imtoken钱包下载和使用|mercury

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Mercury - NASA Science

ExploreSearchSubmitNews & EventsMultimediaNASA+Mercury OverviewFactsExplorationStoriesGalleryAll PlanetsMercuryVenusEarthMarsJupiterSaturnUranusNeptunePluto & Dwarf PlanetsOur Solar SystemExplore This SectionMercury OverviewFactsExplorationStoriesGalleryAll PlanetsOur Solar SystemMercuryMercury is the closest planet to the Sun, and the smallest planet in our solar system - only slightly larger than Earth's Moon. All about mercuryRead MoreSmall WorldIt is a little bigger than Earth's Moon.Inside TrackMercury orbits closest to the Sun.Fast TimesA year on Mercury is 88 Earth days.Rough SurfaceMercury is cratered like the Moon.Bring a SpacesuitMercury has a thin exosphere.MoonlessMercury has no moons.RinglessMercury has no rings.No LifeMercury can't support life as we know it.Wear Eye ProtectionSunlight is 11 times brighter on Mercury.Greatest HitThe Caloris Basin is a Texas-sized impact site.Planet Mercury OverviewMercury—the smallest planet in our solar system and nearest to the Sun—is only slightly larger than Earth's Moon. Its surface is covered in tens of thousands of impact craters.From the surface of Mercury, the Sun would appear more than three times as large as it does when viewed from Earth, and the sunlight would be as much as 11 times brighter.Despite its proximity to the Sun, Mercury is not the hottest planet in our solar system— that title belongs to nearby Venus, thanks to its dense atmosphere. But Mercury is the fastest planet, zipping around the Sun every 88 Earth days. Mercury is appropriately named for the swiftest of the ancient Roman gods.

Eyes on the Solar System lets you explore the planets, their moons, asteroids, comets and the spacecraft exploring them from 1950 to 2050. Mercury StoriesExplore All Mercury StoriesFeature1 min readWhat to Expect: A Solar Eclipse GuideArticle5 min readMultiple Spacecraft Tell the Story of One Giant Solar Storm6 min readNASA’s Juno Mission Measures Oxygen Production at EuropaArticle5 min readNight-Shining Cloud Mission Ends; Yields High Science Results for NASAArticle6 days ago2 min readMarch’s Night Sky Notes: Constant Companions: Circumpolar Constellations, Part IIArticle6 days agoMercury13 ImagesGo To GalleryGo To GalleryPop CultureThe smallest planet in our solar system has a big presence in our collective imagination. Scores of science fiction writers have been inspired by Mercury, including Isaac Asimov, C. S. Lewis, Ray Bradbury, Arthur C. Clarke, and H. P. Lovecraft. Television and film writers, too, have found the planet an ideal location for storytelling. In the 2007 film "Sunshine," the Icarus II spacecraft goes into orbit around Mercury to rendezvous with the Icarus I.Learn MoreFor Kids: All About MercuryFacts about Mercury for kids.NASA Photojournal: MercuryImages of Mercury from spacecraft.Keep ExploringDiscover More Topics From NASASunFacts About EarthMarsJupiterReturn to topThe National Aeronautics and Space AdministrationNASA explores the unknown in air and space, innovates for the benefit of humanity, and inspires the world through discovery.About NASA's MissionJoin UsHomeNews & EventsMultimediaNASA+MissionsHumans in SpaceEarth & ClimateThe Solar SystemThe UniverseScienceAeronauticsTechnologyLearning ResourcesAbout NASANASA en EspañolFollow NASAMore NASA Social AccountsNASA NewslettersSitemapFor MediaPrivacy PolicyFOIANo FEAR ActOffice of the IGBudget & Annual ReportsAgency Financial ReportsContact NASAAccessibilityPage Editor:SMD Content EditorsResponsible NASA Official for Science:Dana Bolles

Mercury | Facts, Color, Size, & Symbol | Britannica

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Mercury: Facts - NASA Science

ExploreSearchSubmitNews & EventsMultimediaNASA+…MercuryMercury: FactsMercury OverviewFactsExplorationStoriesGalleryAll PlanetsMercuryVenusEarthMarsJupiterSaturnUranusNeptunePluto & Dwarf PlanetsOur Solar SystemExplore This SectionMercury OverviewFactsExplorationStoriesGalleryAll PlanetsOur Solar SystemMercury FactsThe smallest planet in our solar system and nearest to the Sun, Mercury is only slightly larger than Earth's Moon. From the surface of Mercury, the Sun would appear more than three times as large as it does when viewed from Earth, and the sunlight would be as much as seven times brighter.Quick FactsDay: About 59 Earth days (to complete one rotation on its axis)Solar Day: About 176 Earth days (one full day-night cycle)Year: 88 Earth daysRadius: 1,516 miles | 2,439.7 kilometersPlanet Type: TerrestrialContentsIntroductionNamesakePotential for LifeSize and DistanceOrbit and RotationMoonsRingsFormationStructureSurfaceAtmosphereMagnetosphereIntroductionMercury's surface temperatures are both extremely hot and cold. Because the planet is so close to the Sun, day temperatures can reach highs of 800°F (430°C). Without an atmosphere to retain that heat at night, temperatures can dip as low as -290°F (-180°C).Despite its proximity to the Sun, Mercury is not the hottest planet in our solar system – that title belongs to nearby Venus, thanks to its dense atmosphere. But Mercury is the fastest planet, zipping around the Sun every 88 Earth days.NamesakeMercury is appropriately named for the swiftest of the ancient Roman gods.Potential for LifeMercury's environment is not conducive to life as we know it. The temperatures and solar radiation that characterize this planet are most likely too extreme for organisms to adapt to.Size and DistanceWith a radius of 1,516 miles (2,440 kilometers), Mercury is a little more than 1/3 the width of Earth. If Earth were the size of a nickel, Mercury would be about as big as a blueberry.From an average distance of 36 million miles (58 million kilometers), Mercury is 0.4 astronomical units away from the Sun. One astronomical unit (abbreviated as AU), is the distance from the Sun to Earth. From this distance, it takes sunlight 3.2 minutes to travel from the Sun to Mercury.

