Merkur Symbol Dateiverwendung
Himmelskörper[Bearbeiten | Quelltext bearbeiten]. Planeten. Name, Symbol, Unicode- Zeichen*, Bedeutung. Merkur · Merkur. Deutsch: Astronomisches und astrologisches Symbol für den Planeten Merkur, und Unicode U+F (☿). Español: Símbolo astronómico y astrológico del planeta. CODE-Knacker - Lexikon der Codes-Symbole-Kurzzeichen: Planetensymbole. Merkur. Symbol steht für den geflügelten Helm des römischen Götterboten. Planet, Symbol, Bedeutung, Metall, Tag. Merkur, ☿, Merkurs Flügelhelm und Hermesstab, Quecksilber, Mittwoch. –, –, Drittes Geschlecht. Venus, ♀. Der Planet Merkur repräsentiert den Verstand und die Lernfähigkeit, er ist ein Symbol für Denkvermögen und Kommunikation. Alle Tätigkeiten, die mit diesen.
Merkur-Glyphe astrologische Symbol Halskette Schlüsselanhänger, Astrologie Planet Merkur Symbol - Alchemie Symbole - okkulten esoterischen Schmuck. Schau dir unsere Auswahl an merkur symbol an, um die tollsten einzigartigen oder spezialgefertigten, handgemachten Stücke aus unseren Shops zu finden. Planet, Symbol, Bedeutung, Metall, Tag. Merkur, ☿, Merkurs Flügelhelm und Hermesstab, Quecksilber, Mittwoch. –, –, Drittes Geschlecht. Venus, ♀. Thus species that are high on the food chain amass body burdens of mercury that can be ten times higher than the Arafat Abou Chaker Immobilien they consume. A serious industrial disaster was the dumping of mercury compounds into Minamata Bay, Japan. Bibcode : Sci It reacts with chlorine to give mercuric chloride, which resists further oxidation. Further Merkur Symbol Link planets and Days of the week. Medieval Johannes Kamateros, 12th century form of the Venus symbol; the horizontal stroke was added to form a Christian cross in the early modern period. According to measurements taken by Mariner 10it is about 1. American Astronomical Society Meeting Allen's astrophysical quantities.
You can help. Summary Description Mercury symbol. Nederlands: Astronomisch en astrologisch symbool voor de planeet Mercurius.
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Views Read View on Commons. The Planetary Society. Retrieved June 9, Retrieved April 11, Retrieved August 20, Space Science Reviews.
Bibcode : SSRv July 12, Bibcode : Sci Geological Survey. August 5, Mercury's crust is more analogous to a marbled cake than a layered cake.
Bibcode : mses. Washington Post. Washington, D. Retrieved December 22, Earth, Moon, and Planets. Bibcode : Moon Journal of Geophysical Research.
Bibcode : JGR Lunar and Planetary Science. Proceedings of a workshop held at The Field Museum. September 26, Retrieved September 28, Nature Geoscience.
Bibcode : NatGe August 15, Earth and Planetary Science Letters. September 30, March The New York Times. Archived from the original on November 29, Sean C.
Physics and Chemistry of the Solar System 2nd ed. Academic Press. Physics and Chemistry of the Solar System.
Retrieved June 3, June 2, Retrieved May 23, Bulletin of the American Astronomical Society. Bibcode : DPS Bibcode : SSRv..
University of Arizona Press. Retrieved May 18, University of Michigan. June 30, December 10, The New Solar System. Cambridge University Press.
Astronomy: The Solar System and Beyond 4th ed. Brooks Cole. January 6, Retrieved August 10, January 30, Archived from the original on March 31, Bibcode : Natur.
Retrieved July 18, Archived from the original on July 28, Retrieved April 12, Retrieved May 20, Cosmic Perspectives in Space Physics.
Astrophysics and Space Science Library. Goodsell Observatory of Carleton College. Oliver Hawkins, more or less alumnus and statistical legend, wrote some code for us, which calculated which planet was closest to the Earth on each day for the past 50 years, and then sent the results to David A.
Rothery , professor of planetary geosciences at the Open University. Physics Today. Mercury is the closest planet to all seven other planets video.
Retrieved May 29, Dwornik, D. Gault, and R. Archived from the original on October 24, Retrieved October 22, Bibcode : CeMDA.
Astrophysical Journal. Bibcode : ApJ New York: Plenum Press. Reviews of Modern Physics. Bibcode : RvMP Physical Review. Bibcode : PhRv Reflections on Relativity.
