Discovery [1] | |
---|---|
Discovered by | J. Palisa |
Discovery site | Vienna Obs. |
Discovery date | 27 August 1914 |
Designations | |
(794) Irenaea | |
Pronunciation | ⫽ɪrɪˈniːə⫽ [2] |
Named after | Irene Hillebrand, daughter of Edmund Weiss (Austrian astronomer ) [3] |
A914 QB ·1930 KH 1936 QK ·1947 QD 1953 TT2 ·1914 VB | |
Orbital characteristics [4] | |
Epoch 31 May 2020 (JD 2459000.5) | |
Uncertainty parameter 0 | |
Observation arc | 83.12 yr (30,360 d) |
Aphelion | 4.0559 AU |
Perihelion | 2.2004 AU |
3.1281 AU | |
Eccentricity | 0.2966 |
5.53 yr (2,021 d) | |
31.160° | |
0° 10m 41.16s / day | |
Inclination | 5.4193° |
160.40° | |
131.27° | |
Physical characteristics | |
9.14±0.01 h [12] | |
C (assumed) [5] | |
794 Irenaea (prov. designation: A914 QBor1914 VB) is a dark background asteroid from the outer regions of the asteroid belt. It was discovered on 27 August 1914, by Austrian astronomer Johann Palisa at the Vienna Observatory. [1] The presumed C-type asteroid has a rotation period of 9.1 hours and measures approximately 36 kilometers (22 miles) in diameter. It was likely named after Irene Hillebrand, daughter of Austrian astronomer Edmund Weiss (1837–1917). [3]
Irenaea is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements. [6] [7] [8] It orbits the Sun in the outer main-belt at a distance of 2.2–4.1 AU once every 5 years and 6 months (2,021 days; semi-major axis of 3.13 AU). Its orbit has an eccentricity of 0.30 and an inclination of 5° with respect to the ecliptic. [4] The body's observation arc begins at Bergedorf Observatory in Hamburg on 9 December 1915, more than a year after its official discovery observation at Vienna Observatory on 27 August 1914. [1]
According to Alexander Schnell, this minor planet was likely named after Irene Hillebrand, née Weiss, daughter of Austrian astronomer Edmund Weiss (1837–1917), director of the Vienna Observatory, and wife to astronomer Karl Hillebrand (1861–1939). The name received an aea-suffix as "Irene" was already given to asteroid 14 Irene. [3] Palisa also named asteroid 722 Frieda after her daughter, Frieda Hillebrand. [13]
Irenaea is an assumed, carbonaceous C-type asteroid. [5] The asteroid's low albedo around 0.05 (see below) agrees with this assumption.
In May 2008, a rotational lightcurve of Irenaea was obtained from photometric observations by Italian amateur astronomer Silvano Casulli. Lightcurve analysis gave a rotation period of 9.14±0.01 hours with a brightness variation of 0.40±0.02 magnitude, indicative of an elongated shape ( U=3− ). [12]
According to the surveys carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), the Infrared Astronomical Satellite IRAS, and the Japanese Akari satellite, Irenaea measures (35.703±6.145), (35.75±3.6) and (38.00±1.35) kilometers in diameter and its surface has an albedo of (0.046±0.018), (0.0502±0.012) and (0.045±0.004), respectively. [9] [10] [11] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for a carbonaceous C-type asteroid of 0.057 and calculates a diameter of 30.59 kilometers based on an absolute magnitude of 11.3. [5] Alternative mean diameter measurements published by the WISE team include (29.80±11.78 km ), (32.45±7.05 km) and (37.140±11.511 km) with corresponding albedos of (0.036±0.021), (0.06±0.04) and (0.05±0.02). [5] [7]
Stephania is a dark background asteroid from the inner regions of the asteroid belt, approximately 32 km (20 mi) in diameter. It was discovered on 19 May 1881, by Austrian astronomer Johann Palisa at the Vienna Observatory. The C-type asteroid has a rotation period of 18.2 hours. It was named after Princess Stéphanie of Belgium.
716 Berkeley is a background asteroid from the central regions of the asteroid belt. It was discovered by Austrian astronomer Johann Palisa at the Vienna Observatory on 30 July 1911. The stony S-type asteroid has a rotation period of 15.6 hours and measures approximately 21 kilometers in diameter. It was named after the city of Berkeley, California, where the discoverer's colleague Armin Otto Leuschner (1868–1953) was the director of the local observatory.
722 Frieda is a bright background asteroid and slow rotator from the inner regions of the asteroid belt. It was discovered by Austrian astronomer Johann Palisa at the Vienna Observatory on 18 October 1911. The stony S-type asteroid has a notably long rotation period of 131.1 hours and measures approximately 9 kilometers in diameter. It was named after Frieda Hillebrand, daughter of Austrian astronomer Karl Hillebrand (1861–1939), and grand-daughter of Edmund Weiss (1837–1917) who had been the director of the discovering observatory.
725 Amanda is a dark background asteroid, approximately 22 kilometers in diameter, that is located in the central regions of the asteroid belt. It was discovered by Austrian astronomer Johann Palisa at the Vienna Observatory on 21 October 1911. The carbonaceous C-type asteroid (CSU/C0) has a short rotation period of 3.7 hours. It was named after Amanda Schorr, wife of German astronomer Richard Schorr (1867–1951).
777 Gutemberga is a dark and large background asteroid, approximately 66 kilometers in diameter, from the outer regions of the asteroid belt. It was discovered by German astronomer Franz Kaiser at the Heidelberg-Königstuhl State Observatory on 24 January 1914. The carbonaceous C-type asteroid (Cb) has a rotation period of 12.8 hours. It was named after Johannes Gutenberg, who introduced the printing press to Europe and started the Printing Revolution.
