Neptune planet has how many satellites?

Question

Neptune planet has how many satellites?

Answer 1

Neptune has 13 moons.

Names:

1. Naiad

2. Thalassa

3. Despina

4. Galatea

5. Larissa

6. Proteus

7. Triton

8. Nereid

9. Halimede

10. s****.>
11. Laomedeia

12. Psamathe

13. Neso

Answer 2

Neptune has 12.

Answer 3

Neptune has three main moons, Nereid, Proteus, and Triton, plus five smaller moons.

Answer 4

1-Naiad

2-Thalassa

3-Despina

4-Galatea

5-Larissa

6-Proteus

Answer 5

neptune planet has 02 satellites.

Answer 6

all thing concerning neptune

it has got 13 known moons

Neptune

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This article is about the planet. For other uses, see Neptune (disambiguation).

Neptune    

Neptune from Voyager 2

Discovery

Discovered by Urbain Le Verrier

John Couch Adams

Johann Galle

Discovery date September 23, 1846[1]

Orbital characteristics[2][3]

Epoch J2000

Aphelion 4,553,946,490 km

30.44125206 AU

Perihelion 4,452,940,833 km

29.76607095 AU

Semi-major axis 4,503,443,661 km

30.10366151 AU

Eccentricity 0.011214269

Orbital period 60,190[4] days

164.79 years

Synodic period 367.49 day[5]

Average orbital speed 5.43 km/s[5]

Mean anomaly 267.767281°

Inclination 1.767975°

6.43° to Sun's equator

Longitude of ascending node 131.794310°

Argument of perihelion 265.646853°

Satellites 13

Physical characteristics

Equatorial radius 24,764 ± 15 km[6][7]

3.883 Earths

Polar radius 24,341 ± 30 km[6][7]

3.829 Earths

Flattening 0.0171 ± 0.0013

Surface area 7.6408×109 km²[4][7]

14.98 Earths

Volume 6.254×1013 km³[5][7]

57.74 Earths

Mass 1.0243×1026 kg[5]

17.147 Earths

Mean density 1.638 g/cm³[5][7]

Equatorial surface gravity 11.15 m/s²[5][7]

1.14 g

Escape velocity 23.5 km/s[5][7]

Sidereal rotation

period 0.6713 day[5]

16 h 6 min 36 s

Equatorial rotation velocity 2.68 km/s

9,660 km/h

Axial tilt 28.32°[5]

North pole right ascension 19h 57m 20s[6]

North pole declination 42.950°[6]

Albedo 0.290 (bond)

0.41 (geom.)[5]

Surface temp.

   1 bar level

   0.1 bar min mean max

72 K[5]  

55 K[5]  



Apparent magnitude 8.0 to 7.78[5][8]

Angular diameter 2.2″—2.4″[5][8]

Adjectives Neptunian

Atmosphere[5]

Scale height 19.7 ± 0.6 km

Composition 80±3.2% Hydrogen (H2)

19±3.2% Helium

1.5±0.5% Methane

~0.019% Hydrogen deuteride (HD)

~0.00015% Ethane

Ices:  

Ammonia

Water

Ammonium hydrosulfide(NH4SH)

Methane (?)



Neptune (pronounced /ˈnɛptjuːn/[9], AmE: [ˈnɛp·tuːn] (help·info)) is the eighth and farthest planet from the Sun in the Solar System. It is the fourth largest planet by diameter, and the third largest by mass. Neptune is 17 times the mass of Earth and is slightly more massive than its near-twin Uranus, which is 15 Earth masses and less dense.[10] The planet is named after the Roman god of the sea. Its astronomical symbol is , a stylized version of the god Neptune's trident.

Discovered on September 23, 1846,[1] Neptune was the first planet found by mathematical prediction rather than regular observation. Unexpected changes in the orbit of Uranus led astronomers to deduce the gravitational perturbation of an unknown planet. Neptune was found within a degree of the predicted position. The moon Triton was found shortly thereafter, but none of the planet's other 12 moons were discovered before the 20th century. Neptune has been visited by only one spacecraft, Voyager 2, which flew by the planet on August 25, 1989.

Neptune is similar in composition to Uranus, and both have different compositions from those of the larger gas giants Jupiter and Saturn. As such, astronomers sometimes place them in a separate category, the "ice giants". Neptune's atmosphere, while similar to Jupiter and Saturn in being composed primarily of hydrogen and helium, contains a higher proportion of "ices" such as water, ammonia and methane, along with the usual traces of hydrocarbons and possibly nitrogen.[11] In contrast the interior of Neptune is mainly composed of ices and rocks like that of Uranus.[12] Traces of methane in the outermost regions, in part, account for the planet's blue appearance.[13]

Neptune has the strongest winds of any planet in the solar system, measured as high as 2100 km/h.[14] At the time of the 1989 Voyager 2 flyby, its southern hemisphere possessed a Great Dark Spot comparable to the Great Red Spot on Jupiter. Neptune's temperature at its cloud tops is usually close to −218 °C (55.1 K), one of the coldest in the solar system, due to its great distance from the Sun. The temperature in Neptune's centre is about 7,000 °C (7,270 K), which is comparable to the Sun's surface and similar to most other known planets. Neptune has a faint and fragmented ring system, which may have been detected during the 1960s but was only indisputably confirmed by Voyager 2.[15]

