The Solar System Missions

1
The Solar System Missions
2
Astronomers discover 'new planet'
Astronomers have detected what could be the
Solar System's 10th planet. It was first seen
by astronomers using California's Palomar
Observatory, and has been given the name "Sedna"
after the Inuit goddess of the ocean.
Observations show it measures about
1,180-2,360km (730-1,470 miles) across, making it
similar in size to Pluto. Astronomers now say
they have evidence that Sedna has its own moon,
although this needs to be confirmed, and is also
very red in colour. There is likely to be some
debate about whether it qualifies as a true
planet, but some scientists are already saying it
re-defines our Solar System. BBC News March
15, 2004
3
Whats New??
NEW YORK (AP) -- One of the nation's leading
science museums has quietly shaken up the
universe by suggesting that Pluto is not
necessarily a planet at all but just a lump of
ice. The startling suggestion comes from
scientists at the Rose Center for Earth and
Space, which opened last year at the American
Museum of Natural History in New York.
4
Comparative Planetology Dwarf Planets Pre June
2008
5
Comparative Planetology Plutoids and Dwarf
Planets Post 2008
Unclear if is in hydrostatic equilibrium
6
Comparative Planetology Plutoids and Dwarf
Planets Post 2008
Beyond a doubt, more to come (there are many
candidates)
7
Comparative Planetology Plutiods and Dwarf
Planets
8
Comparative Planetology Plutoids and Dwarf
Planets
Note 2003 UB313 is now called Eris
9
Ceres Goddess of Plants (Roman)
Discovered 01/01/1801 Classification Dwarf
Planet Remains classified as a Dwarf Planet, and
is believed to be the only object of its kind
10
Ceres
11
The International Astronomical Union has
reclassified Ceres, the first asteroid to be
discovered (and the largest and most massive
object in the asteroid belt between Mars and
Jupiter), as a "dwarf planet". Ceres was
discovered on January 1, 1801 (technically the
first day of the 19th Century) by Giuseppe Piazzi
at Palermo, Sicily. He named it after Ceres, the
Roman goddess of agriculture and grain.Ceres
was originally considered a planet, but when
dozens of asteroids came to be discovered, it was
reclassified in an asteroid. (I have an astronomy
guide from the 1830s that lists 11 planets, the
seven from Mercury to Uranus, plus Ceres, Pallas,
Juno, and Vesta, the first four asteroids to be
discovered.) I took this photo with a Canon
Digital Rebel in late July when Ceres was in the
constellation Piscis Austrinus Ceres is between
the marks at upper right.  Comments
12
(No Transcript)
13
Ceres
14
Pluto
Discovered 02/18/1930
Pluto was discovered in 1930. Pluto's satellite
Charon was discovered in 1978. Pluto is a
low-density planet made up of 97 nitrogen. The
combined mass of Pluto and Charon is 450 times
less than Earthís mass. It rotates once every
6.39 Earth days and it revolves around the sun
for 247.7 Earthís years. As of 2011 Pluto is
now known to have 4 objects in orbit around it.
The moons are Charon, Nix, Hydra and P4 (newest,
still to be named as of 07/21/11
15
Pluto Ruler of the Dead
Pluto is known as the ruler of the dead and lives
in the underworld and his name Pluto meant the
giver of wealth since many precious gems and
metals were found were he lived. His Greek name
is Hades, which means the unseen. He owns a giant
three-headed dog that guards the gates of the
underworld. There is a myth of how Hades got his
wife. When Hades got bored of the underworld, he
wanted a wife. So he went up to earth to kidnap
Persephone, the daughter of Demeter. When Demeter
found out that her daughter was kidnapped, she
became furious and went up to Jupiter. After a
while, Jupiter decided that six months,
Persephone would spend time with her mother, and
another six months she would become queen of the
dead. Whenever Persephone went down to the
underworld, Demeter would be said and her tears
would be the falling leaves of autumn. She would
be so sad that all the crops would stop growing
and everything would turn cold. When she saw
Persephone, she would happy again and everything
would come back to life, this is the mythological
theory of the seasons. Pluto has a helmet of
darkness that made him invisible during battle.
In astrology, Pluto rules your private life.
16
Pluto
Pluto Facts Sheet Classification Plutoid Mass
of planet (Earth1) 0.002 Mean density
(grams/centimeter³ ) 2.03 Interior Ice??
Surface Water Atmosphere mostly nitrogen
gas, just like that of the Earth and Saturn's
moon Titan, with the addition of carbon monoxide
(CO - what comes out of your car) and methane
(CH4). Moons 4
17
Pluto
This is the clearest view of Pluto and its
satellite Charon seen by the Hubble Space
Telescope and taken by the European Space
Agency's Faint Object Camera on February 21,
1994.
