<p>I'm not sure there are very clear official definitions, but here is my take on accepted usage in the star formation community:</p>

<p><strong>Outflows</strong> - general term describing both winds and jets.</p>

<p><strong>Jets</strong> - collimated outflows along magnetic poles.</p>

<p><strong>Winds</strong> - outflow from the stellar surface in all directions, not just along the poles.</p>

<p>Stellar winds are what comes from individual bright stars. Jets can be protostellar jets from young stars, or on a larger scale from galactic nuclei.</p>

CC BY-SA 4.0
2018-09-11T13:57:29.937Z
2018-09-11T13:57:29.937Z
FJC
<p>For jets, I found a pdf file <a href="http://www.mpia.de/homes/fendt/Lehre/Lecture_JETS/lect_jets3.pdf" rel="nofollow noreferrer">here</a></p>

<blockquote>
  <p>Jet: collimated beam of matter of high velocity</p>
  
  <p>sources: young stars, active galactic nuclei, $\mu$-quasars, gamma­ ray bursts, planetary nebulae, pulsars</p>
  
  <p>jet sources host accretion disks</p>
</blockquote>

<p><strong>How about winds and outflows?</strong> Can somebody make some clarifications for the <strong>three</strong> concepts， their <strong>correlation and difference</strong>?</p>

CC BY-SA 4.0
2018-09-11T12:49:20.147Z
Wind is usually a stellar wind, i.e. an isotropic flux of charged particles emitted by a start (the sun also ejects a wind). A jet is produced by the system of accretion disc + protostar and is a highly collimated and very fast beam of ionized matter ejected in a bi-polar fashion. This jet collides with the (dense and neutral) ambient medium and accelerates those gas particles. They form an outflow (often bi-polar, and much less collimated) and are visible in emission of the accelerated gas, usually CO,
Markus Roellig
CC BY-SA 4.0
2018-09-11T13:02:40.607Z
@Roellig so both wind and jet are outflows? A disk is not necessary for wind, right?
questionhang
CC BY-SA 4.0
2018-09-12T11:21:40.853Z
Right. No need for a disk to produce winds.
Markus Roellig
<astrophysics>
What is the difference between wind, jet and outflow?
questionhang
# What is the difference between wind, jet and outflow?

(Asked by: username_0 on 2018-09-11)

For jets, I found a pdf file [here](http://www.mpia.de/homes/fendt/Lehre/Lecture_JETS/lect_jets3.pdf)

> Jet: collimated beam of matter of high velocity
>
> sources: young stars, active galactic nuclei, $\mu$-quasars, gamma­ ray bursts, planetary nebulae, pulsars
>
> jet sources host accretion disks

**How about winds and outflows?** Can somebody make some clarifications for the **three** concepts， their **correlation and difference**?

**Tags:** astrophysics

> **Comments:**
> **username_1**: Wind is usually a stellar wind, i.e. an isotropic flux of charged particles emitted by a start (the sun also ejects a wind). A jet is produced by the system of accretion disc + protostar and is a highly collimated and very fast beam of ionized matter ejected in a bi-polar fashion. This jet collides with the (dense and neutral) ambient medium and accelerates those gas particles. They form an outflow (often bi-polar, and much less collimated) and are visible in emission of the accelerated gas, usually CO,  
> **username_0**: @username_1 so both wind and jet are outflows? A disk is not necessary for wind, right?  
> **username_1**: Right. No need for a disk to produce winds.  

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## 1 answers

### Answer by username_2 on 2018-09-11. Score: 2 | Accepted answer

I'm not sure there are very clear official definitions, but here is my take on accepted usage in the star formation community:

**Outflows** - general term describing both winds and jets.

**Jets** - collimated outflows along magnetic poles.

**Winds** - outflow from the stellar surface in all directions, not just along the poles.

Stellar winds are what comes from individual bright stars. Jets can be protostellar jets from young stars, or on a larger scale from galactic nuclei.


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