The Universe: Asteroid Attack

The Universe : ASTEROID ATTACK
History Channel
Season. 5 Episode. 6

http://www.history.com/shows/the-universe
http://en.wikipedia.org/wiki/The_Universe_%28TV_series%29


EXCERPTS:

ASTEROID ATTACK

APOPHIS,
will pass close by 2029,
if it hits the KEYHOLE,
a region in space of one mile wide
then it will hit Earth in 2036.


Apohis was discovered in 2004.
1 in 250,000, possibility to impact on Earth.


Objects that are one km or 2/3 of a mile in diameter or larger,
we think there's about 940 of those, and we've discovered 86% of the population.
If you move to smaller objects,
say 100 meters and larger,
we think there's about 50,000
of those and we've discovered 10%.
And if you move to smaller still objects, 30 meter
and larger-sized objects we think there's about
2 million of those objects and we've discovered much less than 1%.


Now, down here, we've got a basketball-sized rock.
On average, about two of these slam into the Earth's atmosphere
EVERY SINGLE DAY.
Next is the small car-sized object.
This happens about ONCE EVERY TWO WEEKS.
But even something this big is probably gonna burn up completely
before reaching the Earth's surface.

For a typical object hitting the Earth's atmosphere,
it needs to be at least 100 feet in diameter.


But according to recently uncovered fossil records,
the-one-mile-wide Chesapeake bay asteroid
didn't seem to have the same globar effects as the
massive extinctions triggered by the
6-mile asteroid that killed the dinosaurs.


2001, NASA's "NEAR" landed asteroid Eros.
"The NEAR spacecraft even transmitted information back to Earth
for about two weeks while on the surface.
But it has lost its radio link with teh Earth.
and so now, it's simply sitting there, mute for million of years."

"The asteroid explorer Hayabusa, of the
Japan Aerospace Exploration Agency (JAXA)
recently one-upped NEAR.
It's the first spacecraft to ever land on an asteroid
and then return to earth.
It arrived in June 2010 after a four billion mile round trip.


DAWN
DAWN will arrive at 3200-mile-wide Vesta in 2011,
orbit for a year, then reach 600-mile-wide Ceres in 2015.


Asteroids are trackable, because they are close (Near Earth Objects).
Comets come from farther space, and they are not visible until they are 6 months away from Earth. so we have little time to react.


WISE (Wide field Infrared Survey Explorer)
2009 launched
WISE has already found 25,000 asteroids and more than a dozen comets
that were too dark to find using visible light.

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The Universe: 7 Wonders of the Solar System

The Universe : 7 WONDERS OF THE SOLAR SYSTEM
History Channel
Season. 5 Episode. 1

http://www.history.com/shows/the-universe
http://en.wikipedia.org/wiki/The_Universe_%28TV_series%29



EXCERPTS:

Number 7
ENCELADUS
Moon of Saturn
Cassini, Nov. 2009

"Enceladus has water.
Basically, liquid water coming out and freezing.
so it's called Cryovolcanism.


Number 6
RINGS OF SATURN
"Among the seven main rings,
Its estimated
That the gaseous planet
has thousands of rings comprised of 35
trillion-trillion tons of ice and dust.
containing roughly 26 million times
tha amount of water on Earth.

Scientists have found 62 moons
embedded in Saturn's rings.

DAPHNIS
a moon in Saturn's A ring
2.5 miles


NUMBER 5
Jupiter's GREAT RED SPOT
3 times the size of Earth


NUMBER 4
ASTEROID BELT
"If you're orbiting an asteroid
inside our solar system's Asteroid Belt.
You wouldn't able to see big cratered surfaces
of other asteroids flying right next to you.
In fact, they probably look
just like distant points of light.
That's because the average separations
between most asteroids
in the asteroid belt is much
larger than their actual sizes.
So they'd really just look like dots.

In fact, an average distance between to asteroids
can be one million miles.

CERES is the biggest asteroid in the solar system - a round ball.
The awesome 600 mile wide rock contains
the fourth of entire mass of the Asteroid belt.

Now Dwarf-Planet, like Pluto.

Near Earth Objects strike Earth almost everyday.


NUMBER 3
OLYMPUS MONS
350 miles wide.

"100 million years ago,
hot lava rivers poured down
from its peak to cover
million of square miles
of the red planet.