Retrieved May 22, Retrieved March 26, Alexis P. March 16, Scientific Reports. A Field Guide to the Stars and Planets.
The Peterson Field Guide Series. Boston: Houghton Mifflin Co. Department of Physics at Fizik Bolumu in Turkey. Retrieved May 24, Sky and Telescope.
Twelve Year Planetary Ephemeris Directory. Archived from the original on August 17, Fourmilab Switzerland. Archived from the original on May 11, Retrieved May 30, Observer's Handbook Royal Astronomical Society of Canada.
March 17, NASA Multimedia. Retrieved March 18, NBC News. Retrieved March 24, The Astronomical Journal. Bibcode : AJ American Astronomical Society Meeting , Bibcode : AAS Archiv für Orientforschung.
April 25, Retrieved July 14, Ermis is the Greek name of the planet Mercury, which is the closest planet to the Sun.
See also the Greek article about the planet. The Planet Mercury. Translated from French by Moore, Patrick.
Shaldon, Devon: Keith Reid Ltd. Astronomy: A Textbook. The symbol for Mercury represents the Caduceus, a wand with two serpents twined around it, which was carried by the messenger of the gods.
A History of Greek Mathematics. Oxford: Clarendon Press. Journal for the History of Astronomy. Bibcode : JHA Religion in China: universism.
American lectures on the history of religions. Putnam's Sons. Retrieved January 8, The Japanese numbers game: the use and understanding of numbers in modern Japan.
The passing of Korea. Samskrita Bharati. The Cambridge Planetary Handbook. University of Texas Press.
Vistas in Astronomy. Bibcode : VA Razaullah History of oriental astronomy: proceedings of the joint discussion at the 23rd General Assembly of the International Astronomical Union, organised by the Commission 41 History of Astronomy , held in Kyoto, August 25—26, Bibcode : Cent Current Science.
Archived from the original PDF on December 23, Retrieved April 23, Seeing in the Dark: How Amateur Astronomers.
Simon and Schuster. November Publications of the Astronomical Society of the Pacific. Bibcode : PASP Atlas of Mercury.
Astronomical Journal. The Data Book of Astronomy. Flight to Mercury. Columbia University Press. SP Atlas of Mercury. Retrieved June 10, May 5, Archived from the original on July 21, Acta Astronautica.
Bibcode : AcAau.. Retrieved June 18, USA Today. Retrieved March 2, January 14, Archived from the original on May 13, Archived from the original on May 10, Retrieved September 30, UPI, November 15, Retrieved November 16, Allen's astrophysical quantities.
High-School Astronomy. New Scientist : — The BMJ. Retrieved 23 October May Their first biological use is in the Linnaean dissertation Plantae hybridae xxx sistit J.
A coat of arms including a copper sign is recorded for ; the current design dates to the early 20th century, and was given official recognition in It was slightly simplified upon the formation of the modern municipality in registered with the Swedish Patent and Registration Office.
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The difficulty in seeing it notwithstanding, Mercury was known at least by Sumerian times, some 5, years ago. In Classical Greece it was called Apollo when it appeared as a morning star just before sunrise and Hermes , the Greek equivalent of the Roman god Mercury , when it appeared as an evening star just after sunset.
Even in more recent eras, many sky observers passed their entire lifetimes without ever seeing Mercury. It is reputed that Nicolaus Copernicus , whose heliocentric model of the heavens in the 16th century explained why Mercury and Venus always appear in close proximity to the Sun, expressed a deathbed regret that he had never set eyes on the planet Mercury himself.
Until the last part of the 20th century, Mercury was one of the least-understood planets, and even now the shortage of information about it leaves many basic questions unsettled.
Messenger was launched in , flew past the planet twice in and once in , and settled into orbit in It mapped the entire surface of Mercury before crashing into the planet in At first glance the surface of the planet looks similar to the cratered terrain of the Moon , an impression reinforced by the roughly comparable size of the two bodies.
Mercury is far denser, however, having a metallic core that takes up about 61 percent of its volume compared with 4 percent for the Moon and 16 percent for Earth.
Mercury's core has a higher iron content than that of any other major planet in the Solar System, and several theories have been proposed to explain this.
The most widely accepted theory is that Mercury originally had a metal—silicate ratio similar to common chondrite meteorites, thought to be typical of the Solar System's rocky matter, and a mass approximately 2.
