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Cosma arrow.gif communication arrow.gif knowledge arrow.gif realm arrow.gif physical arrow.gif star arrow.gif solar system arrow.gif planet
planet : any of the large bodies that revolve around a star (planet, 2015) [1]blank.gifWebster | OneLook | Visuwords
dwarf planet : a celestial body that orbits the sun and has a spherical shape but is not large enough to disturb other objects from its orbit (dwarf planet, 2015) [2]blank.gifWebster | OneLook | Visuwords


What is a Planet?
The Dwarf Planets

Pluto, Eris, and Dwarf Planets of Outer Solar System
Dwarf Planets and Trans-Neptunian Objects (TNOs)

Solar System Exploration, Dwarf planets (NASA)

Take a tour of the solar system's dwarf planets (Mike Wall, Space.com)
Pluto's fall from grace classification led way for Eris, Haumea, Makemake and Ceres

Planets beyond Neptune

New Planet Found, Smaller Than Earth, Orbiting Distant Star (Ned Potter, ABC News)



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solar system
planets blank.gif Mercury | Venus | Earth | Mars | Jupiter | Saturn | Uranus | Neptune blank.gif
dwarf planets blank.gif Ceres | Pluto | Haumea | Makemake | Eris


How Many Planets? (They Might Be Giants)

Solar System Simulator

Solar System Exploration, planets (NASA)

NASA Planets

A Traveler's Guide to the Planets (National Geographic Channel)

Around the Solar System (Boston.com)

Table of Planets (Merriam-Webster)

The Nine Planets Solar System Tour

The Planets of the Solar System (Go-Astronomy)

These are links to resources organized by a classification scheme developed exclusively for Cosma. more...


Subject Specific Links

Solar System (ScienceZine)

OneLook Merriam-Webster Free Wiktionary Visuwords


Specific Dewey 523.4 Other Planets (BUBL LINK)
Free Internet Public Library dmoz Commercial Best of the Web

DuckDuckGo WolframAlpha

Library of Congress

WorldCat (OAIster) Library of Congress UPenn Online Books Open Library Hathi Trust

QB500 UPenn OnlineBooks

ISBNdb Google Books eBooks.com Barnes and Noble Amazon eBay Books

NASA Virtual Field Trip: "Solar System Math" Globio Glossopedia, Solar System

Open Education Consortium

The Planetary Society


Science News, Atom & Cosmos, Planetary Science NPR Archives Google News

Google Scholar



A planetary ring is a ring of cosmic dust and other small particles orbiting around a planet in a flat disc-shaped region. The most spectacular planetary rings known are those around Saturn, but the other three gas giants of the solar system (Jupiter, Uranus and Neptune) possess ring systems of their own. (Planetary ring, 2015) [3]blank.gif Wikipedia blank.gif
The Hunt for Ringed Planets

Planetary Rings Node

The rings of Jupiter | Saturn | Uranus | Neptune


Moons of the Planets (Go-Astronomy)

The moons of Earth | Mars | Jupiter | Saturn | Uranus | Neptune blank.gif dwarf planets blank.gif Eris | Pluto | Haumea

See also satellite


Closest is Proxima Centauri b

The exoplanet next door

Alien World 'Proxima b' Around Nearest Star Could Be Earth-Like

ESOcast 87: Planet found around closest Star (European Southern Observatory)

Proxima Centauri b - Press Conference at ESO HQ - HD

Closest potentially habitable planet to our solar system found (Ashley Strickland, CNN)
A Potentially Habitable World in Our Nearest Star (Abel Mendez, Planetary Habitability Laboratory)
Planet Found in Habitable Zone Around Nearest Star (European Southern Observatory)
Proxima b is our neighbor… better get used to it! (Pale Red Dot)
A terrestrial planet candidate in a temperate orbit around Proxima Centauri (Nature)


Three Earth-like planets found outside the Solar System

3 Strange Worlds Circling A Cool Star Might Be Prime Spots To Support Life (Nell Greenfieldboyce)
Scientists discover potentially habitable planets (Jennifer Chu, MIT News Office)
Temperate Earth-sized planets transiting a nearby ultracool dwarf star (Michaël Gillon, et. al., Nature)

Solar System Exploration, Beyond our Solar System (NASA)
NASA Planet Quest, 3D New Worlds Atlas