779 Nina is a large background asteroid, approximately 80 kilometers in diameter, located in the central region of the asteroid belt. It was discovered on 25 January 1914, by Russian astronomer Grigory Neujmin(1886-1946) at the Simeiz Observatory on the Crimean peninsula. The metallic X-type asteroid with an intermediate albedo has a rotation period of 11.2 hours. It was named after the discoverer's sister, Nina Neujmina (Tsentilovich) (1889–1971).
783 Nora is a dark background asteroid from the inner regions of the asteroid belt. It was discovered by Austrian astronomer Johann Palisa at the Vienna Observatory on 18 March 1914. The carbonaceous C-type asteroid has a longer-than average rotation period of 55.5 hours and measures approximately 40 kilometers in diameter. It was likely named after Nora Helmer, principal character in the play A Doll's House by Norwegian poet Henrik Ibsen.
784 Pickeringia is a large background asteroid, approximately 76 kilometers in diameter, located in the outer region of the asteroid belt. It was discovered on 20 March 1914, by American astronomer Joel Hastings Metcalf at the Winchester Observatory in Massachusetts. The dark C-type asteroid has a rotation period of 13.1 hours and an irregular shape. It was named after American astronomers Edward Charles Pickering (1846–1919) and his brother William Henry Pickering (1858–1938).
786 Bredichina is a carbonaceous and very large background asteroid, approximately 104 kilometers in diameter, located in the outer region of the asteroid belt. It was discovered by German astronomer Franz Kaiser at the Heidelberg-Königstuhl State Observatory on 20 April 1914. The elongated C-type asteroid has a longer than average rotation period of 29.4 hours. It was named after Russian astronomer Fyodor Bredikhin (1831–1904).
791 Ani is a very large asteroid of the Meliboea family, located in the outer regions of the asteroid belt. It was discovered on 29 June 1914, by Russian astronomer Grigory Neujmin at the Simeiz Observatory on the Crimean peninsula. The dark carbonaceous C-type asteroid has a rotation period of 11.2 hours and measures approximately 65.7 × 103.5 kilometers, with a mean diameter of 100 km (62 mi). It was named after the historic Armenian city of Ani.
795 Fini is a dark and large background asteroid, approximately 76 kilometers in diameter, located in the central region of the asteroid belt. It was discovered by Austrian astronomer Johann Palisa at the Vienna Observatory on 26 September 1914. The carbonaceous C-type asteroid has a poorly determined rotation period of 9.3 hours and seems rather spherical in shape. Any reference of the asteroid's name to a person is unknown.
803 Picka is a large and dark background asteroid from the outer regions of the asteroid belt. It was discovered on 21 March 1915, by Austrian astronomer Johann Palisa at the Vienna Observatory. The carbonaceous D-type asteroid has a rotation period of 5.1 hours and measures approximately 57 kilometers in diameter. It was named after Czech physician Friedrich Pick (1867–1921).
821 Fanny is a dark background asteroid and slow rotator from the central regions of the asteroid belt. It was discovered on 31 March 1916, by German astronomer Max Wolf at the Heidelberg-Königstuhl State Observatory in southwest Germany. The carbonaceous C-type asteroid (Ch) has an exceptionally long rotation period of 236.6 hours and measures approximately 29 kilometers in diameter. Any reference of the asteroid's name to a person is unknown.
922 Schlutia is a background asteroid from the central regions of the asteroid belt. It was discovered by German astronomer Karl Reinmuth at the Heidelberg Observatory on 18 September 1919. The asteroid with an unknown spectral type has a rotation period of 7.9 hours and measures approximately 18 kilometers in diameter. It was named after Edgar Schlubach and Henry Frederic Tiarks, who sponsored an expedition to observe the solar eclipse of 21 September 1922.
964 Subamara, is a stony background asteroid from the outer regions of the asteroid belt, approximately 20 kilometers in diameter. It was discovered by Austrian astronomer Johann Palisa at the Vienna Observatory on 27 October 1921. The S-type asteroid has a rotation period of 6.9 hours. It was named for the observatory's "very bitter" observing conditions due to light pollution.
977 Philippa is a large background asteroid from the outer regions of the asteroid belt, approximately 65 kilometers in diameter. It was discovered on 6 April 1922, by Russian–French astronomer Benjamin Jekhowsky at the Algiers Observatory in Northern Africa. The C-type asteroid is likely irregular in shape and has a rotation period of 15.4 hours. It was named after French financier Baron Philippe de Rothschild (1902–1988).
1073 Gellivara, provisional designation 1923 OW, is a dark Themistian asteroid, approximately 27 kilometers in diameter, located in the outer regions of the asteroid belt. It was discovered by Austrian astronomer Johann Palisa at the Vienna Observatory on 14 September 1923, and later named after the Swedish town of Gällivare.
1181 Lilith is a metallic asteroid from the middle region of the asteroid belt, approximately 23 kilometers in diameter. It was discovered on 11 February 1927, by Russian–French astronomer Benjamin Jekhowsky at Algiers Observatory in Algeria, Northern Africa, and named after French composer Lili Boulanger.
1280 Baillauda, provisional designation 1933 QB, is a dark background asteroid from the outermost region of the asteroid belt, approximately 52 kilometers in diameter. Discovered by Eugène Delporte at Uccle Observatory in 1933, the asteroid was named after French astronomer Jules Baillaud.
1736 Floirac, provisional designation 1967 RA, is a stony Florian asteroid from the inner regions of the asteroid belt, approximately 8.7 kilometer in diameter.