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# mercury planetary data

[e] This angle is the maximum altitude at which Mercury is visible in a completely dark sky. With a radius of about 2,440 km (1,516 miles), Mercury is the smallest major planet, smaller even than Jupiter’s largest moon, Ganymede, or Saturn’s largest moon, … {\displaystyle \epsilon =24\pi ^{3}{\frac {a^{2}}{T^{2}c^{2}(1-e^{2})}}} Introduction . 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. Telescopic observers, limited to viewing Mercury periodically under conditions dictated by Mercuryâs angular distance from the Sun, had been misled into concluding that their seeing the same barely distinguishable features on Mercuryâs surface on each viewing occasion indicated a synchronous rotation. [95] Conversely, there are two other points on the equator, 90 degrees of longitude apart from the first ones, where the Sun passes overhead only when the planet is at aphelion in alternate years, when the apparent motion of the Sun in Mercury's sky is relatively rapid. mean distance from Sun: 57,909,227 km (0.39 AU) eccentricity of orbit: 0.2056: inclination of orbit to ecliptic: 7.0° Mercurian year (sidereal period of revolution) 87.97 Earth days: maximum visual magnitude −1.9 [87], Mercury has the most eccentric orbit of all the planets; its eccentricity is 0.21 with its distance from the Sun ranging from 46,000,000 to 70,000,000 km (29,000,000 to 43,000,000 mi). Mercury presumably had spun faster when it was forming, but it was slowed by tidal forces. MESSENGER data used for DE430 and DE431 are from the first year in orbit about Mercury. Gear motors are our highlight. [148] (Note that most such medieval reports of transits were later taken as observations of sunspots. The chances of trapping the spin at the 58.6-day period were greatly enhanced by tidal friction between the solid mantle and molten core of the young planet. Each planet (Mercury, Venus and Mars) has a different orbital period around the sun than Earth does and as a result, interesting patterns emerges. Solar System → Local Interstellar Cloud → Local Bubble → Gould Belt → Orion Arm → Milky Way → Milky Way subgroup → Local Group → Local Sheet → Virgo Supercluster → Laniakea Supercluster → Observable universe → UniverseEach arrow (→) may be read as "within" or "part of". It is the closest planet to the sun . The first spacecraft to visit Mercury, Mariner 10, was in orbit around the Sun when it made three brief flybys of the planet in 1974â75. Planetary Names: Mercury Home . Mercury is one of the eight planets that orbit, or travel around, the sun in the solar system. e Viewed from low latitudes and at the right times of year, the ecliptic intersects the horizon at a steep angle. [169] A proposed alternative approach would use a solar sail to attain a Mercury-synchronous orbit around the Sun. Learn about the length of both a year and a day on Mercury. [112], The perihelion precession of Mercury is 5,600 arcseconds (1.5556°) per century relative to Earth, or 574.10±0.65 arcseconds per century[113] relative to the inertial ICRF. 2013; Dumberry and Rivoldini 2015) indicate core radii of 2000–2060 km and a core proportionately 58–70% of the planetary mass (M , 3.302 ×10 23 kg (Rivoldini et al. [90], Mercury's axial tilt is almost zero,[91] with the best measured value as low as 0.027 degrees. The data set also includes all documentation and supporting materials needed to understand and use the data products. Because its orbit could no longer be accurately controlled, mission controllers instructed the probe to shut down. How Names are Approved . the semi-major axis, and 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. Friedrich Bessel used Schröter's drawings to erroneously estimate the rotation period as 24 hours and an axial tilt of 70°. [70], The icy regions are estimated to contain about 1014–1015 kg of ice,[71] and may be covered by a layer of regolith that inhibits sublimation. [81], On November 29, 2012, NASA confirmed that images from MESSENGER had detected that craters at the north pole contained water ice. The two locations on Mercuryâs equator where this oscillation takes place at noon are called hot poles. Some four and a half decades after NASA’s Mariner 10 spacecraft sped by Mercury, a group of planetary scientists is now talking about landing on … Ground-based telescope observations of Mercury reveal only an illuminated partial disk with limited detail. At both of these times Mercury's separation from the Sun ranges anywhere from 17.9° at perihelion to 27.8° at aphelion. It takes about 116 days for successive elongationsâi.e., for Mercury to return to the same point relative to the Sunâin the morning or evening sky. The data revealed that the planet's magnetic field is much like Earth's, which deflects the solar wind around the planet. Its radio science experiment will also perform a test of Einstein’s theory of relativity. 