<p>It's a fair question!</p>
<blockquote>
<p>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?</p>
</blockquote>
<p><a href="https://astronomy.stackexchange.com/q/6519/7982">Where does the Solar System end?</a> is a start, but there is more going on here.</p>
<h3>NASA says this because they define leaving the Solar System as TWO conditions being true at the same time:</h3>
<ol>
<li>It has left the <a href="https://en.wikipedia.org/wiki/Heliosphere#Heliopause" rel="nofollow noreferrer">heliosphere</a> 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 <em>left the harbor and is now out to sea.</em></li>
<li>It is not gravitationally bound to the Sun. It is moving faster than escape velocity so it will never return.</li>
</ol>
<p>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.</p>
<blockquote>
<p>It seems deceptive to me that they keep making this claim.</p>
</blockquote>
<p>Hopefully it won't seem that way any longer. :-)</p>
<p><a href="https://i.sstatic.net/NS64A.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/NS64A.jpg" alt="heliopause" /></a></p>
<p><a href="https://commons.wikimedia.org/wiki/File:PIA17046_-_Voyager_1_Goes_Interstellar.jpg" rel="nofollow noreferrer">Source</a></p>

CC BY-SA 4.0
2021-05-22T13:48:46.557Z
2021-05-23T00:02:55.553Z
2021-05-23T00:02:55.553Z
uhoh
<p>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.</p>
<p>This is neither deceptive nor bombastic, it's classical mechanics 101.</p>

CC BY-SA 4.0
2021-05-22T13:39:10.373Z
2021-05-22T13:39:10.373Z
AtmosphericPrisonEscape
<p>I'm aware of <a href="https://astronomy.stackexchange.com/q/6519/7982">Where does the Solar System end?</a> but this question is different because I'd like to focus on the specific announcement by NASA about the Voyager spacecraft &quot;leaving the solar system&quot;.</p>
<p>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.</p>
<p>NASA has made this claim here: <a href="https://www.nasa.gov/directorates/heo/scan/images/history/August2012_2.html" rel="nofollow noreferrer">August 2012 - Voyager 1 Left the Solar System</a>.</p>

CC BY-SA 4.0
2021-06-12T01:19:14.160Z
I've added a clarifying statement at the beginning differentiating this question from the previously proposed duplicate and **voted to reopen**. I think this is a good question and can have further answers.
uhoh
CC BY-SA 4.0
2021-06-12T21:09:25.107Z
The "announcement" is rather a (poorly written) image caption. The actual press releases linked under the caption are pretty clear about what interstellar means. They never use the ambiguous wording "left the solar system", only the caption does. I would not call that an "announcement" or a "claim": voting to leave closed.
Jean-Marie Prival
CC BY-SA 4.0
2021-05-22T12:46:09.240Z
Who are "they"? From https://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.
PM 2Ring
CC BY-SA 4.0
2021-05-22T13:47:54.187Z
You should make that an answer, @PM2Ring.
David Hammen
CC BY-SA 4.0
2021-05-22T14:00:30.713Z
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.
James K
CC BY-SA 4.0
2021-05-22T23:58:31.237Z
**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.
uhoh
CC BY-SA 4.0
2021-05-23T07:44:28.120Z
Voting to close because the OP failed to show that such claim was made and by whom... Instead, the first comment makes it pretty clear that Nasa does not make this claim. So the question is based on false premise.
Jean-Marie Prival
CC BY-SA 4.0
2021-05-23T10:08:48.940Z
NASA has indeed made this claim, I included a source in the OP.
Some Student
<solar-system><nasa>
How can Voyager have left the solar system while at the same time there are solar system objects much farther?
Some Student
# How can Voyager have left the solar system while at the same time there are solar system objects much farther?

(Asked by: username_0 on 2021-05-22)

I'm aware of [Where does the Solar System end?](https://astronomy.stackexchange.com/q/6519/7982) 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](https://www.nasa.gov/directorates/heo/scan/images/history/August2012_2.html).

**Tags:** solar-system, nasa
> **Comments:**
> **username_3**: Who are "they"? From https://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.  
> **username_4**: You should make that an answer, @PM2Ring.  
> **username_5**: 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.  
> **username_1**: **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.  
> **username_2**: Voting to close because the OP failed to show that such claim was made and by whom... Instead, the first comment makes it pretty clear that Nasa does not make this claim. So the question is based on false premise.  
> **username_0**: NASA has indeed made this claim, I included a source in the OP.  
> **username_1**: I've added a clarifying statement at the beginning differentiating this question from the previously proposed duplicate and **voted to reopen**. I think this is a good question and can have further answers.  
> **username_2**: The "announcement" is rather a (poorly written) image caption. The actual press releases linked under the caption are pretty clear about what interstellar means. They never use the ambiguous wording "left the solar system", only the caption does. I would not call that an "announcement" or a "claim": voting to leave closed.  

---

## 2 answers

### Answer by username_1 on 2021-05-22. Score: 4

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?](https://astronomy.stackexchange.com/q/6519/7982) 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](https://en.wikipedia.org/wiki/Heliosphere#Heliopause) 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](https://i.sstatic.net/NS64A.jpg)](https://i.sstatic.net/NS64A.jpg)

[Source](https://commons.wikimedia.org/wiki/File:PIA17046_-_Voyager_1_Goes_Interstellar.jpg)


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### Answer by username_6 on 2021-05-22. Score: 1

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.


---

