What are the names of the earth, moon, sun, and solar system? (Beginner) - Curious About Astronomy? Ask an Astronomer What are the names of the earth, moon, sun, and solar system? (Beginner) (Beginner) >" onclick="window.open(this.href,'win2','status=no,toolbar=no,scrollbars=yes,titlebar=no,menubar=no,resizable=yes,width=640,height=480,directories=no,location=no'); return false;" rel="nofollow"> All the other planets (Mercury, Venus, Mars, etc.) have names. What's the Earth's name? The other moons in the solar system have names too (Phobos, Io, Titan, etc.). What's our moon's name? Our galaxy has a name: the Milky Way. So what's the name of our solar system? The name of our planet is the Earth. The name of our moon is the Moon. The name of our solar system is the Solar System. Notice that I capitalize them, because when used as names, they are proper nouns.

This also helps us distinguish between the planet Earth and earth (meaning soil), between the Earth's Moon and moon (meaning the natural satellite of a planet), and between our Solar System and any other solar systems (since any system containing a star and a planet or a planet-forming disk can be called a solar system.) This is the English language usage approved by the International Astronomical Union , the body in charge of naming celestial objects. It may seem odd that these important objects don't have names, but if you think about it, it just reinforces their importance. For example, the Moon is the Moon, not just any moon. It requires no other name, because it's the most important moon! You may read or hear people using Luna for the Moon, or Terra or Gaia for the Earth, or Sol for the Sun, but in English-speaking countries, these are poetic terms, often seen in science fiction stories, but not used by astronomers in scientific writing. In some countries where Romance languages are spoken, these terms are the official names. It's also interesting to note that most astronomers do not call our galaxy the Milky Way in technical writing--they call it the Galaxy. This page was last updated June 28, 2015.

NASA - Another Planet in the System? Another Planet in the System? 12.06.05 "My Very Educated Mother Just Showed Us Nine Planets -- plus one." That's right. Scientists have recently discovered what many are calling the 10th planet. Scientists at the California Institute of Technology, also known as Caltech, in Pasadena, Calif., saw what may be another planet in our solar system. Their research was sponsored, in part, by NASA. They made the announcement of the new planet earlier this year. Until it gets an official name, the planet is being called 2003 UB313. Image to right: The Samuel Oschin Telescope photographed the 10th planet. Credit: Danner/Hogg Caltech Is It a Planet or Not? Some people are not sure if the object is a planet. So, how do we know? The funny thing about deciding if an object is a planet is that there is no scientific definition for "planet." We have always called the large objects that orbit our sun "planets." Seventy-five years ago, Pluto was discovered and we called it a planet. We know that this new object is larger than Pluto.

So, if Pluto is a planet, 2003 UB313 must be too, its discoverers say. What Do We Know About This Object? Scientists can make an educated guess about the size of 2003 UB313 by studying its brightness, its distance from the sun and by determining which telescopes can or cannot see it. They can also tell what the object is made of using spectroscopes, which break up reflected light into its different colors, like a prism. Way, Way Out Scientists measure the distances between planets in our solar system in astronomical units (AU). One AU is the distance from the sun to the Earth, or about 150 million kilometers (93 million miles). The"new planet" is 97 AUs from the sun. That is more than twice the distance to Pluto. It is currently the farthest known object in the solar system. It orbits the sun in the Kuiper (ky-per) Belt. This is the cold region beyond the planet Neptune. From 97 AUs, the sun would look like the brightest star in the night sky. There would be no daylight. Can I See It?

If you have a really large telescope in your backyard, you would be able to see 2003 UB313. Image to left: The sun would look like the brightest star in the sky from this planet. Credit: Robert Hurt, IPAC The telescope that was used to find it has a mirror that collects light. That mirror is 1.2 meters (48 inches) across. It can collect about 360,000 times the amount of light collected by your eye. The Name Game Compared to names like Mars or Venus, 2003 UB313 may sound strange. How will you remember that name for a test? Relax, this is only a temporary name. The name will change when people decide just what the object is. So what does 2003 UB313 mean? The first four digits tell us the year of discovery. The object was first photographed in 2003, though scientists didn't find it in the photographs until 2005. The first letter indicates which half of which month the object was found. All letters of the alphabet are used except "I" and "Z." A "T" would represent the period from Oct.