Today Olympus Mons
is 100 times the volume
of Earth's largest volcano,
Mauna Loa,
located on the big island of Hawaii.


NUMBER 2
SURFACE OF THE SUN

Photosphere

Solar activity runs through an 11-year cycle.
In 2013, our Sun will be
at the peak of this cycle
called the Solar Maximum.
At this time the surface of the Sun
could create the perfect storm.


NUMBER 1
EARTH

"Earliest volcanoes spewed out
massive amount of steam,
which condensed into rain,
and supplied the planet with water.

But recently new sources of water
have been suggested.
Comets.

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The Universe: Stopping Armageddon

The Universe : STOPPING ARMAGEDDON
History Channel
Season. 3 Episode. 8

http://www.history.com/shows/the-universe
http://en.wikipedia.org/wiki/The_Universe_%28TV_series%29




EXCERPTS:
STOPPING ARMAGEDDON
[stopping asteroids to hit the Earth]


"There are three fundamental steps
to stopping Armageddon.
Detection and Mitigation
comprise the first two.
The third and maybe most challenged one of all
is who makes the decision when to act.
...
Right now,
there are no protocols
about what to do,
when to act,
and who makes these decisions.
in the event
of an imminent Earth impact.

______________________

The Universe: Deadly Comets and Meteors

The Universe :DEADLY COMETS AND METEORS
History Channel
Season. 3 Episode. 6

http://www.history.com/shows/the-universe
http://en.wikipedia.org/wiki/The_Universe_%28TV_series%29




EXCERPTS:


Asteroids and Comets
hold secrets of universe
and building blocks of life
and
also enemy.


Asteroids
"Because they were formed at the same times as Earth
asteroids contain the same basic elements
we find on our planet to build things.


Fragments of asteroids
that actually survive an impact
with the Earth's surface
are called METEORITES.


Asteroid Belt - After Mars
Kuiper Belt - After Neptune - Ice and Dust bodies
Oort Cloud - couple of light years from Sun,


"In 1986, the Giotto spacecraft
became the first mission to fly by a comet.
It was Comet Halley.
the only one known to return within our human lifetime.
also visible to the naked eye.


"The so-called carbonaceous chondrite types of asteroids
which are typically found
in the outermost reaches of the main asteroid belt
have an almost exact match
between their deuterium-to-hydrogen ratios and Earth's oceans.


"Jupiter's gravity or light pressure from the Sun
can bump these cosmic relics out of the asteroid belt.
Similarly, the gravity from planet Neptune
can nudge comets out of the Kuiper Belt.


"65 million years ago, a cosmic object
roughly six miles across
impacted the Yucatan Peninsula
near the modern village of Chicxulub, Mexico.
It produced kinetic engergy equivalent to
eight billion Hiroshima atomic bombs.

Many scientists now believe the impact event
extinguished 75% of animal and plant species.

The next Chicxulub-sized impact
is estimated to occur 35 million years from now
but one can never by too certain when it comes to space rocks.


Somwhere on the order of 85 to 95 percent
of the objects that collide with the Earth
come from the main asteroid belt.


Although most potentially hazardous objects are asteroids
comets reamin a legitimate threat.
These icy bodies, which come from the outer solar syatem
can travel three times faster than asteroids.
so it takes only 9 months
for them to get from the orbit of Jupter
to the orbit of Earth.


Fortunately, Jupiter acts as a planetary shield.
It deflects or absorbs comets that drift towards Earth.
And scientists now have the pictures to prove it.
On July 22, 1994, telescopes around the world
caught a glimpse of one of the most violent comet impacts
in the history of humanity.

A String of about 20 comet fragments named Shoemaker-Levy 9
crashed into the upper cloud decks of Jupiter.


On June 30, 1908,
the biggest cosmic disaster in recorded human history
on Earth occurred in Russia.
A large object exploded in Siberia's remote Tunguska wilderness.


smallaer asteroids can create significant damage at the surface.

It's estimated to happen once every 500 years.

Believe it or not,
Earth takes a hit
from soccoer ball-sized space rocks every day.
Most go unseen.
But in 1992, amateur video caught a meteorite.
flash across the nighttime sky.


Congress mandated that NASA must detect
over 90% of near-Earth objects.
over a half-mile in diameter.


APOPHIS, size of city
This space rock will make a close pass
near Earth on April 13, 2029.

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