[meteorite-list] NASA Supported Research Helps Redefine Solar System's Edge (2012 VP113)

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Wed, 26 Mar 2014 11:14:17 -0700 (PDT)
Message-ID: <201403261814.s2QIEH59007104_at_zagami.jpl.nasa.gov>

http://www.nasa.gov/content/nasa-supported-research-helps-redefine-solar-systems-edge/index.html

NASA Supported Research Helps Redefine Solar System's Edge
NASA
March 26, 2014

[Images]
These images show the discovery of 2012 VP113 taken about 2 hours apart
on Nov. 5, 2012. The motion of 2012 VP113 stands out compared to the steady
state background of stars and galaxies.
Image Credit:
Scott Sheppard/Carnegie Institution for Science

The solar system has a new most-distant family member.

Scientists using ground based observatories have discovered an object
that is believed to have the most distant orbit found beyond the known
edge of our solar system. Named 2012 VP113, the observations of the object
-- possibly a dwarf planet -- were obtained and analyzed with a grant
from NASA. A dwarf planet is an object in orbit around the sun that is
large enough to have its own gravity pull itself into a spherical, or
nearly round, shape.

The detailed findings are published in the March 27 edition of Nature.

"This discovery adds the most distant address thus far to our solar system's
dynamic neighborhood map," said Kelly Fast, discipline scientist for NASA's
Planetary Astronomy Program, Science Mission Directorate (SMD) at NASA
Headquarters, Washington. "While the very existence of the inner Oort
Cloud is only a working hypothesis, this finding could help answer how
it may have formed."

The observations and analysis were led and coordinated by Chadwick Trujillo
of the Gemini Observatory in Hawaii and Scott Sheppard of the Carnegie
Institution in Washington. They used the National Optical Astronomy Observatory's
13-foot (4-meter) telescope in Chile to discover 2012 VP113. The telescope
is operated by the Foundation of Universities for Research in Astronomy,
under contract with the National Science Foundation. The Magellan 21-foot
(6.5-meter) telescope at Carnegie's Las Campanas Observatory in Chile
was used to determine the orbit of 2012 VP113 and obtain detailed information
about its surface properties.

"The discovery of 2012 VP113 shows us that the outer reaches of our solar
system are not an empty wasteland as once was thought," said Trujillo,
lead author and astronomer. "Instead, this is just the tip of the iceberg
telling us that there are many inner Oort Cloud bodies awaiting discovery.
 It also illustrates how little we know about the most distant parts of
our solar system and how much there is left to explore."

Our known solar system consists of the rocky planets like Earth, which
are close to the sun; the gas giant planets, which are further out; and
the frozen objects of the Kuiper belt, which lie just beyond Neptune's
orbit. Beyond this, there appears to be an edge to the solar system where
only one object somewhat smaller than Pluto, Sedna, was previously known
to inhabit for its entire orbit. But the newly found 2012 VP113 has an
orbit that stays even beyond Sedna, making it the furthest known in the
solar system.

Sedna was discovered beyond the Kuiper Belt edge in 2003, and it was not
known if Sedna was unique, as Pluto once was thought to be before the
Kuiper Belt was discovered in 1992. With the discovery of 2012 VP113,
Sedna is not unique, and 2012 VP113 is likely the second known member
of the hypothesized inner Oort cloud. The outer Oort cloud is the likely
origin of some comets.

"The search for these distant inner Oort cloud objects beyond Sedna and
2012 VP113 should continue, as they could tell us a lot about how our
solar system formed and evolved," says Sheppard.

Sheppard and Trujillo determine that about 900 objects with orbits like
Sedna and 2012 VP113 with sizes larger than 621 miles (1000 km) may exist.
 2012 VP113 is likely one of hundreds of thousands of distant objects
that inhabit the region in our solar system scientists refer to as the
inner Oort cloud. The total population of the inner Oort cloud is likely
bigger than that of the Kuiper Belt and main asteroid belt.

"Some of these inner Oort cloud objects could rival the size of Mars or
even Earth,? said Sheppard. This is because many of the inner Oort cloud
objects are so distant that even very large ones would be too faint to
detect with current technology."

2012 VP113's closest orbit point to the sun brings it to about 80 times
the distance of the Earth from the sun, a measurement referred to as an
astronomical unit or AU. The rocky planets and asteroids exist at distances
ranging between .39 and 4.2 AU. Gas giants are found between 5 and 30
AU, and the Kuiper belt (composed of hundreds of thousands of icy objects,
including Pluto) ranges from 30 to 50 AU. In our solar system there is
a distinct edge at 50 AU. Until 2012 VP113 was discovered, only Sedna,
with a closest approach to the Sun of 76 AU, was known to stay significantly
beyond this outer boundary for its entire orbit.

Both Sedna and 2012 VP113 were found near their closest approach to the
sun, but they both have orbits that go out to hundreds of AU, at which
point they would be too faint to discover. The similarity in the orbits
found for Sedna, 2012 VP113 and a few other objects near the edge of the
Kuiper Belt suggests the new object's orbit might be influenced by the
potential presence of a yet unseen planet perhaps up to 10 times the size
of Earth. Further studies of this deep space arena will continue.

For more details on the new dwarf planet, visit:

http://home.dtm.ciw.edu/users/sheppard/inner_oort_cloud/
Received on Wed 26 Mar 2014 02:14:17 PM PDT