Advertisement

Natural satellite

From Academic Kids

Missing image
Moons_of_solar_system.jpg
Moons of solar system scaled to Earth's Moon

The common noun moon (not capitalized) is used to mean any natural satellite of the other planets. There are, at least, 140 moons within Earth's solar system, and presumably many others orbiting the planets of other stars. Typically the larger gas giants have extensive systems of moons. Mercury and Venus have no moons at all, Earth has one large moon ("The Moon"), Mars has two tiny moons, and Pluto a large companion called Charon (sometimes considered to be a double planet).

Contents

Origin

Most moons are assumed to have been formed out of the same collapsing region of protoplanetary disk that gave rise to its primary. However, there are many exceptions and variations to this standard model of moon formation that are known or theorized. Several moons are thought to be captured foreign objects, fragments of larger moons shattered by large impacts, or (in the case of Earth's Moon) a portion of the planet itself blasted into orbit by a large impact. As most moons are known only through a few distant observations through probes or telescopes, most theories about them are still uncertain.

Physical characteristics

Most moons in the solar system are tidally locked to their primaries; an exception is Saturn's moon Hyperion, which rotates chaotically due to a variety of external influences. No moons have moons of their own; the tidal effects of their primaries make orbits around them unstable. However, several moons have companions in their Lagrangian points (eg, Saturn's moons Tethys and Dione).

The recent discovery of Ida's moon Dactyl confirms that some asteroids also have moons. Some, like 90 Antiope, are double asteroids with two equal-sized components.

Moons of the Solar system

The largest moons in the solar system (those bigger than about 3000 km across) are Earth's Moon, Jupiter's Galilean moons Io, Europa, Ganymede, and Callisto, Saturn's moon Titan, and Neptune's captured moon Triton. For smaller moons see the appropriate planets.

A comparative table classifying the moons of the solar system by diameter, also including a column for some notable asteroids, planets, and Kuiper belt objects.

Diameter(km) Earth Mars Jupiter Saturn Uranus Neptune Pluto Other objects
5000-6000

Ganymede Titan



4000-5000

Callisto



Mercury
3000-4000 Luna
Io

Europa






2000-3000




Triton
Pluto
1000-2000



Rhea

Iapetus
Dione
Tethys

Titania
Oberon
Umbriel
Ariel



90377 Sedna

90482 Orcus
50000 Quaoar
20000 Varuna

28978 Ixion
100-1000

Himalia

Amalthea

Enceladus

Mimas
Hyperion
Phoebe
Janus
Epimetheus
Prometheus

Miranda

Sycorax
Puck
Portia

Proteus

Nereid
Larissa
Galatea
Despina


Charon
1 Ceres

2 Pallas
3 Juno
4 Vesta
(and many others)

50-100

Thebe

Elara
Pasipha

Pandora Caliban

Juliet
Belinda
Cressida
Rosalind
Desdemona
Bianca

Thalassa

Naiad
S/2002 N 4


(Too many to list)
10-50
Phobos

Deimos

Carme

Metis
Sinope
Lysithea
Ananke
Leda
Adrastea

Siarnaq

Atlas
Helene
Albiorix
Telesto
Pan
Paaliaq
Calypso
Ymir
Kiviuq
Tarvos
Ijiraq

Ophelia

Cordelia
Setebos
Prospero
Stephano
S/1986 U 10
S/2001 U 2
S/2001 U 3
S/2003 U 3
Trinculo
S/2003 U 1
S/2003 U 2

S/2002 N1

S/2002 N 2
S/2002 N 3
S/2003 N 1


(Too many to list)
less than 10 Cruithne¹
At least 47, see Jupiter's natural satellites for a listing. Erriapo

Narvi
Skathi
Mundilfari
Suttungr
Thrymr
Pallene
Polydeuces
Methone
S/2004 S 3
S/2005 S 1




(Too many to list)

¹ It is debatable whether Cruithne counts as a real moon; it is mainly placed here for comparison's sake.

In addition to the moons of the various planets there are also over 30 known asteroid moons, asteroids that orbit other asteroids.

