Discovery [1] | |
---|---|
Discovered by | M. F. Wolf |
Discovery site | Heidelberg Obs. |
Discovery date | 14 January 1905 |
Designations | |
(555) Norma | |
Pronunciation | Italian: [ˈnɔrma] [2] |
Named after | Norma (character in Bellini's opera) [3] |
1905 PT ·1928 FS 1939 BA ·1950 CC 1954 UH2 ·1968 HE1 | |
main-belt ·(outer) · background [4] | |
Orbital characteristics [1] | |
Epoch 4 September 2017 (JD 2458000.5) | |
Uncertainty parameter 0 | |
Observation arc | 112.20 yr (40,981 days) |
Aphelion | 3.6636 AU |
Perihelion | 2.7105 AU |
3.1870 AU | |
Eccentricity | 0.1495 |
5.69 yr (2,078 days) | |
343.66° | |
0° 10m 23.52s / day | |
Inclination | 2.6462° |
130.43° | |
356.51° | |
Physical characteristics | |
Dimensions | 27.89±0.68 km [5] 31.040±0.150 km [6] 31.80±0.58 km [7] 32.541±0.215 km [8] 33±3 km [9] 33.0±3.3 km [10] 40.02 km (derived) [4] 40.11±1.5 km [11] |
19.508±0.002 h [12] 19.55±0.01 h [13] 30.6±0.5 h [14] | |
0.0528 (derived) [4] 0.0632±0.005 [11] 0.08±0.02 [10] 0.09±0.02 [9] 0.0962±0.0150 [8] 0.101±0.004 [7] 0.119±0.018 [5] | |
SMASS = B [1] · B [9] [15] C [4] | |
10.37±0.26 [16] ·10.6 [7] [8] [11] ·10.70 [5] [9] ·10.8 [1] [4] [10] | |
Norma (minor planet designation: 555 Norma), provisional designation 1905 PT, is a background asteroid from the outer regions of the asteroid belt, approximately 33 kilometers in diameter. It was discovered on 14 January 1905, by German astronomer Max Wolf at Heidelberg Observatory in southwest Germany. [17] The asteroid was named after the title character of Bellini's opera Norma . [3]
Norma is a background asteroid, located near the region occupied by the Themis family, a prominent family of outer-belt asteroids with nearly coplanar ecliptical orbits. It orbits the Sun at a distance of 2.7–3.7 AU once every 5 years and 8 months (2,078 days). Its orbit has an eccentricity of 0.15 and an inclination of 3° with respect to the ecliptic. [1] The body's observation arc begins at Heidelberg in March 1911, more than six years after its official discovery observation. [17]
In the SMASS classification, Norma is a B-type asteroid. These types of asteroids have a featureless surface that displays magnesium-rich silicates, which likely accounts for the relatively high albedo as an outer-belt asteroid. Norma surface consists of more than 50% amorphous magnesium pyroxenes based on data collected with the Subaru Telescope. [15]
In April 2007, a first rotational lightcurve of Norma was obtained from photometric observations by French amateur astronomer Pierre Antonini. Lightcurve analysis gave a rotation period of 30.6 hours with a brightness variation of 0.2 magnitude ( U=2 ). [14] However more recent observations by two American astronomers have since superseded this result.
In December 2011, Robert Stephens at the Santana Observatory ( 646 ) obtained a lightcurve that gave a period 19.55 hours and a brightness amplitude of 0.06 magnitude ( U=2+ ), while Frederick Pilcher measured a period of 19.508 hours with an amplitude of 0.25 at the Organ Mesa Observatory ( G50 ) in November 2016. [12] [13]
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Norma measures between 27.89 and 40.11 kilometers in diameter and its surface has an albedo of between 0.063 and 0.119. [5] [6] [7] [8] [9] [10] [11]
The Collaborative Asteroid Lightcurve Link (CALL) agrees with IRAS, and derives an albedo of 0.0528 and a diameter of 40.02 kilometers based on an absolute magnitude of 10.8. CALL also assumes Norma to be a C-type asteroid (rather than a B-type) due to its derived low albedo and the general spectral type of the Themis family. [4]
This minor planet was named for the principal female character of the opera Norma by Italian composer Vincenzo Bellini (1801–1835). In the opera, Norma is a high priestess of the Druids. In 1955, the official naming citation was published by Paul Herget in The Names of the Minor Planets ( H 59 ) [3]
1743 Schmidt, provisional designation 4109 P-L, is a dark background asteroid from the inner regions of the asteroid belt, approximately 19 kilometers in diameter. It was discovered during the Palomar–Leiden survey on 24 September 1960, by astronomers Ingrid and Cornelis van Houten at Leiden, on photographic plates taken by Tom Gehrels at Palomar Observatory in California. The C-type asteroid has a rotation period of 17.5 hours. It was named for the optician Bernhard Schmidt.
Athalia, provisional designation 1903 ME, is a carbonaceous Themistian asteroid from the outer regions of the asteroid belt, approximately 40 kilometers in diameter. It was discovered on 20 September 1903, by German astronomer Max Wolf at the Heidelberg Observatory in southwest Germany. The asteroid was named after the ancient Judahite queen Athaliah.
Pawlowia, provisional designation 1923 OX, is a background asteroid from the central regions of the asteroid belt, approximately 20 kilometers in diameter. It was discovered on 5 October 1923, by Soviet astronomer Vladimir Albitsky at the Simeiz Observatory on the Crimean peninsula. The asteroid was named after Russian physiologist and Nobelist Ivan Pavlov.