Contents [hide]

1 History

1.1 Discovery

1.2 Naming

1.3 Status

2 Composition and structure

2.1 Internal structure

2.2 Atmosphere

2.3 Magnetosphere

2.4 Planetary rings

3 Climate

3.1 Storms

3.2 Internal heat

4 Orbit and rotation

4.1 Orbital resonances

5 Formation and migration

6 Moons

7 Observation

8 Exploration

9 See also

10 References

11 Further reading

12 External links



[edit] History

[edit] Discovery

Main article: Discovery of Neptune

Galileo's drawings show that he first observed Neptune on December 28, 1612, and again on January 27, 1613; on both occasions, Galileo mistook Neptune for a fixed star when it appeared very close—in conjunction—to Jupiter in the night sky.[16] Hence he is not credited with Neptune's discovery. During the period of his first observation in December 1612, it was stationary in the sky because it had just turned retrograde that very day. This apparent backward motion is created when the orbit of the Earth takes it past an outer planet. Since Neptune was only beginning its yearly retrograde cycle, the motion of the planet was far too slight to be detected with Galileo's small telescope.[17]

In 1821, Alexis Bouvard published astronomical tables of the orbit of Uranus.[18] Subsequent observations revealed substantial deviations from the tables, leading Bouvard to hypothesize that an unknown body was perturbing the orbit through gravitational interaction. In 1843, John Couch Adams calculated the orbit of a hypothesized eighth planet that would account for Uranus' motion. He sent his calculations to Sir George Airy, the Astronomer Royal, who asked Adams for a clarification. Adams began to draft a reply but never sent it and did not aggressively pursue work on the Uranus problem.[19][20]



Urbain Le Verrier, the mathematician who codiscovered Neptune.In 1845–46, Urbain Le Verrier, independently of Adams, rapidly developed his own calculations but also experienced difficulties in encouraging any enthusiasm in his compatriots. In June, however, upon seeing Le Verrier's first published estimate of the planet's longitude and its similarity to Adams's estimate, Airy persuaded Cambridge Observatory director James Challis to search for the planet. Challis vainly scoured the sky throughout August and September.[21][22]

Meantime, Le Verrier by letter urged Berlin Observatory astronomer Johann Gottfried Galle to search with the observatory's refractor. Heinrich d'Arrest, a student at the observatory, suggested to Galle that they could compare recently drawn chart of the sky in the region of Le Verrier's predicted location with the current sky to seek the displacement characteristic of a planet, as opposed to a fixed star. The very evening of the day of receipt of Le Verrier's letter, Neptune was discovered, September 23, 1846, within 1° of where Le Verrier had predicted it to be, and about 12° from Adams' prediction. Challis later realized that he had observed the planet twice in August, failing to identify it owing to his casual approach to the work.[21][23]

In the wake of the discovery, there was much nationalistic rivalry between the French and the British over who had priority and deserved credit for the discovery. Eventually an international consensus emerged that both Le Verrier and Adams jointly deserved credit. However, the issue is now being re-evaluated by historians with the rediscovery in 1998 of the "Neptune papers" (historical documents from the Royal Observatory, Greenwich), which had apparently been misappropriated by astronomer Olin J. Eggen for nearly three decades and were only rediscovered (in his possession) immediately after his death.[24] After reviewing the documents, some historians now suggest that Adams does not deserve equal credit with Le Verrier. Since 1966 Dennis Rawlins has questioned the credibility of Adams's claim to co-discovery. In a 1992 article in his journal Dio he deemed the British claim "theft".[25] "Adams had done some calculations but he was rather unsure about quite where he was saying Neptune was", said Nicholas Kollerstrom of University College London in 2003.[26][27]

[edit] Naming

Shortly after its discovery, Neptune was referred to simply as "the planet exterior to Uranus" or as "Le Verrier's planet". The first suggestion for a name came from Galle, who proposed the name Janus. In England, Challis put forward the name Oceanus.[28]

Claiming the right to name his discovery, Le Verrier quickly proposed the name Neptune for this new planet, while falsely stating that this had been officially approved by the French Bureau des Longitudes.[29] In October, he sought to name the planet Le Verrier, after himself, and he was patriotically supported in this by the observatory director, François Arago. However, this suggestion met with stiff resistance outside France.[30] French almanacs quickly reintroduced the name Herschel for Uranus, after that planet's discoverer Sir William Herschel, and Leverrier for the new planet.[31]

Struve came out in favour of the name Neptune on December 29, 1846, to the Saint Petersburg Academy of Sciences.[32] Soon Neptune became the internationally accepted name. In Roman mythology, Neptune was the god of the sea, identified with the Greek Poseidon. The demand for a mythological name seemed to be in keeping with the nomenclature of the other planets

Answer 7

Neptune has 11 known satellites.