1-15. The "U" in UB313 means that it was found during the period Oct. 16-31. The second letter and subscript digits tell us the order in which the object was found during that period of time. An “A” would be given to the first object found, a "B" to the second, and so on. This time, all letters are used except "I." What happens once 25 objects have been found and the end of the alphabet is reached? The 26th object starts over with the letter "A" followed by a subscript numeral "1" … A-Z represent objects 1-25 A2-Z2 represent objects 51-75 … and so on. The number 313 tells us that there were many more than 75 objects found during this two-week period. Can you figure out how many objects were found before 2003 UB313? B313 means that during that half- Tenth Planet Fast Facts Telescope: Samuel Oschin Telescope, San Diego, Calif. First Photographed: Oct. 21, 2003 Noticed in photos: Jan.

8, 2005 Discovery announced: July 29, 2005 month period, astronomers used all 25 letters 313 times, and then used the letters A and B again. Since 25 times 313 is 7,825, adding two more (for the extra A and B) makes a total of 7,827. Almost all of these were small asteroids in the Main Asteroid Belt between the orbits of Mars and Jupiter. There are hundreds of thousands of asteroids there. Since 2003 UB313 is a temporary name, who actually gets to name the planet? The scientists who discovered it have selected a name, but the International Astronomical Union will make the final decision. Something to Think About Many people say a sentence, called a mnemonic, such as "My Very Educated Mother Just Showed Us Nine Planets" in order to remember the order of planets starting from the sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. If 2003 UB313 is dubbed a planet, what new sentence will we use to remember it?

Denise Miller/NASA Educational Technology Services Origins of Planet Names: A Quick Guide | Wyzant Resources Websters Word Histories (Springfield, Massachusetts: Merriam-Webster Inc., Publishers, 1989), p. 368. A medical term for a tree struck by blight comes from an old belief that malignant aspects of the planets caused death and suffering on earth. When plants and animals died or fell ill for no apparent reason, they were said to be planet-struck. The term is first recorded in 1600. Source of Information: Encyclopedia of Word and Phrase Origins by Robert Hendrickson (New York: Facts On File, Inc., 1997), p. 530. The ancients were convinced that there were just seven planets including the: Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn. It was also strongly believed that these planets were particularly important in the affairs of mankind. The astrological study of their positions among the stars at the moment of ones birth was supposed to give information about his/her fate.

The general character of a person was thought to be determined by which planet she/he was born under according to the calculations of astrologers, and such superstitions continue in modern times. Each of the seven planets was also believed to have a special influence over its designated day of the week: First day, Sol or the Sun; Second day, Luna or the Moon; Third day, Mars; Fourth day, Mercury; Fifth day, Jupiter; Sixth day, Venus; and the Seventh day, Saturn. The alchemists of the Middle Ages noted that there were seven planets and seven metals which were matched with the planets. The seven metals presented by the alchemists and matched with the planets include (in English): gold (Sun), silver (Moon), copper (Venus), iron (Mars), tin (Jupiter), lead (Saturn), and quicksilver (Mercury). Much more has been learned about the planets since 1977 because of the flights of Voyagers 1 and 2 (you may see a summary of the subject with a simple click). Planets with and without Moons in their Orbital Orders from the Sun Neptune , thirteen satellites. Pluto , four moons, the largest being Charon.

The planets are illustrated below and links are available for more details about their myths, symbolisms, and scientific information. Just click on the image of your choice for further details. Apollo , the Sun god, and the center of our solar-planetary system. Mercury , messenger of the Roman gods (first planet from the sun). Venus , goddess of love and beauty, springtime and flowers (second planet from the sun). Gaea , Earth goddess (ancient Greeks thought of her as Terra Mater) Earth Mother (third planet from the sun). Diana, or Luna , Roman goddess of the Moon, animals, and hunting (earths moon). Pluto , Greek god of wealth, ruled the dark underworld of myth (ninth planet from the sun). Other terms related to the word "planet" planetarian: 1. Belonging to or connected with a planet or planets; planetary. 2. An astrologer. 3. An inhabitant of a planet. planetarium: 1. A building usually with a domed ceiling onto which movable images of the stars, planets, and other objects seen in the night sky are projected for an audience. 2.

A model of the solar system, often a working model showing how the planets revolve around the Sun. planetarily: After the manner of a planet; figuratively, with uncertain recurrence. planetary: 1. Relating to, belonging to, involving, or typical of planets. 2. Involving or relating to the whole earth, all the people or countries of the world, or a large proportion of them. planetesimal: 1. A small body that is the precursor of a planet in the early stages of solar system development, or the fragmented result of a cataclysmic collision between a planet and another celestial body. 2. A small rocky celestial object thought to have orbited the Sun in the early stages of the solar system before coalescing with others to form the planets. 3. A small solid body following a planetary orbit; a miniature planet. planetical: 1. Of or pertaining to the planets; planetary. 2. Wandering, roving, vagrant. planeticose: Given to wandering. planetography: A description of the physical features of a planet. planetoid, planetoidal: 1.

