– a celestial body that, within the Solar System,

TNO’s

PLANET:

– a celestial body that, within the Solar System,

• is in orbit (path of one object around a point or another point) around the Sun;

• has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic

equilibrium (nearly round) shape; and

• has cleared the neighborhood (of its own orbital zone, meaning it has become gravitationally dominant, and there are no other bodies of comparable size other than its own satellites or those otherwise under its

gravitational influence) around its orbit;

– or

PLANET:

– or within another system,

• is in orbit around a star or stellar remnants;

• has a mass below the limiting mass for thermonuclear fusion of deuterium; and

• is above the minimum mass/size requirement for planetary status in the Solar System.

–

Dwarf planet:

• a celestial body that, within the Solar System,

• is in orbit around the Sun;

• has sufficient mass for its self-gravity to

overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape;

• has not cleared the neighborhood around its orbit; and

• is not a satellite

• The term "dwarf planet" applies only to objects in the Solar System. and is quite distinct from "planet"

and "small solar system body".

Pluto

– After the reclassification, Pluto was added to the list of minor planets and given the number 134340.

– A number of scientists hold that Pluto should

continue to be classified as a planet, and that other dwarf planets should be added to the roster of

planets along with Pluto

Trans-Neptunian Objects

DWARF PLANETS

• Plutinos are bodies

that orbit the Sun

at more or less the

same distance as

Pluto

Pluto’s Atmosphere

• When Pluto is within Neptune’s orbit, it has an atmosphere!

– As the planet moves further out in

to the solar system, the atmosphere

snows out onto the surface.

Pluto’s Atmosphere

• Little is known about Pluto's

atmosphere, but it probably consists primarily of nitrogen with some

carbon monoxide and methane.

• It is extremely tenuous, the surface

pressure being only a few microbars.

Pluto’s Atmosphere

• Pluto's atmosphere may exist as a gas only when Pluto is near its perihelion;

for the majority of Pluto's long year,

the atmospheric gases are frozen into

ice.

Pluto’s Atmosphere

• Near perihelion, it is likely that some

of the atmosphere escapes to space

perhaps even interacting with its

moons.

Pluto’s Moons

Pluto’s Moons

Charon

– The innermost moon,

– Was discovered by James Christy on June 22, 1978, nearly half a century after Pluto.

– Size: 749 miles

– Rotation, Rev, Distance, all the same as Pluto

Pluto’s Moons

Charon

– Rotation: 6 days/ 9 hrs/

18 min

(RETROGRADE) – Revolves: 248 years

– distance: 39.529 AU 3 674 490 973 miles

– Tilt 50°

– Incline: 17.2

– Almost like a double

planet system

Pluto’s Moons

Charon

• Pluto and its largest moon Charon would

fit comfortably within the United States.

Pluto’s Moons

Charon

• Charon orbits Pluto at a steep angle to

the ecliptic, and Pluto’s axis is heavily

tipped as well

Pluto

• Pluto is the only planet in the solar system that we

have not visited.

• However that is

soon to change.

Pluto

• 2015 New Horizon spacecraft will do a

Pluto Flyby

Pluto

• New Horizon

• ~45000mph (12mi/sec)

• NY to LA in 3½ min

• Pass Jupiter 13 months

• 13 years trip gets there about July2015

•

Pluto

• NASA probe, New Horizon, is

planning to arrive at Pluto while the atmosphere is still unfrozen.

• The probe will record the freezing of

the atmosphere.

Beyond Neptune

Most TNOs, like Pluto, come from an area

that is just beyond Neptune called the

Beyond Neptune

Trans-Neptunian Objects

Trans-Neptunian Objects

• More than 130 have been

discovered, one of them larger than Pluto!

• Other new

member of "dwarf planet" are

Eris and Ceres.

Trans-Neptunian Objects

• Here is a picture of

Ceres, Pluto, and Eris

Trans-Neptunian Objects

Not the typical asteroid… This

one is ROUND .

Trans-Neptunian Objects

Ceres

• Ceres was discovered on Jan 01, 1801 by Guiseppe Piazzi.

• Ceres has not yet been

seen up close but NASA's

Dawn spacecraft will visit

it in 2015

Trans-Neptunian Objects

Ceres

• The largest of the asteroids

• ITS ROUND

• The smallest of the dwarf planets.

• Orbit: 277 131 552 mile

from the Sun (average)

• Diameter: 590 miles

Trans-Neptunian Objects

ERIS (2003 UB313)

• Eris was first found by Mike Brown and his team in 2003.