See also

External links

Jupiter's moons

Saturn's moons

Neptune's moons

All moons



Our Solar System
Sun | Mercury | Venus | Earth (Moon) | Mars | Asteroid belts
Jupiter | Saturn | Uranus | Neptune | Pluto | Kuiper belt | Oort cloud
See also astronomical objects and the solar system's list of objects, sorted by radius or mass
bg:Естествен спътник

bs:Prirodni satelit ca:Satllit natural cs:Přirozen satelit da:Mne de:Mond (Trabant) eo:Lunoj fr:Satellite naturel ko:위성 he:ירח hu:Hold (gitest) it:Satellite naturale ja:衛星 nl:Natuurlijke maan pl:Naturalny satelita pt:Satlite natural sl:naravni satelit fi:Kuu (yleisnimi) sv:Mne th:ดาวบริวาร zh:天然卫星

Navigation

Academic Kids Menu

  • Art and Cultures
    • Art (http://www.academickids.com/encyclopedia/index.php/Art)
    • Architecture (http://www.academickids.com/encyclopedia/index.php/Architecture)
    • Cultures (http://www.academickids.com/encyclopedia/index.php/Cultures)
    • Music (http://www.academickids.com/encyclopedia/index.php/Music)
    • Musical Instruments (http://academickids.com/encyclopedia/index.php/List_of_musical_instruments)
  • Biographies (http://www.academickids.com/encyclopedia/index.php/Biographies)
  • Clipart (http://www.academickids.com/encyclopedia/index.php/Clipart)
  • Geography (http://www.academickids.com/encyclopedia/index.php/Geography)
    • Countries of the World (http://www.academickids.com/encyclopedia/index.php/Countries)
    • Maps (http://www.academickids.com/encyclopedia/index.php/Maps)
    • Flags (http://www.academickids.com/encyclopedia/index.php/Flags)
    • Continents (http://www.academickids.com/encyclopedia/index.php/Continents)
  • History (http://www.academickids.com/encyclopedia/index.php/History)
    • Ancient Civilizations (http://www.academickids.com/encyclopedia/index.php/Ancient_Civilizations)
    • Industrial Revolution (http://www.academickids.com/encyclopedia/index.php/Industrial_Revolution)
    • Middle Ages (http://www.academickids.com/encyclopedia/index.php/Middle_Ages)
    • Prehistory (http://www.academickids.com/encyclopedia/index.php/Prehistory)
    • Renaissance (http://www.academickids.com/encyclopedia/index.php/Renaissance)
    • Timelines (http://www.academickids.com/encyclopedia/index.php/Timelines)
    • United States (http://www.academickids.com/encyclopedia/index.php/United_States)
    • Wars (http://www.academickids.com/encyclopedia/index.php/Wars)
    • World History (http://www.academickids.com/encyclopedia/index.php/History_of_the_world)
  • Human Body (http://www.academickids.com/encyclopedia/index.php/Human_Body)
  • Mathematics (http://www.academickids.com/encyclopedia/index.php/Mathematics)
  • Reference (http://www.academickids.com/encyclopedia/index.php/Reference)
  • Science (http://www.academickids.com/encyclopedia/index.php/Science)
    • Animals (http://www.academickids.com/encyclopedia/index.php/Animals)
    • Aviation (http://www.academickids.com/encyclopedia/index.php/Aviation)
    • Dinosaurs (http://www.academickids.com/encyclopedia/index.php/Dinosaurs)
    • Earth (http://www.academickids.com/encyclopedia/index.php/Earth)
    • Inventions (http://www.academickids.com/encyclopedia/index.php/Inventions)
    • Physical Science (http://www.academickids.com/encyclopedia/index.php/Physical_Science)
    • Plants (http://www.academickids.com/encyclopedia/index.php/Plants)
    • Scientists (http://www.academickids.com/encyclopedia/index.php/Scientists)
  • Social Studies (http://www.academickids.com/encyclopedia/index.php/Social_Studies)
    • Anthropology (http://www.academickids.com/encyclopedia/index.php/Anthropology)
    • Economics (http://www.academickids.com/encyclopedia/index.php/Economics)
    • Government (http://www.academickids.com/encyclopedia/index.php/Government)
    • Religion (http://www.academickids.com/encyclopedia/index.php/Religion)
    • Holidays (http://www.academickids.com/encyclopedia/index.php/Holidays)
  • Space and Astronomy
    • Solar System (http://www.academickids.com/encyclopedia/index.php/Solar_System)
    • Planets (http://www.academickids.com/encyclopedia/index.php/Planets)
  • Sports (http://www.academickids.com/encyclopedia/index.php/Sports)
  • Timelines (http://www.academickids.com/encyclopedia/index.php/Timelines)
  • Weather (http://www.academickids.com/encyclopedia/index.php/Weather)
  • US States (http://www.academickids.com/encyclopedia/index.php/US_States)

Information

  • Home Page (http://academickids.com/encyclopedia/index.php)
  • Contact Us (http://www.academickids.com/encyclopedia/index.php/Contactus)

  • Clip Art (http://classroomclipart.com)
Toolbox
Personal tools