| 词条 | 3 Juno | ||||||||||||||||||||||||||
| 释义 |
| minorplanet=yes | bgcolour=#D6D6D6 | name= 3 Juno | symbol= | image= Juno orbit 2018.png | image_size= 280 | caption=The orbit of Juno is significantly elliptical with a small inclination, moving between Mars and Jupiter. | discoverer=Karl Ludwig Harding | discovered=September 1, 1804 | mpc_name=(3) Juno | alt_names=none | pronounced ={{IPAc-en|ˈ|dʒ|uː|n|oʊ}} | adjectives=Junonian {{IPAc-en|dʒ|uː|ˈ|n|oʊ|n|i|ə|n}}[1] | named_after = Juno ({{lang-la|Iūno}}) | mp_category=Main belt (Juno clump) | orbit_ref = | epoch=JD 2457000.5 (9 December 2014) | semimajor=2.67070 AU | perihelion=1.98847 AU | aphelion=3.35293 AU | eccentricity=0.25545 | period=4.36463 yr | inclination=12.9817° | asc_node=169.8712° | arg_peri=248.4100° | mean_anomaly={{val|33.077|ul=°}} | avg_speed=17.93 km/s | p_orbit_ref = [2] | p_semimajor = 2.6693661 | p_eccentricity = 0.2335060 | p_inclination = 13.2515192° | p_mean_motion = 82.528181 | perihelion_rate = 43.635655 | node_rate = −61.222138 | dimensions=(320×267×200)±6 km[4] | mean_diameter = 233 km | mean_radius = 135.7±11 [3] | surface_area= 216 000 km2[4] | volume= 8 950 000 km3[4] | mass=2.67 {{e|19}} kg[5] | density={{val|3.20|0.56|ul=g/cm3}}[5] | surface_grav=0.12 m/s2 | escape_velocity=0.18 km/s | rotation=7.21 hr (0.3004 d)[6] | spectral_type=S[7] | rot_velocity= 31.75 m/s[4] | magnitude = 7.4[8][9] to 11.55 |abs_magnitude=5.33[10] | albedo=0.238[10] | angular_size = 0.30" to 0.07" | single_temperature=~163 K max: 301 K (+28°C)[11] }}Juno (minor-planet designation: 3 Juno) is an asteroid in the asteroid belt. Juno was the third asteroid discovered, in 1804, by German astronomer Karl Harding. It is the 11th-largest asteroid, and one of the two largest stony (S-type) asteroids, along with 15 Eunomia. It is estimated to contain 1% of the total mass of the asteroid belt.[12] HistoryDiscoveryJuno was discovered on 1 September 1804, by Karl Ludwig Harding. It was the third asteroid found, but was initially considered to be a planet; it was reclassified as an asteroid and minor planet during the 1850s.[13] NameJuno is named after the mythological Juno, the highest Roman goddess. The adjectival form is Junonian (jūnōnius). With two exceptions, 'Juno' is the international name, subject to local variation: Italian Giunone, French Junon, Russian Yunona, etc.{{#tag:ref|The exceptions are Greek, where the name was translated to its Hellenic equivalent, Hera (3 Ήρα), as in the cases of 1 Ceres and 4 Vesta; and Chinese, where it is called the 'marriage-god(dess) star' (婚神星 hūnshénxīng). This contrasts with the goddess Juno, for which Chinese uses the transliterated Latin name (朱諾 zhūnuò).|group=lower-alpha}} Its planetary symbol is ③. An older symbol, still occasionally seen, is ⚵ (). CharacteristicsJuno is one of the larger asteroids, perhaps tenth by size and containing approximately 1% the mass of the entire asteroid belt.[14] It is the second-most-massive S-type asteroid after 15 Eunomia.[5] Even so, Juno has only 3% the mass of Ceres.[5] The orbital period of Juno is 4.36578 years.[15] Amongst S-type asteroids, Juno is unusually reflective, which may be indicative of distinct surface properties. This high albedo explains its relatively high apparent magnitude for a small object not near the inner edge of the asteroid belt. Juno can reach +7.5 at a favourable opposition, which is brighter than Neptune or Titan, and is the reason for it being discovered before the larger asteroids Hygiea, Europa, Davida, and Interamnia. At most oppositions, however, Juno only reaches a magnitude of around +8.7[16]—only just visible with binoculars—and at smaller elongations a {{convert|3|in|mm|adj=on}} telescope will be required to resolve it.[17] It is the main body in the Juno family.
