54 Alexandra

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54 Alexandra
54Alexandra (Lightcurve Inversion).png
A three-dimensional model of 54 Alexandra based on its light curve
Discovery [1]
Discovered by H. Goldschmidt
Discovery date10 September 1858
Designations
(54) Alexandra
Pronunciation /ˌælɪɡˈzændrə,-ˈzɑːn-/ AL-ig-ZA(H)N-drə [2]
Named after
Alexander von Humboldt
(German explorer)
Main belt
Adjectives Alexandrian
Orbital characteristics
Epoch December 31, 2006 (JD 2454100.5)
Aphelion 485.483 Gm (3.245 AU)
Perihelion 326.043 Gm (2.179 AU)
405.763 Gm (2.712 AU)
Eccentricity 0.196
1,631.620 d (4.47  a)
103.809°
Inclination 11.804°
313.446°
345.594°
Physical characteristics
Dimensions160 × 135 km (± 1 km)
Mean diameter
154.137 km [1]
Mass (6.16±3.50)×1018 kg [3]
Mean density
3.50±2.11 g/cm3 [3]
18.14 h [4]
155°± [5]
17°± [5]
0.056 [1] [6]
Tholen = C [1]
SMASS = C [1]
7.66 [1]

    Alexandra (minor planet designation: 54 Alexandra) is a carbonaceous asteroid from the intermediate asteroid belt, approximately 155 kilometers in diameter. It was discovered by German-French astronomer Hermann Goldschmidt on 10 September 1858, and named after the German explorer Alexander von Humboldt; it was the first asteroid to be named after a male. [7]

    Contents

    Description

    On May 17, 2005, this asteroid occulted a faint star (magnitude 8.5) and the event was observed and timed in a number of locations within the U.S. and Mexico. As a result, a silhouette profile was produced, yielding a roughly oval cross-section with dimensions of 160 × 135 km (± 1 km). [8] The mass of the asteroid can be estimated based upon the mutually perturbing effects of other bodies, yielding an estimate of (6.16±3.50)×1018 kg. [3]

    Photometric observations of this asteroid during 1990–92 gave a light curve with a period of 18.14 ± 0.04 hours and a brightness variation of 0.10 in magnitude. [4] Alexandra has been studied by radar. [9] It was the namesake and largest member of the former Alexandra asteroid family; a dynamic group of C-type asteroids that share similar orbital elements. Other members included 70 Panopaea and 145 Adeona. [10] 145 Adeona was subsequently assigned to the Adeona family, with Alexandra and Panopaea being dropped. [11]

    In the Swedish film Aniara (2018) it is mentioned that 54 Alexandra is the closest celestial body which the off-course and out-of-control spacecraft will approach before it leaves the Solar System.

    Related Research Articles

    <span class="mw-page-title-main">51 Nemausa</span> Main-belt asteroid

    Nemausa is a large main-belt asteroid that was discovered on January 22, 1858, by Joseph Jean Pierre Laurent. Laurent made the discovery from the private observatory of Benjamin Valz in Nîmes, France. The house, at 32 rue Nationale in Nîmes, has a plaque commemorating the discovery. With Laurent's permission, Valz named the asteroid after the Celtic god Nemausus, the patron god and namesake of Nîmes during Roman times.

    <span class="mw-page-title-main">11 Parthenope</span> Main-belt asteroid

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    <span class="mw-page-title-main">13 Egeria</span> Main-belt asteroid

    Egeria is a large main-belt G-type asteroid. It was discovered by Annibale de Gasparis on November 2, 1850. Egeria was named by Urbain Le Verrier, whose computations led to the discovery of Neptune, after the mythological nymph Egeria of Aricia, Italy, the wife of Numa Pompilius, second king of Rome.

    <span class="mw-page-title-main">18 Melpomene</span> Main-belt asteroid

    Melpomene is a large, bright main-belt asteroid that was discovered by J. R. Hind on 24 June 1852, and named after Melpomenē, the Muse of tragedy in Greek mythology. Its historical symbol was a dagger over a star; it is in the pipeline for Unicode 17.0 as U+1CECB 𜻋.

    <span class="mw-page-title-main">36 Atalante</span> Main-belt asteroid

    Atalante is a large, dark main-belt asteroid. It was discovered by the German-French astronomer H. Goldschmidt on October 5, 1855, and named by French mathematician Urbain Le Verrier after the Greek mythological heroine Atalanta. It was rendered 'Atalanta' in English sources in the 19th century. This asteroid is classified as C-type (carbonaceous), according to the Tholen classification system.

    <span class="mw-page-title-main">41 Daphne</span> Main-belt asteroid

    Daphne is a large asteroid from the asteroid belt. It is a dark-surfaced body 174 km in diameter is probably composed of primitive carbonaceous chondrites. The spectra of the asteroid displays evidence of aqueous alteration. It was discovered by H. Goldschmidt on May 22, 1856, and named after Daphne, the nymph in Greek mythology who was turned into a laurel tree. Incorrect orbital calculations initially resulted in 56 Melete being mistaken for a second sighting of Daphne. Daphne was not sighted again until August 31, 1862.

    <span class="mw-page-title-main">49 Pales</span> Main-belt asteroid

    Pales is a large, dark main-belt asteroid. It was discovered by German-French astronomer Hermann Goldschmidt on 19 September 1857 from his balcony in Paris. The asteroid is named after Pales, the goddess of shepherds in Roman mythology. Since it was discovered on the same night as 48 Doris, geologist Élie de Beaumont suggested naming the two "The Twins".

    <span class="mw-page-title-main">56 Melete</span> Large, dark, P-type main-belt asteroid

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    <span class="mw-page-title-main">70 Panopaea</span> Main-belt asteroid

    Panopaea is a large main belt asteroid. Its orbit is close to those of the Eunomia asteroid family; however, Panopaea is a dark, primitive carbonaceous C-type asteroid in contrast to the S-type asteroids of the Eunomian asteroids. The spectra of the asteroid displays evidence of aqueous alteration. Photometric studies give a rotation period of 15.797 hours and an amplitude of 0.11±0.01 in magnitude. Previous studies that suggested the rotation period may be twice this amount were rejected based upon further observation.

    <span class="mw-page-title-main">77 Frigga</span> Main-belt asteroid

    Frigga is a large, M-type, possibly metallic main-belt asteroid. It was discovered by the German-American astronomer C. H. F. Peters on November 12, 1862. The object is named after Frigg, the Norse goddess. The asteroid is orbiting the Sun with a period of 4.36 years and completes a rotation on its axis every nine hours.

    <span class="mw-page-title-main">102 Miriam</span> Main-belt asteroid

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    <span class="mw-page-title-main">145 Adeona</span> Main-belt asteroid

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    <span class="mw-page-title-main">161 Athor</span> Main-belt asteroid

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    <span class="mw-page-title-main">211 Isolda</span> Main-belt asteroid

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    <span class="mw-page-title-main">275 Sapientia</span> Main-belt asteroid

    Sapientia is a very large Main belt asteroid that was discovered by Johann Palisa on 15 April 1888 in Vienna. It is classified as a C-type asteroid and is probably composed of carbonaceous material. It is named for the Roman personification of wisdom, Sapientia.

    <span class="mw-page-title-main">402 Chloë</span> Main-belt asteroid

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    References

    1. 1 2 3 4 5 6 Yeomans, Donald K. "54 Alexandra". JPL Small-Body Database Browser. NASA Jet Propulsion Laboratory . Retrieved 7 April 2013.
    2. "Alexandra". Lexico UK English Dictionary. Oxford University Press. Archived from the original on 22 March 2020.
      "Alexandra". Dictionary.com Unabridged (Online). n.d.
    3. 1 2 3 Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science, vol. 73, pp. 98–118, arXiv: 1203.4336 , Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009. See Table 1.
    4. 1 2 Belskaya, I. N.; et al. (November 1993), "Physical Studies of Asteroids. Part XXVII. Photoelectric Photometry of Asteroids 14 Irene, 54 Alexandra and 56 Melete", Astronomy and Astrophysics Supplement, vol. 101, no. 3, pp. 507–511, Bibcode:1993A&AS..101..507B.
    5. 1 2 Hanuš, J.; et al. (May 2017), "Volumes and bulk densities of forty asteroids from ADAM shape modeling", Astronomy & Astrophysics, 601: 41, arXiv: 1702.01996 , Bibcode:2017A&A...601A.114H, doi:10.1051/0004-6361/201629956, A114.
    6. "Asteroid Data Sets". Archived from the original on 17 December 2009. Retrieved 12 January 2007.
    7. Schmadel, Lutz D. (2003), Dictionary of Minor Planet Names (5th ed.), Springer, p. 20, ISBN   3642297188.
    8. D.W. Dunham, "Upcoming Asteroid Occultations", Sky & Telescope, June, 2006, p. 63.
    9. "Radar-Detected Asteroids and Comets". NASA/JPL Asteroid Radar Research. Retrieved 30 October 2011.
    10. Williams, J. G. (March 1988), "The Unusual Alexandra Family", Abstracts of the Lunar and Planetary Science Conference, vol. 19, pp. 1277–1278, Bibcode:1988LPI....19.1277W.
    11. Zappala, Vincenzo; et al. (December 1990), "Asteroid families. I - Identification by hierarchical clustering and reliability assessment", Astronomical Journal, vol. 100, pp. 2030–2046, 2045, Bibcode:1990AJ....100.2030Z, doi: 10.1086/115658 . See p. 2045 and family 44.