A 3D model of Mercury, the innermost planet.NASA Visualization Technology Applications and Development (VTAD)Orbit and RotationMercury's highly eccentric, egg-shaped orbit takes the planet as close as 29 million miles (47 million kilometers) and as far as 43 million miles (70 million kilometers) from the Sun. It speeds around the Sun every 88 days, traveling through space at nearly 29 miles (47 kilometers) per second, faster than any other planet.Mercury spins slowly on its axis and completes one rotation every 59 Earth days. But when Mercury is moving fastest in its elliptical orbit around the Sun (and it is closest to the Sun), each rotation is not accompanied by sunrise and sunset like it is on most other planets. The morning Sun appears to rise briefly, set, and rise again from some parts of the planet's surface. The same thing happens in reverse at sunset for other parts of the surface. One Mercury solar day (one full day-night cycle) equals 176 Earth days – just over two years on Mercury.Mercury's axis of rotation is tilted just 2 degrees with respect to the plane of its orbit around the Sun. That means it spins nearly perfectly upright and so does not experience seasons as many other planets do.MoonsMercury doesn't have moons.RingsMercury doesn't have rings.FormationMercury formed about 4.5 billion years ago when gravity pulled swirling gas and dust together to form this small planet nearest the Sun. Like its fellow terrestrial planets, Mercury has a central core, a rocky mantle, and a solid crust.StructureMercury is the second densest planet, after Earth. It has a large metallic core with a radius of about 1,289 miles (2,074 kilometers), about 85% of the planet's radius. There is evidence that it is partly molten or liquid. Mercury's outer shell, comparable to Earth's outer shell (called the mantle and crust), is only about 400 kilometers (250 miles) thick.SurfaceMercury's surface resembles that of Earth's Moon, scarred by many impact craters resulting from collisions with meteoroids and comets. Craters and features on Mercury are named after famous deceased artists, musicians, or authors, including children's author Dr. Seuss and dance pioneer Alvin Ailey.Very large impact basins, including Caloris (960 miles or 1,550 kilometers in diameter) and Rachmaninoff (190 miles, or 306 kilometers in diameter), were created by asteroid impacts on the planet's surface early in the solar system's history. While there are large areas of smooth terrain, there are also cliffs, some hundreds of miles long and soaring up to a mile high. They rose as the planet's interior cooled and contracted over the billions of years since Mercury formed.Most of Mercury's surface would appear greyish-brown to the human eye. The bright streaks are called "crater rays." They are formed when an asteroid or comet strikes the surface. The tremendous amount of energy that is released in such an impact digs a big hole in the ground, and also crushes a huge amount of rock under the point of impact. Some of this crushed material is thrown far from the crater and then falls to the surface, forming the rays. Fine particles of crushed rock are more reflective than large pieces, so the rays look brighter. The space environment – dust impacts and solar-wind particles – causes the rays to darken with time.Temperatures on Mercury are extreme. During the day, temperatures on the surface can reach 800 degrees Fahrenheit (430 degrees Celsius). Because the planet has no atmosphere to retain that heat, nighttime temperatures on the surface can drop to minus 290 degrees Fahrenheit (minus 180 degrees Celsius).Mercury may have water ice at its north and south poles inside deep craters, but only in regions in permanent shadows. In those shadows, it could be cold enough to preserve water ice despite the high temperatures on sunlit parts of the planet.AtmosphereInstead of an atmosphere, Mercury possesses a thin exosphere made up of atoms blasted off the surface by the solar wind and striking meteoroids. Mercury's exosphere is composed mostly of oxygen, sodium, hydrogen, helium, and potassium.MagnetosphereMercury's magnetic field is offset relative to the planet's equator. Though Mercury's magnetic field at the surface has just 1% the strength of Earth's, it interacts with the magnetic field of the solar wind to sometimes create intense magnetic tornadoes that funnel the fast, hot solar wind plasma down to the surface of the planet. When the ions strike the surface, they knock off neutrally charged atoms and send them on a loop high into the sky.Keep ExploringDiscover More Topics From NASASunPlanetsAsteroids, Comets & MeteorsKuiper BeltReturn to topThe National Aeronautics and Space AdministrationNASA explores the unknown in air and space, innovates for the benefit of humanity, and inspires the world through discovery.About NASA's MissionJoin UsHomeNews & EventsMultimediaNASA+MissionsHumans in SpaceEarth & ClimateThe Solar SystemThe UniverseScienceAeronauticsTechnologyLearning ResourcesAbout NASANASA en EspañolFollow NASAMore NASA Social AccountsNASA NewslettersSitemapFor MediaPrivacy PolicyFOIANo FEAR ActOffice of the IGBudget & Annual ReportsAgency Financial ReportsContact NASAAccessibilityPage Editor:SMD Content EditorsResponsible NASA Official for Science:Dana Bolles

Mercury | Definition, Uses, Density, & Facts | Britannica

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Mercury

Mercury: A complete guide to the closest planet to the sun

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By Charles Q. Choi, Daisy DobrijevicContributions from Scott Dutfield last updated 9 June 2023

Mercury orbits the sun faster than all the other planets in the solar system.

A colorful view of Mercury produced using images from the color base map imaging campaign during MESSENGER's primary mission. These colors are not what Mercury would look like to the human eye, but rather the colors enhance the chemical, mineralogical, and physical differences between the rocks that make up Mercury's surface.

(Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)

