StarTalk Radio - Cosmic Queries – Between Planets and Stars, with Jackie Faherty
Episode Date: November 22, 2019What lies hidden in the murky hallways of the cosmos? Neil deGrasse Tyson, astrophysicist Jackie Faherty, PhD, and co-host Chuck Nice answer your fan-submitted questions on brown dwarfs, interstellar ...objects, Planet 9, and more!NOTE: StarTalk+ Patrons and All-Access subscribers can watch or listen to this entire episode commercial-free here: https://www.startalkradio.net/show/cosmic-queries-between-planets-and-stars-with-jackie-faherty/Thanks to this week’s Patrons for supporting us:Scott Peterson, Kody Krier, Anette Woolsey, Joe Aguirre, Daniel Hargrove, Jill BurkeyImage Credit: NASA, ESA, Hubble; Processing & License: Judy Schmidt. Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to new episodes ad-free and a whole week early.
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From the American Museum of Natural History in New York City,
and beaming out across all of space and time,
this is StarTalk, where science and pop culture collide.
This is StarTalk. I'm your host, Neil deGrasse Tyson, your personal astrophysicist.
And today we're going to have a Cosmic Queries edition of StarTalk with my
co-host Chuck Nice.
Yes.
Chuckie baby.
Hey Neil.
All right.
What's happening?
Someone slipped in between us here.
That's right.
I got my friend and colleague.
Yes.
Not only professional colleague, but museum colleague, Jackie Faraday.
That's right.
Hi.
Hi.
Jackie in the house.
Hi.
In two houses.
Double house here.
Double house.
Double houses.
Double house here.
Double house.
Jackie is one of the world's experts on the worlds that exist between planets and stars.
Wow.
There's not a sharp boundary there.
You might have thought so.
Or maybe you never thought about it.
She's thought about it.
Yes.
And she and her peeps.
She's got a whole community of people. In fact, after we hired her, she brought other people after she came.
So this place, the American Museum of Natural History, is one of the intellectual centers of this subject.
Because of this woman right here.
That's correct.
That's really cool.
I'm going to take ownership of that.
You sure?
Yeah.
We actually have a, our research group has stickers and t-shirts and logo.
We have a logo.
And we made it out of.
Is that the logo with the subway letters?
The subway symbols.
Yeah.
Oh.
Because our subway symbols in New York City are circles.
Yes.
With letters inside of them.
Yes, they are.
So what's your design there?
So we are BDNYC.
Oh.
Which stands for Brown Dwarfs in New York City
Research Group.
Plus a B train stops
at this institution.
It certainly does.
So does the C.
That's correct.
B and C.
There you go.
So we solicited questions
from our fan base
telling them
we're going to have
the world's expert
on this sort of
nether world
between planets and stars.
Yes.
And in came
hundreds of questions. Hundreds. Yes. Hundreds between planets and stars. Yes. And in came hundreds of questions.
Hundreds.
Yes.
Hundreds.
Hundreds of questions.
Yes.
You've got them.
And I've got them.
Neither of us have seen it.
No, you haven't.
Not that it's a test.
No, no.
I love shows like this when I have one of my astrophysics colleagues,
because then I'll have to say a thing.
Right.
She knows everything.
I'm going to go get lunch, and then you tell me when you're done.
Right.
I like that.
Neil saying, I know everything.
That's a nice compliment.
Thank you, Neil.
Yeah.
All right.
Well, listen, why don't we jump into it with our first question, which is always from a
Patreon patron.
All right.
Okay, here we go.
This is AMZ Industries.
Wow, we've gone corporate with Patreon patrons.
AMZ.
AMZ Industries.
That sounds very New York Stock Exchange listening.
Tell me about it.z right um amz says
um the sun is the biggest star in our solar system i believe it's also the only star in
our solar system keep going okay maybe i'm wrong i'm just saying that one yeah okay do we know a
star or any other object in space or interstellar space that is bigger than our sun?
Okay.
Okay, so they just mixed galaxy with solar system.
That's what they did.
Thank you.
I'm trying to figure this out, but you got it.
That's what they did.
Also to Jackie, do you believe in zodiac signs?
Okay.
All right.
Okay.
Twofold question.
Both of which are interesting to answer.
And they both sound completely unrelated to each other.
They are unrelated to each other.
I believe.
I think one is a genuine interest in the cosmos and the other is a genuine interest in you.
Oh, I love it.
So I will go
with the first one
is the sun
in our,
okay, so yes,
it's the only star
that we know of
in our solar system.
Although we have
searched for
another object
that might be
maybe not a star
but one of these objects
I study,
a brown dwarf.
Brown dwarf.
That might be a companion
to our own sun since it's alone, it's by itself, it doesn't have a partner. So dwarf. That might be a companion to our own sun.
Since it's alone, it's by itself.
It doesn't have a partner.
So are you...
We have to be orbiting really far away.
Yeah, I was going to say, because you're talking...
What I believe we're talking about, tell me if I'm wrong,
is that sometimes there are anomalies in the gravitational movement of objects in our neighborhood, right?
So I think you're going with the Planet Nine explanation.
Okay, that's what I...
Which is, yeah.
And that's also been pulled on and is very popular right now.
Planet Nine, not Pluto.
Just to be clear.
Right, yes.
On this show, we got to be clear about it.
That's right.
And also, we can discuss why that word planet's not very good in this context anyway.
Right.
So an object outside of what's currently Pluto's position that might might be tugging on in the outer part of the solar system the kuiper belt
which is this this this area of things that are left over from when the solar system formed uh
and whether or not there's something else that's well beyond that right possibly there's indications
theorists certainly think that. But there was this
nemesis hypothesis that existed
several years ago
for which that possibly you could
link up mass extinctions that happened
on this planet with a
highly eccentric other
object that might have been
The orbit is eccentric. Yes.
Orbit is eccentric. It's not emotionally eccentric.
