Shop Windows to the Universe

Our Glaciers: Then and Now activity kit helps you see the changes taking place in glaciers around the world. See all our activity kits and classroom activities.

Quickie Questions - Other Solar System Stuff - Neptune and Its Moons

Date Answered Questioner (age, location) Question Answer

January 27, 2010cindy (age 12, n.c.) what is neptunes circumfrence In geometry, circumference is the curved line that encloses a curved plane figure. This concept is not applied to shapes with volume. There are other data that are useful to describe a planet. For Neptune: Diameter: 49 493 km (30 760 miles). Mass: 102.4 x 1024 kilograms (17.2 x Earth's mass).
December 17, 2009Samantha (age 11, Sd) can people live on Neptune? Neptune? hmmm, there are many problems with Neptune. It is far away from the Sun (2.82 billion miles!!) and there is very little Sun energy that reaches there. It is a gas Giant, and the Giant planets do not have the same kind of layers inside that the Earth-like planets do. Their evolution was quite different, and they have much more gas and ice inside. Neptune's interior make-up is primarily methane ice, just as Uranus' is. So, it would be hard for humans to live in this planet!
October 19, 2009abc (age 123, london) what colour is neptune The color of Neptune is siad to be a bright azure blue. See our page for more details.
October 19, 2009kevin (age 9, Florda USA) what dose neptunes surface look like The Giant planets do not have the same kind of layers inside that the Earth-like planets do. Their evolution was quite different than that of the Earth-like planets, and they have much more gas and ice inside. Neptune's interior, in particular, is made of primarily methane ice, just as Uranus' is.
October 13, 2009Hershal (age 54, New Zealand) the details on the moons of Neptune, when were they compiled? or what is the source? thanks. Our page Neptune's Moons and Rings and the links and tables therein offer lots of information...
September 28, 2009Ajay (age 31, India) Tell me distance between Earth & Neptune Neptune's minimum distance from Earth is 4.3 billion km (2.68 billion miles).
July 27, 2009ruby (age 10, ILLNIOS) why is naptune blue Neptune, the eighth and furthest planet from the Sun, is a very cold place. Its bluish color is caused by small amounts of methane gas in its atmosphere.
July 22, 2009bella (age 76, hillside) Why you can't see Neptune with a telescope? Under the right conditions it ispossible see Neptune with a telescope. It is known that Galileo observed Neptune with his rustic telescope.
May 29, 2009tiffany (age 12, Alabama/U.S.A.) what is the highs adn lows at surface, on Neptune? Neptune is a giant gas planet, which interior is primarily methane ice. There is no solid surface in Neptune.
May 12, 2009Richard (age 10, VA) How do Neptune's rings affect Neptune? The mass of Neptune's rings is low when compared to some of our system moons. I don't think they affect Neptune other than a very low gravitational pull.
April 28, 2009mya (age 14, minnesota/USA) What is neptune's gravity comapared to earth? Neptune's surface gravity is 11 m/s2, 1.12 times Earth's gravity.
March 17, 2009Danielle (age 12, California) Does Triton have plate tectonics and if it does can you please send me information on it. Please, visit our web page Inside Triton and links therein for information on this topic.
March 4, 2009ally (age 8, texas) what is neptune's atmosphere made out of? The composition of Neptune clouds is thought to be methane molecules.
February 20, 2009Cameron (age 9, Texas/usa) What to wear to Neptune There would be many factors to take in account. Just to mention a couple of them: With temperatures of -210º C ( -346º F) and with an atmosphera thought to be form of methane molecules, whatever you would be using would have to protect you from the extreme cold and supply you with breathable air. pressures of about 1-3 bars (
February 17, 2009Maggie (age 12, Illinois) What's the circumference of Neptune? :(
U r smart, please tell me!!:)
Neptune's diameter is 49 493 km (30 760 miles).
February 6, 2009Terri (age 15, virginia beach va) what made the scientist think that Neptune must exist? After the discovery of Uranus, scientists were having trouble figuring out the planet's orbit. They realized that there must be another planet farther out than Uranus. They were right! French astronomer Leverrier and English astronomer John Couch Adams made the mathematical calculations of where Neptune should be and German astronomer Johann Galle observed it.