Extrasolar Planets News -- ScienceDaily
  • 'Iceball' planet discovered through microlensing Yesterday
    Scientists have discovered a new planet with the mass of Earth, orbiting its star at the same distance that we orbit our sun. The planet is likely far too cold to be habitable for life as we know it, however, because its star is so faint. But the discovery adds to scientists' understanding of the types of planetary systems that exist beyond our own.
  • Newly discovered exoplanet may be best candidate in search for signs of life Apr 19, 2017
    An exoplanet orbiting a red dwarf star 40 light-years from Earth may be the new holder of the title 'best place to look for signs of life beyond the solar system.' Using ESO's HARPS instrument, and other telescopes, astronomers discovered a 'super-Earth' orbiting in the habitable zone around the star LHS 1140. This world is larger and more massive than the Earth and has likely retained most of its atmosphere. This makes it one of the most exciting targets for atmospheric studies.
  • Collisions generate gas in debris disks Apr 12, 2017
    By examining the atomic carbon line from two young star systems -- 49 Ceti and Beta Pictoris -- researchers had found atomic carbon in the disk, the first time this observation has been made at sub-millimeter wavelength, hinting that the gas in debris disks is not primordial, but rather is generated from some process of collisions taking place in the debris disk.
  • Hubble spots auroras on Uranus Apr 10, 2017
    A composite image of Uranus by Voyager 2 and two different observations made by Hubble shows one for the ring and one for the auroras found around the planet.
  • Atmosphere detected around an Earth-like planet Apr 6, 2017
    Astronomers have detected an atmosphere on another Earth-like planet. This marks the first detection of an atmosphere around an Earth-like planet other than Earth itself, and thus is a significant step on the path towards the detection of life outside our Solar System.


NASA spots 54 potentially life-friendly planets (Seth Borenstein, AP Science Writer)

Top 10 Places To Find Alien Life (Lauren Effron, Discovery News)

Did We Meet Martians 36 Years Ago?.Analysis (Ray Villard, Discovery News)

Kepler News and Features
  • Planet Hunters Named in TIME’s Top 100 Most Influential People Apr 20, 2017
    Three extraordinary planet-hunters have been recognized by TIME Magazine as this year’s top 100 most influential people: Natalie Batalha from NASA’s Ames Research Center in California’s Silicon Valley; Michael Gillon from the University of Liège in Belgium; and Guillem Anglada-Escudé from the Queen Mary University in London.
  • Kepler Scientist on Time Magazine's Most Influential List Apr 20, 2017
    NASA's Kepler Mission Planet-Hunter Natalie Batalha Named to Time Magazine's 100 Most Influential List
  • Earth-Sized 'Tatooine' Planets Could Be Habitable Apr 12, 2017
    A new study explores potential climates of a planet orbiting two suns.
  • Light From An Ultra-Cool Neighbor Mar 10, 2017
    During the period of Dec. 15, 2016 and March 4, the Kepler spacecraft, operating as the K2 mission, observed TRAPPIST-1, an ultra-cool dwarf star home to seven Earth-size planets that are likley rocky. At image center is the light from TRAPPIST-1 collected by Kepler's onboard camera.
  • NASA's Kepler Provides Another Peek At Ultra-cool Neighbor Mar 8, 2017
    New observational data of the TRAPPIST-1 system from Kepler are expected to allow astronomers to refine the previous measurements of six planets, pin down the orbital period and mass of the seventh and farthest planet, TRAPPIST-1h, and learn more about the magnetic activity of the host star.



Eyes on the Solar System (NASA, JPL)

News stories about NASA's Eyes on the Solar System...

NASA Gives Public New Internet Tool to Explore the Solar System (NASA, JPL)

NASA Gives Public New Internet Tool to Explore the Solar System (Space Daily)

New NASA site offers solar system and time travel: Mission data from 1950 to 2050 for your viewing (Brid-Aine Parnell, The Register)


View Anyplace from Anyplace (NASA, JPL)

JRX Graphix Flash5

3D Solar System (Luke Wood)

Adjustable Gravity (LostVectorys)

Orbit Game (First Science.com)

Space Flight Simulator (Martin Schweiger)


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SLurl Inspire Space Park


Latest Headlines | Science News


© Cosma creator mehopper editor mehopper revised 2/14/2017 v.1.5

  1. ^ planet. (2015). In Merriam-Webster Online Dictionary (11th ed.). Retrieved June 21, 2015, from http://www.merriam-webster.com/dictionary/planet
  2. ^ dwarf planet. (2015). In Merriam-Webster Online Dictionary (11th ed.). Retrieved June 21, 2015, from http://www.merriam-webster.com/dictionary/dwarf+planet
  3. ^ Planetary ring. (2015). In Wikipedia, The Free Encyclopedia. Retrieved July 11, 2015, from http://en.wikipedia.org/wiki/Planetary_ring