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Mercury is the closest planet to the sun and also the smallest planet in the solar system.The small and cratered planet does not have any moons and zips around the sun faster than any other planet in the solar system, hence why the Romans named it after their swift-footed messenger god. It is the second densest planet after Earth, with a huge metallic core roughly 2,200 to 2,400 miles (3,600 to 3,800 kilometers) wide, or about 75% of the planet's diameter. In comparison, Mercury's outer shell is only 300 to 400 miles (500 to 600 km) thick. The combination of its massive core and composition, which includes an abundance of volatile elements, has left scientists puzzled for years.Related: 10 strange Mercury facts The Sumerians also knew of Mercury at least 5,000 years ago. It was often associated with Nabu, the god of writing, according to a site connected to NASA's MESSENGER (Mercury Surface, Space Environment, Geochemistry and Ranging) mission. Mercury was also given separate names for its appearance as both a morning star and an evening star. Greek astronomers knew, however, that the two names referred to the same body, and Heraclitus, around 500 B.C., correctly thought that both Mercury and Venus orbited the sun, not Earth.How hot is Mercury?Because the planet is so close to the sun, Mercury's surface temperature can reach a scorching 840 degrees Fahrenheit (450 degrees Celsius). However, since this world doesn't have much of a real atmosphere to entrap any heat, at night temperatures can plummet to minus 275 degrees Fahrenheit (minus degrees 170 Celsius), a temperature swing of more than 1,100 degrees Fahrenheit (600 degrees Celsius), the greatest in the solar system.How big is Mercury?Mercury is the smallest planet in the solar system — it is only slightly larger than Earth's moon. Since it has no significant atmosphere to stop impacts, the planet is pockmarked with craters. About 4 billion years ago, an asteroid roughly 60 miles (100 km) wide struck Mercury with an impact equal to 1 trillion 1-megaton bombs, creating a vast impact crater roughly 960 miles (1,550 km) wide. Known as the Caloris Basin, this crater could hold the entire state of Texas. Another large impact may have helped create the planet's odd spin, according to research in 2011.Surface of MercuryAs close to the sun as Mercury is, in 2012, NASA's MESSENGER spacecraft discovered water ice in the craters around its north pole, where regions may be permanently shaded from the heat of the sun. The southern pole may also contain icy pockets, but MESSENGER's orbit did not allow scientists to probe the area. Comets or meteorites may have delivered ice there, or water vapor may have outgassed from the planet's interior and frozen out at the poles.Mercury is seen in silhouette as it transits across the face of the sun. (Image credit: NASA/Bill Ingalls)Fast facts:Average distance from the sun: 35,983,095 miles (57,909,175 km). By comparison: 0.38 Earth's distance from the sunPerihelion (closest approach to sun): 28,580,000 miles (46,000,000 km). By comparison: 0.313 times that of EarthAphelion (farthest distance from sun): 43,380,000 miles (69,820,000 km). By comparison: 0.459 times that of EarthDay length: 58.646 Earth daysColor: GrayAs if Mercury isn't small enough, it not only shrank in its past but is continuing to shrink today, according to a 2016 report. The tiny planet is made up of a single continental plate over a cooling iron core. As the core cools, it solidifies, reducing the planet's volume and causing it to shrink. The process crumpled the surface, creating lobe-shaped scarps or cliffs, some hundreds of miles long and soaring up to a mile high, as well as Mercury's "Great Valley," which at about 620 miles long, 250 miles wide and two miles deep (1,000 by 400 by 3.2 km) is larger than Arizona's famous Grand Canyon and deeper than the Great Rift Valley in East Africa. "The young age of the small scarps means that Mercury joins Earth as a tectonically active planet with new faults likely forming today as Mercury's interior continues to cool and the planet contracts," Tom Watters, Smithsonian senior scientist at the National Air and Space Museum in Washington, D.C., said in a NASA statement.Indeed, a 2016 study of cliffs on Mercury's surface suggested the planet may still rumble with earthquakes, or "Mercuryquakes." In addition, in the past, Mercury's surface was constantly reshaped by volcanic activity. However, another 2016 study suggested Mercury's volcano eruptions likely ended about 3.5 billion years ago. One 2016 study suggested that Mercury's surface features can generally be divided into two groups — one consisting of older material that melted at higher pressures at the core-mantle boundary, and the other of newer material that formed closer to Mercury's surface. Another 2016 study found that the dark hue of Mercury's surface is due to carbon. This carbon wasn't deposited by impacting comets, as some researchers suspected — instead, it may be a remnant of the planet's primordial crust.Mercury's magnetic fieldRelated stories:— What is a 'morning star,' and what is an 'evening star'?— Fly by Mercury with this stunning video from the BepiColombo spacecraft— Mercury-bound spacecraft snaps selfie with Venus in close flyby (photo) A completely unexpected discovery made by Mariner 10 was that Mercury possessed a magnetic field. Planets theoretically generate magnetic fields only if they spin quickly and possess a molten core. But Mercury takes 59 days to rotate and is so small — just roughly one-third Earth's size — that its core should have cooled off long ago. "We had figured out how the Earth works, and Mercury is another terrestrial, rocky planet with an iron core, so we thought it would work the same way," Christopher Russell, a professor at the University of California, Los Angeles, said in a University of California, Los Angeles statement.An unusual interior could help to explain the differences in Mercury's magnetic field when compared to Earth. Observations from MESSENGER revealed that the planet's magnetic field is approximately three times stronger in its northern hemisphere than in its southern. Russell co-authored a model that suggests that Mercury's iron core may be turning from liquid to solid at the core's outer boundary rather than the inner."It's like a snow storm in which the snow formed at the top of the cloud and middle of the cloud and the bottom of the cloud too," said Russell. "Our study of Mercury's magnetic field indicates iron is snowing throughout this fluid that is powering Mercury's magnetic field."The discovery in 2007 by Earth-based radar observations that Mercury's core may still be molten could help explain its magnetism, though the solar wind may play a role in dampening the planet's magnetic field.Although Mercury's magnetic field is just 1% the strength of Earth's, it is very active. The magnetic field in the solar wind — the charged particles streaming off the sun — periodically touches upon Mercury's field, creating powerful magnetic tornadoes that channel the fast, hot plasma of the solar wind down to the planet's surface. Does Mercury have an atmosphere?Instead of a substantial atmosphere, Mercury possesses an ultra-thin "exosphere" made up of atoms blasted off its surface by solar radiation, the solar wind and micrometeoroid impacts. These quickly escape into space, forming a tail of particles, according to NASA.The atmosphere of Mercury is a "surface-bound exosphere, essentially a vacuum." It contains 42% oxygen, 29% sodium, 22% hydrogen, 6% helium, 0.5% potassium, with possible trace amounts of argon, carbon dioxide, water, nitrogen, xenon, krypton and neon, according to NASA. Mercury's orbitMercury speeds around the sun every 88 Earth days, traveling through space at nearly 112,000 mph (180,000 km/h), faster than any other planet. Its oval-shaped orbit is highly elliptical, taking Mercury as close as 29 million miles (47 million km) and as far as 43 million miles (70 million km) from the sun. If one could stand on Mercury when it is nearest to the sun, it would appear more than three times as large as it does when viewed from Earth.Mercury is the closest planet to the sun and has a thin atmosphere, no air pressure and an extremely high temperature. Take a look inside the planet. (Image credit: Karl Tate, SPACE.com)Oddly, due to Mercury's highly elliptical orbit and the 59 Earth-days or so it takes to rotate on its axis, when on the scorching surface of the planet, the sun appears to rise briefly, set, and rise again before it travels westward across the sky. At sunset, the sun appears to set, rise again briefly, and then set again.In 2016, a rare transit of Mercury happened, where the planet crossed the face of the sun as seen from Earth. Mercury's transit may have yielded secrets about its thin atmosphere, assisted in the hunt for worlds around other stars, and helped NASA hone some of its instruments.As Mercury takes just Earth days to orbit the sun and Earth takes 365 days, approximately three or four times a year Mercury overtakes Earth during its trip around the sun and an optical illusion occurs, according to The New York Times. Mercury appears to move "backward" across the sky for about three weeks, it is during this time Mercury is said to be in retrograde. Astrologers consider Mercury in retrograde to be a time of misfortune and miscommunication as the perceived backward motion interferes with the planet's rules, according to Dictionary.com. The retrograde motion is explained in this YouTube video from Vox.Mercury Q&A with an expertWe asked Larry Nittler, a cosmochemist who studies the origin and evolution of the solar system at Arizona State University, some questions about Mercury. Larry NittlerSocial Links NavigationCosmochemist Larry Nittler is a cosmochemist at Arizona State University. He studies the origin and evolution of stars, the galaxy, and the solar system, both through laboratory analysis of extraterrestrial materials like meteorites and returned comet and asteroid samples and through planetary remote sensing via spacecraft.What is a fun fact about Mercury?Mercury is in what is called a 3:2 spin-orbit resonance with the sun. This means that it spins on its axis two times for every three times it goes around the sun. So a day on Mercury lasts 59 Earth days, while Mercury's year is 88 Earth days.What temperature is planet Mercury?Minus 292 degrees Fahrenheit (180 degrees Celsius) at night to 986 degrees Fahrenheit (530 degrees Celsius), the maximum during the day.What color is the planet Mercury?Very dark brownish grey.Why isn't Mercury the hottest planet in the solar system?Venus' very thick atmosphere traps so much heat by the greenhouse effect that it has the hottest surface despite being almost twice as far from the sun as Mercury.What are some of the most fascinating aspects of this planet?Although it is the smallest planet in the Solar System (excluding dwarf planets like Pluto), it has a surprisingly large Fe core, which makes it unusually dense and also has led to Mercury having a magnetic field like the Earth's (Venus and Mars do not have such fields).