It could have been emotionally eccentric.
Although it does spend a lot of time alone, so maybe you never know.
Why are we giving emotions to the objects?
Like, this is part of the problem.
People put so much emotion on these objects.
They want to feel them.
Yeah.
Yeah.
You just call the thing eccentric.
That's all.
Yes, eccentric.
Right.
So that it would have an eccentric orbit and that possibly it was every time it got into some area of the outer solar system,
it would kick a bunch of stuff in towards our area
and cause possibly mass extinctions.
Comets that would then hit right off.
Yeah, comets, asteroids.
And so that's basically we've looked far and near
and we haven't found anything.
Gotcha.
So possibly that's basically we've looked far and near and we haven't found anything. Gotcha. So possibly that's out.
So Nemesis was the proposed name if such an object existed
and that would have been its name had we found it.
Yeah.
And Nemesis is the idea that it's our Nemesis.
Right.
The Earth's Nemesis.
Not necessarily the sun's.
Right.
The Earth's because if it's going to basically go farther.
If it's launching crap at us.
Solvo.
Yeah.
Why would you want that?
Right.
That would feel like your nemesis, right?
Sure, sure.
So that, okay.
So beyond that,
the question's asking
if there's a star
that's bigger than our own sun.
And that's like, yeah, definitely.
There's so many.
My favorite star
in the nighttime sky
is called Ada Carina. Ada Carina. You know Ada Carina. Ada Carina's a beauty. sky is called Ada Carina.
Ada Carina.
You know Ada Carina.
Ada Carina is a beauty.
Love me some Ada Carina.
And I love the fact that it actually sounds like a pop star.
You know what I mean?
Ada?
Ada Carina.
Yeah.
It's in the constellation Carina.
They make a good ice cream flavor.
Ada Carina.
I Ada Carina?
No, no.
Carina is the name of the flavor.
And I Ada Carina.
Yeah.
Wow. I wouldn't have put that in there, flavor. And I ate a Carina. Wow.
I wouldn't have put that in there, but okay.
All right.
I like ice cream.
It's in the homunculus nebula.
Can you make that look as like the homunculus nuts that somehow somebody could make that you'd put on the ice cream?
Well, so ate a Carina is a very large star.
We now think that it's actually two stars, a binary star system.
We call it a luminous blue variable.
It's this object that's very, very massive.
And so we think it's two and so 40 to 50 times the mass of our own sun,
but probably two of them.
They go around each other, eclipsing each other,
so that you can actually see the light of one dip very, very periodically.
So that's a variability you were talking about.
Yeah.
Yeah.
So let me just ask you this.
That's a variability you were talking about.
Yeah.
Yeah.
So let me just ask you this.
Even though it's a body moving in front or transiting another body,
is one slightly larger than the other?
Because they're both luminous.
Yeah.
So the idea of a transit is one blocks light from the other,
but if they're both glowing, what are you measuring?
So they're not the exact same mass.
Okay.
So you'd have one that's, say, 60 times the mass of the sun,
and the other is 30 times the mass of the sun. I got you. All right.
There's even some hypothesis that there's a triple system in there.
There's three, not just two.
Wow.
So I'm noting Eta Carina because I think it is just an awesome star or star system.
But that's not the most massive.
But there's good Hubble photos of that, right?
Oh, yeah.
Yeah, yeah, yeah.
You check that out.
Yeah, we might put one on the website here.
You should.
That's cool.
Because it was part of an HST legacy project.
Hubble Space Telescope.
Sorry, Hubble Space Telescope, yes.
Don't apologize.
Yeah, you're right.
You're in the lingo, girl.
I'm in the lingo.
Do the lingo thing.
HST and the elemental peak.
Right, okay.
Thank you, Neil.
And it's a, so there's a lot of data on Adacrina.
But it's not the most massive.
You get even more massive.
There's 100, 200 times the mass of our own sun.
Wow.
And these are not stable systems.
Again, we're not referring to their motions.
Right, exactly. We have to their motions. Right. Right.
Exactly.
We have eccentric stars and unstable stars.
I like where this is going.
We actually have degenerate stars as well.
That's another thing.
Really?
Yes.
It's an actual kind of star.
Okay.
I can't even tell you.
Forget it.
My mind immediately went to a star.
Just for constellation weenies out there, Carina is a constellation visible primarily in the southern hemisphere,
and it's part of a much larger constellation that used to be one piece.
And it's the ship of the Argonauts.
Okay, Argonavis is the ship.
And it's just, Carina is the keel, I think?
The keel, yeah.
Yeah, so what they did was that constellation was way too big for the britches,
so they broke it up into parts.
There's a compass, there's a sail, there's the hull, there's the,
and so this is, it is the eta-if brightest object in the constellation Carina.
So alpha, beta, gamma, delta, epsilon, zeta, eta. So it would be the constellation Carina. So Alpha, Beta, Gamma, Delta, Epsilon, Zeta,
Eta. So it would be the seventh brightest star.
And that's important also because it's not
always the Eta because that's what
it was cataloged at. But at one time
it was one of the brightest stars in the
nighttime sky because the thing
is going through massive and insane
explosions. And it's just
dumping material off which is creating
That makes the beautiful photos.
Yes.
The nebula that's around it
is so unbelievably attractive to look at.
And that's just from...
But Chuck, it's really a crime scene.
...just dumps of material.
What's that?
Yeah.
It's really a crime scene.
Right.
You're gonna see this gas just spilling out.
So good.
Something happened down in there.
Yeah, something bad happened.
Something bad happened.
And something is continually bad happening.
I mean, I would love to fly close and have a look at that thing.
And you wouldn't want to be close as a human because there's probably a lot of really bad radiation around there.
But man, would it be a sight because it is really pretty.
That's very cool.
To the human eye.
So, Ada Carina.
Yeah.
Nice.
