the Solar System? It seems deceptive to me that they keep making this claim.

NASA has made this claim here: August 2012 - Voyager 1 Left the Solar System.

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    $\begingroup$ Who are "they"? From solarsystem.nasa.gov/missions/voyager-1/in-depth The spacecraft finally exited the heliosphere and began measuring the interstellar environment on Aug. 25, 2012, the first spacecraft to do so. [...] However, if we define our solar system as the Sun and everything that primarily orbits the Sun, Voyager 1 will remain within the confines of the solar system until it emerges from the Oort cloud in another 14,000 to 28,000 years. $\endgroup$
    – PM 2Ring
    May 22, 2021 at 12:46
  • $\begingroup$ You should make that an answer, @PM2Ring. $\endgroup$
    – David Hammen
    May 22, 2021 at 13:47
  • $\begingroup$ As your question notes, it depends on how you define the "edge of solar system" And this question doesn't have a single "answer". I think you'll find the a good and detailed explanation of the various meaning of the edge of the solar system at the linked question and answer. It doesn't say if you find it deceptive or not, that is your judgement. $\endgroup$
    – James K
    May 22, 2021 at 14:00
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    $\begingroup$ Voting to leave open because the proposed duplicate is a helpful but different question and answers there do not actually address this question directly, which asks how can Voyager have "left the solar system" while at the same time there are objects much farther that are still part of the solar system. $\endgroup$
    – uhoh
    May 22, 2021 at 23:58
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    $\begingroup$ NASA has indeed made this claim, I included a source in the OP. $\endgroup$
    – Some Student
    May 23, 2021 at 10:08

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It's a fair question!

How can Voyager 1 have left the Solar System if there are comets and other trans-Neptunian objects much further away, which orbit the Sun and which therefore are part of the Solar System?

Where does the Solar System end? is a start, but there is more going on here.

NASA says this because they define leaving the Solar System as TWO conditions being true at the same time:

  1. It has left the heliosphere and is now experiencing interstellar space. Before, Voyager was surrounded by cozy and familiar solar wind, but after passing through the bow shock the plasma particles around it now are interstellar in origin. It has left the harbor and is now out to sea.
  2. It is not gravitationally bound to the Sun. It is moving faster than escape velocity so it will never return.

There are indeed (probably) objects much farther than the Voyagers that are in interstellar space, but they are still well-bound to the Sun and part of our solar system for that reason.

It seems deceptive to me that they keep making this claim.

Hopefully it won't seem that way any longer. :-)

heliopause

Source

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The Voyager missions have enough energy to escape the suns gravity, i.e. their velocity is larger than the local escape velocity. That is not the case for anything orbiting the sun.

This is neither deceptive nor bombastic, it's classical mechanics 101.

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