A branch of astronomy that studies the origin and composition of the planets and other solid bodies in the solar system such as comets and meteors; asteroid. 2. A body resembling a planet; a name sometimes given to the minor planets or asteroids. 3. Of or belonging to the astroids. planetolatry: Idolatrous worship of the planets. planetologist: 1. Someone who studies the planets including their origins and compositions. 2. An expert or specialist in planetology. planetology: A branch of astronomy dealing with planets and satellites, including their surface features, structures, chemical compositions, and atmospheres. planisphere: A circular star map drawn for a given latitude, having a rotating mask that shows which constellations are visible at any time and date in the year. superplanetary: Above the surface of a planet.

Astronomers discover new dwarf planet and possible super-Earth in our Solar System - ExtremeTech Astronomers discover new dwarf planet and possible super-Earth in our Solar System Astronomers discover new dwarf planet and possible super-Earth in our Solar System By James Plafke on March 27, 2014 at 10:44 am Comment For the longest time, the Solar System was known to have nine planets. Eventually, Pluto got downgraded to a dwarf planet due to the discovery of various other celestial bodies found in the Solar System that were of similar size. Now, astronomers have discovered another dwarf planet — dubbed 2012 VP113 and just 279.6 miles wide — orbiting the Sun. However, astronomers noticed that something seems out-of-place regarding its orbit, and speculate that the incongruence could originate from a massive body influencing VP113’s orbit — another planet, a super-Earth, that also orbits the Sun.

VP113 orbits the Sun at a distance 80 times that of Earth from the Sun; it never gets closer than 7.4 billion miles (or 12 billion kilometers) from the Sun, and can reach up to 41.6 billion miles (67 billion kilometers) away. The dwarf planet has suffered from radiation damage, which changed the composition of frozen water and carbon dioxide found on the surface, which gives the the celestial body a pink hue. While it’s certainly interesting to discover a new dwarf planet orbiting the Sun — especially one that extends the known boundary of the Solar System — the potential super-Earth that would be effectively messing up VP113’s orbit is the real gem of the discovery. The Sun is in the center. The purple rings represent the orbits of Jupiter, Saturn, Uranus, and Neptune. The blue dots represent Pluto and the Kuiper Belt. Another dwarf planet, called Sedna (discovered in 2003), is represented by the orange. The orbit of VP113 is shown in red.

We don’t yet know if the super-Earth actually exists, but the gravity of a planet about 10 times the size of Earth would explain the irregular orbit of VP113. It might seem strange that we can detect the relatively tiny VP113, but couldn’t detect a planet 10 times the size of Earth, which would make it 280 times the size of the VP113. There are a couple of simple reasons this could be. If it exists, the super-Earth is most likely much, much farther away from Earth than VP113 — to the point where its larger size is negated by its extreme distance. However, astronomers have looked for large planets located in the region in the past, and didn’t find anything. That doesn’t mean that the planets aren’t there, though, as astronomers have generally looked for the hot signatures of gas giants, rather than the signatures of a more solid, cooler planet. Basically, astronomers might have just been looking for the wrong thing.

(Read: Alien spotting: By 2020, we’ll finally have the ability to locate life-harboring, alien planets .) Generally, the area in which VP113 and this possible super-Earth are located has been thought to be relatively boring — too close to have alien stars and too far away to explore anyway — but the discovery of VP113 and its potential orbit-affecting super-Earth would mean that, actually, there’s a good chance some cool stuff is out there, closer than we think. NASA Has Discovered The First Potentially Habitable Earth-sized Planet NASA Has Discovered The First Potentially Habitable Earth-sized Planet {{article.article.images.featured.caption}} Opinions expressed by Forbes Contributors are their own. Full Bio The author is a Forbes contributor. The opinions expressed are those of the writer. Loading ... Loading ... This story appears in the {{article.article.magazine.pretty_date}} issue of {{article.article.magazine.pubName}}. Subscribe In the hunt for exoplanets (planets outside of our solar system), one of the things that astronomers have been desperately searching for is another planet like Earth that's capable of supporting life. It's been a close thing, so far.