La Paz, provisional designation 1923 PD, is a carbonaceous asteroid from the outer region of the asteroid belt, approximately 40 kilometers in diameter. It was discovered on 31 October 1923, by German astronomer Max Wolf at the Heidelberg-Königstuhl State Observatory and named after the city La Paz in Bolivia.
1074 Beljawskya, provisional designation 1925 BE, is a Themistian asteroid from the outer region of the asteroid belt, approximately 48 kilometers in diameter.
1132 Hollandia, provisional designation 1929 RB1, is a stony asteroid from the middle region of the asteroid belt, approximately 27 kilometers in diameter. It was discovered on 13 September 1929, by Dutch astronomer Hendrik van Gent at Leiden Southern Station, annex to the Johannesburg Observatory in South Africa. It was named for the region Holland in the Netherlands.
1159 Granada, provisional designation 1929 RD, is a dark background asteroid and relatively slow rotator from the inner regions of the asteroid belt, approximately 30 kilometers in diameter. It was discovered on 2 September 1929, by astronomer Karl Reinmuth at the Heidelberg Observatory in southwest Germany. The asteroid was named for the Spanish city and province of Granada.
(9928) 1981 WE9, provisional designation 1981 WE9, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 3 kilometers in diameter. It was discovered on 16 November 1981, by astronomers at Perth Observatory in Bickley, Australia.
6349 Acapulco, provisional designation 1995 CN1, is a dark Adeonian asteroid from the middle region of the asteroid belt, approximately 22 kilometers in diameter.
1555 Dejan, provisional designation 1941 SA, is an asteroid from the background population of the central regions of the asteroid belt, approximately 22 kilometers in diameter. It was discovered on 15 September 1941, by Belgian astronomer Fernand Rigaux at the Royal Observatory of Belgium in Uccle. The asteroid was named after Dejan Đurković, son of Serbian astronomer Petar Đurković.
1241 Dysona, provisional designation 1932 EB1, is a dark background asteroid from the outer regions of the asteroid belt, approximately 77 kilometers in diameter. It was discovered on 4 March 1932, by English astronomer Harry Edwin Wood at the Union Observatory in Johannesburg, South Africa. The asteroid was named after English astronomer Frank Watson Dyson.
1541 Estonia, provisional designation 1939 CK, is an asteroid from the central regions of the asteroid belt, approximately 21 kilometers in diameter. It was discovered on 12 February 1939, by astronomer Yrjö Väisälä at the Iso-Heikkilä Observatory near Turku, Finland. The asteroid was named after the Baltic country of Estonia.
1267 Geertruida, provisional designation 1930 HD, is a carbonaceous background asteroid from the inner regions of the asteroid belt, approximately 20 kilometers in diameter. Discovered by astronomer Hendrik van Gent at Johannesburg Observatory in 1930, the asteroid was later named after Geertruid Pels, sister of Dutch astronomer Gerrit Pels.
2126 Gerasimovich, provisional designation 1970 QZ, is a stony background asteroid from the inner regions of the asteroid belt, approximately 8 kilometers in diameter. It was discovered on 30 August 1970, by Soviet astronomer Tamara Smirnova at the Crimean Astrophysical Observatory in Nauchnyj, on the Crimean peninsula. The asteroid was named after Russian astronomer Boris Gerasimovich.
1384 Kniertje, provisional designation 1934 RX, is a dark Adeonian asteroid from the central regions of the asteroid belt, approximately 26 kilometers in diameter. It was discovered on 9 September 1934, by Dutch astronomer Hendrik van Gent at the Union Observatory in Johannesburg, South Africa. The asteroid was named after a character in the Dutch play Op Hoop van Zegen by Herman Heijermans.
2043 Ortutay, provisional designation 1936 TH, is a dark asteroid from the outer regions of the asteroid belt, approximately 45 kilometers in diameter. The asteroid was discovered by Hungarian astronomer György Kulin at the Konkoly Observatory, Budapest, on 12 November 1936. It was named after Hungarian ethnographer Gyula Ortutay.
1405 Sibelius, provisional designation 1936 RE, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 8 kilometers in diameter. It was discovered on 12 September 1936, by Finnish astronomer Yrjö Väisälä at Turku Observatory in Southwest Finland. The asteroid was named after composer Jean Sibelius.
1323 Tugela, provisional designation 1934 LD, is a dark background asteroid from the outer regions of the asteroid belt, approximately 60 kilometers in diameter. It was discovered on 19 May 1934, by South African astronomer Cyril Jackson at the Union Observatory in Johannesburg. The asteroid was named for the Tugela River in western South Africa.
2120 Tyumenia is a dark background asteroid, approximately 45 kilometers in diameter, located in the outer regions of the asteroid belt. It was discovered on 9 September 1967, by Soviet astronomer Tamara Smirnova at the Crimean Astrophysical Observatory in Nauchnyj, on the Crimean peninsula. The asteroid was named for the now Russian district of Tyumen Oblast in Western Siberia.
1544 Vinterhansenia, provisional designation 1941 UK, is a dark asteroid from the inner regions of the asteroid belt, approximately 22 kilometers in diameter. It was discovered on 15 October 1941, by Finnish astronomer Liisi Oterma at Turku Observatory in Southwest Finland, and named for Danish astronomer Julie Vinter Hansen.