• It was not until

2005 that Eris was identified as

another possible

planet in our solar

system.

Trans-Neptunian Objects

ERIS (2003 UB313)

• Is the largest known dwarf planet in

our solar system.

• It is a little larger

than Pluto. Eris is

about 1491 miles

(2400 Km) wide.

Trans-Neptunian Objects

ERIS (2003 UB313)

• Observations have led scientists to

believe it has

frozen methane on its surface.

• Eris appears gray

in color.

Trans-Neptunian Objects

ERIS (2003 UB313)

• Eris was the most distant member of our solar system.

• It is 3 times

farther out than

Pluto. One trip

around the Sun

takes 557 Earth

years for Eris.

Trans-Neptunian Objects

ERIS

• Dysnomia

is the only

moon of

Eris that

we now

know

about

Trans-Neptunian Objects

SEDNA

Very far far

away--farther than

Pluto is another Dwarf Planet.

8 billion miles away.

Sedna will be at its closest approach,

about 72 years from now and then it will beginning its

10,500-year trip back

to the far reaches of

the solar system.

Trans-Neptunian Objects

SEDNA

The last time Sedna (the red dot) was this close to the sun, Earth was just coming out of the last ice age.

The next time it comes

back, the world might

again be a completely

different place.

Trans-Neptunian Objects

SEDNA

Include its size and reddish color.

After Mars, it is the second reddest object in the solar system.

It is estimated Sedna

is approximately 3/4

the size of Pluto

Trans-Neptunian Objects

SEDNA

Coldest known

region of our solar system, where

temperatures never rise above -240°

Celsius (-400°F)

Trans-Neptunian Objects

OTHERS

Haumea with its moons, Hiʻiaka and Namaka

Haumea - A New Birth in Consciousness

(pronounced how-MAY-ah)

discovered on Dec 28, 2004

by Mike Brown

Trans-Neptunian Objects

OTHERS (136472)

Makemake (previously known as 2005 FY ₉

In Search of the Golden Egg

(pronounced MAH-keh MAH-keh

- "e" is pronounced

"ay" in Polynesian)

Discovered on March 31, 2005 by Mike

Brown

Trans-Neptunian Objects

OTHERS

• Quaoar (pronounced kwah-whar)

• name given to the "creation force“

• Discovered by Mike Brown and Chad Trujillo in a digital

image taken on June 4, 2002

Trans-Neptunian Objects

OTHERS

• Quaoar is about 746 miles in diameter--about

one-tenth the diameter of Earth, about half the size of Pluto, and larger than the four primary asteroids

combined.

Trans-Neptunian Objects

OTHERS

• Quaoar has an orbital period of 288 years

• Orbiting the sun

in a near perfect

circle

Trans-Neptunian Objects

OTHERS

• Orcus - Oath of the Soul

• Discovered on Feb 19, 2004 by Mike Brown

• Bit smaller than Pluto, Orcus has a nearly identical

orbital size, orbital period (year), and orbital inclination,

and it has a moon like

Pluto.

Trans-Neptunian Objects

OTHERS

• However, Orcus' orbital plane's orientation in our

solar system is tilted in the opposite direction from

Pluto's. Orcus is clearly Pluto's compliment.

Trans-Neptunian Objects

OTHERS

• Orcus's 247 year orbit is shaped similarly to Pluto's (both have perihelia above the ecliptic), but is

differently oriented.

• Orcus is sometimes described as the "anti-Pluto".

Oort Cloud

SO what is next?

Comets also are cosmic debris, probably planetesimals that originally resided in the vicinity of the orbits of

Uranus and Neptune rather than in the warmer regions of the asteroid belt.

Thus, the nuclei of comets are icy balls of frozen water, methane, and ammonia, mixed with small pieces of

rock and dust, rather than the largely volatile-free

stones and irons that typify asteroids.

Oort Cloud

SO…

In the most popular theory, icy planetesimals in the primitive solar nebula that wandered close to

Uranus or Neptune but not close enough to be

captured by them were flung to great distances from the Sun, some to be lost from the solar system while others populated what was to become a great cloud of cometary bodies, perhaps 10 trillion in number.

Such a cloud was first hypothesized by the Dutch

astronomer Jan Hendrik Oort.

Oort Cloud

Oort Cloud

• In 1950. Dr. Jan Oort noticed that:

– No comet has been observed with an orbit that indicates that it came from interstellar space

– There is a strong tendency for aphelia of long period comet orbits to lie at a distance of about 50,000 AU

– There is no preferential direction from

which comets come

THE END