January 23, 2009Lizzette (age 13, ) What is Neptune orbit? The orbit of Neptune can be described by the following parameters: Revolution Period about the Sun: 165 years Minimum Distance from Sun: 4.46 billion km (2.77 billion miles) Maximum Distance from Sun: 4.54 billion km (2.82 billion miles) Orbital Semimajor Axis: 30.07 AU (Earth=1 AU)
January 14, 2009namiao (age 9, New York) how long is a day on Saturn A day uin saturn is 10.67 hrs, a year is 29.5 Earth years.
August 18, 2008eddie (age 9, FL/USA) what are the high and low tempreatures of neptune? Neptune temperature at cloud Tops: -210oC ( -346oF).
August 18, 2008eddie (age 9, FL/USA) what is neptunes distance form the sun? For Neptune: Minimum Distance from Sun: 4.46 billion km, Maximum Distance from Sun: 4.54 billion km
July 8, 2008danielle (age 13, london) how much sun does neptune get ? Neptune, the farthest known planet of our solar system, is located about 30 times farther away from the Sun than Earth is. Only about one thousandth of the sunlight received by our planet reaches Neptune. Yet, the small amount of sunlight Neptune does receive significantly affects the planet's atmosphere. Please, see this article for more information.
July 7, 2008kayleigh (age 9, tennessee, usa) How far away is neptune from the earth? Neptune's minimum distance from Earth is 4.3 billion km (2.68 billion miles).
July 7, 2008kayleigh barnes (age 9, tennessee, usa) How far away is neptune from the earth? Neptune's minimum distance from Earth is 4.3 billion km (2.68 billion miles).
June 30, 2008Cache (age 12, Maryland) How does Saturn look like far away and up close? Please, visit our web page Neptune Image List.
April 30, 2008ananth (age 13, New Jersey) how big is neptune? Neptune's diameter is 49,493 km (30,760 miles), and its mass is 102.4x1024 kilograms (17.2 x Earth's). More information on this planet in our webpage Neptune Statistics.
April 21, 2008veronica (age 12, ill) How far is neptune from earth? Distance between Neptune and Earth: Minimum = 4305.9 x 106 km Maximum = 4687.3 x 106 km
April 21, 2008veronica (age 12, ill.grayslake) How far is neptune from earth? Distance between Neptune and Earth: Minimum = 4305.9 x 106 km Maximum = 4687.3 x 106 km
April 2, 2008Chelsea (age 11, north Carliona) What is Neptune Diameter? Neptune's diameter is 49,493 km (30,760 miles).
March 7, 2008kyle (age 11, albany NY) Who found neptune??? Neptune was first predicted mathematically by John Couch Adams and Urbain Jean Joseph Le Verrier. The observers Johann Gottfried Galle and Heinrich d' Arrest found Neptune near the predicted location.
March 4, 2008sherelle (age 15) if a object weighed 100 pounds on the earth, what would it weigh on neptune? Surface gravity on Neptune is 11 m/s2 (1.12 x Earth's). Any object here would be 1.12 heavier that on Earth (the object in your question will weight 112 lbs.)
March 4, 2008sherelle (age 15, country) What are the names of neptune moons? Neptune's moons are (from largest to smallest): Triton, Proteus, Nereid, Larissa, Galatea, Despina, Thalassa, Naiad, S/2002 N4, S/2002 N1, S/2002 N2, S/2002 N3, and S/2003 N1.
February 8, 2008sami (age 10, nc/usa) what sort of weather is on neptune Highs in Neptune's upper atmosphere are about -150 Centigrade, with winds ranging about 900 miles per hour near the equator. The weather differs between the two hemispheres of Neptune. The overall blue color of Neptune is caused by methane gas preferentially absorbing red light, while the yellow spots are the highest clouds.
January 21, 2008belinda (age 13, australia) how long does it take for neptune to revolve around the sun? For Neptune, a full revolution around the Sun takes 165 Earth's years.
January 10, 2008Heaven (age 8, Oregon) How much would we weigh on Neptune? say if I weighed 100 pounds? Neptune's gravity is 11 m/s2 (1.12 x Earth's), so your weight will be also 1.12 times your weight on Earth, in your case it would be 112 punds.
December 20, 2007Stevie (age 15, usa) how many miles away is neptune from the sun? For Neptune: Minimum Distance from Sun: 4.46 billion km (2.77 billion miles) Maximum Distance from Sun: 4.54 billion km (2.82 billion miles)
August 17, 2007Ashley (age 11, fl) Why is Neptuune cold? Effectively, Neptune, with temperatures at cloud tops of -210o C (-346o F), is a very cold planet. This is mainly due to its distance to the Sun. At its closest point (perihelion), Neptune is at 4.46 billion km (2.77 billion miles) from the Sun, a huge distance. (For example, earth’s minimum distance to the Sun is 146 million km (91 million miles).