Although it has a very weak atmosphere (known as an "exosphere"), this is too weak to trap heat so that the day side at 806 degrees Fahrenheit (430 degrees Celsius) is one of the hottest planetary surfaces in the solar system, and the night side one of the coldest at minus 292 degrees Fahrenheit (minus 180 degrees Celsius).How does your work involve Mercury?I was Deputy Principal Investigator on the MESSENGER mission to Mercury, for which I also led the analysis of data from the X-Ray Spectrometer instrument, used to map elemental abundances across the planet. I am currently a Co-I on a similar MIXS instrument onboard the BepiColombo mission which will reach Mercury in 2.5 years.What surprising things about Mercury have we discovered recently?We now know that there are deep impact craters near the poles where sunlight never reaches the bottom, and in many of these, there are large deposits of water ice, and organic matter. These may be the result of comets hitting the planet, and the water and organic molecules hopping across the surface until they find the coldest spots.

We have also learned that although Mercury's magnetic field is like the Earth's in that it is like a large bar magnet, on Mercury, the center of the field is not the center of the planet — it is offset from the equator by a few hundred kilometers. We don't know why.

We have also learned that the surface is rich in relatively volatile elements like sulfur and sodium, despite the planet getting so hot during the day. This helps rule out some ideas about how Mercury formed.What mysteries remain about Mercury?The biggest mystery is how it formed and why it has such a large iron core. There are a few very different ideas to explain this. One is that it formed much bigger than it is, and a giant impact stripped off most of the silicate mantle at some point early in its history. Another is that some process or processes concentrated metal relative to silicate in the inner part of the protoplanetary disk from which the solar system formed so Mercury's building blocks were naturally already enriched in iron. We need both better theoretical modeling of these ideas and more data to eventually work this out.Mercury missions and research The first spacecraft to visit Mercury was Mariner 10, which imaged about 45% of the surface and detected its magnetic field.NASA's MESSENGER orbiter was the second spacecraft to visit Mercury. When it arrived in March 2011, it became the first spacecraft to orbit the planet. The mission came to an abrupt end on April 30, 2015, when the spacecraft, which had run out of fuel, purposely crashed onto the planet's surface for scientists to observe the results.In 2012, scientists discovered a group of meteorites in Morocco that they think could have originated from the planet Mercury. If so, it would make the rocky planet a member of a very select club with samples available on Earth; only the moon, Mars and the large asteroid Vesta have verified rocks in human laboratories. In 2016, scientists released the first-ever global digital-elevation model of Mercury, which combined more than 10,000 images acquired by MESSENGER to take viewers across the wide-open spaces of the tiny world. The model revealed the planet's highest and lowest points — the highest is found just south of Mercury's equator, sitting 2.78 miles (4.48 km) above the average elevation of the planet, while the lowest point resides in Rachmaninoff basin, the suspected home of some of the most recent volcanic activity on the planet, and lies 3.34 miles (5.38 km) below the landscape average.In 2018, a new Mercury explorer was launched. The BepiColombo mission jointly operated by the European and Japanese space agencies is composed of two spacecraft — Mercury Planetary Orbiter and the Mercury Magnetospheric Orbiter — that, after a long trek to Mercury, will split up to better understand the tiny world. The European Space Agency's segment of the mission will focus on studying Mercury's surface while the Japan Aerospace Exploration Agency's portion will focus on the planet's strange magnetosphere.In 2021, BepiColumbo captured its first views of Mercury during a gravity assist flyby. BepiColumbo is scheduled to arrive at Mercury in late 2025, and gather data during its one-year nominal mission with the possibility of a one-year extension, according to ESA. Mercury images Image 1 of 5(Image credit: NASA/JLP)A photomosaic of Mercury's southern hemisphere, made from images captured by NASA's Mariner 10 spacecraft.(Image credit: NASA/Bill Ingalls)Mercury is photographed passing across the sun in the lower third of the image. The planet appears as a small black dot.(Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)An enhanced color composite image of the Caloris Basin on Mercury.(Image credit: NASA/JPL/USGS)Image of Mercury captured by NASA's Mariner 10 spacecraft, the first probe to visit Mercury.(Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)This colorful view of Mercury was produced by using images from the color base map imaging campaign during the primary mission of NASA's MESSENGER spacecraft.Mercury quizAdditional resourcesLearn more about Mercury at NASA's Solar System Exploration website. Read about MESSENGER's top science results via Johns Hopkins Applied Physics Laboratory. See MESSENGER’s crater on Mercury, made when the spacecraft deliberately crashed into the planet BibliographyStrom, Robert G., and Ann L. Sprague. Exploring Mercury: the iron planet. New York: Springer, 2003.Charlier, Bernard, and Olivier Namur. "The origin and differentiation of planet Mercury." Elements: An International Magazine of Mineralogy, Geochemistry, and Petrology 15.1 (2019): 9-14.Mangano, Valeria, et al. "BepiColombo science investigations during cruise and flybys at the Earth, Venus and Mercury." Space Science Reviews 217.1 (2021): 1-81.Hauck, Steven A., and Catherine L. Johnson. "Mercury: Inside the iron planet." Elements: An International Magazine of Mineralogy, Geochemistry, and Petrology 15.1 (2019): 21-26.