Astronomers have found Earth-sized planets in other solar systems. They have found planets in the "habitable zone" (an orbit where temperatures would be potentially conducive to life) of other solar systems. But they haven't found an Earth-sized planet in the habitable zone of another star. Until now. Today, NASA has announced that its Kepler telescope has uncovered a new solar system about 500 light years away, currently dubbed Kepler 186. Circling that star are five planets, and the outermost planet, Kepler-186f, is about the size of Earth and within the star's habitable zone. "The discovery of Kepler-186f is a significant step toward finding worlds like our planet Earth," NASA's Paul Hertz said in a statement. The star Kepler 186 is a "red dwarf" star, about half the size and mass of our own Sun. It's about 500 light years away from Earth, near the constellation Cygnus in the night sky. The planet itself orbits its sun once every 130 days. If life does exist there, it exists in a rather darker place than Earth.

It only gets about one-third of the energy from its star that the Earth gets, and at high noon it's only about as bright as the Earth is at sunset. Which might pose some interesting questions as to whether plant life could have arisen in the same way as Earth. "Being in the habitable zone does not mean we know this planet is habitable. The temperature on the planet is strongly dependent on what kind of atmosphere the planet has," said researcher Thomas Barclay in a press release. "Kepler-186f can be thought of as an Earth-cousin rather than an Earth-twin. It has many properties that resemble Earth." But just because life doesn't exist on Kepler-186f doesn't mean we should lose hope for finding planets where there is life - the discovery itself shows that Earth-sized planets in a habitable zone aren't unique to our own solar system. "Finding a habitable zone planet comparable to Earth in size is a major step forward," said lead researcher Elisa Quintana in a statement. Follow me on Twitter or Facebook . Read my Forbes blog here .

Solar System Like Ours Found Solar System Like Ours Found By Robert Roy Britt | February 14, 2008 02:00pm ET MORE Artist's rendering of a newfound solar system shows a planet resembling Jupiter (middle) and one about the size of Saturn (middle right). Both planets orbit a star that is about half the size of our sun. Credit: Cheongho Han and colleagues at the Korea Astronomy and Space Science Institute The discovery of a Jupiter-like planet and another about the size of Saturn has astronomers suggesting that solar systems like our own may be common. The newfound worlds both appear to be gaseous and are about 80 percent the sizes of Jupiter and Saturn, the astronomers said today. They orbit a star that is about half the size of our sun and is dimmer and much cooler. “This is the first discovery of a multi-planet system that could be analogous to our solar system,” said research team member Alison Crocker, a Dartmouth College graduate now studying at Oxford University. Several similarities The newfound solar system, about 5,000 light-years away, is more compact than our own.

The larger planet's orbit is 2.3 times as far from its host star as the Earth is from the sun. Jupiter is 5.2 times farther from the sun than Earth. But there are several interesting similarities: The ratio between the masses of the two worlds is about 3:1, similar to the Jupiter/Saturn ratio. The smaller planet is about twice as far from its star as the larger one, just as Saturn is roughly twice as far away from the sun as Jupiter. The two worlds orbit their star in 5 and 14 years, similar to the 2:5 orbit ratio of Jupiter and Saturn. The planets were found using a technique called gravitational lensing , in which light from the faraway planets is bent and magnified by the gravity of a foreground object, in this case a another star. The technique has been used to find three other Jupiter-mass planets, each around different stars, in the past. "This is the first time we had a high-enough magnification event where we had significant sensitivity to a second planet — and we found one," said Scott Gaudi, assistant professor of astronomy at Ohio State University.

"You could call it luck, but I think it might just mean that these systems are common throughout our galaxy." The discoveries, by an international team using 11 telescopes around the world, are detailed in the Feb. 15 issue of the journal Science. The initial observations were made by The Optical Gravitational Lensing Experiment (OGLE). Formation theories Even though their star emits only about 5 percent as much light as the sun, the two planets, namded OGLE-2006-BLG-109Lb and OGLE-2006-BLG-109Lc, are thought to be about the same temperatures as Jupiter and Saturn because of their tighter orbits. “The temperatures are important because these dictate the amount of material that is available for planet formation,” Gaudi said. “Most theorists think that the biggest planet in our solar system formed at Jupiter's location because that is the closest to the sun that ice can form. Saturn is the next biggest because it is in the next location further away, where there is less primordial material available to form planets.” Theorists have wondered if gas giants in other solar systems form in the same way as ours did.

"This system seems to answer in the affirmative," Gaudi said. The leading theory is that a rocky protoplanet forms first, then if it gains enough mass, it attracts a shell of gas. Astronomers don't agree , however, whether that explains all the giant planets in our solar system . Another idea is that the giants collapse from a knot of material, much in the way a star forms. Other worlds? It's also plausible that there could be rocky planets around the star in orbits similar to Venus, Earth or Mars. And icy worlds like Neptune might exist in the system's outer reaches, the researchers said. There are now about 250 known planets beyond our solar system and some 25 multiple-planet system. Among those are setups with rocky worlds just a few times the mass of Earth. "While most planetary systems around other stars substantially differ from [our] solar system, a series of recent detections have brought us closer and closer to home," said Martin Dominik, a University of St. Andrews researcher involved in the discoveries. "Sooner rather than later, someone can be expected to discover an Earth-mass planet orbiting a star other than the sun." Video: Planet Hunters Earth - Educational facts and history of the planet Earth.