Alternatively, Mercury may have formed from the solar nebula before the Sun's energy output had stabilized. A third hypothesis proposes that the solar nebula caused drag on the particles from which Mercury was accreting , which meant that lighter particles were lost from the accreting material and not gathered by Mercury.
MESSENGER , which ended in , found higher-than-expected potassium and sulfur levels on the surface, suggesting that the giant impact hypothesis and vaporization of the crust and mantle did not occur because potassium and sulfur would have been driven off by the extreme heat of these events.
Mercury's surface is similar in appearance to that of the Moon, showing extensive mare -like plains and heavy cratering, indicating that it has been geologically inactive for billions of years.
Because knowledge of Mercury's geology had been based only on the Mariner 10 flyby and terrestrial observations, it is the least understood of the terrestrial planets.
For example, an unusual crater with radiating troughs has been discovered that scientists called "the spider". Albedo features are areas of markedly different reflectivity, as seen by telescopic observation.
Mercury has dorsa also called " wrinkle-ridges " , Moon-like highlands , montes mountains , planitiae plains , rupes escarpments , and valles valleys.
Names for features on Mercury come from a variety of sources. Names coming from people are limited to the deceased. Craters are named for artists, musicians, painters, and authors who have made outstanding or fundamental contributions to their field.
Ridges, or dorsa, are named for scientists who have contributed to the study of Mercury. Depressions or fossae are named for works of architecture.
Montes are named for the word "hot" in a variety of languages. Plains or planitiae are named for Mercury in various languages.
Valleys or valles are named for abandoned cities, towns, or settlements of antiquity. Mercury was heavily bombarded by comets and asteroids during and shortly following its formation 4.
Mercury's surface is more heterogeneous than either Mars 's or the Moon 's, both of which contain significant stretches of similar geology, such as maria and plateaus.
Craters on Mercury range in diameter from small bowl-shaped cavities to multi-ringed impact basins hundreds of kilometers across.
They appear in all states of degradation, from relatively fresh rayed craters to highly degraded crater remnants.
Mercurian craters differ subtly from lunar craters in that the area blanketed by their ejecta is much smaller, a consequence of Mercury's stronger surface gravity.
At the antipode of the Caloris Basin is a large region of unusual, hilly terrain known as the "Weird Terrain". One hypothesis for its origin is that shock waves generated during the Caloris impact traveled around Mercury, converging at the basin's antipode degrees away.
The resulting high stresses fractured the surface. Overall, about 15 impact basins have been identified on the imaged part of Mercury.
There are two geologically distinct plains regions on Mercury. Smooth plains are widespread flat areas that fill depressions of various sizes and bear a strong resemblance to the lunar maria.
Notably, they fill a wide ring surrounding the Caloris Basin. Unlike lunar maria, the smooth plains of Mercury have the same albedo as the older inter-crater plains.
Despite a lack of unequivocally volcanic characteristics, the localisation and rounded, lobate shape of these plains strongly support volcanic origins.
It is not clear whether they are volcanic lavas induced by the impact, or a large sheet of impact melt. One unusual feature of Mercury's surface is the numerous compression folds, or rupes , that crisscross the plains.
As Mercury's interior cooled, it contracted and its surface began to deform, creating wrinkle ridges and lobate scarps associated with thrust faults.
The Lunar Reconnaissance Orbiter discovered that similar small thrust faults exist on the Moon. It is thus a " compound volcano ".
Although the daylight temperature at the surface of Mercury is generally extremely high, observations strongly suggest that ice frozen water exists on Mercury.
Mercury is too small and hot for its gravity to retain any significant atmosphere over long periods of time; it does have a tenuous surface-bounded exosphere  containing hydrogen , helium , oxygen , sodium , calcium , potassium and others at a surface pressure of less than approximately 0.
Hydrogen atoms and helium atoms probably come from the solar wind , diffusing into Mercury's magnetosphere before later escaping back into space.
Radioactive decay of elements within Mercury's crust is another source of helium, as well as sodium and potassium.
Water vapor is present, released by a combination of processes such as: comets striking its surface, sputtering creating water out of hydrogen from the solar wind and oxygen from rock, and sublimation from reservoirs of water ice in the permanently shadowed polar craters.
Sodium, potassium and calcium were discovered in the atmosphere during the —s, and are thought to result primarily from the vaporization of surface rock struck by micrometeorite impacts  including presently from Comet Encke.
This would indicate an interaction between the magnetosphere and the planet's surface. Despite its small size and slow day-long rotation, Mercury has a significant, and apparently global, magnetic field.
