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Welcome aboard the System76 Transmission Log. The space station orbiting the Linux computer manufacturer, System76: home to handcrafted Open Source hardware and the makers of Pop!_OS.
You 3210.
Welcome aboard the System
76 transmission log.
Our broadcast is about to begin.
This is the latest on System 76
computers, many manufacturing and PopOS.
Now for your inorbit crew.
Thanks for joining us today.
I'm Emma, and I'm here with David from
production, and we're
excited for today's episode.
We have some great company announcements
and a really cool guest who'll be talking
about astronomy and his research
on Nebula space clusters.
We have our back to school sale going
strong until October 3, where you can
get up to $150 off computers and swag.
Giveaways will happen throughout.
Emma, are there any other community things
that happened last month
that you want to announce?
Well, as of this recording, we have our
first monthly pop meetup this
week, which is exciting.
We're going to be meeting at unique
locations every month to enjoy delicious
food and drinks and great conversation.
So I can't wait to make
all the new friends.
We are also hiring a mechanical
engineer and a production technician.
Both jobs are listed on our careers page.
That production technician position is
actually my position because
I will be leaving soon.
So if you want to come and take
my job, please come and do that.
It is a great company to work for.
That's awesome, but we'll miss you.
Wonder what's new in cosmic?
A lot.
We'll start with our
tiling and mouse updates.
We have some stacking updates.
The notifications are now existing in
their own Applet separate
from your calendar.
So multiple notifications from the same
applications will stack in the
notification center, reducing clutter.
Oklch.
Color encoder was implemented for custom
theming, and the pullkit system wide
permissions handling will now prompt a
password for special access or changes.
Also, there are some X Wayland fixes to
drop downs and pop ups
for X apps in Wayland.
The Ryzen Nine 7900 X 3d with AMD 3d
Vcache is now available on Thalio Major.
Recent gaming news has been about how it's
beating intel and performance for gaming.
So that's exciting.
All right, and that's the news.
Our interview this month is with Pascale
and his research work in globular
clusters, which we thought was fitting
with the excitement of the
Nebula product launch.
Why don't you start by telling
us a little bit about yourself?
Yeah, definitely.
So I'm Massimo Pascali.
I'm a fifth year graduate student
at UC Berkeley Astronomy.
I did my undergrad at the University of
Arizona in Tucson and graduated in 2019,
after which came over here to start
my graduate studies in astrophysics.
And so I've been doing that now for five
years and still loving every bit of it.
So you're studying
astrophysics at Berkeley.
What is something within astrophysics that
you're particularly
interested in right now?
My particular interest in astrophysics is
really how clusters of stars evolve and
how our observation of that can be aided
through gravitational lensing, which is
all stuff that I can get
into a little bit later.
But something that I find that's really
beautiful about astrophysics is that once
you gain a context for any individual
thing within it, you gain
an appreciation for it.
I think most things can
become very interesting.
So I guess that's a long winded way of
saying that this is what I'm
interested in right now.
But should I decide to move in another
direction, I'm sure that there are many
other things that I would be interested in
and will be interested in in the future.
In our last conversation with you, you
mentioned that you're studying early
galaxies and dark matter
in the Sunburst arc.
What is the Sunburst arc and
why that particular arc?
Right.
So before we get into what the Sunburst
arc is in particular, I think it's
important to explain what gravitational
lensing is and the context in which
we're viewing gravitational lensing.
And so Einstein, more than 100 years ago,
predicted that objects that have
mass or energy deform spacetime.
So we all kind of exist on this
spacetime, and our mass deforms it.
And when light travels, light actually
travels along those deformed paths, and
that's what we end up observing
as the gravitational effect.
So this is not just light, but it's really
every object, let's say a
comet, is flying by the Earth.
The gravitational pull of the Earth is
actually going to deflect
the path of that comet.
Right?
And what's very interesting and what
Einstein predicted is that light
does the exact same thing.
And so we're replacing the massive body,
which in this case, I had said was the
Earth, with instead a
massive galaxy cluster.
Take the mass of our sun, and you
multiply it by ten to the 15.
That's what you get as that
mass for the galaxy cluster.
So extremely, extremely massive.
And so that's situated far out from us in
space, situated behind that galaxy
cluster, is then even further
away, an individual galaxy.
