The Universe s02e12 Episode Script
Cosmic Collisions
ln the beginning, there was darkness and then, bang giving birth to an endless expanding existence of time, space, and matter.
Now, see further than we've ever imagined beyond the limits of our existence in a place we call "The Universe.
" Cosmic collisions they are among the most violent and life-altering phenomena in the universe.
From fender-benders to high-velocity impacts gravity is constantly moving everything around in space and so things are bound to collide.
Asteroids, comets, galaxies, and planets are some of the objects involved in these energized events.
Yet as violent and destructive as these collisions sound we may owe ourvery existence to them.
Darin Ragozzine is on the hunt for answers to an ancient collision that happened far off in space.
Ragozzine has zeroed in on a vibrant gray rock.
lt's the vestige of an ancient fiery impact involving two massive objects the largest being the size of Pluto.
This gargantuan rock, called 2003 EL61 is a member of a collisional family that orbitsjust beyond the planet Neptune.
Collisional families are groups of objects that have very similar shapes, sizes, and tilts as they go around the Sun.
They stayed in a tight cluster of orbits because they came from the same objects.
Objects that came from the same parent should be made out of the same material.
So, by studying the compositions and verifying that they're similar we can know that they came from the same origin.
Billions ofyears ago, 2003 EL61 and its family members were part of one gigantic body over a thousand miles across.
The mammoth object resided in the Kuiper Belt a repository for objects that didn't become planets in the outer solar system.
But at that time the Kuiper Belt was buzzing with loose objects.
The ice-covered rock eventually slammed into another object half its size at a speed estimated at 3,000 miles per hour.
The impact produced energy equivalent to ten billion atomic bombs.
lt also ejected large chunks of ice from the object each one ranging from 250 miles in diameter down to mere specks.
The fragmented pieces are now all members of a collisional family with 2003 EL61 being the largest piece.
We're here at a clay pigeon shooting range because the trajectory of the shards after a clay pigeon is hit is very similar to the orbits that family members take.
Once it's hit, the pieces fly out but they pretty much follow that same trajectory as they go down.
ln the case of 2003 EL61 the impact has been sending it rapidly spinning like an amusement ride, rotating once every four hours.
lt got hit sideways, and so it was spinning.
And because it's spinning so fast, it elongates itself pulls itself out, and it's shaped sort of like a football except it's more like a football where you let out some of the air and squash it on one end.
So 2003 EL61 is the fastest-spinning large object that we know anywhere in the solar system.
There's nothing else quite like this.
Planetary astronomer Mike Brown has conducted extensive surveying of 2003 EL61 the biggest and brightest known object in the Kuiper Belt.
lt's bright, it's big, but it's also very shiny because we think when the collision happened most of that ice got removed and the things around it.
And itjust left a little, thin layer of almost pure ice sitting on top of this rock.
And that's why it's so much shinier than everything else we see up there.
lt's that pure ice that's out there.
l think that 2003 EL61 is the largest object out there that had a collision that formed a family.
l really do think it's one of the largest collisions that occurred in the outer part ofthe solar system in the history of the solar system.
The impact not only created 2003 EL61 and its galactic family, it also produced two moons.
We're searching for them now and something like ten percent of Kuiper Belt objects have moons.
But all of these objects that we've looked at only a few have more than one moon.
lnfrared telescopes determine the size of these objects by measuring the heat they emit.
Although 2003 EL61 is a hundred times larger than its next biggest family member this fragmented group maintains similar orbits.
The pieces stay together and keep following each other in their orbits around the Sun.
So astronomers can identify collisional families by looking for common orbital characteristics.
So, the distance from the Sun, how elliptical the orbit is.
When you shoot a shotgun, the pellets go out into similar trajectories as the original object.
This is the same as in collisional families in the solar system which follow similar orbits after the collision as the original object was under.
And this is how we're able to identify them.
So after this collision happens, they are on slightly different orbits.
And like runners on a track, if they all stayed in their own lanes if they all ran about the same speed because the lanes have slightly different lengths after a while, ifyou looked at the track each runnerwould be at a different place along the track.
And this is the same forfamily members right now.
So even though they're not next to each other today when we look at them, we can still identify each in terms of the way their orbits are the way they go around the Sun.