According to measurements taken by Mariner 10 , it is about 1. The magnetic-field strength at Mercury's equator is about nT.
It is likely that this magnetic field is generated by a dynamo effect, in a manner similar to the magnetic field of Earth.
Particularly strong tidal effects caused by the planet's high orbital eccentricity would serve to keep the core in the liquid state necessary for this dynamo effect.
Mercury's magnetic field is strong enough to deflect the solar wind around the planet, creating a magnetosphere.
The planet's magnetosphere, though small enough to fit within Earth,  is strong enough to trap solar wind plasma.
This contributes to the space weathering of the planet's surface. Bursts of energetic particles in the planet's magnetotail indicate a dynamic quality to the planet's magnetosphere.
The spacecraft encountered magnetic "tornadoes" — twisted bundles of magnetic fields connecting the planetary magnetic field to interplanetary space — that were up to km wide or a third of the radius of the planet.
These twisted magnetic flux tubes, technically known as flux transfer events , form open windows in the planet's magnetic shield through which the solar wind may enter and directly impact Mercury's surface via magnetic reconnection  This also occurs in Earth's magnetic field.
Mercury has the most eccentric orbit of all the planets; its eccentricity is 0. It takes The diagram illustrates the effects of the eccentricity, showing Mercury's orbit overlaid with a circular orbit having the same semi-major axis.
Mercury's higher velocity when it is near perihelion is clear from the greater distance it covers in each 5-day interval.
In the diagram the varying distance of Mercury to the Sun is represented by the size of the planet, which is inversely proportional to Mercury's distance from the Sun.
This varying distance to the Sun leads to Mercury's surface being flexed by tidal bulges raised by the Sun that are about 17 times stronger than the Moon's on Earth.
Mercury's orbit is inclined by 7 degrees to the plane of Earth's orbit the ecliptic , as shown in the diagram on the right. As a result, transits of Mercury across the face of the Sun can only occur when the planet is crossing the plane of the ecliptic at the time it lies between Earth and the Sun, which is in May or November.
This occurs about every seven years on average. Mercury's axial tilt is almost zero,  with the best measured value as low as 0.
This means that to an observer at Mercury's poles, the center of the Sun never rises more than 2. At certain points on Mercury's surface, an observer would be able to see the Sun peek up a little more than two-thirds of the way over the horizon, then reverse and set before rising again, all within the same Mercurian day.
Thus, to a hypothetical observer on Mercury, the Sun appears to move in a retrograde direction. Four Earth days after perihelion, the Sun's normal apparent motion resumes.
For the same reason, there are two points on Mercury's equator, degrees apart in longitude , at either of which, around perihelion in alternate Mercurian years once a Mercurian day , the Sun passes overhead, then reverses its apparent motion and passes overhead again, then reverses a second time and passes overhead a third time, taking a total of about 16 Earth-days for this entire process.
In the other alternate Mercurian years, the same thing happens at the other of these two points. The amplitude of the retrograde motion is small, so the overall effect is that, for two or three weeks, the Sun is almost stationary overhead, and is at its most brilliant because Mercury is at perihelion, its closest to the Sun.
This prolonged exposure to the Sun at its brightest makes these two points the hottest places on Mercury. Maximum temperature occurs when the Sun is at an angle of about 25 degrees past noon due to diurnal temperature lag , at 0.
These points, which are the ones on the equator where the apparent retrograde motion of the Sun happens when it is crossing the horizon as described in the preceding paragraph, receive much less solar heat than the first ones described above.
Mercury attains inferior conjunction nearest approach to Earth every Earth days on average,  but this interval can range from days to days due to the planet's eccentric orbit.
Mercury can come as near as This large range arises from the planet's high orbital eccentricity. The longitude convention for Mercury puts the zero of longitude at one of the two hottest points on the surface, as described above.
However, when this area was first visited, by Mariner 10 , this zero meridian was in darkness, so it was impossible to select a feature on the surface to define the exact position of the meridian.
Therefore, a small crater further west was chosen, called Hun Kal , which provides the exact reference point for measuring longitude.
A International Astronomical Union resolution suggests that longitudes be measured positively in the westerly direction on Mercury.
For many years it was thought that Mercury was synchronously tidally locked with the Sun, rotating once for each orbit and always keeping the same face directed towards the Sun, in the same way that the same side of the Moon always faces Earth.
Radar observations in proved that the planet has a spin-orbit resonance, rotating three times for every two revolutions around the Sun.