July 25, 2007Camel (age 15, Sydney) can you actually land on neptune? The Giant planets do not have the same kind of layers inside that the Earth-like planets do. Their evolution was quite different than that of the Earth-like planets, and they have much more gas and ice inside. In Neptune, the gas part of the planet is much bigger than the rocky part. That is because the amount of gas and ice which came to Neptune in the beginning, depended upon where Neptune was in the original solar cloud. So, there is not an easily accesible solid surface to land in Neptune.
July 17, 2007Saija (age Ten, MA) I'm doing some reserch on Neptune, and I want to know the exact color of blue that Neptune is, could you please help me? This NASA web page shows a True-Color Image of Neptune.
July 17, 2007Saija (age Ten, MA) I'm doing some reserch on Neptune, and I want to know the exact color of blue that Neptune is, could you please help me? This NASA we page shows a True-Color Image of Neptune.
July 17, 2007Callan (age 9, Ma. USA) I just do not get this question please help.
It takes Neptune 60,190 days to orbit the sun. This means that one year on Neptune is actully_____ long. That is as many as _________Earth days?
Neptune's year (its revolution period about the Sun) is about 165 Terrestrial years or 60 190 Terrestrial days.
July 5, 2007JOE (age 15, CALIFORNIA/UNTIED STATES) WHAT IS THE SURFACE TEMP. OF NEPTUNE? The values we have been able to obtain from Neptune correspond to the temperature at cloud tops: -210 oC ( -346 oF).
July 2, 2007Fannya (age 13, CA) why neptune is blue? Neptune's atmosphere is mostly hydrogen and helium with a small amount of methane. Its blue color is largely the result of absorption of red light by methane in the atmosphere.
July 2, 2007calandra (age 15, az) how is the surface description on neptune? The Giant planets do not have the same kind of layers inside that the Earth-like planets do. Their evolution was quite different than that of the Earth-like planets, and they have much more gas and ice inside. Neptune's interior make-up is primarily methane ice, just as Uranus' is. Motions in the interior of Neptune help form the magnetosphere of Neptune. Heat generated within Neptune helps form the unusual winds of the atmosphere.
July 2, 2007calandra (age 15, az) how is the surface description on neptune? The Giant planets do not have the same kind of layers inside that the Earth-like planets do. Their evolution was quite different than that of the Earth-like planets, and they have much more gas and ice inside. Neptune's interior make-up is primarily methane ice, just as Uranus' is. Motions in the interior of Neptune help form the magnetosphere of Neptune. Heat generated within Neptune helps form the unusual winds of the atmosphere.
July 2, 2007cheyenne (age 12, north carolina) how old is neptune? Neptune is as old as the Sun: 4.5 billion years.
May 30, 2007alli (age 10, ) what is the god of neptune? Neptune was the name that ancient Romans gave to the Greek god of the sea and earthquakes, Poseidon. He was the brother of Jupiter (Zeus) and of Pluto (Hades). More information in our web page Neptune.
May 21, 2007Jessica (age 17, IN) who named neptune and why did they name it that name? After the discovery of Uranus, scientists were having trouble figuring out the planet's orbit. They realized that there must be another planet farther out than Uranus. They were right! French astronomer Leverrier and English astronomer John Couch Adams made the mathematical calculations of where Neptune should be and German astronomer Johann Galle observed it. More information in our web page Discover Neptune.
May 10, 2007kadie (age 10, usa) how many moons does neptune have? Neptune has 13 moons: Despina, Galatea, Larissa, Naiad, Nereid, Proteus, S/2002 N1, S/2002 N2, S/2002 N3, S/2002 N4, S/2003 N1, Thalassa, Triton.
April 13, 2007ABHAY (age 17, INDIA) WHAT IS THE DIFFERENCE BETWEEN THE TEMPERATURE OF NEPTUNE & URANUS Uranus, Temperature at Cloud Tops: -200oC ( -328oF) Neptune, Temperature at Cloud Tops: -210oC ( -346oF)
March 31, 2007 (age , ) The International Astronomical Union (IAU) redefined "planet" in the Solar: A planet is a celestial body that - is in orbit around the Sun, - has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and - has cleared the neighborhood around its orbit. Neptune (and the rest of the planets, except Pluto) fulfills this definition.
March 31, 2007sonya (age , ) The orbit of Neptune is most of the time between the orbit of Uranus and Pluto. Its minimum distance from the Sun is 4.46 billion km (2.77 billion miles) and itsa maximum is 4.54 billion km (2.82 billion miles).