Also, the sun is large enough if you hollowed it out.
Right.
You could pour a million Earths into it. Our sun. Our Ada Carina. Yeah. Also, the sun is large enough if you hollowed it out, you could pour a million
Earths into it.
Our sun.
Our sun.
Right.
And now we're talking
about stars bigger than that.
That's right.
Much bigger.
Much, much, much bigger.
These supermassive stars,
these are the ones
that become black holes.
Like our sun couldn't
become a black hole,
could it?
No.
Our sun couldn't become
a black hole.
Not massive enough.
But these are the ones,
like you look at these stars,
the luminous blue variables,
and then there's another kind.
They're called Wolf-Rayet stars.
So there's actually somebody here.
Wolf-Rayet?
Yes.
Yes, actually debatable
if it's Wolf-Rayet
or Wolf-Rayet.
Well, these are two people
whose original research paper.
so did they discover this?
Well, they first studied them
in an important way.
All right.
And so then realized
that no other stars
look like those do, so they became their own
category. Nice. Wolfrayette.
R-A-Y-E-T. Okay.
In French, you don't pronounce the trailing consonant.
Right, so Wolfrayette. Nice.
Alright, and for the second question.
Reread that, please.
Which is, do you believe in
zodiac signs? So what I
believe is such an interesting thing.
There are constellations in the nighttime
sky, which are the markers
for where the ecliptic
of the path that the sun takes in the
sky and all the planets and the moon they take.
And so those are designations
in the sky and it's where
the sun and the planets and the
moon all move. Yeah. I don't
place any significance on
what people like to do
in reading their astrological sign.
I'm actually not even sure
what my sign is.
Oh, wow.
When were you born?
Not totally true.
I do know what it is,
but I'm just...
But you don't think about it
or care about it.
I don't think about it too much.
Yeah, it's not a thing.
Right.
Mine is cancer.
I'm a festering malignancy.
Thank you.
Does it feel accurate?
Oh, man. Allancy. Thank you. Does it feel accurate? Oh, man.
All right.
All right.
Enough of that.
Thank you, Jackie, for that.
That was great.
Wow.
I got so much out of that, man.
Chuck, what else you got there?
All right.
Why don't we...
This is Sherman from San Diego.
Are we still on the Patreon?
This is a Patreon.
Okay.
Sherman from San Diego.
Sherman says,
Hi, Dr. Tyson.
Hi, Dr. Faraday.
Understanding that it's only been a few decades
since the discovery of the first exoplanets,
there is still a lot we don't know
about even the closest ones to our solar system.
What tools and or resources are needed in the works or in the works to help us better
understand the nature and composition of these objects?
So that's a very good question.
Is there anything new and exciting that helps us?
Can I prepend that question by asking you, are your methods and tools to find the worlds
between planets and stars, do you have overlap with the methods
and tools of those who are finding planets?
Yeah.
And I actually think this would drive the question of what do we mean when we say the
word planet in this particular instance?
Because the objects that I study that I get the most excited about studying are ones that
we sometimes refer to as rogue worlds
as they are the same mass as the objects
that others might want to call a planet.
Those objects orbit a star.
And the ones that I study don't orbit a star.
They're in between.
Yeah, they just, they're off there.
They're alone.
They have no host star.
Homeless.
There's nothing.
They're homeless.
Yeah, we call them orphan to be nicer maybe. Wow.
Orphan, homeless, rogue. I'm an orphan world.
The orphaned objects
that are out there. So that what I do
because it's a lot easier
for you to attempt to get to what's in the
atmospheres of these objects when
they don't have a host star that you have to block
the light of because the contrast ratio
is so large. I haven't thought about that.
It's so much easier. Is that like seeing a firefly in a Hollywood searchlight?
You can't, the brightness contrast is so high,
you can't see the dim things.
So you got objects where there's no main star,
so it's just the object itself.
Very good.
Just it on its own.
But this is where it gets controversial, right?
Because it could be the exact same mass, temperature, gravity, the whole deal
that we would call an object around another star.
But because we find it alone, we call them brown dwarfs.
And when they're the lowest mass.
So not getting too far down this rabbit hole,
which I assume you want me to define what a brown dwarf is at some point.
Yeah, I was going to say.
It's probably important for your audience to understand
what I'm an expert in.
But just quickly, you're saying
that location matters
in how you classify
such an object. We don't have
a good running definition right now
for what it is
that we'll call this high mass
end problem outside of our own
solar system. High mass planet.
High mass planet.
High mass, so planet or...
So what's a brown dwarf?
So brown dwarfs are these objects that exist in mass
in between stars and planets or whatever,
the gray area in between.
And the idea being that when you form a star,
you have a giant molecular cloud of hydrogen
and it fragments into pieces.
Whatever causes the fragmentation, the compression of the gas, it breaks off into pieces.
The smallest possible pieces that could fragment off.
Wait, wait.
So you have the main piece, that's the main star?
Well, lots of pieces, right?
Okay, but one of them is going to, the big one is going to be the star.
There could be hundreds of them that'll be stars.
Oh, of course.
All right.
So now you've got the other bits and pieces.
Go on.
Yeah.
So there will be a whole spectrum, a whole distribution of objects that will break off out of a gigantic molecular cloud.
And this molecular cloud will break down into, once you compress it, so that all of the gas then gets pushed together.
And then enough so that the pressure there ignites the cores of these things
that break off into tiny pieces.
The smallest of the pieces end up being these objects
that don't even know that they don't have enough mass
to get the core hot enough to get nuclear burning going.
But they do it anyway?
No.
No.
No, this is why—
They think they're going to be a star, but they're not.
So now you guys are putting emotion on it.
They don't know what they should or shouldn't be.
They're just existing.
And so this is why people called them failed stars.
Right.
Because they're not getting enough mass.
But I look at it and like, whatever, dude.
Like, who cares?
It is existing with not enough mass.