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Charles Q. ChoiSocial Links NavigationContributing WriterCharles Q. Choi is a contributing writer for Space.com and Live Science. He covers all things human origins and astronomy as well as physics, animals and general science topics. Charles has a Master of Arts degree from the University of Missouri-Columbia, School of Journalism and a Bachelor of Arts degree from the University of South Florida. Charles has visited every continent on Earth, drinking rancid yak butter tea in Lhasa, snorkeling with sea lions in the Galapagos and even climbing an iceberg in Antarctica. Visit him at http://www.sciwriter.usWith contributions fromScott DutfieldContributor

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Planet Mercury, explained

Skip to contentNewslettersSubscribeMenuNASA's MESSENGER mission captured this colorized image of Caloris Basin on Mercury.

NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of WashingtonSCIENCESTARSTRUCKPlanet Mercury, explainedLearn more about the innermost planet in our solar system.ByVictoria Jaggard7 min readNamed for the fleet-footed Roman messenger god, Mercury is the closest planet to the sun, zipping around our parent star at an average of 36 million miles away. However, Mercury’s orbit is not a perfect circle. The planet can pass as close as 29 million miles and as far away as 43 million miles.Living up to its name, Mercury is the fastest planet in the solar system, speeding along at about 29 miles per second and completing each orbit around the sun in just 88 Earth days. Mercury is also the smallest planet in the solar system, measuring just 3,032 miles wide at its equator. That makes it only slightly larger than Earth’s moon.Because Mercury is so small and so close to the sun, it is the most elusive of the five planets that are visible to the naked eye. You can only catch Mercury at dawn and dusk, and it usually does not rise far above the horizon. But that’s not the only time the tiny planet makes an appearance. Because of its position in the solar system, Mercury passes between Earth and the sun 13 times each century in an event known as a transit. During a transit of Mercury, observers on Earth can see the planet in silhouette as it seems to sweep across the sun’s disk.3:16Since ancient times, people observing the heavens have noticed that the naked-eye planets sometimes appear to move backward, briefly shifting from their usual eastward motion to a westward path across the sky. This retrograde motion is an illusion created when one planet moves faster in its orbit than another, so that it catches up to and passes the slower world. For observers on Earth, Mercury is in retrograde about three to four times a year.If you could watch the skies from the surface of Mercury, you would sometimes catch the rare sight of the sun in retrograde. As Mercury makes its closest approach to our smoldering star, its orbital speed exceeds its rate of rotation on its axis. That means someone standing on Mercury would see the sun start to rise, then briefly set, then rise again all within the same day.Mercurial originsLike the other planets in the solar system, Mercury was born about 4.5 billion years ago, condensing from the swirling ring of dust and gas left over from the sun’s formation. Mercury became what’s known as a terrestrial planet, with a dense metallic core, a rocky mantle, and a solid crust. However, the small planet cooled very quickly, contracting enough within the first billion or so years to prevent magma from escaping through the outer crust and ending geologic activity such as volcanism on the surface.Despite its proximity to our star, Mercury is not the hottest planet in the solar system. With no atmosphere to trap heat, surface temperatures on Mercury can swing from 800 degrees Fahrenheit during the day to -290 degrees Fahrenheit at night. Mercury may even have reservoirs of ice sitting deep inside permanently shadowed craters at its poles. By contrast, the surface of hazy Venus sits at a sweltering 880 degrees Fahrenheit year-round, making it the hottest planet in our solar system.Lack of an atmosphere also means Mercury’s surface is pockmarked by numerous impact craters, since incoming meteors don’t encounter any friction that would cause them to burn up. Seen via telescopes and spacecraft, Mercury looks like a battered world covered in overlapping basins, soaring cliffs, and occasional smooth plains.Bright lines called crater rays also crisscross the surface where impacts crushed the rock and kicked up reflective debris. One of the most notable features on Mercury is Caloris Basin, an impact crater about 960 miles wide that formed early in the planet’s history. Mercury has no rings, no moons, and a relatively weak magnetic field.Mercury is a scarred world covered in craters, ridges, and bright debris from numerous impacts.

Photograph by Carnegie Institution of Washington, Johns Hopkins University Applied Physics Laboratory via NASAMissions to MercuryNASA’s Mariner 10 was the first spacecraft to visit Mercury, conducting a series of three flybys in 1974 and 1975. During this mission, Mariner 10 photographed about 45 percent of the planet’s surface.A NASA mission called MErcury Surface, Space ENvironment, Geochemistry, and Ranging (MESSENGER) became the first probe to orbit Mercury in March 2011. It investigated the planet's composition, the structure of its core, and its magnetic field, in addition to capturing global images of the surface in multiple wavelengths. The mission ended with a planned impact on Mercury's surface in April 2015.In 2018, the European Space Agency is set to launch the BepiColombo mission, which will use two orbiters to further study the innermost planet inside and out.SOURCES · NASA Science: Mercury · NASA Messenger Mission to Mercury · ESA BepiColombo Mission to Mercury · IAU: Categories for Naming Features on Planets and SatellitesRelated: Vintage NASA Photos1 of 20This 1946 image of Earth was the first photograph taken in space.