March 26, 2007Audrey (age 8, Omaha) How big is Neptune compared to the other planets Neptune has a diameter of 49 493 km (30,760 miles) and a mass = 102.4x1024 kilograms (17.2 x Earth's). For a comparison with other planets, see our Table of Planets.
March 26, 2007Audrey (age 8, Omaha) How big is Neptune compared to the other planets Neptune has a diameter of 49 493 km (30,760 miles)and a mass = 102.4x1024 kilograms (17.2 x Earth's). For a comparison with other planets, see our Table of Planets.
March 26, 2007Laura (age 18, Arizona) what is the mythological origin of the name Neptune? Neptune was the name that ancient Romans gave to the Greek god of the sea and earthquakes, Poseidon. He was the brother of Jupiter (Zeus) and of Pluto (Hades). After the defeat of their father Saturn (Cronos), the three brothers divided the world in three parts to be ruled by one of the three brothers. Jupiter took the sky, Neptune the sea and Pluto the underworld.
February 13, 2007Ka (age 7, Hong Kong) Do Neptune have oxygen? The atmosphere of Neptune contains more of the complex molecules such as methane gas, ethane gas, acetylene, and diacetylene. These constituents collectively are known as "hydrocarbons". For more information about thisplanet visit our web page Neptune Atmospheric Composition.
February 12, 2007Angelina (age 10, C.A. U.S.A.) How long is a day on Neptune? Neptune's rotation period about its axis (lenght of the day) is 17.24 hrs.
January 22, 2007Harmony (age 10, VA ,U.S.A.) How are Uranus and Neptune alike? Uranus's and Neptune's interiores are primarily made of methane ice.
Motions in the interior of both planets help form their respective magnetosphere. Heat generated within them helps form the unusual winds of their atmosphere.
For more information, visite our web pages Uranus and Neptune.
January 22, 2007Harmony (age 10, VA ,U.S.A.) How are Uranus and Neptune alike? Uranus's and Neptune's interiores are primarily made of methane ice. Motions in the interior of both planets help form their respective magnetosphere. Heat generated within them helps form the unusual winds of their atmosphere. For more information, visite our web pages Uranus and Neptune.
December 20, 2006Sabrina (age 11, Colorado) what is the greak myth for Neptune? Taken from our page Myths About Neptune: Many features of the Earth are named after mythological figures. An example is the story of Galatea's love for a young beautiful shepherd called Acis. He was the son of Pan.Galatea lived in the sea surrounding the island of Sicily where she met several times one of the Cyclopes, the monstrous one-eyed Polyphemus. Polyphemus was in love with Galatea and was unable to control his jealousy of Acis. Once Polyphemus caught Galatea and Acis asleep on a grassy mound. He killed the small shepherd with a huge rock. Acis' blood formed a small stream on the ground. Heartbroken, Galatea turned it into a stream of water that bears Acis' name. Because Galatea was a sea-nymph and attendant of the sea-god Poseidon, her name had been given to one of the moons of the planet Neptune.
December 1, 2006Katie (age 13, Arnold, MO) DO YOU KNOW WHAT THE TEMPERTURE ON NEPTUNE IS WITHOUT ME HAVING TO DO THE MATH? The temperature at Neptune’s cloud tops is -210o C (-346o F)
November 30, 2006Tiffany (age 11, NC) What Is The Temputure In Celcius On Neptune The temperature at the cloud tops of Neptune is -210 C ( -346 F). For more interesting facts about Neptune visit this page.
November 22, 2006tomlin (age 20, usa) what is Neptune's orbit time? The period of rotation of Neptune about its axis (length of Neptune’s day) is 17.24 hrs. It’s period of revolution around the Sun is 165 Earth years
June 6, 2001 Jill (9, Michigan, USA) For how many years do Neptune and Pluto switch orbits? Pluto was the eighth planet from the Sun from February 7th, 1979, through February 11, 1999 (so for about 20 years!). Now, Pluto will remain the ninth planet through the 23rd century.
June 6, 2001 LaCrissa (13, Ohio, USA) How many satellites does Neptune have? Neptune has 8 moons that we know about...
October 9, 2000 Chong (age 10, Singapore) Which planet is known as the blue planet? Though the Earth has some blue in it too, Neptune looks really blue because of the methane gas in its atmosphere.
May 12, 2000 Jessica (age 14, Wisconsin, USA) What is the size of Neptune's 'Great Dark Spot?' The Great Dark Spot on Neptune is about the size of the Earth, or 8,000 miles in diameter.
March 3, 2000 Jeremy (age 11, Virginia, USA) Is there any evidence of water on the planet Neptune? Neptune has no water to speak of, it's mostly made of methane. Triton, one of its moons, does possibly have some water however.