Scientists wonder whether 2003 EL61 could eventually be involved in another collision.
lt seems as though Neptune is gravitationally tugging on it which will eventually change its orbit.
ln a hundred million years it's going tojust barely cross the orbit of Neptune.
At that point, it's hard to guess what's going to happen.
Neptune can either throw it into the inner solar system or it can try to toss it out or many different things can happen.
Objects are periodically bumped out of the Kuiper Belt and drift in the direction of the inner solar system.
These icy rocks become comets as they form long tails of ice and dust when moving towards our Sun.
Eventually, it will work its way perhaps to Jupiter.
At that point, Jupiter actually throws it out of the solar system.
No one has really thought about what would happen if something the size of 2003 EL61 hit Jupiter.
But smaller comets have been known to strike the gas giant.
ln July1994, the Hubble Space Telescope observed an astonishing event.
A string of comet fragments, called Shoemaker-Levy 9 crashed into Jupiter at the speed of130,000 miles per hour.
The largest cometary piece released six million megatons of explosive energy.
They impacted Jupiter about twenty times every seven hours until they were destroyed.
The points of impact left scars on the surface of Jupiter reminders of the violent event.
JPL senior scientist Don Yeomans has analyzed the Shoemaker-Levy 9 event.
The Shoemaker-Levy 9 impacts was an eye-openerfor the public and the scientific community in the sense that these cosmic collisions do happen from time to time and the energy that they could generate arejust enormous.
lt's a good thing this thing hit Jupiter and not the Earth 'cause there would've been a serious problem on Earth.
Had the Shoemaker-Levy 9 struck Earth it would have made devastating impact craters the largest about forty miles wide.
Any one of them could have destroyed a metropolitan city and churned up enough dust to block sunlight for months.
Jupiter, being in the outer solar system and being far more massive than any of the other planets combined takes a lot of hits that might have otherwise been destined for Earth.
So big brother Jupiter is out there watching us.
Jupiter acts like a planetary goalkeeper but will it be able to deflect 2003 EL61 if it breaks loose from the Kuiper Belt and tumbles toward Earth? lt's also possible that it could hit Jupiter like Shoemaker-Levy 9 did.
This object is about 2,000 times bigger than the thing that hit Jupiter, than Shoemaker-Levy 9.
So it would be an incredible explosion in the night sky.
lt would be the single most prominent thing that you could see.
lt would be bigger than the full Moon at least the tail of it.
Because collisional families are difficult to locate researchers are eager to study Less is known about collisional families in the Kuiper Belt simply because fewer Kuiper Belt members are known than we know about asteroids.
So less research has been done to try to find collisional families within the Kuiper Belt.
As of today, we know of only this one collisional family in the Kuiper Belt.
They're very hard to find and to recognize.
And we got extremely lucky with 2003 EL61 and its family.
We're working right now trying to figure out otherways that we might be able to find these additional families, 'cause they must be there but wejust don't know how to find them yet.
Like these clay pigeon pieces family members from the 2003 EL61 family all remain in similar orbits today.
We're able to follow them today and to learn more about the history of the Kuiper Belt and of collisions.
One enduring mystery is when the 2003 EL61 collision actually occurred.
We think we can look at where the different objects are now and try to essentially run time backwards and figure out when they were in this one big collision.
Our best guess is that that answer is going to be essentially at the very beginning ofthe solar system.
were probably created during one of the most turbulent periods in the history of our solar system when collisions were as common as stars in the night sky.
From the beginning, collisions have been a fact of life in space.
They created much of our universe, and at the same time destroyed some of it along the way.
Collisions are the way that you build planets.
Without collisions, you don't have planets to begin with.
You start out with very small particles each one of them collides together bigger and bigger and bigger and bigger until you slowly build up these planets.
At the same time, collisions can destroy planets.
The planets in our solar system were created during a period called the heavy bombardment that happened over And the collisions didn't stop with the heavy bombardment.
Over 600 million years later our solar system experienced another spike in collisions during a period called the late heavy bombardment.
Stray rocks, too small to become planets played interplanetary billiards striking and bouncing off other bodies with tremendous force.
There were chunks of things flying everywhere and so there were many, many, many collisions.
A lot of the craters that you see on the Moon were from that very early period right when the solar system was still forming.
And our Moon revealsjust howvolatile the period was on Earth.
We can even calculate to some degree based on cratering on the Moon just how often we got hit by these rather large objects say, six miles across.