Earth Earth is the third planet from the Sun and the fifth largest: Planet Profile mass : 5.972e24 kg History of Earth Earth is the only planet whose English name does not derive from Greek/Roman mythology. The name derives from Old English and Germanic. There are, of course, hundreds of other names for the planet in other languages . In Roman Mythology, the goddess of the Earth was Tellus - the fertile soil (Greek: Gaia , terra mater - Mother Earth). It was not until the time of Copernicus (the sixteenth century) that it was understood that the Earth is just another planet. Earth, of course, can be studied without the aid of spacecraft. Nevertheless it was not until the twentieth century that we had maps of the entire planet. Pictures of the planet taken from space are of considerable importance; for example, they are an enormous help in weather prediction and especially in tracking and predicting hurricanes. And they are extraordinarily beautiful.

The Earth is divided into several layers which have distinct chemical and seismic properties (depths in km): 0- 40 Crust 2890-5150 Outer core 5150-6378 Inner core The crust varies considerably in thickness, it is thinner under the oceans, thicker under the continents. The inner core and crust are solid; the outer core and mantle layers are plastic or semi-fluid. The various layers are separated by discontinuities which are evident in seismic data; the best known of these is the Mohorovicic discontinuity between the crust and upper mantle. Most of the mass of the Earth is in the mantle, most of the rest in the core; the part we inhabit is a tiny fraction of the whole (values below x10^24 kilograms): atmosphere = 0.0000051 outer core = 1.835 inner core = 0.09675 The core is probably composed mostly of iron (or nickel/iron) though it is possible that some lighter elements may be present, too.

Temperatures at the center of the core may be as high as 7500 K, hotter than the surface of the Sun . The lower mantle is probably mostly silicon, magnesium and oxygen with some iron, calcium and aluminum. The upper mantle is mostly olivene and pyroxene (iron/magnesium silicates ), calcium and aluminum. We know most of this only from seismic techniques; samples from the upper mantle arrive at the surface as lava from volcanoes but the majority of the Earth is inaccessible. The crust is primarily quartz (silicon dioxide) and other silicates like feldspar. Taken as a whole, the Earth's chemical composition (by mass) is: 34.6% Iron 0.05% Titanium The Earth is the densest major body in the solar system. The other terrestrial planets probably have similar structures and compositions with some differences: the Moon has at most a small core; Mercury has an extra large core (relative to its diameter); the mantles of Mars and the Moon are much thicker; the Moon and Mercury may not have chemically distinct crusts; Earth may be the only one with distinct inner and outer cores.

Note, however, that our knowledge of planetary interiors is mostly theoretical even for the Earth. Unlike the other terrestrial planets, Earth's crust is divided into several separate solid plates which float around independently on top of the hot mantle below. The theory that describes this is known as plate tectonics . It is characterized by two major processes: spreading and subduction. Spreading occurs when two plates move away from each other and new crust is created by upwelling magma from below. Subduction occurs when two plates collide and the edge of one dives beneath the other and ends up being destroyed in the mantle. There is also transverse motion at some plate boundaries (i.e. the San Andreas Fault in California) and collisions between continental plates (i.e. India/Eurasia).

There are (at present) eight major plates: North American Plate - North America, western North Atlantic and Greenland South American Plate - South America and western South Atlantic Antarctic Plate - Antarctica and the "Southern Ocean" Eurasian Plate - eastern North Atlantic, Europe and Asia except for India African Plate - Africa, eastern South Atlantic and western Indian Ocean Indian-Australian Plate - India, Australia, New Zealand and most of Indian Ocean Nazca Plate - eastern Pacific Ocean adjacent to South America Pacific Plate - most of the Pacific Ocean (and the southern coast of California!) There are also twenty or more small plates such as the Arabian, Cocos, and Philippine Plates. Earthquakes are much more common at the plate boundaries. Plotting their locations makes it easy to see the plate boundaries. The Earth's surface is very young . In the relatively short (by astronomical standards) period of 500,000,000 years or so erosion and tectonic processes destroy and recreate most of the Earth's surface and thereby eliminate almost all traces of earlier geologic surface history (such as impact craters). Thus the very early history of the Earth has mostly been erased.