And when something's very far away, we
usually refer to it in astronomy
as being high redshift.
And so that very distant, high redshift
galaxy, the light from it, you imagine
it'd be so far away that usually it would
be difficult to see because that light,
the intensity falls off as it's
further away and it becomes fainter.
But when it's situated behind that massive
galaxy cluster, as I mentioned, the
gravity from that massive galaxy cluster
ends up deforming spacetime and
changing the path of light.
And what's very interesting about that
distortion is that it
provides a magnifying effect.
So we actually see it brighter
than we would otherwise.
And so that's something that I find that's
very cool, is that these massive galaxy
clusters actually serve as natural
telescopes in the sky that allow us to see
galaxies that are much further behind
them, and we can see things a lot brighter
than we would be able to otherwise.
So that's gravitational lensing cool.
Yeah.
And so there's a lot of reasons why
this is an arc of great interest.
I think it used to be the
brightest known arc on the sky.
And so, because it was exceptionally
bright, that means that you can get very
high quality data astronomy,
particularly observational astronomy.
We're always fighting with the
noise in all of our data, right?
We're trying to find signal amongst noise,
and the brighter things have more signal,
and so we're able to pick out
more above all of that noise.
And so when we last talked, I was
interested in how the Sunburst arc could
be affected by small scale dark matter,
this matter that doesn't interact with
light whatsoever, but its gravitational
effects are still measurable, which is why
it still impacts this
gravitational lensing.
And so the distortion that we see in the
Sunburst arc and the magnifying effect
that we get is due to all of that
matter, whether it be visible or dark.
And so in the past, we were looking at
this arc, and we were trying to look at
how smaller scale changes in the dark
matter could affect what we
end up seeing in the arc.
But more recently, we've
actually shifted our focus.
So we spent so much time studying the
Sunburst arc from the perspective of,
okay, what was doing the lensing to now
looking at the Sunburst arc and thinking,
oh, the thing that's being lensed is
actually very interesting as well.
These massive, very young star clusters.
Almost hearkening back to what I said
before about my interest in astrophysics
can change, because once you get an
appreciation for a different type of
problem, I think most things in
astrophysics can be
found very interesting.
That's really cool.
Can you tell us more
about superstar clusters?
And when you say they are rare, what
does that mean in this context?
So let's back up to the scope of the
problem and talk about specifically why
I'm interested in the Sunburst
arc, which I alluded to before.
And so in the Sunburst arc, we have an
individual galaxy, and the galaxy has been
stretched out into this arc like shape.
When it gets all stretched out, we get to
see these finer details in the morphology
of the galaxy that we
didn't get to before.
And so when you actually look at images of
the Sunburst arc, I highly encourage you
to Google the Sunburst arc
and take a look at a picture.
It's very pretty.
You see all of these bright knots, these
sort of bright, little compact
circles within the Sunburst arc.
And so when you look at those with your
telescope, and in particular, when you
look at it with a spectrograph, so it kind
of splits up all of the light
into its different wavelengths.
You notice that has features that resemble
a very young, very massive star cluster.
We refer to these as superstar clusters.
And so why do we even care
about superstar clusters?
Well, first of all, getting the most
massive superstar clusters so we're
talking order ten to the six solar masses
is pretty difficult to do
in our local universe.
So, ideally, if we could, we would observe
everything in the local universe because
everything's very close by, and that makes
the data that we're able to get very, very
high quality, right, because it's closer,
and so everything's brighter and we get
higher signal to noise, but we
find that in the local universe.
So at low redshift or very close to us,
it's very difficult to find
these superstar clusters.
Whereas when we seem to go very far away
to the high redshift universe,
we seem to see more.
So when I say that we're looking at
something at high redshift, really what
I'm saying is that we're looking at an
object in the universe as it was
when the universe was younger.
We're really looking billions of years
into the past where the universe was a
different place, it was a bit
of a different environment.
And so because of that difference in
environment, it's maybe more conducive
towards discovering superstar clusters
of the high redshift universe.
So that's one reason why we might be
interested in looking up the Sunburst arc
is because it hosts the superstar cluster,
and the superstar clusters tend to be
difficult to find in the local universe.
But now let's go even one step further
back and say, okay, well, why should we be
interested in these superstar
clusters as a whole, right?