'It's Not Completely Nuts' - A new explanation for the rocky world's jumbled landscape opens a possibility that it could have had ingredients for habitability", "The Chaotic Terrains of Mercury Reveal a History of Planetary Volatile Retention and Loss in the Innermost Solar System", "NASA Reference Publication 1349; Venus: Twelve year planetary ephemeris, 1995–2006", "NASA spacecraft now circling Mercury – a first", "MESSENGER: Mercury and Ancient Cultures", "Modification of the Earlier Indian Planetary Theory by the Kerala Astronomers (c. 1500 AD) and the Implied Heliocentric Picture of Planetary Motion", "Mercury Passes in Front of the Sun, as Seen From Mars", "MESSENGER to test theory of shrinking Mercury", "MESSENGER Engine Burn Puts Spacecraft on Track for Venus", "Countdown to MESSENGER's Closest Approach with Mercury", "MESSENGER Gains Critical Gravity Assist for Mercury Orbital Observations", "NASA extends spacecraft's Mercury mission", "NASA Mercury Probe Trying to Survive for Another Month", "NASA's Messenger Mission Is Set to Crash Into Mercury", "Messenger's Collision Course With Mercury", "ESA gives go-ahead to build BepiColombo", https://en.wikipedia.org/w/index.php?title=Mercury_(planet)&oldid=995252510, Astronomical objects known since antiquity, CS1 maint: DOI inactive as of November 2020, Articles containing Ancient Greek (to 1453)-language text, Wikipedia indefinitely semi-protected pages, Wikipedia indefinitely move-protected pages, Short description is different from Wikidata, Pages using multiple image with auto scaled images, Articles containing Chinese-language text, Pages using Sister project links with wikidata mismatch, Pages using Sister project links with default search, Wikipedia articles with WORLDCATID identifiers, Creative Commons Attribution-ShareAlike License, This page was last edited on 20 December 2020, at 00:55. The planet is rendered invisible from Earth on both of these occasions because of its being obscured by the Sun,[119] except its new phase during a transit. As the overhead Sun lingers there, heating them preferentially, surface temperatures can exceed 700 kelvins (K; 800 Â°F, 430 Â°C). Distance from Sun (millions of km) Approx. The first of two spacecraft to visit the planet was Mariner 10, which mapped about 45% of its surface from 1974 to 1975. 6 Smallest and innermost planet from the Sun in the Solar System, The so-called "Weird Terrain" formed at the point, Animation of Mercury's and Earth's revolution around the Sun, Size comparison with other Solar System objects. In addition, the extreme heat, not only from the Sun but also reradiated from Mercury itself, challenged spacecraft designers to keep instruments cool enough to operate. Images and GIS Data. [156][157][158] Three years later, radar observations by Americans Gordon H. Pettengill and Rolf B. Dyce, using the 300-meter Arecibo radio telescope in Puerto Rico, showed conclusively that the planet's rotational period was about 59 days. How do planetary scientists analyze and interpret data from laboratory, telescopic, and spacecraft observations of planetary surfaces? e By comparing reflected radar signals with the specific predictions of the general theory, scientists achieved a second important confirmation of relativity. 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. [170], The first spacecraft to visit Mercury was NASA's Mariner 10 (1974–1975). Mercury can come as near as 82.2 gigametres (0.549 astronomical units; 51.1 million miles) to Earth, and that is slowly declining: The next approach to within 82.1 Gm (51.0 million miles) is in 2679, and to within 82.0 Gm (51.0 million miles) in 4487, but it will not be closer to Earth than 80 Gm (50 million miles) until 28,622. The planet's magnetosphere, though small enough to fit within Earth,[81] is strong enough to trap solar wind plasma. MESSENGER’s voyage to Mercury surpassed expectations and ended with its descent and impact onto the surface on April 30, 2015. "MUL" is a cuneiform sign that was used in the Sumerian language to designate a star or planet, but it is not considered part of the actual name. The probe successfully entered an elliptical orbit around the planet on March 18, 2011. 