The eccentricity of Mercury's orbit makes this resonance stable—at perihelion, when the solar tide is strongest, the Sun is nearly still in Mercury's sky.
The rare resonant tidal locking is stabilized by the variance of the tidal force along Mercury's eccentric orbit, acting on a permanent dipole component of Mercury's mass distribution.
However, with noticeable eccentricity, like that of Mercury's orbit, the tidal force has a maximum at perihelion and therefore stabilizes resonances, like , enforcing that the planet points its axis of least inertia roughly at the Sun when passing through perihelion.
The original reason astronomers thought it was synchronously locked was that, whenever Mercury was best placed for observation, it was always nearly at the same point in its resonance, hence showing the same face.
This is because, coincidentally, Mercury's rotation period is almost exactly half of its synodic period with respect to Earth.
Due to Mercury's spin-orbit resonance, a solar day the length between two meridian transits of the Sun lasts about Earth days.
Simulations indicate that the orbital eccentricity of Mercury varies chaotically from nearly zero circular to more than 0. In , the French mathematician and astronomer Urbain Le Verrier reported that the slow precession of Mercury's orbit around the Sun could not be completely explained by Newtonian mechanics and perturbations by the known planets.
He suggested, among possible explanations, that another planet or perhaps instead a series of smaller 'corpuscules' might exist in an orbit even closer to the Sun than that of Mercury, to account for this perturbation.
The success of the search for Neptune based on its perturbations of the orbit of Uranus led astronomers to place faith in this possible explanation, and the hypothetical planet was named Vulcan , but no such planet was ever found.
The perihelion precession of Mercury is 5, arcseconds 1. Newtonian mechanics, taking into account all the effects from the other planets, predicts a precession of 5, arcseconds 1.
The effect is small: just Similar, but much smaller, effects exist for other Solar System bodies: 8.
Filling in the values gives a result of 0. This is in close agreement with the accepted value of Mercury's perihelion advance of There may be scientific support, based on studies reported in March , for considering that parts of the planet Mercury may have been habitable , and perhaps that life forms , albeit likely primitive microorganisms , may have existed on the planet.
Mercury can be observed for only a brief period during either morning or evening twilight. Mercury can, like several other planets and the brightest stars, be seen during a total solar eclipse.
Like the Moon and Venus, Mercury exhibits phases as seen from Earth. It is "new" at inferior conjunction and "full" at superior conjunction.
The planet is rendered invisible from Earth on both of these occasions because of its being obscured by the Sun,  except its new phase during a transit.
Mercury is technically brightest as seen from Earth when it is at a full phase. Although Mercury is farthest from Earth when it is full, the greater illuminated area that is visible and the opposition brightness surge more than compensates for the distance.
Nonetheless, the brightest full phase appearance of Mercury is an essentially impossible time for practical observation, because of the extreme proximity of the Sun.
Mercury is best observed at the first and last quarter, although they are phases of lesser brightness. The first and last quarter phases occur at greatest elongation east and west of the Sun, respectively.
At both of these times Mercury's separation from the Sun ranges anywhere from Mercury can be easily seen from the tropics and subtropics more than from higher latitudes.
Viewed from low latitudes and at the right times of year, the ecliptic intersects the horizon at a steep angle. At middle latitudes , Mercury is more often and easily visible from the Southern Hemisphere than from the Northern.
This is because Mercury's maximum western elongation occurs only during early autumn in the Southern Hemisphere, whereas its greatest eastern elongation happens only during late winter in the Southern Hemisphere.
An alternate method for viewing Mercury involves observing the planet during daylight hours when conditions are clear, ideally when it is at its greatest elongation.
Care must be taken to ensure the instrument isn't pointed directly towards the Sun because of the risk for eye damage. This method bypasses the limitation of twilight observing when the ecliptic is located at a low elevation e.
Ground-based telescope observations of Mercury reveal only an illuminated partial disk with limited detail. The Hubble Space Telescope cannot observe Mercury at all, due to safety procedures that prevent its pointing too close to the Sun.
Because the shift of 0. The earliest known recorded observations of Mercury are from the Mul. Apin tablets. These observations were most likely made by an Assyrian astronomer around the 14th century BC.
Apin tablets is transcribed as Udu. Ud "the jumping planet". The Babylonians called the planet Nabu after the messenger to the gods in their mythology.
The ancients knew Mercury by different names depending on whether it was an evening star or a morning star.