That's fine.
It doesn't have the mass
instead
it can't get that
nuclear engine going
that's at the center
of our sun
instead
it's like a coal
plucked from a fire
it just cools
through its life
and that's it
and that is in between
basically what we say
is the top mass
for that that it happens
is 75 times the mass
of the Jupiter
75 Jupiters
that would be a star
that's the border right Above that is a star.
Right?
Exactly.
And this is very
metallicity dependent.
Like how much,
how much metallicity,
how much iron you have.
What's metallicity?
Oh, okay.
I got you.
Heavy elements.
So at the core,
like, okay.
Heavy elements.
So how much of that
was available will change
like how much mass
you need to get
the core burning.
But then,
the lower end of it,
the low end,
I don't know.
What's the lowest mass fragment
that you can break off?
This is a huge discussion
in astronomy right now.
What is the lowest mass piece
that breaks off?
And still becomes a thing.
And is a thing.
That right.
That thing that doesn't know
what it is.
But then,
wait, one last thing on it.
One last thing
because I know we have to stop.
But the planet
would be opposite end of this.
Can you form an object?
The planets form in a disk around a star.
But how big can it get around a star?
So now you've got two competing things.
You've got objects that form by breaking up a cloud that then self-fragments and blah, blah, blah, blah.
And then you've got a disc around a forming
star and how big can that
object get?
Planet versus brown dwarf.
So that's the brown dwarf
establishment right there.
As opposed to my brown dwarf which was
the dwarf that was never painted
by Disney because he was racist.
The eighth dwarf.
Chuck has issues
we're getting him through.
When we come back,
more with Jackie Faraday
on the world
between planets and stars
on StarTalk. Rain, space, and science.
Down to Earth.
You're listening to StarTalk.
We're back start off cosmic queries the worlds between stars and planets where are they what are they we got a word for them but do we understand them and our best chance of understanding them
is this woman right here yes jackie Jackie Faraday in the house.
Yes, yes. Friend and colleague
in the Department of Astrophysics right here
at the American Museum of Natural History.
And you just described something I hadn't
fully appreciated just before the break.
That you have this humungo
gas cloud, a
molecular cloud, they call them.
And it'll break into bits.
And these are typically stars, but some might not be stars.
In addition to that, each one of these will have a disk of material surrounding it
that will then break up into little bits beyond the bits that just broke off
to make the thing that had the disk.
Did I understand that?
You're doing good.
Yeah, yeah.
I will say, right.
So those are the— So two different kinds of phenomenon going on two different formation mechanisms formation mechanism
that's the phrase i'm looking for right and so we want to use that as definitional for saying like
what kind of object are you looking at i'd prefer to know how it formed because can you eject these objects that form around a star?
Yeah, you do. Oh, 100%
you do. They're launched off.
We probably ejected stuff all sorts
of ways. We might have like 30 planets or
something. Yes, exactly.
And now we're down to eight.
Get over it. And so
all this would be rogue planets by now.
Rogue worlds. Or eaten. Rogue worlds.
I like rogue worlds rather than planets.
Rogue worlds.
Or could have any of them become, join forces to become.
Get picked up by another star.
Yeah, get picked up by another star.
Yeah.
So we talk about that too.
That's pretty hard to do, but not impossible.
Okay.
It's possible that it could happen.
They could also, they get scattered around.
And we have evidence for this material now.
Like present day, we have material that has passed through our own solar system after it probably got ejected from a totally different solar system.
Nice.
This object called Oumuamua, which is an interstellar asteroid.
Right.
Rock that came flying through here.
And that probably got dumped out when its own sun was forming its solar system.
The one thing on this, though.
That ain't right.
That ain't right.
I know.
It's okay.
Don't let the doorknob hit you, Oumuamua.
But don't you think?
Oumuamua, by the way, is Hawaiian for scout.
And it's repeated, Oumuamua, for emphasis.
So it's basically first scout.
That's it.
And it was named that because it was found through a telescope in Hawaii,
the Pan-STARRS telescope, which is a wonderful telescope.
And as an homage to Hawaii, they chose this wonderful name.
Yeah.
So just I did this calculation long ago.
This is the perfect time for me to invoke it.
All right.
Because how often does one get to invoke a calculation?
Sweet.
If there were four bumblebees flying in the continental United States,
the chances of them accidentally bumping into each other
are greater than any two stars in our galaxy.
Oh, wow.
But if you want to talk about how empty space is between stars.
That's how much stuff is not there.
It's not there.
So if you have rogue things cast off,
there's still the unlikelihood
that you would even come into the vicinity
of another star.
But even if you did,
you're going to have a velocity
that's hard to trap.
So Oumuamua had hyperbolic velocity,
so it's coming through
and it's not even looking back.
No, it has nothing to do with us.
It's gangbusters.
Right, like we didn't capture it.
We're not doing anything with it. We're not doing anything with it.
We're not doing a damn thing.
It just, it came through like beep, beep.
Here I come.
There I go.
And even looking at its motion, its velocity,
it looked like maybe we were its first pass.
Possibly.
This is very hard to tease out,
but there was a paper on that,
whether or not we were the first.
A research paper.
A research paper that was looking at
whether or not we were its first encounter after it departed. A research paper that was looking at whether or not we were its first encounter
after it departed.
And we traced,
astronomers tried to trace it back
and see where it might have come from.
So now with that in mind,
did,
we're the first pass,
did we alter its course?
Oh, great question.
Yeah.
I don't know.
Maybe.
Probably a little bit.
Oh, yeah.
It feels,
yeah, you can, you can, you can not get captured,
but still feel what's going on here.
Okay.
Oh, yeah, yeah.
So if you look at, they have the trajectory.
Oh, yeah, yeah, yeah, yeah.
And the trajectory is arc.
Right.
Okay.
In response to the gravity of Jupiter and the sun.
Interesting.
