Ophelia
- För andra betydelser, se Ophelia (olika betydelser).
| Ophelia | |
 Ophelias upptäcktsbild | |
| Upptäckt | |
|---|---|
| Upptäckare | Richard J. Terrile / Voyager 2 |
| Upptäcktsdatum | 20 januari, 1986 |
| Beteckningar | |
| Alternativnamn | S/1986 U 8 |
| Uppkallad efter | Ofelia |
| Omloppsbana | |
| Halv storaxel | 53 763,390 ± 0,847 km[1] |
| Excentricitet | 0,00992 ± 0,000107[1] |
| Siderisk omloppstid | 0,37640039 ± 0,00000357 d[1] |
| Inklination | 0,10362 ± 0,055° (till Uranus ekvator)[1] |
| Måne till | Uranus |
| Fysikaliska data | |
| Dimensioner | 54 × 38 × 38 km[2] |
| Area | ~6600 km² |
| Volym | ~41 000 km³ |
| Massa | ~5,1 × 1016 kg |
| Medeldensitet | ~1,3 g/cm³ |
| Ytgravitation (ekvatorn) | ~0,0070 m/s² |
| Flykthastighet | ~0,018 km/s |
| Rotationsperiod | Bunden rotation[2] |
| Albedo | 0,08 ± 0,01[3] |
| Temperatur | ~64 K |
| Skenbar magnitud | +23,26 [4] |
| Hitta fler artiklar om astronomi med | |
Ophelia är en av Uranus månar. Den upptäcktes 1986 vid passagen av den amerikanska rymdsonden Voyager 2, och fick den tillfälliga beteckningen S/1986 U 8. Den är också betecknad Uranus VII.
Ophelia är uppkallad efter Polonius dotter i William Shakespeares pjäs Hamlet.
Man vet knappt någonting annat om Ophelia än om dess omloppsbana[1], dess radie på 23 km[2] och den geometriska albedon på 0,08[3]. På bilder tagna av Voyager 2, så ser Cordelia ut att vara avlång till formen, den längre axeln pekar mot Uranus. Axelvärderna av Cordelias form är 0,7 ± 0,3.[2]
Cordelia agerar som en inre herdemåne till Uranus Epsilonring.[5]
Källor
- ^ [a b c d e] Jacobson, R.A. (12 december 1998). ”The Orbits of the Inner Uranian Satellites From Hubble Space Telescope and Voyager2 Observations”. The Astronomical Journal "115": ss. 1195-1199. doi:. http://adsabs.harvard.edu/abs/1998AJ....115.1195J.
- ^ [a b c d] Karkoschka, Erich (12 december 2001). ”Voyager's Eleventh Discovery of a Satellite of Uranus and Photometry and the First Size Measurements of Nine Satellites”. Icarus "151": ss. 69–77. doi:. http://adsabs.harvard.edu/abs/2001Icar..151...69K.
- ^ [a b] Karkoschka, Erich (12 december 2001). ”Comprehensive Photometry of the Rings and 16 Satellites of Uranus with the Hubble Space Telescope”. Icarus "151": ss. 51–68. doi:. http://adsabs.harvard.edu/abs/2001Icar..151...51K.
- ^ Britt Gynther och Stig Carlson (2006). Faktakalendern 2007. Semic. sid. 79
- ^ Esposito, L. W. (12 december 2002). ”Planetary rings”. Reports On Progress In Physics "65": ss. 1741–1783. Arkiverad från originalet den 16 juni 2020. https://web.archive.org/web/20200616073630/https://hkvalidate.perfdrive.com/captcha?ssa=c3f22f43-1b05-49c0-b512-7258ce109b98&ssb=b64mpk1g5zpk0pp5bmpd0f3mz&ssc=http%3A%2F%2Fiopscience.iop.org%2F%2Fabstract%2F0034-4885%2F65%2F12%2F201&ssd=032429776486416&sse=ibp%40fjiladmlmla&ssf=9fdb51f1252be180d3e222fb0dbf4ad8778eb4a8&ssg=58694441-d665-4a78-b37d-4e1dbbd2fa5c&ssh=fae5edf9-5b78-4210-a145-35ee8afc4da9&ssi=3f116cc7-8427-4cba-8b75-678e2866c8be&ssj=20e6779a-ad69-4f41-95b7-190ac5d1c1dc&ssk=support%40shieldsquare.com&ssl=418220199399&ssm=86089471003809836105874142622933&ssn=db07be1a67518e02f2626518d3373803edf393e9393d-ef9e-4944-868f79&sso=ce31f39e-50d966be57a2329d20682f0ee7c0781127111e979c9e3b47&ssp=13036241841592253725159221755409225&ssq=61709339299082377220792990853922990208194&ssr=MjA3LjI0MS4yMjUuMTU5&sss=Mozilla%2F5.0%20%28compatible%3B%20Googlebot%2F2.1%3B%20+http%3A%2F%2Fwww.google.com%2Fbot.html%29&sst=Mozilla%2F5.0%20%28Windows%20NT%2010.0%3B%20Win64%3B%20x64%29%20AppleWebKit%2F537.36%20%28KHTML%2C%20like%20Gecko%29%20Chrome%2F74.0.3729.169%20Safari%2F537.36&ssu=Chrome%2F5.0%20%28iPhone%3B%20U%3B%20CPU%20iPhone%20OS%203_0%20like%20Mac%20OS%20X%3B%20en-us%29%20AppleWebKit%2F528.18%20%28KHTML%2C%20like%20Gecko%29%20Version%2F4.0%20Mobile%2F7A341%20Safari%2F528.16&ssv=v34vumln3ur3943&ssw=&ssx=126968914553564&ssy=hcj%40hjhmokckfgfdkj%40jolcjd%40jojlccdnopmbc%40&ssz=449466d2a20b056. Läst 30 november 2007.
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Uranus rings and two moons.jpg
Original Caption Released with Image:
Voyager 2 has discovered two "shepherd" satellites associated with the rings of Uranus. The two moons -- designated 1986U7 and 1986U8 -- are seen here on either side of the bright epsilon ring; all nine of the known Uranian rings are visible. The image was taken Jan. 21, 1986, at a distance of 4.1 million kilometers (2.5 million miles) and resolution of about 36 km (22 mi). The image was processed to enhance narrow features. The epsilon ring appears surrounded by a dark halo as a result of this processing; occasional blips seen on the ring are also artifacts. Lying inward from the epsilon ring are the delta, gamma and eta rings; then the beta and alpha rings; and finally the barely visible 4, 5 and 6 rings. The rings have been studied since their discovery in 1977, through observations of how they diminish the light of stars they pass in front of. This image is the first direct observation of all nine rings in reflected sunlight. They range in width from about 100 km (60 mi) at the widest part of the epsilon ring to only a few kilometers for most of the others. The discovery of the two ring moons 1986U7 and 1986U8 is a major advance in our understanding of the structure of the Uranian rings and is in good agreement with theoretical predictions of how these narrow rings are kept from spreading out. Based on likely surface brightness properties, the moons are of roughly 2O- and 3O-km diameter, respectively. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.