The Earth is 4.5 to 4.6 billion years old, but the oldest known rocks are about 4 billion years old and rocks older than 3 billion years are rare. The oldest fossils of living organisms are less than 3.9 billion years old. There is no record of the critical period when life was first getting started. 71 Percent of the Earth's surface is covered with water. Earth is the only planet on which water can exist in liquid form on the surface (though there may be liquid ethane or methane on Titan's surface and liquid water beneath the surface of Europa ). Liquid water is, of course, essential for life as we know it. The heat capacity of the oceans is also very important in keeping the Earth's temperature relatively stable. Liquid water is also responsible for most of the erosion and weathering of the Earth's continents, a process unique in the solar system today (though it may have occurred on Mars in the past). The Earth's atmosphere is 77% nitrogen, 21% oxygen, with traces of argon, carbon dioxide and water.

There was probably a very much larger amount of carbon dioxide in the Earth's atmosphere when the Earth was first formed, but it has since been almost all incorporated into carbonate rocks and to a lesser extent dissolved into the oceans and consumed by living plants. Plate tectonics and biological processes now maintain a continual flow of carbon dioxide from the atmosphere to these various "sinks" and back again. The tiny amount of carbon dioxide resident in the atmosphere at any time is extremely important to the maintenance of the Earth's surface temperature via the greenhouse effect . The greenhouse effect raises the average surface temperature about 35 degrees C above what it would otherwise be (from a frigid -21 C to a comfortable +14 C); without it the oceans would freeze and life as we know it would be impossible. (Water vapor is also an important greenhouse gas.) The presence of free oxygen is quite remarkable from a chemical point of view. Oxygen is a very reactive gas and under "normal" circumstances would quickly combine with other elements. The oxygen in Earth's atmosphere is produced and maintained by biological processes. Without life there would be no free oxygen. The interaction of the Earth and the Moon slows the Earth's rotation by about 2 milliseconds per century.

Current research indicates that about 900 million years ago there were 481 18-hour days in a year. Earth has a modest magnetic field produced by electric currents in the outer core. The interaction of the solar wind , the Earth's magnetic field and the Earth's upper atmosphere causes the auroras (see the Interplanetary Medium ). Irregularities in these factors cause the magnetic poles to move and even reverse relative to the surface; the geomagnetic north pole is currently located in northern Canada. (The "geomagnetic north pole" is the position on the Earth's surface directly above the south pole of the Earth's field.) The Earth's magnetic field and its interaction with the solar wind also produce the Van Allen radiation belts, a pair of doughnut shaped rings of ionized gas (or plasma) trapped in orbit around the Earth. The outer belt stretches from 19,000 km in altitude to 41,000 km; the inner belt lies between 13,000 km and 7,600 km in altitude. Earth's Satellite Encyclopedia of the Atmospheric Environment Open Issues Our knowledge of the interior of the Earth is derived almost entirely from highly indirect evidence. How can we get more information?

How fast is Earth's core growing? Despite substantial increases in the solar "constant" the average temperature on the surface of the Earth has remained very stable for several billion years. The best theory is that this has been accomplished by varying the amount of carbon dioxide in the atmosphere to regulate the greenhouse effect . But just how is this done? The Gaia Hypothesis asserts that the biosphere actively regulates it. More detailed information about Venus and Mars may provide clues. How much more carbon dioxide can we dump into the Earth's atmosphere before it ends up like Venus? New Planet Found in Our Solar System? New Planet Found in Our Solar System? Odd orbits of remote objects hint at unseen world, new calculations suggest. View Images Artist's conception of a small icy object beyond Pluto (file picture). Illustration courtesy G. Bacon, STScI/NASA An as yet undiscovered planet might be orbiting at the dark fringes of the solar system , according to new research.

Related Content This Week’s Night Sky: Watch Jupiter and Uranus Sparkle Too far out to be easily spotted by telescopes, the potential unseen planet appears to be making its presence felt by disturbing the orbits of so-called Kuiper belt objects, said Rodney Gomes, an astronomer at the National Observatory of Brazil in Rio de Janeiro. Kuiper belt objects are small icy bodies—including some dwarf planets —that lie beyond the orbit of Neptune . Once considered the ninth planet in our system, the dwarf planet Pluto, for example, is one of the largest Kuiper belt objects, at about 1,400 miles (2,300 kilometers) wide. Dozens of the other objects are hundreds of miles across, and more are being discovered every year. (See "Three New 'Plutos'? Possible Dwarf Planets Found." ) What's intriguing, Gomes said, is that, according to his new calculations, about a half dozen Kuiper belt objects—including the remote body known as Sedna—are in strange orbits compared to where they should be, based on existing solar system models.