But when you put enough of a change in the velocity
that when it gets to the next star,
it's really obvious.
Like, oh, this is its next stellar encounter.
I'm not sure we can tease it out quite yet
because it still looks like a disc.
It's like a disc object.
Just sort of flying around
in the disc of the Milky Way.
Nice.
Beep, beep.
What's that?
Roadrunner.
The Jetsons.
No, the Jetsons.
Oh, the flying cars.
Yeah, yeah, yeah.
Oh, I thought you were doing beep, beep from the roadrunner. It's before your time. Oh. No, the Jetsons. Oh, the flying cars. Yeah, yeah, yeah. Oh, I thought you were doing
beep-beep from the roadrunner.
It's before your time.
Sorry.
Ha!
Maybe.
She's like, okay.
Okay.
Yeah, Jetsons were so
before everybody's time.
I watched it when I was a kid,
so I don't know why it's before.
The roadrunner did a beep-beep too.
Yes, he did.
Yeah.
You know what I just learned recently?
This had nothing to do with anything.
The roadrunner
never left the road.
How about when he was standing on air and the coyote would fall?
No, the coyote's standing on air.
The roadrunner isn't.
That's true.
Oh.
Huh.
Interesting.
Yeah.
The roadrunner stops before it gets to the edge of the cliff.
And it's always on the road.
That's interesting.
Hence, the roadrunner.
Yeah.
I have another point on Stellar Fly.
Sorry.
I want to just pull us back in here neil um so you might like my pop culture references i'm sorry i love it i love it i love it i love it it's so great um but the one of the things that i think
is massively uh interesting right now in astronomy is how many times stars not run into each other, but interact with one another.
So the issue of, and this is my new thing, I'm really into the new villain of planetary
architecture is the stellar flyby.
The unappreciated influence that stars that move by each other can have.
And the reason why I say that-
Flyby looting.
Flybys that will change the structure
of maybe your planetary system.
Or now, like, okay, so the question, I think,
had something to do with what we're understanding
about exoplanets and learning about it in the future.
So here's one for everybody.
In 1 million years, just about 1 million, it's like 1.1 million years.
Okay, let me put that on my calendar.
Put it on the calendar.
October 12th.
October 12th, 1 million years.
Plus or minus like 10,000 years, yes.
But there will be a stellar flyby, so at its closest encounter,
by a star that's smaller than our own sun, but we're headed for each other.
And in one million years, it's going to pass within our Oort cloud.
It's coming straight in.
So the Oort cloud, the outer region of comets,
that's a spherical zone.
Very distant, but very there.
Very there.
Very there.
With lots of material.
Yeah, this is like trillions of comets just waiting to strike.
I was going to say, that sounds catastrophic.
We've looked at it.
Astronomers have looked at it to see, like, is it going to be a disaster?
And the conclusion is it's uncertain,
but the impact that it'll have on the Oort cloud might not be super bad.
Jan Oort was the Dutch astronomer who first calculated the existence of the Oort cloud.
It's so far away you can't see the objects at that distance.
But when they come in, you see them near the sun and you look at their trajectory.
And you say, oh, this must terminate way out at this distance before it comes back again.
The calls are coming from inside the house.
Okay.
But like, don't.
That's good.
So if you think about it,
the Oort cloud actually stretches
a third of the way to the closest star.
A third of the way.
Wow.
It gets loose.
So I mean, think about that, you know.
I mean, you get something that flies between us
and that next closest object.
It loosens up things.
Because they've only barely held on to begin with.
Barely held on.
So any disturbance will completely wreak havoc.
And most important here is the consideration of we're constantly doing mission planning.
Like, what are the next stages of mission planning, right?
And what's the name of the star, just so I know?
So it's Gliese 780.
Okay.
It's one of these names that I constantly mix it with 780 versus 781, I think.
So that's my fear of 780.
As do we all.
Gleeson 7...
Not Gleeson?
Gleeson.
G-L-E-I-S-E?
E-S.
Gleeson.
G-L-I-E-S-E.
E-S-E. E-S-E. It's a-L-I-E-S-E. E-S-E.
It's a catalog of high-moving, fast-moving stars, right?
Close, bright, so they're mostly fast-moving.
Yeah, yeah.
Fast-moving in our field of view.
So for that to be the case, they have to be nearby.
Man, I was hoping it was Gleeson.
No.
No, unfortunately.
But just to be clear, it's not.
So this is not a catalog of stars that are actually moving fast.
It's a catalog of stars that are moving fast in our field of view.
So you can have a bird fly by in front of you that's going maybe 20 miles an hour
and a plane that's moving past your field of view much more slowly.
Right.
And you're not going to say that the bird is going faster than a plane.
The bird is not going 600 miles an hour.
Right.
Right.
So that angle matters and that angle manifests by its distance.
So there's a catalog of selected for their fast movement in our night sky.
And those tend to be the nearest objects.
Yeah, right, because we're detecting them.
And so that one had been known,
we'd known about that star for a really long time.
It's a very bright star.
And it's...
It's headed for us.
We are headed for it.
It's heading for us.
And just think about it.
It's probably got a solar system around it
and a north cloud and a Kuiper belt.
Why not?
Why wouldn't it?
Probably the majority of stars,
why wouldn't they have them?
And so when you think,
I've got all of my,
every time I give a science talk,
I bring this up.
But don't you want to,
we're going to see it.
Totally want to get in it.
Come on,
bring it here.
Wait,
that means Oort clouds
will intersect.
More than that,
yes.
The Oort clouds,
the Kuiper belts,
possibly like whatever
this thing's got around it,
we could fly something to it.
There's a lot of this discussion
about going to Proxima Centauri
because we all want to get there
like now.
The nearest star to the sun.
Yeah, yeah.
Glees 780, man.
Let's go.
Let's do it.
That's going to be even closer
when it's close.
It's going to be so close.
