Andy's Wiki
Solar System Scratchpad

[Boiler Plate]

Discovered after an extensive search for Planet X. Initially thought to be Earth size and dubbed the ninth planet, then continuously reduced in size as its brightness became clear and its large moon was discovered, until another object Eris was discovered in its region of space that was more massive than it, when it was demoted to a Dwarf Planet status. Considered by some a double dwarf planet due to its large moon. Also has three tiny moons and could support a ring system. First Kuiper Belt object discovered, in 2:3 orbital resonance with Neptune. Target of New Horizons spacecraft. Its surface may contain organics.

Plutonian System[]

  • Charon - Large moon of Pluto, contains a tenth of its mass, making it a double dwarf planet. Its surface is completely covered in water ice, possibly from geysers. This could imply that it has subsurface liquid water. Ammonia may be helping to keep this water liquid near the surface. Has only occulted a star twice, once in 1980, and again in 2005. Has 10% less rock than Pluto, suggesting it formed in a collision and coalesced with outer material, similar to Earth's moon. The impactors could have been each about half the size of the moon.
  • Nix - Ss:Nix
  • S/2011 P 1 - Ss:S/2011 P 1
  • Hydra - Ss:Hydra

Web Pages[]

New Horizons in the News[]

NASA Solicits Plans for Mission (Dec 2000)[]

Funding Approved (Apr 2003)[]

To Launch with Minimal Plutonium (Oct 2004)[]

Shipped to Goddard for Pre-launch Tests (Jun 2005)[]

Approaching Launch (Nov 2005)[]

Just About to Launch (Jan 2006)[]

New Horizons Approaches Jupiter (Jan 2007)[]

5 Year Into Voyage, Halfway There (Jan 2011)[]

Crosses Uranus' Orbit (Mar 2011)[]

Adjusts Course to Study New Moon (Aug 2011)[]

In Home Stretch (Jan 2012)[]

Proposal for Stamp (Feb 2012)[]

Moons and Rings Could Be Hazardous (Oct 2012)[]

En Route (Nov 2012)[]

Pluto Planetary Status[]

See also Eris

First classical Kuiper Belt object Discovered (1992)[]

Four "Plutinos" Discovered, One A Quarter Charon's Size (1993)[]

Texas Sized KBO 1996 TL66 Found (1997)[]

1996 TO66 Found (1997)[]

Campaign Saved Pluto's Status as a Planet (1998)[]

Pluto Safe From Demotion (1999)[]

Scientists Respond to Not a Planet Claim (Feb 2001)[]

Ixion Discovered, Possibly Larger than Charon (Jul 2001)[]

Quaoar Size Measured, Larger than Ceres (Oct 2002)[]

Orcus Discovered, Possibly Largest (Feb 2004)[]

Sedna 2/3s Pluto's Size Discovered (Mar 2004)[]

Other KBOs May Be Smaller than First Proposed (Nov 2004)[]

See also 2002 AW197

First KBO Found Larger than Pluto, 10th Planet? (Jul 2005)[]

Defining Planet (Aug 2005)[]

Thermal Emission Study "Confirms" Eris Larger than Pluto (Feb 2006)[]

Hubble Finds Eris to be Only Slightly Larger than Pluto (Apr 2006)[]

Definition to Include All Round Objects Around Sun as Planets Proposed (Aug 2006)[]

Downgraded to a Dwarf Planet (Aug 2006)[]

Pluto Planet Expo (May 2007)[]

Eris More Massive than Pluto (Jun 2007)[]

Plutoid Class Announced (Jun 2008)[]

Eris Could Be Smaller Than Pluto (Nov 2010)[]

See Eris, Pluto, Haumea, Makemake, Sedna, Quaoar

How I Killed Pluto and Why It Had It Coming Book (Jan 2011)[]

See also Eris, Haumea

5 Years After Demotion Still Controversial (Aug 2011)[]

Moonlet and Ring Studies in the News[]

Pluto and Charon May Have Formed By Impact Like Earth/Moon (Feb 2005)[]

Hubble Finds Two New Moons (Nov 2005)[]

Kuiper Belt Moons Common (Jan 2006)[]

Discoverers Describe Discovery of Pluto's New Moons (Feb 2006)[]

Pluto Could Have Rings (Feb 2006)[]

Pluto's Moons Get Ready for Their Closeup (Jun 2010)[]

Fifth Anniversary of Nix and Hydra's Discovery (Jun 2011)[]

Fourth Moon Found (Jul 2011)[]

Fifth Moon Found (Jul 2011)[]

New Horizons Adjusts Course to Study New Moon[]

What to Name New Moon (Jul 2011)[]

Simulations Show Pluto Could Have Ring System (Aug 2011)[]

Kerberos and Styx Named (Jul 2013)[]

Pluto Studies in the News[]

Solid Methane Confirmed and Other Surface and Atmosphere Composition (Aug 1993)[]

Pluto's Atmosphere Warmer than Previously Thought (Mar 2009)[]

Could Pluto Have a Subsurface Ocean? (Dec 2010)[]

Atmosphere Much Larger, Cometlike, and Contains Carbon Monoxide (Apr 2011)[]

Organics May be on Surface (Dec 2011)[]

Surface Changes in Hubble Maps (Feb 2012)[]

Sharpest Ground Based Images Obtained (Sep 2012)[]

Occultations in the News[]

Charon and Pluto Occult a Star (Jun 2011)[]

Pluto and Charon occults star Jun 23, then four days later, both Pluto and Hydra eclipse another star Jun 27
Sophia Captures First Eclipse, Will Try Second One
Other's Capture First Eclipse, Will Try Second One

Occultation to Be Viewed From Aircraft (Jul 2011)[]


Pluto Gets a Name (1930)[]

Student Documentary at International Film Festival (Apr 2007)[]

Pluto Features[]