If I tell you that they're rare, that
doesn't really necessarily
mean that they're interesting.
There can be rare things that
are not worth exploring.
And so these tie into a different type of
star cluster that we refer
to as globular clusters.
And so globular clusters are some of the
most outstanding objects in astrophysics.
Before we move on to the next question, I
just wanted to say that I did Google the
Sunburst arc, and that is very fascinating
to look at, and I could not stop looking
at it for a good few
minutes while listening.
I highly encourage anybody listening to
definitely Google a
Sunburst Arc and take a.
Good look at it, right?
Yeah, it's very cool.
And because it's stretched
out, it's distorted.
It's not what you expect when
you look at space, right.
You don't expect to see some really long
looking thing, but, yeah, it's very cool.
I honestly probably wouldn't have given it
much of a second thought
without your explanation.
Thank you.
So I think you were about to tell
us more about globular clusters.
Right.
So when we look in the local universe, we
see these very compact clusters of stars,
and they're usually quite massive.
And for a long time, people thought that
these were what we call a simple stellar
population, meaning that they probably
all formed out of the same gas cloud.
And so that's how all
these stars form, right.
You have some gas cloud, eventually it
collapses, and as that gas collapses and
gets more and more dense,
eventually it starts to form stars.
And so in the simplest picture, you'd
imagine that there's some cloud sitting
out in space, at what point it collapses
and forms a whole bunch of stars that
are then all together in a cluster.
And so when we look at globular clusters,
we initially thought that
this was what was going on.
In particular, we're seeing it really
late in the stage of its evolution.
So all of these globular clusters
we see are billions of years old.
And so that's one reason why people are so
interested in them, is because
they're billions of years old.
That means that they formed when
the universe was very young.
And so people can sort of do an archeology
by looking at these globular clusters to
get an understanding of, okay, if we
understand how these form, then we might
have a general idea of how stars are
forming generally in the early universe,
right, because they're billions
and billions of years old.
And so these superstar clusters are sort
of thought to be the progenitors or
eventually evolved into
these globular clusters.
And so that's what's interesting about the
Sunburst arc, is that maybe we're looking
at something that will one day become
these old globular clusters that we see
in the local universe or nearby today.
And so this is all going to sort of
connect into what's called the
multiple populations problem.
So I had mentioned before that when we
looked at these globular clusters, we kind
of imagined them to be
simple stellar populations.
And by that I meant that the whole cluster
probably formed out of the same cloud.
And so the cloud, let's imagine the cloud
that it formed out of has some
characteristic, what we call metallicity,
which means how much metals does
it have relative to hydrogen?
And another way of saying that
is what's the chemical makeup?
Right?
So we know that the periodic table of
elements, typically most things, are
composed of mostly hydrogen, but there are
all of these other elements that we're
familiar with, things like carbon
and sodium and nitrogen, et cetera.
And so you imagine that the cloud is
probably some mixture of all of these
elements, and that it's probably
well mixed throughout, right?
So it's fairly homogeneous.
No matter where I look at the cloud, I
probably see the same distribution of
hydrogen and nitrogen
and carbon and so on.
And so when that cloud collapses to form
stars, I'd imagine that all of those stars
would have that exact same
chemical makeup, right?
And so we can actually do this.
We can go and we can look at the stars in
these globular clusters, and we can say,
okay, what's the chemical
makeup of these stars?
If we were operating under that assumption
that it was some simple stellar
population, that it just all formed out of
the same cloud, then we would expect to
look at every star and say, okay, it
has the exact same chemical makeup.
What's particularly interesting is that
when we look at these stars, we actually
end up seeing populations that fall into
broadly two categories depending
on their chemical makeup.
And so one has a chemical makeup that's
very expected if you look at
other stars in the field.
So ones that aren't in clusters, they seem
to have similar chemical makeups to what
you would expect in this population.
We call this the one p population.
Then there's a secondary population that
exhibits this weird correlation and
anticorrelation between certain elements,
that being something like nitrogen.
We see that nitrogen and sodium are
enhanced in these stars, while things like
carbon and neon seem to be more deficient
in these stars compared to what we would
expect or what we at least
see in this one p population.
And so we call this one that exhibits the
weird correlations and
anticorrelations the two p population.