She sounded like she's like
ready to be there for it.
I was going to say,
and I am so ready to do this
one million years from now.
You're talking like you got her telescope all ready for it.
This is very sad because I'll be dead.
You better take them longevity pills before that happens.
No, by then we'll be able to upload your consciousness to a computer.
That'll be so nice.
So you'll still be around.
That's good.
I'd like to see it when it happens.
Cool.
Chuck, what else you got?
All right.
So, okay.
This is, let's go for a quick one
because I know we're running out of time in this segment.
This is from Rossi King.
You can do a long one
and then I tease the next segment, dude.
This is how I do this.
Well, you know, if we keep discussing this like this,
we'll be able to do it with this short one.
All right.
Go.
No, this is Rossi King from YouTube.
Actually, I just wanted to ask this for myself too.
Was Jupiter a failed star?
And then the person says, I'm really glad it failed because I love it in the nighttime sky.
Oh, how cute is that?
That should be a quick answer.
Yeah, but is Jupiter a failed star?
Which, you know.
Yeah, yeah, no.
It's not.
No.
The quick answer to that would be no.
But again, let's not call them failed stars.
Let's just call them.
Achieving planets?
I call them over-excited planets.
Thank you.
Over-achieving planets?
I'm not kidding, Neil.
This is my coined term.
This is very modern teacher lingo, right?
Over-excited planets.
That's what I sometimes call them.
But then I don't like planets.
Don't star shame me.
Don't star shame me. You guys are good star shame me i'm not a failed star exactly jupiter shouldn't feel any in any way shape or form like it inadequate exactly right it is a behemoth of our solar system yes many times i say
if i'm gonna find an earth-like planet uh that I'll be comfortable saying, yes, let's consider that habitable.
I want a Jupiter at a Jupiter radius away
because you know what Jupiter does for us?
It protects us in a lot of ways.
It's the bouncer of the solar system.
It's the one that's like taking hits for us
because asteroids get dumped in
and comets are coming in.
And what does Jupiter do?
It takes a lot of hits.
Sure, it deflects some of them our way.
Let's not talk about that part.
Right.
But, unless you want to,
but I would say...
ID, please.
Most of what it does
is protect us.
It shields us.
It's a protector,
so I'd really like to see
if we find an object...
I like the bouncer
of the solar system.
ID, please.
He's standing out there.
ID, please.
Right.
That's what it says
to all the comments
as they come in.
Like, nope.
ID includes what your trajectory is. Yeah, there you go. Trajectory, please. Right. No, what it says to all the comments as they come in. Like, nope. ID includes what your trajectory is.
Yeah, there you go.
Trajectory, please.
Right.
No, that ain't happening. Keep walking.
So I would not call it a failed chart.
Call it the bouncer of the solar system.
The most important of the planets for Earth to consider right now.
So how much more mass would it need for it to have ignited a core of energy?
Or not even a core, for it to not have ignited a core of energy. Or not even a core, for it to not have ignited a core of energy.
And become the overachieving planet.
Right.
So the brown dwarf regime is roughly the lower mass bound that we call is about 13 times
the mass of Jupiter.
But that's not a great number.
That was a traditional number that was used.
So about a factor of 10.
Right. And the reason is because at that used. So about a factor of 10. Right.
And the reason is because at that mass,
you can get heavy hydrogen burning or deuterium burning.
And so because that tended to be a definitional thing
where either the difference between a star and a brown dwarf
is hydrogen burning, nuclear burning.
And then it was kind of capped at the bottom end of like,
well, at about 13 Jupiter masses,
then it's deuterium burning that stops.
And so, boom, that was the definition and it's terrible.
So the way to think about it is just,
if Jupiter had more than 10 times its current mass,
it would start entering the brown dwarf regime.
Yeah, it would be a massive thing.
But something about Jupiter, however,
that just Jupiter would be proud, I think,
is that it is emitting more energy
than it is receiving from the sun.
Yes.
So it is a net energy generating object in the solar system.
It's like a blue state.
Sorry, that was very political of me.
It was.
I'll fill in those details after this break
when StarTalk continues.
The world between planets. StarTalk.
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You're listening to StarTalk.
We're back on StarTalk.
Cosmic Queries.
The worlds between planets and stars.
And we have one of the world's experts.
Yes.
On that.
Jackie Farron.
One of my colleagues.
She's my colleague.
Right.
Yes.
Well, while I'm sitting here, I can be her colleague while I'm here.
Yes.
Exactly.
No, we get comedians here.
They're your colleagues.
Like, one of my people, she's my colleague.
Somehow I lose in this deal.
So we were talking about Jupiter as not a failed star,
but an overachieving planet.
But still it's a factor of 10 in mass
away from having turned on as a star.
So that's still kind of far away.
It's not kissing the door, you know,
kissing the boundary there, right?
Factor of 10.
No, yeah.
It's in squarely in the,
we're totally comfortable calling it a planet object.
It'd have to be quite a bit more massive
before we start to feel awkward.
There are other systems.
There's one called HR8799.
It's the name of the star.
And it has...
Again, named for the catalog out of which they come.
Yeah.
Right.
And these stars also have multiple names,
but that's the most popular of the names.
I often call that system.
That's the catchiest name.
HR 8799?
That's the most popular.
That's catchy.
That one just rolls off the tongue.
Rolls off the tongue.
That's like the share of the.
HR 8799.
So I sometimes call HR 8799 the Brad Pitt of planetary systems
that have been directly imaged.
Because if you have a camera,
aka a coronagraph or an adaptive optics system,
for astronomy.
Special camera for this, yeah.
Yeah, we point it at HR 8799 because it's so pretty.
Nice.
The system.
And you can image four.
One, two, three, four planets orbiting.
In one fell swoop.
Yeah, and I would highly recommend for your listeners.
Does Brad Pitt know this?
I have said it so much, I hope so.
Okay.