2 [109][110], In 1859, 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. [121] The opposite is true for Venus, which appears brightest when it is a crescent, because it is much closer to Earth than when gibbous. Earth – The only planet in our solar system with liquid water on the surface. This large range arises from the planet's high orbital eccentricity. Therefore, a small crater further west was chosen, called Hun Kal, which provides the exact reference point for measuring longitude. In 1800, Johann Schröter made observations of surface features, claiming to have observed 20-kilometre-high (12 mi) mountains. The Planetary Data System is pleased to announce Release 12 of data collected by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission, including raw and calibrated products acquired 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. Mercury is 5.427 grams per cubic centimeter. History & References . Mass 3/s–2 This made close observation of both sides of the planet impossible,[173] and resulted in the mapping of less than 45% of the planet's surface. Golden, Leslie M., A Microwave Interferometric Study of the Subsurface of the Planet Mercury (1977). Mercuryâs orbital motion has played an important role in the development and testing of theories of the nature of gravity because it is perturbed by the gravitational pull of the Sun and the other planets. 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. of heavy ions of planetary origin. Mercury Venus Earth Mars Jupiter; Mean distance from Sun (millions of kilometers) 57.9 : 108.2 : 149.6 : 227.9 : 778.3: Mean distance from Sun (millions of miles) 36.0 : 67.24 : 92.9 : 141.71 : 483.88: Period of revolution : 88 days : 224.7 days : 365.2 days : 687 days : 11.86 yrs: Rotation period : 59 days : 243 days retrograde : 23 hr 56 min 4 sec : 24 hr 37 min : 9 hr 55 min 30 sec Try to win a Planetary Society Venn Diagram tee and a signed copy of Emily Lakdawalla’s book, The Design and Engineering of Curiosity, by answering this question: What was the first human-made object to hit another world besides Earth? If you’re born with Mercury in sensual Taurus , you may be quite tactile, relying on the power of touch to synthesize data. 2009)). [162] Data from Mariner 10 subsequently confirmed this view. [24] Essentially because Mercury is closest to the Sun, when taking an average over time, Mercury is the closest planet to the Earth,[97] and - in that measure - it is the closest planet to each of the other planets in the Solar System. In developing subsequent missions to Mercury, such as the U.S. Messenger spacecraft launched in 2004, spaceflight engineers calculated complex routes, making use of gravity assists (see spaceflight: Planetary flights) from repeated flybys of Venus and Mercury over the course of several years. 2009; Rivoldini and Van Hoolst 2013; Hauck II et al. [184] MESSENGER's final maneuver was on April 24, 2015, and it crashed into Mercury's surface on April 30, 2015. Four Earth days after perihelion, the Sun's normal apparent motion resumes. Mercury is an extreme planet in several respects. Mercury is technically brightest as seen from Earth when it is at a full phase. [67], 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 one of four inner planets in the Solar System, and has a rocky body like the Earth.It is the smallest planet in the Solar System, with a radius of 2,439.7 km (1,516.0 mi). For many years after the Mariner 10 encounters, the origin of Mercury's magnetic field remained the subject of several competing theories. This would indicate an interaction between the magnetosphere and the planet's surface. [117][118], Mercury's apparent magnitude is calculated to vary between −2.48 (brighter than Sirius) around superior conjunction and +7.25 (below the limit of naked-eye visibility) around inferior conjunction. [96] Its period of retrograde motion as seen from Earth can vary from 8 to 15 days on either side of inferior conjunction. This small motion, about 9.5â² (0.16Â°) of arc per century, has been known for two centuries, and, in fact, all but about 7 percent of itâcorresponding to 43â³ (0.012Â°) of arcâcould be explained by the theory of gravity proposed by Isaac Newton. is the orbital eccentricity, Solar System Scale & Size Planets + Characteristics - Data - Mercury - Venus - Earth - Mars - Jupiter - Saturn - Uranus - Neptune Dwarf Planets Small Solar System … [71] The origin of the ice on Mercury is not yet known, but the two most likely sources are from outgassing of water from the planet's interior or deposition by impacts of comets. It’s a little bigger than Earth’s Moon. This zippy little planet hangs out in a zodiac sign for an average of three weeks. This contributes to the space weathering of the planet's surface. planets (planetary systems for planets with natural satellites) were taken from published val-ues derived from spacecraft tracking data. 2 E056: Planetary Astronomy–Understanding the Origin of the Solar System planetary missions is another way to greatly increase Canadian planetary science return at orders of magnitude lower cost than a Canadian-led mission. However, this does not mean that the two planets are closest over time. The resonance makes a single solar day on Mercury last exactly two Mercury years, or about 176 Earth days. According to measurements taken by Mariner 10, it is about 1.1% the strength of Earth's. However, using this time-average definition of 'closeness' - as noted above - it turns out that Mercury is the closest planet to. Mercury Data. [76][77], Sodium, potassium and calcium were discovered in the atmosphere during the 1980–1990s, and are thought to result primarily from the vaporization of surface rock struck by micrometeorite impacts[78] including presently from Comet Encke. [132] They knew the planet as Στίλβων Stilbōn, meaning "twinkling", and Ἑρμής Hermēs, for its fleeting motion,[133] a name that is retained in modern Greek (Ερμής Ermis). [153], 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. The diagram illustrates the effects of the eccentricity, showing Mercury's orbit overlaid with a circular orbit having the same semi-major axis. The cruise to Mercury lasts 7 years and consists of a mixture of planetary flybys, electric propulsion arcs, and coast arcs. [166] Most of the planet has been mapped by the Arecibo radar telescope, with 5 km (3.1 mi) resolution, including polar deposits in shadowed craters of what may be water ice.[167]. Planets - Data Table Dwarf Planets are listed in a separate table below. The verbs "rotate" and "revolve" mean doing rotation and revolution, respectively. [24][106] [132] The spacecraft used the gravity of Venus to adjust its orbital velocity so that it could approach Mercury, making it both the first spacecraft to use this gravitational "slingshot" effect and the first NASA mission to visit multiple planets. its orbit appears vertical) and is at maximum elongation from the Sun (28°) and also when the Sun is 18° below the horizon, so the sky is just completely dark. [108], Numerical simulations show that a future secular orbital resonant perihelion interaction with Jupiter may cause the eccentricity of Mercury's orbit to increase to the point where there is a 1% chance that the planet will collide with Venus within the next five billion years. a Therefore, the spacecraft must make a large change in velocity (delta-v) to get to Mercury and then enter orbit, as compared to the delta-v required for other planetary missions. [24] Measurements of changes in the probe's orbital velocity were expected to be used to infer details of the planet's interior structure. 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. The Planetary Manifestation Activator™ MERCURY is here to activate the energy of thought and perception, communication, technology and travel. In the other alternate Mercurian years, the same thing happens at the other of these two points. Planet Facts Interesting Planet Facts Mercury – The smallest and fastest planet, it zips around the Sun in only 88 Earth days. Filling in the values gives a result of 0.1035 arcseconds per revolution or 0.4297 arcseconds per Earth year, i.e., 42.97 arcseconds per century. The way we organize, synthesize and transfer data also falls to Mercury, which governs our mobile devices, scheduling and transportation. [188], The European Space Agency and the Japanese Space Agency developed and launched a joint mission called BepiColombo, which will orbit Mercury with two probes: one to map the planet and the other to study its magnetosphere. Observed for only a brief period during either morning or evening twilight Â°C! Also perform a test of Einstein ’ s actually not the hottest mercury planetary data confirmed this.! Found easily, even when using telescopes with 8 cm ( 3.1 in apertures... 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