And so I know that doesn't
seem like a big deal.
You're like, okay, so what?
There's some extra nitrogen in some of
these stars, but we can't come up with a
good explanation for really
what's going on, right?
And so that comes to the root of, really,
astrophysics, is that if we don't
understand what's going on and nobody can
seem to figure it out, then suddenly
it becomes a very big problem.
And so this has been known this
problem has been known for decades.
At this point, we've made some progress,
but we haven't quite gotten there.
You might ask, okay, well, what if we
could see these clusters as
if they were back in time?
Maybe we would catch the processes in
action that might be causing this weird
correlation we see between some of
the elements in the two p population.
And so that's where these superstar
clusters once again come into play.
I mentioned that a superstar cluster is
thought to be the thing that will
eventually evolve into a globular cluster.
And so if we look at these superstar
clusters when they're young, maybe we can
see the processes in action that could
lead to the multiple populations problem.
In particular, when we looked at the
Sunburst Arc, which is a superstar
cluster, we found that the nebula that
surrounds it, so the remaining gas that
surrounds it was significantly
enriched in nitrogen.
And this is similar to what
we see in those two p stars.
In those two p stars, we see that nitrogen
is enhanced relative to what we'd expect.
And so when we go and we look at the
younger version maybe, of this cluster, we
see that the gas that is surrounding it,
which may still be able to form stars,
right, that remaining gas may
form another generation of stars.
Seems to be nitrogen enriched, sort of
cluing us in, like, okay, well, maybe
we're seeing a progenitor of a globular
cluster here, and we're seeing the clouds
that will eventually become that two p.
Population what does the
nitrogen enriched mean or cause?
Right?
So I think now we're going to get
a little bit more into the weeds.
But I think it's a key thing to understand
the multiple populations problem.
First, what we have to do is we
have to understand how stars work.
And so stars work by doing what we
call fusing hydrogen into helium.
You might have heard a lot about in day to
day science about how on Earth we're
trying to get to trying
to be able to do fusion.
That's what stars do naturally, but
they're able to do it because
they have so much mass, right?
More than we could ever build up on Earth.
They're fusing hydrogen into helium, and
that's what causes stars
to sort of stay active.
That fusion of hydrogen into helium allows
the star to not collapse, and it's what
provides all of that light that we see
from the star and all of that energy.
And so there are a number of different
ways in which that can happen.
There's sort of the
very base way to do it.
But as you get to higher temperatures,
so the star is very hot.
As you get the star hotter and hotter, it
actually opens up new pathways for you to
fuse hydrogen into helium, in particular,
one that's called the carbon
nitrogen oxygen cycle.
So now we're getting very deep
in, but just bear with me here.
These carbon nitrogen and oxygen, they
actually serve as a catalyst for this
conversion of hydrogen into helium, but it
only becomes activated
at higher temperatures.
But because they serve as catalysts, as
soon as you can access it, as soon as you
are at those temperatures, it's going to
quickly become the most
preferred way to do it.
And when you do that, it causes certain
imbalances between the initial makeup that
you had of the star with respect
to carbon, nitrogen and oxygen.
And so what people think is that maybe
these very high temperature stars that are
undergoing this carbon nitrogen oxygen
cycle could be causing the
enrichment of nitrogen that we see.
But you still need a way to get
that material out of the star.
And so there are a lot of different ways.
We call this stellar winds, and I won't
get into the details, but the most massive
stars, which are also the highest
temperature stars, and hence the ones that
are undergoing this DNO cycle,
tend to spew out a lot of their
mass in the form of winds.
They're so bright, there's so much energy,
that it starts expelling out its own
material, and that material can eventually
get captured by gas clouds
that maybe surround the star.
And so when we're thinking about, okay,
well, what could be causing the enrichment
that we see of nitrogen in this nebula
that surrounds the Sunburst arc, right?
So there's this massive superstar cluster,
and there's this cloud that surrounds it.
And basically what we did is we looked at
the features of the cloud and we found
that the cloud had elevated nitrogen
compared to what we would expect.
And so maybe it's these very massive, very
high temperature stars that are undergoing
the carbon nitrogen oxygen cycle that are
spewing out material from them that might
be enriched in nitrogen and that's getting
captured by those surrounding clouds.