And that I'd like him to just feel like the honor of the Brad Pitt status of planetary systems.
HR 8799, he could just call himself the HR 8799 of...
Of Hollywood.
Of Hollywood.
I'm Hollywood's HR 8799, baby.
Switch it up.
Just so you know.
Point a camera at me.
So the year I was
the sexiest astrophysicist alive.
Okay.
This is 40 pounds ago, by the way.
I love that we are now
measuring chronology in pounds.
That's great.
Brad Pitt was the cover
as sexiest Man Alive.
Cute.
Beyond category.
She may have had to be in a category
in order to,
but he had no category.
What year is this?
Stop it!
I want to link it to HR in 79!
Next time, next question.
Don't want to answer it.
Oh, that was great.
Next question.
All right, so I have a question
personally that I just, I'm thinking now, and and I just I can't stop thinking about it.
As you were talking about these formation mechanisms, what I want to know is, is it possible to have those two formation mechanisms happen simultaneously?
happen simultaneously.
So, I'm sorry, the three formation mechanisms happen simultaneously so that you have that star that's being surrounded by a brown dwarf and planets.
Yes.
Can that happen?
So you're asking a question that basically got asked at a seminar the other day.
I ask it all the time.
And the result would be, is it possible that you can form a brown dwarf?
Yeah.
What this thing is that we call a brown dwarf.
These objects that have deuterium burning and they're formed through the process of fragmentation of a giant molecular cloud.
And you can make that same kind of object deuterium burning through the accretion process
or gravitational fragmentation around a star right and so can you get if you're going to count up all
the objects you would see at a certain mass you would start to get more of the object because
you're forming them two different ways and so you would see a higher number of objects
popping out as you get down to like,
maybe it's at 10 Jupiter masses,
maybe it's at 12, maybe it's at four,
whatever it is,
because you're doubling down on how you form them.
On the mechanism.
Yes.
You would double the number,
double, maybe triple, maybe quadruple,
or maybe just a little bit more.
But we're looking for this exact thing,
for counting up the numbers we get
and then seeing if there's any signature.
I take it back.
I take it back.
Pretty good.
Pretty good.
Yes, 100%.
All right, cool.
This is important.
Excellent.
So, Chuck, this is our final segment.
We got to go into, like, lightning round now.
All right, let's move into our lightning round.
Yeah, Elizabeth.
Okay.
Go, Chuck. This is such a a bell. Okay. Go, Chuck.
This is such a fascinating
So, Jackie, your answer
has to be a sound bite.
We're testing your sound bititude.
Got it.
Okay?
Ready.
All right.
Go, Chuck.
Okay.
This is Kristen Davies,
and Kristen says,
I'm a seventh grade
science teacher in Ohio,
and I ask my students
for their questions
on the topic today.
My students and I
enjoy listening to
clean episodes of Star Talk.
Okay? Now you see why I'm reading this? Episodes that don't have Chuck in them. And that's what I'm saying. Thanks a lot, Questions on the topic today. My students and I enjoy listening to clean episodes of StarTalk.
Okay.
Now you see why I'm reading this.
Episodes that don't have Chuck in them. And that's what I'm saying.
Thanks a lot, Kristen.
Yeah.
But I'm the one reading your question, Kristen.
Just remember that.
During our study times, I listen to other episodes of my commute to work, and that gets
me pumped up.
So here's what she says.
From the student, how many stars are in the universe?
Has anyone ever counted them?
And is it possible?
From the student, how many stars are in the universe?
Has anyone ever counted them and is it possible?
Another student says, can you turn a planet into a star?
One and two questions. Okay, first question, go.
All right, so number of stars in the universe.
Universe.
That number is insane.
Number of stars in the galaxy, we're going to go with 200 billion probably.
And so then there's billions and billions of galaxies.
That's why I'm saying too large for me to give the exact number second question can you turn a planet into a star
awesome question people are trying to figure this out unlikely because you dump enough material onto
it it probably gets fatter and you probably can't ignite unless you do a gigantic dump from
something that happens but we can do a quick, Jackie, we can do the calculation.
Yeah.
For the number of stars.
If you just say,
our galaxy has like 100 billion stars, let's say.
200, let's go with 200 billion.
But let's factor two between friends.
Yeah, yeah, sure, okay.
And to keep the math simple,
100 billion stars.
Okay.
And there's somewhere between
10 and 100 billion galaxies
in the observable universe.
So 100 billion times 100 billion, that's 10 to the 21st power.
Okay.
There you go.
What do you call that?
That's one sextillion.
Sextillion.
That's a sextillion?
Sextillion.
That seems very small.
Well, let's do it.
So a billion is, stay with me, nine zeros is a billion.
Right.
Trillion.
Okay. Count the zeros. It's just me. Nine zeros is a billion. Right. Trillion. Okay.
Count the zeros.
It's a 12.
10, right?
12.
Okay.
Units.
Three zeros at a time.
I know, because it would have been 100 billion.
Start again.
Okay.
So 12 trillion.
It's a trillion.
15 quadrillion.
Quadrillion.
18 quintillion.
Quintillion.
21 sextillion.
Right.
Yeah.
So that's all I'm saying
yeah
no but I'm saying
when I say that seems small
I mean it seems small
six trillion is small to you
yeah
no
I mean it's big
that's a number I don't say
because it's just
it's just too crazy big
no I'm talking about
I'm talking about when you
from where we're starting
I think
because you said
it's only a hundred billion
in our own galaxy in our galaxy oh okay alright forget it then from where we're starting, I think, because you said it's only 100 billion.
In our own galaxy.
In our galaxy.
Oh, okay.
All right, forget it then.
Plus, if there's not a sextillion stars,
then there's two sextillion.
Right.
At those numbers,
these factors are one, two.
They don't make a difference.
They make no difference.
You want to get the sense
of the scale of this
more than you want to.
