The Universe: Total Eclipse

The Universe : TOTAL ECLIPSE
History Channel
Season. 5 Episode.7

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


EXCERPTS:
TOTAL ECLIPSE

"Total eclipse of the Sun
can be seen somewhere on Earth
an average of once every 16 months.


PENUMBRA
UMBRA


Only planets without eclipses
are Mercury and Venus
because they have no moons.


Eclipse on here on Earth are no other.
Cosmic Proportions
The Sun is about 400 times bigger than moon
But the sun also happens to be about 400 times farther away
from the Earth than the moon.
What that means is that
both the Sun and the Moon appear to be
almost exactly the same size in the sky.
Their sizes in the sky is crucial for eclipses.


EINSTEIN G. RELATIVITY
CURVE IN SPACE
"In 1915, Einstein published his predictions
that gravity causes space to curve,
and the light from stars would bend following that curve.

So if there were a star close to the Sun in the sky,
Its light would be bent by the Sun's gravity (curve).

The only way to test Einstein's prediction
was during an eclipse,
when the sun was darkened.
and the nearby stars were visible.

Eddington knew the accurate position of a star
that should have been blocked by the Sun
But if the Sun's gravity bent the star's light,
as Einstein said,
It would be seen in a different position altogether.


SOLAR CORONA
Without the occurance of total solar eclipses
It's really questionable today whether we actually even know
that the Sun had a corona -
an outer, hot, tenous atmosphere.


CHRONOGRAPHS
for Artificial Eclipses


KEPLER spacecraft
"In the beginning
In January 2010
the Kepler team announced
the discovery of the mission's
first five planets.
Four are gas giants like Jupiter, (Kepler 5b, Kepler 6b, Kepler 7b, Kepler 8b,)
the fifth the size of Neptune, (Kepler 4b)
Kepler saw their transit many times in first week,
it means they orbit their stars in a matter of days,
eclipsing their stars each time.

It means they are 10 times closer than the Mercury to our Sun.


Kepler is going to determine (in next 6 years)
if Earth-like planets
are common or rare,
and the answer either way
is going to be very interesting.
______________________

The Universe: Secrets of the Space Probes

The Universe : SECRETS OF THE SPACE PROBES
History Channel
Season. 5 Episode. 5

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


EXCERPTS:

On Dec. 14, 2009
a Delta II rocket delivered a small package into orbit
300 miles above the Earth
its called WISE.
And its creating the detailed infrared photograph
of the universe to date.

WISE's 4-million-pixel telescope
can only photograph infrared images
if the telescope is colder than the objects it searches for.


CASSINI

TITAN
Thick atmosphere
Hydrocarbons, methan, ethane...
Liquid Methane
Huygens Probe


"The history begins in the 1960s
with NASA's first attempts
to reach Earth's nearest neighbors.

"And our first six Rangers missed the Moon eniterely.
But we learned quickly."


1962, American probe, Mariner 2
is the first spacecraft to fly past Venus.

But in 1970, the first probe to land on the planet
isn't American, but Soviet.
The Venera


The Temp. is about 860 degrees F.
Boiling point is 212
and lead melts at a temp. slightly lower that 860.
so you'd have molten lead on the surface of Venus.


The technique is called Gravity Assist,
a virtual engine that harnesses the immense gravity
of planetary bodies
to assist a spacecraft on a planned trajectory.


THE ION ENGINE
for out of solar system.


Currently, the European Space Agency's Mars Express probe
holds the Earth-to-Mars speed title at six months

An Ion Engine could cut the travel time to Mars
down to just a mere few weeks.
Five weeks to Mars is only the beginning.


In 1995, in the Pegasus constellation,
just 50 light years from Earth,
scientists discovered the first true extrasolar planet,
51 Pegasi B


In the last decade or so
astronomers have been extremely lucky
to find 100s of planets around the other stars.

But the planets we've been finding are the large ones:
the Jupiters, the Saturns, some Neptunes.
We have not been able to find the Earth-like planets,
if they are out there.


Kepler mission
to find exoplanets
using 95-megapixel camera


Feb, 11, 2010,
A high tech solar probe arrives in space, locked and loaded.
its mission: watch the Sun, 24/7, in high definition color.
SDO


Scheduled for launch in 2015,
Solar Probe Plus will fly directly into the Sun's 2-million-degree corona
and survive.

Solar Probe Plus will get very close to the Sun,
within 8 or 9 solar radii from the Sun.
Now, for comparison, the Earth is 200 solar radii from the center of the Sun.

Solar corona: Though farther from the Sun's core,
it's actually hotter than the Sun's surface.

The Solar corona is very hot, millions of degrees of temp.
So you might think that if you were immersed in the corona,
you would get burned.
But there are so few particles
that the total amount of energy being transferred to a body
is less than the amount of energy being radiated.
SO, IN FACT, YOU WOULD FREEZE
if you were immersed in the solar corona.
as long as you had a good heat shield protecting you from the disk of the Sun.

_____________________________