You could even take that a step further
and you could say, okay, well, now we have
some gas clouds that have
been enriched in nitrogen.
What if those clouds end up collapsing
and forming stars themselves, right?
Because that's how stars form.
And so maybe in the Sunburst arc we could
be seeing that two P population still in
its nebular form where the enrichment has
been caused by ejected material from the
most massive highest temperature stars.
What are some things you wish
people knew about space?
I think that when we think about the
general public and the relationship with
astronomy and space in general, people
definitely have an appreciation for how
big space is and how sometimes
unfathomably intricate
space can be, right?
So there's this great unknown out there
and all of these other stars and planets,
the giant clouds of gas and what have you.
And I think that is really great because
it gives everybody sort of
a sense of perspective.
I think when you learn about
the vastness of the universe sometimes it
can make you feel small and
that can be a good thing.
I think it can really change
how you see day to day life.
Indeed, Neil degrasse Tyson has a great
talk about how once we went to the moon it
gave people a greater sense of
understanding of the scale of the universe
and where we were within it and how that
changed people's relationship with the
Earth and really stuff like
climate change and such.
And so I think that's all really great,
but I think that's something
that people already understand.
Even if they don't, maybe they
can't put their finger on it.
I think it's something that
they already kind of know.
But from an astrophysicist perspective, I
think that something that's very cool is
that in the face of a universe that is so
vast, so complicated, so difficult to
understand, that really if we
take things one step at a time.
We take things one problem at a
time, one calculation at a time.
Slowly but surely, we can really build up
a very intricate picture
of what's going on.
The depth of knowledge we have about very
detailed things in space is really
sometimes very mind blowing and I think
goes to show just how much we've been able
to accomplish in the past, say 100, 200
years of really doing in depth
study of physics and astronomy.
I think that that's something that
I'd like people to keep in mind more.
I think people are very fascinated
by the mystery of space.
And that's great because space is
mysterious, and that's very cool, and it
gets people excited, but also to get an
appreciation for how much progress we've
been able to make and will continue to
make into understanding really this
beast of a universe that we have.
How do you see the future of astronomy
evolving with the integration of
computational techniques, advanced
telescopes, and collaborative
efforts among researchers?
I think that this is it's a difficult
question to answer, really.
We're at a stage where astronomy is
sometimes moving faster
than you can keep up with.
There are a lot of people that indeed are
able to make their careers off of just
really staying on top of the advancements
in things like computational techniques,
are becoming acquainted with the most
recent telescopes, but sort of
going down the list, I'd say.
So computational techniques, especially
the sort of now as we're entering in an
era where machine learning is becoming
more and more accessible, we're finding
more and more ways to apply that
to the problems of interest.
I expect that's going to continue to sort
of push the problems
that we have access to.
So there are a lot of problems that are
sort of locked behind closed doors
in terms of computation time.
They just take too long, especially
problems that have lots of data.
So this is also now combining
into advanced telescopes.
So we're now coming out with these
telescopes that can take incredible,
incredible amounts of data, sort of
pushing towards this more survey approach,
where you take lots and lots of data at
once of many, many different objects.
A great example of this would be the Vera
Rubin Observatory, which will
go up in the next few years.
We're starting to, at one point, have too
much data compared to the number
of people that can work on it.
And so whoever can sort of harness
computational techniques to be able to go
through very, very large amounts of data
in a reasonable amount of time and extract
the important information from it really
stands to benefit a lot from
the current era of astronomy.
And so I think this also goes hand in hand
with collaborative efforts, because each
of these telescopes really is a
massive collaborative effort, right?
So you might have fear of the recent the
James Webb Space Telescope that went up.
Of course, that was a huge collaboration
across people, really, around the world
and governments around the world.
And I think was like a crowning
achievement, really, for like it's like
an achievement for humanity as a whole.
We're in an era now where collaboration
between researchers is sort of more
accessible than ever, especially now that
people are more comfortable being online
and interacting through things like zoom.
I think that we're going to see even
more collaboration going forward.
And that's great because I think maybe
many people, when they think about
astronomers or physicists, they kind of
get the idea of somebody that's in their
office on the chalkboard
solving problems on their own.
But the reality is that we actually all
collaborate a lot, and that's really fun.