Juno was originally considered a planet, along with 1 Ceres, 2 Pallas, and 4 Vesta.[32] In 1811, Schröter estimated Juno to be as large as 2290 km in diameter.[18] All four were reclassified as asteroids as additional asteroids were discovered. Juno's small size and irregular shape preclude it from being designated a dwarf planet. Juno orbits at a slightly closer mean distance to the Sun than Ceres or Pallas. Its orbit is moderately inclined at around 12° to the ecliptic, but has an extreme eccentricity, greater than that of Pluto. This high eccentricity brings Juno closer to the Sun at perihelion than Vesta and further out at aphelion than Ceres. Juno had the most eccentric orbit of any known body until 33 Polyhymnia was discovered in 1854, and of asteroids over 200 km in diameter only 324 Bamberga has a more eccentric orbit.[19] Juno rotates in a prograde direction with an axial tilt of approximately 50°.[20] The maximum temperature on the surface, directly facing the Sun, was measured at about 293 K on October 2, 2001. Taking into account the heliocentric distance at the time, this gives an estimated maximum temperature of 301 K (+28 °C) at perihelion.[11] Spectroscopic studies of the Junonian surface permit the conclusion that Juno could be the progenitor of chondrites, a common type of stony meteorite composed of iron-bearing silicates such as olivine and pyroxene.[21] Infrared images reveal that Juno possesses an approximately 100 km-wide crater or ejecta feature, the result of a geologically young impact.[22][23] Based on MIDAS infrared data using the Hale telescope, an average radius of 135.7±11 was reported in 2004.[24] ObservationsJuno was the first asteroid for which an occultation was observed. It passed in front of a dim star (SAO 112328) on February 19, 1958. Since then, several occultations by Juno have been observed, the most fruitful being the occultation of SAO 115946 on December 11, 1979, which was registered by 18 observers.[25] Juno occulted the magnitude 11.3 star PPMX 9823370 on July 29, 2013,[26] and 2UCAC 30446947 on July 30, 2013.[27] Radio signals from spacecraft in orbit around Mars and on its surface have been used to estimate the mass of Juno from the tiny perturbations induced by it onto the motion of Mars.[28] Juno's orbit appears to have changed slightly around 1839, very likely due to perturbations from a passing asteroid, whose identity has not been determined.[29] In 1996, Juno was imaged by the Hooker Telescope at Mount Wilson Observatory at visible and near-IR wavelengths, using adaptive optics. The images spanned a whole rotation period and revealed an irregular shape and a dark albedo feature, interpreted as a fresh impact site.[23]
OppositionsJuno reaches opposition from the Sun every 15.5 months or so, with its minimum distance varying greatly depending on whether it is near perihelion or aphelion. Sequences of favorable oppositions occur every 10th opposition, i.e. just over every 13 years. The last favorable oppositions were on December 1, 2005 at a distance of 1.063 AU, magnitude 7.55, and on November 17, 2018 at a minimum distance of 1.036 AU, magnitude 7.45.[30][31] The next opposition will be October 30, 2031, at a distance of 1.044 AU, magnitude 7.42. See also