By about BC, the ancient Greeks had realized the two stars were one. The Greco - Egyptian  astronomer Ptolemy wrote about the possibility of planetary transits across the face of the Sun in his work Planetary Hypotheses.
He suggested that no transits had been observed either because planets such as Mercury were too small to see, or because the transits were too infrequent.
It was associated with the direction north and the phase of water in the Five Phases system of metaphysics. In India, the Kerala school astronomer Nilakantha Somayaji in the 15th century developed a partially heliocentric planetary model in which Mercury orbits the Sun, which in turn orbits Earth, similar to the Tychonic system later proposed by Tycho Brahe in the late 16th century.
The first telescopic observations of Mercury were made by Galileo in the early 17th century. Although he observed phases when he looked at Venus, his telescope was not powerful enough to see the phases of Mercury.
In , Pierre Gassendi made the first telescopic observations of the transit of a planet across the Sun when he saw a transit of Mercury predicted by Johannes Kepler.
In , Giovanni Zupi used a telescope to discover that the planet had orbital phases similar to Venus and the Moon. The observation demonstrated conclusively that Mercury orbited around the Sun.
A rare event in astronomy is the passage of one planet in front of another occultation , as seen from Earth.
Mercury and Venus occult each other every few centuries, and the event of May 28, is the only one historically observed, having been seen by John Bevis at the Royal Greenwich Observatory.
The difficulties inherent in observing Mercury mean that it has been far less studied than the other planets. The effort to map the surface of Mercury was continued by Eugenios Antoniadi , who published a book in that included both maps and his own observations.
In June , Soviet scientists at the Institute of Radio-engineering and Electronics of the USSR Academy of Sciences , led by Vladimir Kotelnikov , became the first to bounce a radar signal off Mercury and receive it, starting radar observations of the planet.
Pettengill and Rolf B. Dyce, using the meter Arecibo Observatory radio telescope in Puerto Rico , showed conclusively that the planet's rotational period was about 59 days.
If Mercury were tidally locked, its dark face would be extremely cold, but measurements of radio emission revealed that it was much hotter than expected.
Astronomers were reluctant to drop the synchronous rotation theory and proposed alternative mechanisms such as powerful heat-distributing winds to explain the observations.
Italian astronomer Giuseppe Colombo noted that the rotation value was about two-thirds of Mercury's orbital period, and proposed that the planet's orbital and rotational periods were locked into a rather than a resonance.
Instead, the astronomers saw the same features during every second orbit and recorded them, but disregarded those seen in the meantime, when Mercury's other face was toward the Sun, because the orbital geometry meant that these observations were made under poor viewing conditions.
Ground-based optical observations did not shed much further light on Mercury, but radio astronomers using interferometry at microwave wavelengths, a technique that enables removal of the solar radiation, were able to discern physical and chemical characteristics of the subsurface layers to a depth of several meters.
Moreover, recent technological advances have led to improved ground-based observations. In , high-resolution lucky imaging observations were conducted by the Mount Wilson Observatory 1.
They provided the first views that resolved surface features on the parts of Mercury that were not imaged in the Mariner 10 mission.
Reaching Mercury from Earth poses significant technical challenges, because it orbits so much closer to the Sun than Earth. Therefore, the spacecraft must make a large change in velocity delta-v to enter a Hohmann transfer orbit that passes near Mercury, as compared to the delta-v required for other planetary missions.
The potential energy liberated by moving down the Sun's potential well becomes kinetic energy ; requiring another large delta-v change to do anything other than rapidly pass by Mercury.
To land safely or enter a stable orbit the spacecraft would rely entirely on rocket motors. Aerobraking is ruled out because Mercury has a negligible atmosphere.
A trip to Mercury requires more rocket fuel than that required to escape the Solar System completely. As a result, only two space probes have visited it so far.
The second close approach was primarily used for imaging, but at the third approach, extensive magnetic data were obtained.
The data revealed that the planet's magnetic field is much like Earth's, which deflects the solar wind around the planet.
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Merkurs Flügelhelm und Hermesstab ; Quecksilber , Mittwoch. Handspiegel der Venus siehe: Venussymbol ; Kupfer , Freitag. Globus mit Äquator und dem Nullmeridian.
Jupiters Blitz oder Adler ; Zinn , Donnerstag. Saturns Sichel oder Sense ; Blei , Samstag. Neptuns Dreizack.
Pfau Symbol der Juno. Kelch , Weinglas. Regenbogen mit Stern im Inneren .