1350 Rosselia

1350 Rosselia, provisional designation 1934 TA, is a stony Koronian asteroid from the outer regions of the asteroid belt, approximately 22 kilometers in diameter. Discovered by astronomer Eugène Delporte at the Royal Observatory of Belgium in 1934,^[17] the asteroid was later named after Marie-Thérèse Rossel, editor of the Belgian newspaper Le Soir.^[2]

1350 Rosselia

Shape model of Rosselia from its lightcurve
Discovery[1]
Discovered by	E. Delporte
Discovery site	Uccle Obs.
Discovery date	3 October 1934
Designations
MPC designation	(1350) Rosselia
Named after	Marie-Thérèse Rossel[2] (editor of Le Soir)
Alternative designations	1934 TA · 1926 AF 1929 TN · 1929 VH 1934 VA · 1938 OC 1948 QG · 1949 YY A924 TB
Minor planet category	main-belt · (outer) Koronis[3][4]
Orbital characteristics[1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc	88.09 yr (32,176 days)
Aphelion	3.1133 AU
Perihelion	2.6007 AU
Semi-major axis	2.8570 AU
Eccentricity	0.0897
Orbital period (sidereal)	4.83 yr (1,764 days)
Mean anomaly	65.352°
Mean motion	0° 12m 14.76s / day
Inclination	2.9392°
Longitude of ascending node	139.55°
Argument of perihelion	237.70°
Physical characteristics
Dimensions	20.822±0.185 km[5] 21.083±0.147 km[6] 21.22±0.38 km[7] 22.60±3.16 km[8] 23.35±1.7 km[3][9]
Synodic rotation period	6.0 h[10] 8.1394±0.0002 h[11] 8.140±0.001 h[11][12] 8.14±0.05 h[11] 8.14008±0.00001 h[13] 8.14011±0.00005 h[14] 8.16±0.01 h[15]
Geometric albedo	0.1579±0.025[3][9] 0.185±0.314[8] 0.1960±0.0511[6] 0.199±0.008[7] 0.199±0.022[5]
Spectral type	Tholen = S[1] SMASS = Sa[1] B–V = 0.854[1] U–B = 0.373[1]
Absolute magnitude (H)	10.36±0.25 (R)[15] · 10.67±0.06[16] · 10.68[8] · 10.78[1][3][6][7][9] · 10.81±0.01[12]

Discovery

Rosselia was discovered on 3 October 1934, by Belgian astronomer Eugène Delporte at the Royal Observatory of Belgium in Uccle.^[17] One month later, it was independently discovered by German astronomer Richard Schorr at the Bergedorf Observatory, Hamburg, on 3 November 1934.^[2] The Minor Planet Center only recognizes the first discoverer. The asteroid was first identified as A924 TB at the Simeiz Observatory in October 1924.^[17]

Orbit and classification

Rosselia is a member of the Koronis family (605),^[3][4] a very large asteroid family with nearly co-planar ecliptical orbits in the outer main belt.^[18] It orbits the Sun at a distance of 2.6–3.1 AU once every 4 years and 10 months (1,764 days; semi-major axis of 2.86 AU). Its orbit has an eccentricity of 0.09 and an inclination of 3° with respect to the ecliptic.^[1]

The body's observation arc begins at Lowell Observatory in September 1929, or five years prior to its official discovery observation at Uccle.^[17]

Physical characteristics

In the Tholen classification, Rosselia is a common S-type asteroid.^[1] In the SMASS classification it is an Sa-subtype that transitions to the rare A-type asteroids.^[1]

Rotation period and poles

Several rotational lightcurve of Rosselia have been obtained from photometric observations since 1975.^{[10][11][12][15]} Consolidated lightcurve-analysis gave a well-defined rotation period of 8.140 hours with a brightness amplitude between 0.3 and 0.54 magnitude (U=3).^[3]

Modeling of the asteroid's lightcurve gave two concurring periods of 8.14008 and 8.14011 hours,^[13][14] with two determined spin axis of (67.0°, −64.0°) and (246.0°, −58.0°) in ecliptic coordinates (λ, β).^[13]

Diameter and albedo

According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Rosselia measures between 20.822 and 23.35 kilometers in diameter and its surface has an albedo between 0.1579 and 0.199.^{[5][6][7][8][9]}

The Collaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is, an albedo of 0.1579 and a diameter of 23.35 kilometers based on an absolute magnitude of 10.78.^[3][9]

Naming

This minor planet was named after Marie-Thérèse Rossel (1910–1987), a Belgian businesswoman and editor of the Brussels newspaper Le Soir.^[2] The official naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 122).^[2] Asteroid 1366 Piccolo was also named after an editor of Le Soir by Delporte.