But you still can't get
the sense of the scale.
And not all galaxies are our size.
No, there's small ones.
Small and big ones, yeah.
There's bigger ones.
There's collide galaxies that have merged and come together.
But another thing they asked about counting the number of stars.
And there is this survey called the—it's a European survey.
It's called Gaia and counting.
They have—they're called the Billion Star Survey.
1.7 billion stars.
And that's huge.
Those are not extrapolated.
They're actually counting.
Counted.
They've counted a billion stars.
Measure their distances, how far away they are.
It's the greatest map that humans have ever produced.
1.7 billion.
Billion.
Billion.
Objects in a catalog.
That's like a drop the mic moment.
Yeah.
I can't do that here. Okay. You did. Okay. He did it. I's like a drop the mic moment. Yeah. I can't do that here?
Okay.
You did.
Okay, he did it.
I was going to say,
please don't let that hit the ground.
Neil dropped the mic for Gaia.
Excellent.
Next.
Okay.
Keep it moving.
Go.
There we go.
All right.
This is from Twitter
and this is
Akshat says this.
I think that's the name.
Whatever.
Who cares?
How do astronomers study? Akshat cares. Akshat says this. I think that's the name. Whatever. Who cares? How do astronomers study...
Akshat cares.
Akshat probably cares.
How do astronomers study the atmospheres of brown dwarfs?
And how do we even detect them?
Yeah.
That's exactly what I do for a living.
Yeah.
And the way that we detect it is directly.
So that's the actual method that we call it.
Let's pause for a moment.
You can do that for a living.
Yeah.
I know.
That's a great thing to say.
Just reflect a moment.
Just a moment.
Oh, let's all hold hands.
Okay.
Meditative moment.
Okay.
There's a wonderful thing that you can do that for a living.
Yeah.
Okay, go.
Yeah.
I also say the tagline for astronomers, though,
is unlocking the secrets of the universe for a living.
Like, that's a good tagline, right?
You know?
I mean, sure, studying the atmospheres of Brown Dwarf sounds good, too,
but unlocking the secrets of the universe.
Okay, remember, we're in lightning round, so go.
I know, sorry.
Direct imaging is the technique that we use.
Okay.
And I basically take a telescope.
I point it directly at the object.
Oh.
For the most part, I have to use infrared instruments, though. So,
a wavelength of light that you can't see with your eye.
A wavelength that's a bit longer than the
radiation that we all give off,
the heat that we give off.
And I'll take it, and I'll take
the light, I pass it through a spectrograph,
and I look at what it's made, what is
the chemical composition? What kinds of
lines do I see? And mostly it's molecular features.
Molecules.
Very cool.
All right, cool.
All right, excellent.
There we go.
Keep it going.
This is Tom Cat.
Thank you, Tom.
Tom Cat wants to know this.
Do brown dwarfs have surfaces,
or are they just balls of hot gas?
Yeah.
Nice.
We're often asked this,
and there's no surface for you to stand on similar with Jupiter
and Saturn
you're not going there
and standing
and having a really nice time
no yeah
no we study
so they call them gas giants
yeah gas giants
and so brown dwarfs
are souped up gas giants
okay
very similar
so there's no point
deep enough
where it's dense enough
that you can call it a surface
there might be
we don't know
you just don't want to go
you don't want to test it
you'll die
we all die right
but that's hilarious
could they have some sort of core similar to Jupiter or Saturn which would have some sort of core I don't want to go. I don't want to test it. You'll die. We all die, right? That's hilarious.
Could they have some sort of core similar to Jupiter or Saturn, which would have some sort of core?
Very well, it could have that.
We don't know yet, though.
All right, good.
Excellent.
This is, ooh, Luigi Vanni.
Luigi Vanni says this.
How do we know what a planet is made of
and if it has an atmosphere, if it goes by how much light passes through or by it?
So that sounds like they're asking about the transit method.
Pretty much.
One of the ways that we detect planets is by looking at the planet pass in front of its host star between your eyeball and that host star.
And there's lots of methods that astronomers have developed to look at the light of the
star very, very carefully and see if there's any change in it as they are suspecting the
transit is happening.
You have to have the timing down, like smack down, to when that transit is happening.
You look right at the star and you can see what it's made of.
This is very complicated.
We see what the atmosphere of the planet, the transiting planet is made of.
Right. Through the light of the host star. It's a very complicated method. My preference,
just to re-gauge us back to brown dwarfs, is we draw upon what we do in brown dwarf science.
Since we directly detect the atmospheres, we can guide any measurements that you want to make when you're
trying to make detections
of objects. Oh, so you have ground truth of what
the atmosphere might be for those
who are looking for the transit in front of a
much brighter star in the background.
We are ground truth for transiting
planets, especially hot Jupiters,
these objects that are pretty close in that are like
Jupiter. Cool. All right.
Here we go. Actually, I think we just ran out of time.
Did we really?
We ran out of time.
Oh, man.
Yeah, Chuck, I'm sorry about that.
All right.
That's sad.
Oh, so many questions.
You know what I think?
We should have put a few of those online and have Jackie answer them.
Oh, that's a good idea.
We could do that.
Yeah.
I'll put in for that.
It's amazing.
People really are excited about brown dwarfs, man.
Into what you get paid for.
Yeah, I get paid to do this for a living.
Pretty good job.
Pretty good job.
All right, Jackie, thanks for being on Star Toys.
Not your first rodeo with us.
No, well, I've done all stars with Chuck,
but this is the first time we've ever done one.
It's our first time.
It is our first time.
Oh, so you go way back.
Yeah, I'm an HR AD. I'm an HRAD.
I'm an HRAD 799.
Of co-hosts.
All right.
This brings this episode of Stark Talk to a close.
I thank my co-host, Chuck Nice.
My friend and colleague, Jackie Faraday.
Thanks for coming on.
And as always, I bid you to keep looking up.