(Related: "Pluto Neighbor Gets Downsized." ) The objects' unexpected orbits have a few possible explanations, said Gomes, who presented his findings Tuesday at a meeting of the American Astronomical Society in Timberline Lodge, Oregon. "But I think the easiest one is a planetary-mass solar companion"—a planet that orbits very far out from the sun but that's massive enough to be having gravitational effects on Kuiper belt objects. Mystery Planet a Captured Rogue? For the new work, Gomes analyzed the orbits of 92 Kuiper belt objects, then compared his results to computer models of how the bodies should be distributed, with and without an additional planet. If there's no distant world, Gomes concludes, the models don't produce the highly elongated orbits we see for six of the objects. How big exactly the planetary body might be isn't clear, but there are a lot of possibilities, Gomes added. Based on his calculations, Gomes thinks a Neptune-size world, about four times bigger than Earth, orbiting 140 billion miles (225 billion kilometers) away from the sun—about 1,500 times farther than Earth—would do the trick.

But so would a Mars-size object—roughly half Earth's size—in a highly elongated orbit that would occasionally bring the body sweeping to within 5 billion miles (8 billion kilometers) of the sun. Gomes speculates that the mystery object could be a rogue planet that was kicked out of its own star system and later captured by the sun's gravity. (See "'Nomad' Planets More Common Than Thought, May Orbit Black Holes." ) Or the putative planet could have formed closer to our sun, only to be cast outward by gravitational encounters with other planets. However, actually finding such a world would be a challenge. To begin with, the planet might be pretty dim. Also, Gomes's simulations don't give astronomers any clue as to where to point their telescopes—"it can be anywhere," he said. No Smoking Gun Other astronomers are intrigued but say they'll want a lot more proof before they're willing to agree that the solar system—again—has nine planets. (Also see "Record Nine-Planet Star System Discovered?" ) "Obviously, finding another planet in the solar system is a big deal," said Rory Barnes , an astronomer at the University of Washington.

But, he added, "I don't think he really has any evidence that suggests it is out there." Instead, he added, Gomes "has laid out a way to determine how such a planet could sculpt parts of our solar system. So while, yes, the evidence doesn't exist yet, I thought the bigger point was that he showed us that there are ways to find that evidence." Douglas Hamilton , an astronomer from the University of Maryland, agrees that the new findings are far from definitive. "What he showed in his probability arguments is that it's slightly more likely. He doesn't have a smoking gun yet." And Hal Levison , an astronomer at the Southwest Research Institute in Boulder, Colorado, says he isn't sure what to make of Gomes's finding. "It seems surprising to me that a [solar] companion as small as Neptune could have the effect he sees," Levison said. But "I know Rodney, and I'm sure he did the calculations right." Comment on This Story Earth's Name SO JUST WHAT IS THE NAME OF OUR PLANET? We know our world as the Earth. But is that its name? The other planets of our solar system are all named for mythological beings.

Venus is the Roman goddess of love and beauty; Mars, the Roman god of war; Jupiter the king of the Roman gods. But the Earthï¿½what is it named for? Dirt? And what about the moon? It, too, has fallen between the celestial cracks. Other planets' satellites have been endowed with beautiful names from mythology: Miranda, Titan, Ganymede, Charon. But our moon is just, well, "the moon." The problem, when you get right down to it, is that our planet and its natural satellite do not have official names. The explanation for this dates back many centuries. "During antiquity, people knew of five planets," explains E. N. Genovese, Professor Emeritus of Classics and Humanities at San Diego State University. "In the fourth century BCE, they called Jupiter 'Zeus-Star,' Saturn 'Chronos-Star,' Venus 'Aphrodite-Star,' Mercury 'Hermes-Star,' and Mars 'Ares-Star.' ï¿½The moon was given the name 'Selene' in Greek,ï¿½ he continued.

ï¿½It's just a generic name for something that shines, as is the Latin 'Luna.' Neither word has anything to do with divinities, but they were later applied to divinities of those bodies. Then as mythology developedï¿½because there were two namesï¿½people made a separation and lost touch with the original application of the name. "The same goes for 'Earth.' The word is Germanicï¿½the German word for Earth is Erde. It's just a word for the ground or dirt, and it got extended to something larger. Of course, when the word was first derived, people had no sense of the Earth being one of the planets. Once that was established, the name got transferred rather quickly." This worked fine for many centuries. Then, in March of 1781, musical composer and amateur astronomer William Herschel found a new planet among the stars of the constellation Gemini. In an attempt to get Englandï¿½s King George III on his side (and some money in his pocket for doing astronomy), Herschel suggested naming the new world Georgium Sidusï¿½ï¿½Georgeï¿½s Starï¿½ï¿½after the King.