Towards the end of the late heavy bombardment we do get asteroids hundreds of miles in diameter
Now, see further than we've ever imagined beyond the limits of our existence in a place we call "The Universe.
" Cosmic collisions they are among the most violent and life-altering phenomena in the universe.
From fender-benders to high-velocity impacts gravity is constantly moving everything around in space and so things are bound to collide.
Asteroids, comets, galaxies, and planets are some of the objects involved in these energized events.
Yet as violent and destructive as these collisions sound we may owe ourvery existence to them.
Darin Ragozzine is on the hunt for answers to an ancient collision that happened far off in space.
Ragozzine has zeroed in on a vibrant gray rock.
lt's the vestige of an ancient fiery impact involving two massive objects the largest being the size of Pluto.
This gargantuan rock, called 2003 EL61 is a member of a collisional family that orbitsjust beyond the planet Neptune.
Collisional families are groups of objects that have very similar shapes, sizes, and tilts as they go around the Sun.
They stayed in a tight cluster of orbits because they came from the same objects.
Objects that came from the same parent should be made out of the same material.
So, by studying the compositions and verifying that they're similar we can know that they came from the same origin.
Billions ofyears ago, 2003 EL61 and its family members were part of one gigantic body over a thousand miles across.
The mammoth object resided in the Kuiper Belt a repository for objects that didn't become planets in the outer solar system.
But at that time the Kuiper Belt was buzzing with loose objects.
The ice-covered rock eventually slammed into another object half its size at a speed estimated at 3,000 miles per hour.
The impact produced energy equivalent to ten billion atomic bombs.
lt also ejected large chunks of ice from the object each one ranging from 250 miles in diameter down to mere specks.
The fragmented pieces are now all members of a collisional family with 2003 EL61 being the largest piece.
We're here at a clay pigeon shooting range because the trajectory of the shards after a clay pigeon is hit is very similar to the orbits that family members take.
Once it's hit, the pieces fly out but they pretty much follow that same trajectory as they go down.
ln the case of 2003 EL61 the impact has been sending it rapidly spinning like an amusement ride, rotating once every four hours.
lt got hit sideways, and so it was spinning.
And because it's spinning so fast, it elongates itself pulls itself out, and it's shaped sort of like a football except it's more like a football where you let out some of the air and squash it on one end.
So 2003 EL61 is the fastest-spinning large object that we know anywhere in the solar system.
There's nothing else quite like this.
Planetary astronomer Mike Brown has conducted extensive surveying of 2003 EL61 the biggest and brightest known object in the Kuiper Belt.
lt's bright, it's big, but it's also very shiny because we think when the collision happened most of that ice got removed and the things around it.
And itjust left a little, thin layer of almost pure ice sitting on top of this rock.
And that's why it's so much shinier than everything else we see up there.
lt's that pure ice that's out there.
l think that 2003 EL61 is the largest object out there that had a collision that formed a family.
l really do think it's one of the largest collisions that occurred in the outer part ofthe solar system in the history of the solar system.
The impact not only created 2003 EL61 and its galactic family, it also produced two moons.
We're searching for them now and something like ten percent of Kuiper Belt objects have moons.
But all of these objects that we've looked at only a few have more than one moon.
lnfrared telescopes determine the size of these objects by measuring the heat they emit.
Although 2003 EL61 is a hundred times larger than its next biggest family member this fragmented group maintains similar orbits.
The pieces stay together and keep following each other in their orbits around the Sun.
So astronomers can identify collisional families by looking for common orbital characteristics.
So, the distance from the Sun, how elliptical the orbit is.
When you shoot a shotgun, the pellets go out into similar trajectories as the original object.
This is the same as in collisional families in the solar system which follow similar orbits after the collision as the original object was under.
And this is how we're able to identify them.
So after this collision happens, they are on slightly different orbits.
And like runners on a track, if they all stayed in their own lanes if they all ran about the same speed because the lanes have slightly different lengths after a while, ifyou looked at the track each runnerwould be at a different place along the track.
And this is the same forfamily members right now.
So even though they're not next to each other today when we look at them, we can still identify each in terms of the way their orbits are the way they go around the Sun.
Scientists wonder whether 2003 EL61 could eventually be involved in another collision.
lt seems as though Neptune is gravitationally tugging on it which will eventually change its orbit.
ln a hundred million years it's going tojust barely cross the orbit of Neptune.
