But not so fast. 
Before a star settles into middle age on 
the main sequence, it has to shake off 
some of its, youthful energy, in 
particular, more technically what's going 
on is that the end of. 
Collapse is accompanied by these polar 
outflows that we saw in the case of L1527 
and even more directly columnated 
High velocity jets of material being 
ejected from the poles of the star. 
So along the axis of its rotation. 
It turns out that these fulfill a very 
important part in the mechanism of 
collapse of stellar formation itself, 
because they carry off excess angular 
momentum, allowing material to accrete 
under the star from the protoplanetary 
disc. 
The exact mechanism that governs their 
creation is still being nailed down but 
we can observe them, we can observe them 
because this ejected material plows at 
high speed into the surrounding gas. 
Compressing it and heating it and then as 
a result, the material glows. 
These were first discovered and termed, 
these objects, these regions of hot 
glowing gas were termed Herbig-Haro 
objects. 
I don't know how to pronounce either of 
those names correctly. 
But it was later discovered that they 
were associated with the formation of a 
star. 
So what were considered as two 
Herbig-Haro objects turned out in the 
middle. 
To conceal nassin star these can be 
50,000, 100,000 astronomical units away 
took awhile to make sense of this and 
It we've been watching these objects for 
long enough now that we can actually 
produce a. 
Sequential year, frame a year of movies 
of their evolution. 
Here's the first Herbig-Haro object over 
eight years and you can see the jet 
expanding. 
Here's another film of another 
Herbig-Haro object and what you see here 
is that there's a structure to this jet 
that's being ejected. 
It's not a smooth jet, there are these 
clumps, they're about the size of the 
solar system to give you a scale. 
And these clumps are supposed to be 
expected to be regions where 
The ejector from one. 
rapid pulse are plowing into ejections 
from a previous pulse which tells you 
that there is a structure to this eject 
this process of ejection it's not 
completely smooth and 
What this causes in the vicinity of the 
star of course, is these huge stellar 
winds that we talked about, stars in this 
phase are low mass stars. 
At this phase of their existence are 
called, T Tauri stars, they exhibit 
irregular and rapid variability possibly 
associated, to, changes in the opacity of 
the, Dust and a clouds that still 
surround them they exhibit huge rates of 
mass loss as much as 100 millionth of a 
solar mass per year and this face can 
last for 10,000,000 years this is 
1,000,000 times the rate at which the sun 
is losing mass to the solar wind 
currently so the sun in its 10,000,000 
year tetori stage lost a lot more mass 
then it will use throughout its entire 
10,000,000,000 year main sequence career 
and this winds are directed in. 
for out from the poles but when I say 
directed out from the poles you need to 
get a scale notice that the scale of this 
internal cylinder is about astronom a 100 
astronomical units so that there is this 
outward flow in all directions. 
Out into the disk, except, at the very 
surface of the disk, the models as I said 
are not quite clear on how to model this. 
there use to be the prevailing opinion 
was at some point, that these waves are 
generated, the outflow is generated by 
the shock wave when the collapse stops, 
and there's in falling matter colliding 
with it. 
Of course as one would expect with the 
bipolar nature 
it turns out that the stellar magnetic 
fields play an important role. 
These are very violent and dramatic 
events. 
You can see that here in this movie. 
That bubble is, approximately 100 billion 
kilometers across, and it's dramatically 
growing. 
these other stellar types are the higher 
mass analogues of T Tauri stars. 
All star formation is accompanied by this 
violent outflow. 
This is what cleaned out the solar 
system. 
And now, having shaken that off, the sun 
is indeed ready to settle in with the.