Notes{{notelist}}References1. ^{{OED|Junonian}} 2. ^{{cite web |title=AstDyS-2 Juno Synthetic Proper Orbital Elements |publisher=Department of Mathematics, University of Pisa, Italy |url=http://hamilton.dm.unipi.it/astdys/index.php?pc=1.1.6&n=3 |accessdate=2011-10-01}} 3. ^{{cite journal |doi=10.1016/j.icarus.2004.08.005 |url=http://www.mit.edu/people/lucylim/2005_Icarus_LimMcConnochie_Thermal_infrared_8-13_micron_spectra.pdf|title=Thermal infrared (8?13 ?m) spectra of 29 asteroids: The Cornell Mid-Infrared Asteroid Spectroscopy (MIDAS) Survey|journal=Icarus|volume=173|issue=2|pages=385|year=2005|last1=Lim|first1=L|last2=McConnochie|first2=T|last3=Belliii|first3=J|last4=Hayward|first4=T|bibcode=2005Icar..173..385L}} 4. ^1 2 Calculated based on the known parameters 5. ^1 2 3 4 {{cite web |date=2008 |title=Recent Asteroid Mass Determinations |publisher=Personal Website |author=Jim Baer |url=http://home.earthlink.net/~jimbaer1/astmass.txt |accessdate=2008-12-03}} 6. ^ {{cite web |editor-last=Harris |editor-first=A. W. |editor2=Warner, B. D. |editor3=Pravec, P. |title=Asteroid Lightcurve Derived Data. EAR-A-5-DDR-DERIVED-LIGHTCURVE-V8.0. |publisher=NASA Planetary Data System |date=2006 |url=http://www.psi.edu/pds/resource/lc.html |accessdate=2007-03-15 |archiveurl=https://www.webcitation.org/5mqof7MU9?url=http://www.psi.edu/pds/resource/lc.html |archivedate=January 17, 2010 |deadurl=yes |df= }} 7. ^{{cite web | editor-last= Neese | editor-first= C. | title= Asteroid Taxonomy.EAR-A-5-DDR-TAXONOMY-V5.0. | publisher= NASA Planetary Data System | date= 2005 | url= http://www.psi.edu/pds/asteroid/EAR_A_5_DDR_TAXONOMY_V5_0/data/taxonomy05.tab | archive-url= https://web.archive.org/web/20060905083536/http://www.psi.edu/pds/asteroid/EAR_A_5_DDR_TAXONOMY_V5_0/data/taxonomy05.tab | dead-url= yes | archive-date= 2006-09-05 | accessdate= 2013-12-24}} 8. ^{{cite web |title=AstDys (3) Juno Ephemerides |publisher=Department of Mathematics, University of Pisa, Italy |url=http://hamilton.dm.unipi.it/astdys/index.php?pc=1.1.3.1&n=3&oc=500&y0=1983&m0=10&d0=23&h0=00&mi0=00&y1=1983&m1=10&d1=26&h1=00&mi1=00&ti=1.0&tiu=days |accessdate=2010-06-26}} 9. ^{{cite web |title=Bright Minor Planets 2005 |publisher=Minor Planet Center|url=http://www.cfa.harvard.edu/iau/Ephemerides/Bright/2005 |deadurl=yes |archiveurl=https://web.archive.org/web/20080929074506/http://www.cfa.harvard.edu/iau/Ephemerides/Bright/2005/ |archivedate=2008-09-29}} 10. ^1 {{cite web |editor-last=Davis |editor-first=D. R. |editor2=Neese, C. |title=Asteroid Albedos. EAR-A-5-DDR-ALBEDOS-V1.1. |publisher=NASA Planetary Data System |date=2002 |url=http://www.psi.edu/pds/resource/albedo.html |accessdate=2007-02-18 |archiveurl=https://www.webcitation.org/5mqof7ROl?url=http://www.psi.edu/pds/resource/albedo.html |archivedate=January 17, 2010 |deadurl=yes |df= }} 11. ^1 {{cite journal | last= Lim | first= Lucy F. |author2= McConnochie, Timothy H.|author3= Bell, James F.|author4= Hayward, Thomas L. | title= Thermal infrared (8–13 µm) spectra of 29 asteroids: the Cornell Mid-Infrared Asteroid Spectroscopy (MIDAS) Survey | journal= Icarus | date= 2005 | volume= 173 | issue= 2| pages= 385–408 | bibcode= 2005Icar..173..385L | doi= 10.1016/j.icarus.2004.08.005}} 12. ^ {{cite journal |last=Pitjeva |first=E. V. |authorlink=Elena V. Pitjeva |title=High-Precision Ephemerides of Planets—EPM and Determination of Some Astronomical Constants |journal=Solar System Research |date=2005 |volume=39 |issue=3 |page=176 |url=http://iau-comm4.jpl.nasa.gov/EPM2004.pdf |format=PDF |doi=10.1007/s11208-005-0033-2 |bibcode=2005SoSyR..39..176P |deadurl=yes |archiveurl=https://web.archive.org/web/20081031065523/http://iau-comm4.jpl.nasa.gov/EPM2004.pdf |archivedate=2008-10-31 |df= }} 13. ^{{cite web | author=Hilton, James L. |title=When did the asteroids become minor planets? |work=U.S. Naval Observatory |url=http://aa.usno.navy.mil/faq/docs/minorplanets.php |accessdate=2008-05-08 |archiveurl = https://web.archive.org/web/20080324182332/http://aa.usno.navy.mil/faq/docs/minorplanets.php |archivedate = 2008-03-24}} 14. ^Pitjeva, E. V.; Precise determination of the motion of planets and some astronomical constants from modern observations, in Kurtz, D. W. (Ed.), Proceedings of IAU Colloquium No. 196: Transits of Venus: New Views of the Solar System and Galaxy, 2004 15. ^{{cite web|title=Comets Asteroids |url=http://comets-asteroids.findthedata.org/l/3015/3-Juno |archive-url=https://archive.is/20140514074257/http://comets-asteroids.findthedata.org/l/3015/3-Juno |dead-url=yes |archive-date=14 May 2014 |publisher=Find The Data.org |accessdate=14 May 2014 }} 16. ^ {{cite web |title=The Brightest Asteroids |publisher=The Jordanian Astronomical Society |author=Odeh, Moh'd |url=http://jas.org.jo/ast.html |accessdate=2008-05-21 |archiveurl=https://web.archive.org/web/20080511115437/http://www.jas.org.jo/ast.html |archivedate=11 May 2008 |deadurl=yes |df= }} 17. ^ {{cite web|date=2004 |title=What Can I See Through My Scope? |publisher=Ballauer Observatory |url=http://www.allaboutastro.com/Articlepages/whatcanisee.html |accessdate=2008-07-20 |deadurl=yes |archiveurl=https://web.archive.org/web/20110726123615/http://www.allaboutastro.com/Articlepages/whatcanisee.html |archivedate=July 26, 2011 }} (archived) 18. ^1 {{cite web |date=2007-11-16 |author=Hilton, James L |authorlink=James L. Hilton |title=When did asteroids become minor planets? |work=U.S. Naval Observatory |url=http://aa.usno.navy.mil/faq/docs/minorplanets.php |accessdate=2008-06-22 |archiveurl = https://web.archive.org/web/20080324182332/http://aa.usno.navy.mil/faq/docs/minorplanets.php |archivedate = 2008-03-24}} 19. ^{{cite web|title=MBA Eccentricity Screen Capture |publisher=JPL Small-Body Database Search Engine |url=http://home.comcast.net/~kpheider/3Juno-ecc.jpg |accessdate=2008-11-01 |deadurl=yes |archiveurl=https://web.archive.org/web/20090327111705/http://home.comcast.net/~kpheider/3Juno-ecc.jpg |archivedate=March 27, 2009 }} 20. ^The north pole points towards ecliptic coordinates (β, λ) = (27°, 103°) within a 10° uncertainty. {{cite journal | last= Kaasalainen | first= M. |author2= Torppa, J.|author3= Piironen, J. | title= Models of Twenty Asteroids from Photometric Data | journal= Icarus | volume= 159 | issue= 2 | pages= 369–395 | date= 2002 | url= http://www.rni.helsinki.fi/~mjk/IcarPIII.pdf | format= PDF | doi= 10.1006/icar.2002.6907 | bibcode=2002Icar..159..369K}} 21. ^{{cite journal | last= Gaffey | first= Michael J. |author2=Burbine, Thomas H.|author3=Piatek, Jennifer L.|author4=Reed, Kevin L.|author5=Chaky, Damon A.|author6=Bell, Jeffrey F.|author7= Brown, R. H. | title= Mineralogical variations within the S-type asteroid class | journal= Icarus | date= 1993 | volume= 106 | issue= 2 | page= 573 | bibcode= 1993Icar..106..573G | doi= 10.1006/icar.1993.1194}} 22. ^ {{cite web |title=Asteroid Juno Has A Bite Out Of It |publisher=Harvard-Smithsonian Center for Astrophysics |date=2003-08-06 |url=http://cfa-www.harvard.edu/press/pr0318.html |accessdate=2007-02-18 |archiveurl=https://web.archive.org/web/20070208013152/http://cfa-www.harvard.edu/press/pr0318.html |archivedate=8 February 2007 |deadurl=yes }} 23. ^1 {{cite journal |last=Baliunas |first=Sallie |author2=Donahue, Robert |author3=Rampino, Michael R. |author4=Gaffey, Michael J. |author5=Shelton, J. Christopher |author6=Mohanty, Subhanjoy |title=Multispectral analysis of asteroid 3 Juno taken with the 100-inch telescope at Mount Wilson Observatory |journal=Icarus |date=2003 |volume=163 |issue=1 |pages=135–141 |url=https://pubs.giss.nasa.gov/docs/2003/2003_Baliunas_ba04100j.pdf |format=PDF |doi=10.1016/S0019-1035(03)00049-6 |bibcode=2003Icar..163..135B }} 24. ^{{cite journal |doi=10.1016/j.icarus.2004.08.005 |url=http://www.mit.edu/people/lucylim/2005_Icarus_LimMcConnochie_Thermal_infrared_8-13_micron_spectra.pdf|title=Thermal infrared (8?13 ?m) spectra of 29 asteroids: The Cornell Mid-Infrared Asteroid Spectroscopy (MIDAS) Survey|journal=Icarus|volume=173|issue=2|pages=385|year=2005|last1=Lim|first1=L|last2=McConnochie|first2=T|last3=Belliii|first3=J|last4=Hayward|first4=T|bibcode=2005Icar..173..385L}} 25. ^ {{cite journal | display-authors= 8 | last= Millis | first= R. L. | author2= Wasserman, L. H. | author3= Bowell, E. | author4= Franz, O. G. | author5= White, N. M. | author6= Lockwood, G. W. | author7= Nye, R. | author8= Bertram, R. | author9= Klemola, A. | author10= Dunham, E. | author11= Morrison, D. | title= The diameter of Juno from its occultation of AG+0°1022 | journal= Astronomical Journal | volume= 86 | pages= 306–313 |date=February 1981 | bibcode= 1981AJ.....86..306M | doi= 10.1086/112889}} 26. ^[https://archive.is/20130729233004/http://www.asteroidoccultation.com/2013_07/0729_3_30531.htm Asteroid Occultation Updates – Jul 29, 2013] 27. ^[https://archive.is/20130729232944/http://www.asteroidoccultation.com/2013_07/0730_3_29995.htm Asteroid Occultation Updates – Jul 30, 2013]. 28. ^ {{cite conference | first=E. V. | last= Pitjeva | title= Estimations of masses of the largest asteroids and the main asteroid belt from ranging to planets, Mars orbiters and landers | booktitle= 35th COSPAR Scientific Assembly. Held 18–25 July 2004, in Paris, France | pages= 2014 | date= 2004 | bibcode= 2004cosp...35.2014P}} 29. ^{{cite journal |last=Hilton |first=James L. |title=US Naval Observatory Ephemerides of the Largest Asteroids |journal= Astronomical Journal |volume=117 |issue=2 |pages=1077–1086 |date=February 1999 |url=http://aa.usno.navy.mil/publications/reports/asteroid_ephemerides.html |doi=10.1086/300728 |bibcode=1999AJ....117.1077H |accessdate=2012-04-15}} 30. ^The Astronomical Amanac for the year 2018, G14 31. ^[https://in-the-sky.org/news.php?id=20181116_14_100 Asteroid 3 Juno at opposition] 16 Nov 2018 at 11:31 UTC }} External links{{Commons|3 Juno|3 Juno}}
9 : Juno asteroids|Discoveries by Karl Harding|Minor planets named from Roman mythology|Named minor planets|Articles containing video clips|S-type asteroids (Tholen)|Sk-type asteroids (SMASS)|Astronomical objects discovered in 1804|Objects observed by stellar occultation |
||||||||||||||||||||||||||
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。