At that point, it's hard to guess what's going to happen.
Neptune can either throw it into the inner solar system or it can try to toss it out or many different things can happen.
Objects are periodically bumped out of the Kuiper Belt and drift in the direction of the inner solar system.
These icy rocks become comets as they form long tails of ice and dust when moving towards our Sun.
Eventually, it will work its way perhaps to Jupiter.
At that point, Jupiter actually throws it out of the solar system.
No one has really thought about what would happen if something the size of 2003 EL61 hit Jupiter.
But smaller comets have been known to strike the gas giant.
ln July1994, the Hubble Space Telescope observed an astonishing event.
A string of comet fragments, called Shoemaker-Levy 9 crashed into Jupiter at the speed of130,000 miles per hour.
The largest cometary piece released six million megatons of explosive energy.
They impacted Jupiter about twenty times every seven hours until they were destroyed.
The points of impact left scars on the surface of Jupiter reminders of the violent event.
JPL senior scientist Don Yeomans has analyzed the Shoemaker-Levy 9 event.
The Shoemaker-Levy 9 impacts was an eye-openerfor the public and the scientific community in the sense that these cosmic collisions do happen from time to time and the energy that they could generate arejust enormous.
lt's a good thing this thing hit Jupiter and not the Earth 'cause there would've been a serious problem on Earth.
Had the Shoemaker-Levy 9 struck Earth it would have made devastating impact craters the largest about forty miles wide.
Any one of them could have destroyed a metropolitan city and churned up enough dust to block sunlight for months.
Jupiter, being in the outer solar system and being far more massive than any of the other planets combined takes a lot of hits that might have otherwise been destined for Earth.
So big brother Jupiter is out there watching us.
Jupiter acts like a planetary goalkeeper but will it be able to deflect 2003 EL61 if it breaks loose from the Kuiper Belt and tumbles toward Earth? lt's also possible that it could hit Jupiter like Shoemaker-Levy 9 did.
This object is about 2,000 times bigger than the thing that hit Jupiter, than Shoemaker-Levy 9.
So it would be an incredible explosion in the night sky.
lt would be the single most prominent thing that you could see.
lt would be bigger than the full Moon at least the tail of it.
Because collisional families are difficult to locate researchers are eager to study Less is known about collisional families in the Kuiper Belt simply because fewer Kuiper Belt members are known than we know about asteroids.
So less research has been done to try to find collisional families within the Kuiper Belt.
As of today, we know of only this one collisional family in the Kuiper Belt.
They're very hard to find and to recognize.
And we got extremely lucky with 2003 EL61 and its family.
We're working right now trying to figure out otherways that we might be able to find these additional families, 'cause they must be there but wejust don't know how to find them yet.
Like these clay pigeon pieces family members from the 2003 EL61 family all remain in similar orbits today.
We're able to follow them today and to learn more about the history of the Kuiper Belt and of collisions.
One enduring mystery is when the 2003 EL61 collision actually occurred.
We think we can look at where the different objects are now and try to essentially run time backwards and figure out when they were in this one big collision.
Our best guess is that that answer is going to be essentially at the very beginning ofthe solar system.
were probably created during one of the most turbulent periods in the history of our solar system when collisions were as common as stars in the night sky.
From the beginning, collisions have been a fact of life in space.
They created much of our universe, and at the same time destroyed some of it along the way.
Collisions are the way that you build planets.
Without collisions, you don't have planets to begin with.
You start out with very small particles each one of them collides together bigger and bigger and bigger and bigger until you slowly build up these planets.
At the same time, collisions can destroy planets.
The planets in our solar system were created during a period called the heavy bombardment that happened over And the collisions didn't stop with the heavy bombardment.
Over 600 million years later our solar system experienced another spike in collisions during a period called the late heavy bombardment.
Stray rocks, too small to become planets played interplanetary billiards striking and bouncing off other bodies with tremendous force.
There were chunks of things flying everywhere and so there were many, many, many collisions.
A lot of the craters that you see on the Moon were from that very early period right when the solar system was still forming.
And our Moon revealsjust howvolatile the period was on Earth.
We can even calculate to some degree based on cratering on the Moon just how often we got hit by these rather large objects say, six miles across.
Towards the end of the late heavy bombardment we do get asteroids hundreds of miles in diameter