Photograph by Clyde Holliday, courtesy Bloomsbury AuctionsThis article was updated on October 19, 2018.Related TopicsMERCURYPLANETARY GEOLOGYSPACE EXPLORATIONSOLAR SYSTEMYou May Also LikeSCIENCEIn the hunt for alien life, this planet just became a top suspectSCIENCE4.5 billion years ago, another planet crashed into Earth. We may have found its leftovers.SCIENCEThe moon is even older than we thoughtSCIENCEDid Pluto ever actually stop being a planet? Experts debate.SCIENCEEarth is a geological oddball in our solar system. This is why.Go FurtherAnimalsResort flamingos are being returned to the wildAnimalsResort flamingos are being returned to the wildHow an ‘extinct’ cicada was rediscovered 100 years laterAnimalsHow an ‘extinct’ cicada was rediscovered 100 years laterThe mystery of the Coast Salish woolly dogAnimalsThe mystery of the Coast Salish woolly dogSingle orca seen killing great white shark for first time everAnimalsSingle orca seen killing great white shark for first time everFirst-ever photos show male humpback whales matingAnimalsFirst-ever photos show male humpback whales matingMeet the newest ‘walking’ fishAnimalsMeet the newest ‘walking’ fishEnvironmentHow animals are adapting to the rise of wildfiresEnvironmentHow animals are adapting to the rise of wildfiresFast fashion goes to die in this Chilean desertEnvironmentFast fashion goes to die in this Chilean desertThis is where ‘forever chemicals’ are hiding in your kitchenEnvironmentThis is where ‘forever chemicals’ are hiding in your kitchenYou're not imagining it—winters are getting warmerEnvironmentYou're not imagining it—winters are getting warmerMexico is treating corn from the U.S. as a threat. Here's why.EnvironmentMexico is treating corn from the U.S. as a threat. Here's why.Jeans are bad for the environment—but a new discovery may helpEnvironmentJeans are bad for the environment—but a new discovery may helpHistory & CultureHow Black artists helped make country music what it is todayHistory & CultureRace in AmericaHow Black artists helped make country music what it is todayThese 3 samurai women were heroes of shogun era JapanHistory & CultureThese 3 samurai women were heroes of shogun era JapanLincoln was killed before their eyes—then their own horror beganHistory & CultureLincoln was killed before their eyes—then their own horror beganWas Manhattan really sold to the Dutch for just $24?History & CultureWas Manhattan really sold to the Dutch for just $24?Why Ramadan is the most sacred month in Islamic cultureHistory & CultureWhy Ramadan is the most sacred month in Islamic cultureWhy daylight saving time exists—at least for nowHistory & CultureWhy daylight saving time exists—at least for nowScienceWhat's the source of your headaches? It could be your neck.ScienceMind, Body, WonderWhat's the source of your headaches? It could be your neck.These 4 medicinal herbs may help keep men healthyScienceThese 4 medicinal herbs may help keep men healthyWhy daylight saving time exists—at least for nowHistory & CultureWhy daylight saving time exists—at least for nowAre BPA substitutes really any safer?ScienceMind, Body, WonderAre BPA substitutes really any safer?This is where ‘forever chemicals’ are hiding in your kitchenEnvironmentThis is where ‘forever chemicals’ are hiding in your kitchenWhat is cortisol—and should you actually be worried about it?ScienceWhat is cortisol—and should you actually be worried about it?TravelWhere to eat in the world’s most visited cityTravelWhere to eat in the world’s most visited cityEat your way around the world with these 6 food travel booksTravelEat your way around the world with these 6 food travel books4 remarkable wild stays in U.S. national parksTravel4 remarkable wild stays in U.S. national parksThe best gifts for women who love travel and adventureLifestyleThe best gifts for women who love travel and adventure7 places to see cherry blossoms in EuropeTravel7 places to see cherry blossoms in EuropeTrace Oppenheimer’s footsteps, from New Mexico to the CaribbeanTravelTrace Oppenheimer’s footsteps, from New Mexico to the CaribbeanLegalTerms of UsePrivacy PolicyYour US State Privacy RightsChildren's Online Privacy PolicyInterest-Based AdsAbout Nielsen MeasurementDo Not Sell or Share My Personal InformationOur SitesNat Geo HomeAttend a Live EventBook a TripBuy MapsInspire Your KidsShop Nat GeoVisit the D.C. MuseumWatch TVLearn About Our ImpactSupport Our MissionMastheadPress RoomAdvertise With UsJoin UsSubscribeCustomer ServiceRenew SubscriptionManage Your SubscriptionWork at Nat GeoSign Up for Our NewslettersContribute to Protect the PlanetFollow usNational Geographic InstagramNational Geographic FacebookNational Geographic TwitterNational Geographic YoutubeNational Geographic LinkedinNational Geographic TiktokNational Geographic RedditUnited States (Change)Copyright © 1996-2015 National Geographic SocietyCopyright © 2015-2024 National Geographic Partners, LLC. All rights reserved

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Planet Mercury

By Emily Osterloff

Mercury has the shortest and fastest orbit around the Sun and experiences dramatic temperature changes as it rotates. It is a world of extremes.

Explore facts about our solar system's fastest planet.

Mercury facts

Equator circumference: 15,329km

Radius: 2,440km

Average distance from Sun: 58 million km

Surface temperature: -180°C to 430°C

Day length: 59 Earth days

Year length: 88 Earth days

Average orbital speed: 170,500km/h (47km/s)

Moons: 0

Planet type: terrestrial

How big is Mercury?

Mercury is slightly larger than our Moon - 15,329 kilometres around its equator. Its radius, the distance from the core's centre to the surface, is 2,440 kilometres. Mercury is about 2.6 times smaller than Earth.

How hot is Mercury?

Mercury's sun-facing side is scorched by temperatures of around 430°C, hot enough to melt lead.

Without a substantial atmosphere to distribute heat away from the areas facing the Sun, the planet's slow rotation makes for stark differences in temperature between its dark and light sides. The side facing away cools to an approximate -180°C.

But despite the intense heat the planet faces as it rotates, areas that are permanently shaded, such as some polar craters, may hold deposits of ice.

Intense changes in temperature from day to night make it impossible for life as we know it to flourish on Mercury.

Although it is the closest planet to the Sun, Mercury isn't the hottest in the solar system. Venus's dense atmosphere causes a greenhouse effect, resulting in higher temperatures.

This artificially coloured image of Mercury shows the chemical, mineralogical and physical differences on Mercury's rocky surface © NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington Via Flickr (CC BY 2.0)

How far from the Sun is Mercury?

Mercury's orbit is elongated, taking an almost oval- or egg-shaped course around the Sun. This means that its distance from the Sun varies throughout its circuit, between approximately 46 million and 70 million kilometres.

