Name: ULTIMATE PLANETARY CATASTROPHE | The Universe (Season 6) | History
Uploaded: 2020-03-19T19:11:17.000Z
Duration: 5 min 57 s
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over 4 billion years of planet-altering catastrophes.

like the craters of the late heavy bombardment

In others, the evidence has long since disappeared.

NASA has recently compared images of Jupiter

from the Cassini and New Horizons missions

Like Saturn, Jupiter also has rings, though much fainter.

And those ripples are formed when a portion of the ring

And then as it continues to spin and evolve over time,

If you unwind that system and work back out the ripples,

when that ring plane had gotten tilted over.

NARRATOR: July 1994 marks the date of the Shoemaker-Levy 9

The scientific sleuths had made a key discovery.

As the cometary fragments struck Jupiter itself,

much smaller debris passed through its rings,

tilting and twisting them into the ripples

In the case of a disrupted comet like Shoemaker-Levy 9,

across the disk of the rings raining through that system.

And so rather than displacing only one or two ring particles,

you can do the entire cloud at once, tipping it on the side.

the only comet to leave its calling card mark

In July 2009, another asteroid smashed into the gas giant

But when it impacted Jupiter, it brought up a lot of material

from deep within the atmosphere and created a huge scar

perhaps the size of the Pacific Ocean on the Earth.

NARRATOR: It's now estimated that an asteroid or comet hits

is 5,000 times higher than the rate of impacts on Earth.

And the fact that we've seen several of these

suggests that it's happening all the time because there

So there's a lot more impact activity on the outer gas

the Earth would be essentially a sitting duck

for all the debris, the comets and the asteroids

creating vastly larger numbers of catastrophes

on Earth than we've experienced through our history.

new threats will likely arise, and Earth itself

will face a cosmic day of reckoning that nothing,

In several billion years, many scientists

and Mercury, the smallest, will face off in an orbital duel.

And an innocent bystander, Earth, just might find

MICHAEL MISCHNA: Right now, our solar system

is kind of a paradigm of clockwork regularity.

But it turns out that the planets do affect

The planetary orbits are, over very long periods of time,

And if that happens, Mercury's orbit becomes

It becomes progressively more elongated until the point

If Mercury's orbit ever gets to the situation

where it's crossing Venus's orbit, then basically,

NARRATOR: Scientists have calculated one of four

might be ejected from the solar system, might smash into Venus,

or, in a worst case scenario, Mercury might collide

with the Earth, blasting away our mantle and atmosphere