Fortunately, saner minds prevailed, and it was eventually named ï¿½Uranusï¿½ï¿½the Latinized form of ï¿½Ouranosï¿½, the Greek god of the heavens. Strictly speaking, Uranus was the only Greek name among the Roman planetary names. But since Uranus was the god of the heavens, it seemed appropriate for the first planet found in modern times. Later, when large bodies were discovered in 1846 and 1930, scientists named them after the Roman gods Neptune and Pluto. Today, as astronomical discoveries mount at a record pace, astronomers spend large amounts of time devising names. Charged with this task is the Working Group for Planetary System Nomenclatrure (WGPSN) of the International Astronomical Union (IAU). "We try to follow a consistent theme," says Merton Davies of the Rand Corporation, a former member of that group. "For instance, the names of all except one of the original satellites of Uranus were taken from Shakespeare. So when new satellites were discovered at Uranus, we selected names from Shakespeare.

At Neptune we use a theme of water gods." Has the IAU ever considered creating and approving a proper name for our planet and its natural satelliteï¿½something to replace the generic terms Earth and moon? "I suspect not," says Davies. "The main reason is that the names work. They're within the literature, and they're useful in communication. It would be a terrible chore to try to change them." Granted, there are more pressing problems facing us today. But suppose we did want to name the Earth and the moon; what might we come up with? Our first thought might be to call our planet Terra, from which such words as "terrestrial" have sprung. After all, it seems most natural. But it would not fit the scheme; Terra is not the name of a god. More appropriate might be Tellus, the Roman goddess of the earth, protector and developer of the sown seed. We, then, would be named Tellurians. The moon has been known by many names over the ages: Artemis, Diana, Phoebe, Cynthia, and Selene. Perhaps most fitting is Luna, Roman goddess of the moon and the months. Future inhabitants of that world might then be known as Lunarians.

At present, of course, it's all academic. The Earth is the Earth and the moon is the moon. And that suits some people just fine. "To me, the most beautiful words are the simplest and the oldest," says Charles Harrington Elster, author of the book There Is No Cow In Moscow. "They're the most flexible and the most useful. The fixed names of the planets that came from classical mythology are quite lovely. But you'll never change Earth and moon." Beautiful words, yes. Proper names, no. And while it's true that having no official name for our planet and its natural satellite may not seem important now, it may become necessary someday. Imagine the confusion in trying to draw up treaties, diplomatic arrangements, and trade agreements with future human colonists of other worlds without having an official name for ours. And just wait until our first encounter with an extraterrestrial beingï¿½one who has visited worlds throughout our galaxy. I'd love to see the smirk on his little green face when we tell him our planet doesn't have a name. Why should it? It's the Earth! What are the names of the earth, moon, sun, and solar system? (Beginner) - Curious About Astronomy?

Ask an Astronomer The Sun What are the names of the earth, moon, sun, and solar system? (Beginner) All the other planets (Mercury, Venus, Mars, etc.) have names. What's the Earth's name? The other moons in the solar system have names too (Phobos, Io, Titan, etc.). What's our moon's name? Our galaxy has a name: the Milky Way. So what's the name of our solar system? The name of our planet is the Earth. The name of our moon is the Moon. The name of our solar system is the Solar System. Notice that I capitalize them, because when used as names, they are proper nouns. This also helps us distinguish between the planet Earth and earth (meaning soil), between the Earth's Moon and moon (meaning the natural satellite of a planet), and between our Solar System and any other solar systems (since any system containing a star and a planet or a planet-forming disk can be called a solar system.) This is the English language usage approved by the International Astronomical Union , the body in charge of naming celestial objects.

It may seem odd that these important objects don't have names, but if you think about it, it just reinforces their importance. For example, the Moon is the Moon, not just any moon. It requires no other name, because it's the most important moon! You may read or hear people using Luna for the Moon, or Terra or Gaia for the Earth, or Sol for the Sun, but in English-speaking countries, these are poetic terms, often seen in science fiction stories, but not used by astronomers in scientific writing. In some countries where Romance languages are spoken, these terms are the official names. It's also interesting to note that most astronomers do not call our galaxy the Milky Way in technical writing--they call it the Galaxy. This page was last updated June 28, 2015.

Question: Terra is another name for which planet in our solar system?
Answer: Earth