Mercury speeds around the Sun at nearly 47 kilometres per second - almost 60% faster than Earth's orbiting speed.

How long is a day on Mercury?

Days on Mercury are very long because the planet rotates very slowly. One day-long spin lasts for 59 Earth days. But because of its fast orbit, one Mercury year takes 88 Earth days. This means that two years on Mercury lasts for only three days.

The planet's sunrise would be unusual to us on Earth. Due to its elongated orbit and slow rotation, from some places on Mercury's surface, the Sun appears to rise briefly before setting and rising again. At sunset, the reverse happens, with the Sun appearing to set twice.

The planet spins almost vertically on its axis, so its poles are never fully sunlit. The lack of tilt also means that the planet does not experience yearly seasons like Earth.

This model projects what the northern pole of Mercury may look like. The planet's vertical spin means that the pole is never fully sunlit. © NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington Via Flickr (CC BY 2.0)

What is Mercury's atmosphere made of?

Mercury has little atmosphere, but what it does have is made up mostly of oxygen, sodium, hydrogen, helium and potassium.

The thin atmosphere, or exosphere, does little to prevent or slow down impacts from extraterrestrial objects, leaving the surface littered with craters. In appearance it is similar to Earth's Moon.

The planet is terrestrial, meaning that it has a solid surface and is mainly made of silicate rocks or metals. The planet Mercury is mainly made up of iron.

Mercury has no moons. The planet's close proximity to the Sun makes having moons impossible, as the star's strong gravitational pull would likely pull them out of the planet's orbit.

The cratered surface of Mercury © NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington Via Flickr (CC BY 2.0)

Who discovered Mercury?

Mercury is one of the five classical planets visible with the naked eye and is named after the swift-footed Roman messenger god. It is not known exactly when the planet was first discovered - although it was first observed through telescopes in the seventeenth century by astronomers Galileo Galilei and Thomas Harriot.

Only two spacecraft, both robotic and launched by NASA, have visited Mercury so far, making it the least explored terrestrial planet. Mariner 10 launched in 1973 and imaged around 45% of the planet's surface from 1974 until its end of mission in March 1975.

MESSENGER was launched in 2004 and entered Mercury's orbit in 2011, making it the first spacecraft to do so. This mission lasted for four years before the probe succumbed to the planet's gravity and impacted its surface in 2015. It collected extensive data and images and transmitted them back to Earth to be studied by scientists.

BepiColombo is a joint space mission by the European Space Agency (ESA) and Japan Aerospace Exploration Agency (JAXA), currently proposed to be launched in 2018, with the aim to reach Mercury in December 2025.

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Mercury: Facts about the smallest planet

References

By Patrick Pester published 15 May 2022

Mercury is a planet of extremes.

Mercury in space surrounded by stars. Image elements furnished by NASA.

(Image credit: Shutterstock)

Jump to:

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Temperature

What is Mercury made of?

Mercury retrograde

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Mercury is the closest planet to the sun and the smallest planet in our solar system. With a diameter of about 3,032 miles (4,880 kilometers), Mercury is less than half the size of Earth, which is about 7,926 miles (12,756 km) in diameter. But what Mercury lacks in size, it makes up for in speed: It orbits the sun faster than any other planet in the solar system. How did Mercury get its name?The planet is named after the Roman deity Mercury, the speedy messenger of the gods, who was the Roman equivalent of the Greek god Hermes. Mercury orbits our sun every 88 days — faster than any other planet in the solar system — and a year on Mercury is less than three Earth months. This swift orbit inspired the ancient Romans to associate the small planet with Mercury, according to Cool Cosmos, a website run by the Infrared Processing and Analysis Center at the California Institute of Technology, while the ancient Greeks associated the planet with Hermes, according to the European Southern Observatory.Mercury is visible in the night sky without a telescope and has been known to humans around the world for thousands of years. The Sumerians made one of the earliest known records of the planet in around 3,000 B.C., according to Cool Cosmos. Is Mercury the hottest planet?As Mercury is the closest planet to the sun, you might think it's the hottest planet. However, Mercury lacks an atmosphere like Earth's that can trap and hold heat, so the side facing away from the sun is always very cold — especially as it takes about 59 Earth days for the slow-spinning Mercury to complete a rotation. Temperatures on the surface of Mercury can still reach a toasty 800 degrees Fahrenheit (427 degrees Celsius) on the day side but can fall to as low as minus 290 F (minus 179 C) on the night side, according to NASA. Venus, the second planet from the sun, is the hottest planet because it has a dense atmosphere that retains heat from the sun's rays. Venus has a surface temperature of about 860 degrees Fahrenheit (462 degrees Celsius) and stays that hot on both the day and night sides, Live Science previously reported. Related: The sun has blasted Mercury with a plasma waveWhat is Mercury made of?Mercury is largely composed of iron, according to the Natural History Museum in London, U.K. It has an inner core with a liquid metal outer core and is encased in a mantle and crust, just like Earth. Mercury's inner core is solid and close in size to Earth's, despite Mercury being a much smaller planet overall, a 2019 study published in the journal Geophysical Research Letters found.Instead of a full atmosphere, Mercury has an exosphere — the name given to only the thin outer layer of Earth's atmosphere. Mercury's exosphere is formed by solar wind and meteoroid strikes blasting atoms off its surface, according to NASA. The exosphere gives Mercury llittle protection from objects like asteroids and the planet is pockmarked with craters, so much so that Mercury looks similar to Earth's moon. There are no moons orbiting Mercury because it's so close to the sun that the sun's gravity likely pulls them away, according to the Natural History Museum in London.What is Mercury retrograde?Mercury retrograde is when the planet appears to be, but is not actually, moving backward in the sky. It's an optical illusion caused by humans' perspective of seeing the smaller planet catch up and pass Earth as it curves around the sun, Live Science previously reported. Some astrologists associate Mercury in retrograde with disruptions to daily life on Earth, but there's no scientific evidence for this. "The idea that the gravity from these very distant bodies affects our lives in some way just doesn't work in the framework of physics," Jean-Luc Margot, a professor of astronomy and planetary science at the University of California, Los Angeles, previously told Live Science. The retrograde illusion happens with other planets that Earth passes, and it's not that rare. The Mercury retrograde periods in 2022 are Jan. 13 to Feb. 3, May 10 to June 2, Sep. 9 to Oct. 1, and Dec. 28 to Jan. 18 (2023), according to The Old Farmer’s Almanac. Related: Mercury probe snaps stunning photos of our planet during Earth flyby Mercury transits the sun on Nov. 11, 2019. (Image credit: NASA/SDO/HMI/AIA)Is there life on Mercury?Scientists still have much to learn about Mercury, but they have no reason to think it harbors life. Mercury's searing and freezing temperatures, as well as its abundance of solar radiation, are likely too extreme for any living organisms to handle, according to NASA. Furthermore, thanks to probes like the MESSENGER (Mercury Surface, Space Environment, Geochemistry, and Ranging) spacecraft, about 98% of the surface of Mercury has been photographed in detail, according to the MESSENGER website. MESSENGER confirmed evidence of frozen water on Mercury in 2011. The ice is congregated at the poles in craters so it is shielded from the sun's rays. Much of this ice may have been carried to Mercury on asteroids. However, a 2020 study published in the Astrophysical Journal Letters found that mercury could be creating up to 10% of its own ice.Related stories—The Goldilocks zone: The place in a solar system that's just right—Rare Mercury transit, the last until 2032, thrills skywatchers around the world—5 sci-fi concepts that are possible (in theory) Here's how: Mercury's surface has minerals with groups of bonded oxygen (O) and hydrogen (H) atoms called hydroxyls, which can become energized in the sun's extreme heat and collide to create water (H2O) molecules. While the sun also breaks down these molecules, some drift around the planet and end up in freezing-cold craters at the poles to form ice, Live Science's sister site Space.com previously reported. "It's a little like the song ‘Hotel California.’ The water molecules can check in to the shadows, but they can never leave," study principal investigator Thomas Orlando, a professor at the Georgia Institute of Technology's School of Chemistry and Biochemistry, said in a statement at the time. Additional resourcesTo view an image gallery of Mercury taken by probes, check out NASA's Jet Propulsion Laboratory website. To learn more about the illusion of Mercury retrograde, watch this short YouTube video by Vox. For more information about the MESSENGER probe mission, visit NASA's in-depth MESSENGER page.Originally published on Live Science.