18
Pluto
Puto and its moons. HST in 2011.
19
Eris (Formerly 2003 UB313) Goddess of Strife and
Discord
First observed 2003 Classification
Plutoid Formal identification 01/05/2005
About 10 Billion kilometers from the sun (96.7
AU) Aphelion 97.56 AU Perihelion 37.77 AU
The name Eris was chosen because of the strife
and discord in the astronomical community over
the official designation of Eris and, maybe more
popularly, the designation of Pluto as a planet.
20
Eris
21
A view of the solar system from the north down.
The four circles show the orbits of Jupiter,
Saturn, Uranus, and Neptune. The yellow dot in
the center is the sun. The earth, if it were
shown, would be inside the yellow dot
representing the sun. The orbits of the two
outermost planets, along with their current
positions, are also shown. If you are worried
because the sun appears to not be the focus of
the orbital ellipse you are very observant! But
it is just a projection effect.
22
Sedna Spirit of the Sea
Sedna is the spirit of the sea according to the
peoples of northern Canada and Greenland, named
Inuit. Sedna resides at the bottom of the sea and
has power over all animals. Her control of the
sea, which the Inuit people depend on for their
survival, gives Sedna an enormous power. Inuit
people believe that success or failure in hunting
depend on her unpredictable mood.
23
Sedna
Discovered 11/14/2003 Classification
??? About 10 Billion kilometers from the
sun Aphelion 975.56 AU Perihelion 76.156 AU
It is not presently known if Sedna is in
Hydrostatic equilibrium (condition 3 of the IAU
planetary definition), so its classification is
currently not finalized.
24
Sedna
The discovery of Sedna resurrected the question
of which astronomical objects should be
considered planets and which should not. On March
15, 2004, articles in the popular press reported
that "the tenth planet has been discovered". This
question was answered under the new International
Astronomical Union definition of a planet,
adopted on August 24, 2006. It is unknown whether
or not Sedna is in hydrostatic equilibrium. If,
as currently suspected,16 it is, then it would
qualify as a dwarf planet. Sedna has a
SternLevison parameter estimated at between
8  10-5 and 6  10-3 times that of Pluto,17
and therefore cannot be considered to have
cleared the neighbourhood of its orbit, even
though no other objects have yet been discovered
in its vicinity.
25




Image above These three panels show the first
detection of the faint distant object dubbed
Sedna. Imaged on Nov 14 from 632 to 938 UT,
Sedna was identified by te slight shift in
position notes in these three pictures taken at
different times. Image courtesy NASA/Caltach.
26
Sedna
Astronomers have announced the discovery of a
large new planetoid named Sedna. Mike Brown of
the California Institute of Technology, Chad
Trujillo of the Gemini Observatory in Hawaii, and
David Rabinowitz of Yale University in
Connecticut discovered Sedna in November 2003.
The astronomers cannot be certain of the exact
size of the new planetoid, but they believe it is
the largest object discovered in our Solar System
since the discovery of Pluto in 1930. Sedna is
also the furthest object from the Sun that has
been found within our Solar System. Sedna is
probably a huge ball of ice somewhere between
1,280 and 1,760 km (800 and 1,100 miles) in
diameter. Sedna is remarkably reddish in color.
Astronomers think that exposure to radiation over
extremely long times may have altered the
chemistry of some of the compounds within the
ice, turning them red. Sedna orbits on the fringe
of the known Solar System. It is currently at a
distance of about 90 Astronomical Units (AU) from
the Sun, more than twice as far away as Pluto.
Its orbit is highly elliptical, and carries it
around the Sun once every 10,500 years. It will
reach perihelion (closest approach to the Sun) in
72 years at a distance of 76 AU, then slowly move
away towards its extreme aphelion distance of 900
AU. Numerous similar icy planetoids, known as a
group as Kuiper Belt Objects (KBO) or
Trans-Neptunian Objects (TNO), have been found in
the last decade. However, the TNOs seem to orbit
within about 50 AU from the Sun, thus Sedna
appears not to belong to that group. An area much
further from the Sun, called the Oort Cloud, is
thought to exist and be the source of many long
period comets. Sedna does not seem to orbit quite
far enough out to be part of the Oort Cloud,
however, and scientists are trying to figure out
how this new planetoid fits in to their big
picture views of our Solar System.
27
Comparative Planetology Plutoids and Dwarf
Planets
The study of objects in the solar system that are
not classified by the IAU as planets is still
evolving and will continue to evolve into the
future.