February 15, 2000 Jessica (age 9, Kansas, USA) what is Neptune made of? Neptune's interior make-up is primarily methane ice. The composition of Neptune clouds is thought to be methane as well, along with ethane gas, acetylene, and diacetylene.
December 24, 1999 Ashley(--) Please advise me of how Neptune moves & spins Because Pluto's orbit is elongated, sometimes Neptune is the outermost planet of the solar system. This was the case from 1979 to the beginning of 1999: Neptune is currently the 8th planet, as it usually is. It has a rotation period (day) of 17 hrs, 6 mins, and an orbital period (year) of 165 Earth years. For more information, you might try our Neptune Statistics page.
August 2, 1999 Amy (age 12, California) Is it true that Netune is also the farthest planet because it's orbit crosses with pluto's? Neptune became the last planet on February 7th 1979, but But Pluto regained the title of last planet on February the 11th of this year (1999). The reason for this flip flop is Pluto's eccentric orbit which caries the tiny frozen world between 7.4 and 4.4 billion km's away from the Sun. Pluto will remain the ninth planet for over two hundred years.
May 11, 1999 Darcey (age 14, Indiana,USA) Okay I'm having trouble doing this project on Neptune. I have to try and get people to visit my planet which is Neptune. This is just for fun and you have to use your imagination. Well I've been looking for soooo long and trying to figure out what's so gr eat about this planet, and I can't find one thing that would make me want to visit this planet. Can you please help me? How about using the Great Dark Spot? Maybe you could turn it into a tourist attraction like an amusement park!
November 12, 1998 Kimberly (age 13, Pennsylvania, USA) Why is the planet Neptune called the 'Mathematician Planet'? Neptune is called the Mathematicians's Planet because it was discovered mathematically. John Couch Adams predicted its existence, and in 1846 in Berlin, it was discovered.
August 5, 1998 Lisa (Age 13, Tasmania) What is the Great Dark Spot on Neptune? The Great Dark Spot of Neptune is thought to be a hole in the thick methane clouds of Neptune.
May 16, 1998 Simon (age 12, Pennsylvania, USA) What is the average surface temperature of Io, Ganymede, Callisto, Phobos and Triton? The average temperature of Io is 130K. The average temperatures for Ganymede, Callisto, Triton are 117K, 126K and 34.5K respectively. As far as I know, the average temperature of Phobos is not yet known.
May 5, 1998 Khyla (age 16, Michigan, U.S.A.) Why does the planets of Neptune and Ploto interchange inside of each other's orbits? Also is it true that Pluto isn't a real planet? The center of Pluto's orbit is not close to the Sun. This causes the orbits to overlap each other. Pluto is generally considered a true planet now, but some astronomers still think it is not because it is so small and its orbit is so strange.
January 30, 1998 Christopher (age 9, Iowa, USA) How did Neptune's moon Triton get its color? Neptune's moon Triton is pink for the most part (sometimes a dark pink, sometimes lighter). It's thought that this color is produced when light interacts with the methane in Triton's atmosphere and surface.
January 29, 1998 Katie (age 14, Michigan, USA) In my science class, we learned that Neptune radiates approximately 2.7 time the amount of energy it receives from the sun. How can the sunlight go to Neptune (which has a temperature of ~'215 degrees C) and have more energy radiate back than it recei ves from the sun? Energy from the Sun dissipates with distance and it's a long way to Neptune, so that is one reason why Neptune can radiate more energy than it receives from the Sun. Another reason is that Neptune, Jupiter, Saturn, and Uranus are actually very warm p lanets, in fact they generate their own heat. Earth generates its own heat too, but not as much as these giant planets, and certainly not as much as the Sun. Some of the Neptune's energy comes from the fact that it is still forming, and that means it is still collapsing in on itself. This process releases energy.


Last modified March 4, 2008 by Eduardo Araujo-Pradere.

Shop Windows to the Universe Science Store!

Learn about Earth and space science, and have fun while doing it! The games section of our online store includes a climate change card game and the Traveling Nitrogen game!

Windows to the Universe Community

News

Opportunities


Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF