Astronomy:42 Isis
.png) A three-dimensional model of 42 Isis based on its light curve | |
| Discovery | |
|---|---|
| Discovered by | Norman Robert Pogson |
| Discovery date | 23 May 1856 |
| Designations | |
| (42) Isis | |
| Pronunciation | /ˈaɪsɪs/[1] |
| Named after | Isis Pogson |
| Minor planet category | Main belt |
| Adjectives | Isidian /aɪˈsɪdiən/[2] |
| Orbital characteristics | |
| Epoch 31 December 2006 (JD 2454100.5) | |
| |{{{apsis}}}|helion}} | 446.706 Gm (2.986 AU) |
| |{{{apsis}}}|helion}} | 283.890 Gm (1.898 AU) |
| 365.298 Gm (2.442 AU) | |
| Eccentricity | 0.223 |
| Orbital period | 1393.737 d (3.82 a) |
| Mean anomaly | 121.874° |
| Inclination | 8.530° |
| Longitude of ascending node | 84.398° |
| |{{{apsis}}}|helion}} | 2024-Oct-17 |
| 236.626° | |
| Physical characteristics | |
| Dimensions | 102.73±2.73 km[3] |
| Mass | (1.58±0.52)×1018 kg[3] |
| Mean density | 2.78±0.93 g/cm3 [3] |
| Rotation period | 13.59701 h[4] |
| Geometric albedo | 0.171 (geometric)[5] |
| S | |
| Apparent magnitude | 9.18[6] to 13.50 |
| Absolute magnitude (H) | 7.53 |
Isis, minor planet designation: 42 Isis, is a large main-belt asteroid, measuring 100.2 km in diameter with a stony (S-type) composition. It was discovered by English astronomer N.R. Pogson on 23 May 1856 at Oxford, and was his first asteroid discovery. The asteroid's name was chosen by Manuel John Johnson, director of the Radcliffe Observatory in Oxford. Although Isis is the name of an Egyptian goddess, the name was chosen in homage to Pogson's astronomer daughter, (Elizabeth) Isis Pogson.[7] In addition, the Isis is the stretch of the River Thames that runs through Oxford.[8]
This asteroid is orbiting the Sun with a period of 3.82 years. The light curve inversion technique, when applied to photometric observations of this asteroid, show multiple local irregularities. The overall shape displays little elongation, with a ratio between the major and minor axes equal to 1.1. The measured rotation period for this model is 13.6 hours.[4] The spectrum of 42 Isis reveals the strong presence of the mineral Olivine, a relative rarity in the asteroid belt.[9]
References
- ↑ Noah Webster (1884) A Practical Dictionary of the English Language
- ↑ E.g. Adriano La Regina ed. (2004) Archaeological Guide to Rome, p. 66. Cf. the pronunciation of isidium (3rd ed.), Oxford University Press, September 2005, http://oed.com/search?searchType=dictionary&q=isidium (Subscription or UK public library membership required.).
- ↑ 3.0 3.1 3.2 Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science 73 (1): 98–118, doi:10.1016/j.pss.2012.03.009, Bibcode: 2012P&SS...73...98C. See Table 1.
- ↑ 4.0 4.1 Torppa, Johanna et al. (August 2003), "Shapes and rotational properties of thirty asteroids from photometric data", Icarus 164 (2): 346–383, doi:10.1016/S0019-1035(03)00146-5, Bibcode: 2003Icar..164..346T.
- ↑ Asteroid Data Sets
- ↑ "AstDys (42) Isis Ephemerides". Department of Mathematics, University of Pisa, Italy. https://hamilton.dm.unipi.it/astdys/index.php?pc=1.1.3.1&n=42&oc=500&y0=1963&m0=7&d0=4&h0=0&mi0=0&y1=1963&m1=7&d1=4&h1=0&mi1=0&ti=1.0&tiu=days.
- ↑ Bruck, Mary (2009), Women in Early British and Irish Astronomy, Springer, pp. 157, ISBN 978-90-481-2472-5.
- ↑ Lutz D. Schmadel (2011). Dictionary of Minor Planet Names (Addendum to Fifth Edition: 2006–2008 ed.). Springer. ISBN 978-3-642-01966-1. https://books.google.com/books?id=uwGbkbhMVyAC.
- ↑ Burbine, T. H. et al. (July 2000), "The Nature of Olivine Asteroids", Meteoritics & Planetary Science 35: pp. A35, doi:10.1111/j.1945-5100.2000.tb01796.x, Bibcode: 2000M&PSA..35R..35B.
External links
- 42 Isis at AstDyS-2, Asteroids—Dynamic Site
- 42 Isis at the JPL Small-Body Database
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