I think part of the most enjoyable
experience of astronomy and having success
in this field or attacking certain
problems is being able to do
it together with other people.
I think that more and more
collaboration is always a good thing.
I think it's on the rise because now
people are so connected, and at the end of
the day, I just really love collaborating.
I think it's super fun to be able
to do things with other people.
It sounds like it's a good
community to be a part of.
Yeah, definitely.
I think any community can have its ups and
downs, but I think we're all sort of
together trying to solve the same
problems, and there's a
mutual respect from that.
That's awesome.
So I know that you had selected
a Lemur Pro previously.
What did you take into account
when it came to your studies?
And why did you select a Lemur Pro?
When I was thinking about it, I kind of
wanted the most power that I could get in
the smallest footprint, so I guess the
highest density of power in a laptop.
And so the Lemur Pro seemed
to check all of those boxes.
I didn't really need to go up to the next
stage where I needed maybe
some dedicated graphics.
There definitely are astrophysicists that
make very good use of those, but
that wasn't me in particular.
So the Lemur Pro allowed me to have a lot
of power, a lot of ram
for what I needed to do.
And it was small enough that I felt very
comfortable taking it with me everywhere.
So in astronomy, I'm either going to and
from campus, and maybe that's difficult,
or maybe I'm going to a coffee shop.
And so I want to make sure
to have a small footprint.
But also one of the big benefits, and one
of the most important parts about our
field is that whenever we have a
discovery, you need to be
able to share that discovery.
And so usually we do that by
publishing papers, right?
And then we put the paper out on the
archive, or some journal
publishes that paper.
But there are so many papers coming out
every day, it's very difficult to keep
track of everything that's going on.
And even if you have a very cool paper, it
can end up getting lost in the sea of
other works that are
coming out day to day.
Often we'll go to conferences where
we will go and present our papers.
And so we hold an entire room of other
astronomers captive as we get to talk
about our work for 15 minutes, upwards of
an hour, depending on
what the conference is.
When I'm thinking about what device that I
want with me, I want one that I feel very
comfortable traveling with
to other states or to other.
Countries and being able to take
out in a conference setting.
I don't really want to lug out a giant
gaming computer when I'm sitting in a room
of 100 other astronomers and
somebody's trying to give a talk.
And so those were the main things that
factored into my Lemur Pro decision.
And I think that my intuition was right
because I really enjoy the size of it and
I never feel myself yearning for any more
power in the computer, particularly having
the I think there's 40GB of Ram
in the Lemur Pro that I have.
And that's very useful because it means I
can have a lot of different
projects open simultaneously.
I don't have to start closing out of
things and start from a clean slate.
I'm really loving the Lemur Pro and it
really checks all the boxes that I have.
Can you talk about the relationship
between open source and astronomy?
In astronomy, everything for the most
part is open source to some extent.
And the reason being is that the most
important or really the foundation
of science is reproducibility.
So if I come out and let's say I have some
big discovery and people say, okay,
well, how'd you get this big discovery?
I'll say, Maybe I wrote some giant
software that does some
big simulation, right?
But if they go, okay, well, show us the
simulation, and I say, no, you can't
see that this code belongs to me.
You can't see what's
going on under the hood.
Nobody's going to believe
what my results are, right?
If they can't go in and actually see all
of the little intricate details of what's
going on and more so be able to
reproduce my results, there's no point.
Open source, you could say, is really
foundational for the sciences.
And so within astronomy, we often stand on
the shoulder of giants in that there are
many people that devote sometimes even
entire careers towards developing these
very, very powerful softwares to
solve astrophysical problems.
A big part of the field is learning how to
use those softwares and apply it to the
problem in particular that you're very
interested in and sometimes synthesizing
many codes together or making your own
additions, et cetera, to be able to solve
the problems that you're interested in.
Having open source is very,
very important for that.
And being able to be comfortable working
with open source software or making your
own software open source
and publishing that is all.
I think a very key part of in particular
astrophysics is what
we're talking about here.
But I think really the sciences as.
A whole, what specific
software do you use for that?
I use a couple of different software.
So when we're thinking in the context of
just general problem solving, something
that you might want is something like a
Markov chain, Monte Carlo sampler or
something that allows you to sort of input
a likelihood function and then
minimize that likelihood function.