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Patrick PesterSocial Links NavigationLive Science ContributorPatrick Pester is a freelance writer and previously a staff writer at Live Science. His background is in wildlife conservation and he has worked with endangered species around the world. Patrick holds a master's degree in international journalism from Cardiff University in the U.K.

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MERCURY中文(简体)翻译：剑桥词典

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mercury 在英语-中文（简体）词典中的翻译

mercurynoun [ U ] uk

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/ˈmɜː.kjə.ri/ us

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/ˈmɝː.kjə.ri/ (old use quicksilver)

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(symbol Hg) a chemical element that is a heavy, silver-coloured metal, liquid at normal temperatures

汞，水银

Mercury is used in batteries, pesticides, and thermometers.

水银用于电池、杀虫剂与温度计中。

the mercury idiom

old-fashioned informal

the temperature

温度，气温

With the mercury climbing to 40 degrees, beaches and pools will be crowded this afternoon.

随着气温上升到40度，今天下午海滩和游泳池都会人满为患。

Mercurynoun [ S ] uk

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/ˈmɜː.kjə.ri/ us

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/ˈmɝː.kjə.ri/

Mercury noun [S]

(planet)

the planet closest in distance to the Sun

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mercury的例句

mercury

It had a threefold denomination of sulphur, mercury and salt.

来自 Cambridge English Corpus

Many chemists believed that they could obtain running mercury from minerals, particularly from metallic bodies.

来自 Cambridge English Corpus

These solvents would further resolve sulphurs into water, salt, and earth; mercury into salt and phlegm; and salt into phlegmatic water and earth.

来自 Cambridge English Corpus

There are theories not involving infection, including the theory invoking allergy to synthetic detergent, that suggesting antigenicity to mites, and that suggesting allergy to mercury.

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A sodium reagent is used and the chloride ions are reacted with mercury and diphenylcarbazone to form a purple colour.

来自 Cambridge English Corpus

A small volume (about 1 l) of mercury was added in the proximal end of the pipette before use.

来自 Cambridge English Corpus

The mercury pressure sensor, for example is described in less than half a page, while piezoresistive sensors have five pages.

来自 Cambridge English Corpus

Psychometric evidence that mercury from silver dental fillings may be an etiological factor in depression, excessive anger, and anxiety.

来自 Cambridge English Corpus

示例中的观点不代表剑桥词典编辑、剑桥大学出版社和其许可证颁发者的观点。

mercury的翻译

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汞，水銀, 溫度，氣溫, 水星…

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mercurio, Mercurio, mercurio [masculine…

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mercúrio, a temperatura, Mercúrio…

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水銀, 水星, 水銀（すいぎん）…

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civa, Merkür, Venüs'ten önce gelen ve güneşe en yakın gezegen…

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mercure [masculine], mercure, Mercure…

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mercuri, Mercuri…

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kwik, Mercurius…

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زِئبَق, كَوكَب عَطارِد…

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rtuť, Merkur…

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kviksølv, Merkur…

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air raksa, Merkurius…

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ปรอท (สัญลักษณ์ทางเคมีคือ Hg), ดาวพุธ…

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thủy ngân, sao Thủy…

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rtęć, Merkury…

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kvicksilver, merkurius…

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merkuri, Utarid…

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das Quecksilber, der Merkur…

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kvikksølv [neuter], kvikksølv, Merkur…

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수은, 수성…

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ртуть, Меркурій…

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mercurio, Mercurio…

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ртуть, Меркурий…

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mercifully

merciless

mercilessly

mercurial

mercury

mercy

mercy killing

mere

merely

“每日一词”

veggie burger

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/ˈvedʒ.i ˌbɜː.ɡər/

Your browser doesn't support HTML5 audio

/ˈvedʒ.i ˌbɝː.ɡɚ/

a type of food similar to a hamburger but made without meat, by pressing together small pieces of vegetables, seeds, etc. into a flat, round shape

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imtoken钱包下载和使用|mercury

imtoken钱包下载和使用|mercury

水星网络官方网站

Mercury - NASA Science

Mercury | Facts, Color, Size, & Symbol | Britannica

Mercury: Facts - NASA Science

Mercury | Definition, Uses, Density, & Facts | Britannica

Mercury — A complete guide to the closest planet to the sun | Space

Planet Mercury, explained

Planet Mercury | Natural History Museum

Mercury: Facts about the smallest planet | Live Science

MERCURY中文(简体)翻译：剑桥词典

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