So you might come up with
some way to solve a problem.
You might say, okay,
well, this is my data.
So we've looked at our telescopes.
We have some set of data, and you might
say, okay, well, I want to know, I want to
understand what the cause of this data is.
And so to do that, you're
going to build a model.
You'll say, okay, I think that
the underlying astrophysics for what I'm
seeing works in this way, so
I'm going to build this model.
And then you might want to see, okay, now
that I have this model, my model is
defined by some number of parameters, and
maybe those parameters
are interesting to us.
So in the context of this gravitational
lensing, what I'm observing might be the
Sunburst arc, in particular, maybe the
positions or where I see the Sunburst arc
with respect to the rest of the galaxy
cluster, I might build some model for the
underlying mass, the underlying gravity
that's causing that gravitational effect.
And so that might be described by some
important parameters, a number one being,
okay, well, what's the total mass?
Right?
What is the full mass of the galaxy
cluster that's lensing the Sunburst arc?
If I want to be able to test that model
and solve for those parameters when
comparing it to the data, I might need
some code that would allow me to do that.
And so I might create some
sort of likelihood function.
You can think of if you remember from
maybe high school, the chi squared test.
That's a really great way of doing it.
This might be in the form of a large
Markov chain Monte Carlo software.
So popular ones being something like MC,
I think Stan is another popular one.
And in particular, like, a
nested sampler, like multi nest.
And so that's like a big open source code
that I could never hope to write myself.
Right?
Like, it would take way too long.
It would be way worse than these people
that really have dedicated large sections
of their careers to developing these.
But because it's open source, because it's
widely used and well tested by the
community, I can feel confident
applying those codes to my problems.
And then you can go a bit finer, which
would be codes that are specifically
within astrophysics, maybe I
really want to understand.
I'm looking at a star cluster, and that
star cluster is surrounded by a nebula,
and I'm seeing the light from that nebula.
To understand what's truly going on there,
you need to do a very intricate
calculation of how light from the stars
gets transferred through
the nebular clouds.
It's a very, very
complicated physics problem.
And there's some 50 year old now yeah, I
think 50 year old code that's been built
up over the course of somebody's career to
do this extremely well
and extremely powerfully.
And that's all completely open source with
extremely good documentation such that I
can use it and I can feel confident
that it's doing the right thing.
Rather than having to spend my whole
career developing a code to solve
a problem I'm interested in.
I now get to stand on the shoulder of
giants, as I mentioned before, and really
use somebody else's code, and
that advances my timeline.
Well, , we are coming up
on time to close out.
What advice would you give to aspiring
astronomers or those interested in
pursuing a career in the
field of astrophysics?
Right.
So I've got two pieces of advice.
Both are conflicting, but I think that
there's a happy medium that you can find.
So the first, I guess, is for those that
are thinking about astronomy, but maybe
they really haven't gotten into it yet,
I'd say start looking for opportunities.
It's never too early to start looking for
opportunities to get involved, and you'd
be surprised by the number of
opportunities that there are.
Hopefully, if anybody's listening to this
and they're thinking that they might be
interested, but they're not totally
sure, I'd say start looking for things.
Astrobytes is a great website to start out
with if you're looking for opportunities,
really at the undergraduate level.
The second piece of advice I have is
really for the very excited
aspiring astronomers.
So you're already trying to get into it.
You're sending emails to professors or
you're already trying to get involved in
certain programs or camps or what have
you, depending on what age level you are
and what level of or where you are in your
career, but also understanding that
astronomy, it's a marathon,
it's not a sprint.
Right.
This is the career, especially if you
choose to take the academic
route, it's a lifelong career.
You have a lot of time and there's going
to be lots of opportunities to sprint.
It doesn't need to be all the time.
And so definitely take things easy, enjoy
things outside of astronomy,
and keep in mind sort of the greater
perspective of where your career is going
and what the next steps are really
going far off into the future.
Cool.
Well, we appreciate you taking the time
to answer all our questions today.
Yeah, definitely.
This was really fun.
I always love talking about my research.
I think you'll find that any astronomer
loves talking about their research.
I think any space lover will
love talking about space.
Yeah, definitely no.
Thank you for the opportunity to do this.
3210 you.
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