_Flammario.png) Shape model ofFlammario from itslightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | M. F. Wolf |
| Discovery site | Heidelberg Obs. |
| Discovery date | 11 March 1924 |
| Designations | |
| (1021) Flammario | |
Named after | Camille Flammarion[2] (French astronomer) |
| 1924 RG · 1977 UM A910 CE | |
| main-belt[1][3] · (outer)[4] background[5] | |
| Orbital characteristics[3] | |
| Epoch 23 March 2018 (JD 2458200.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 92.70yr (33,857 d) |
| Aphelion | 3.5188AU |
| Perihelion | 1.9556 AU |
| 2.7372 AU | |
| Eccentricity | 0.2855 |
| 4.53 yr (1,654 d) | |
| 10.840° | |
| 0° 13m 3.36s / day | |
| Inclination | 15.869° |
| 115.44° | |
| 286.97° | |
| Physical characteristics | |
| 84.78±22.26 km[6] 97.38±1.23 km[7] 97.96±34.85 km[8] 98.015±8.377 km[9] 99.39±2.3 km[10] 99.6±19.9 km[11] 100.765±1.608 km[12][3][13] 105±11 km[14] | |
| Mass | (8.6 ± 3.87/2.84)×1017 kg[13] |
Meandensity | 1.606 ± 0.722/0.529 g/cm3[13] |
| 12.146±0.001 h[15] 12.146 h[16][17] 12.15186±0.00005 h[18] 12.160±0.002 h[19] 12.16 h[19] | |
| 0.04±0.01[14] 0.04±0.06[8] 0.045±0.006[12][3] 0.0458±0.002[10] 0.0470±0.0200[9] 0.048±0.001[7] 0.05±0.02[6][11] | |
| Tholen =F[3] · F[20] SMASS =B[3][4] B–V = 0.656[3] U–B = 0.230[3] | |
| 9.06[3]8.98 [4][7][6][9][10][11][14] 9.03[8] 9.34±0.27[21] | |
1021 Flammario, provisional designation1924 RG, is a dark backgroundasteroid from the central regions of theasteroid belt, approximately 100 kilometers (62 miles) in diameter. It was discovered on 11 March 1924, by German astronomerMax Wolf at theHeidelberg-Königstuhl State Observatory in Heidelberg, Germany.[1] The asteroid was named after French astronomerCamille Flammarion.[2] AnF-type asteroid, it has arotation period of 12.16 hours.[4]
Flammario is a non-family asteroid from the main belt'sbackground population.[5] It orbits the Sun in thecentral asteroid belt at a distance of 2.0–3.5 AU once every 4 years and 6 months (1,654 days;semi-major axis of 2.74 AU). Its orbit has aneccentricity of 0.29 and aninclination of 16° with respect to theecliptic.[3]
The asteroid was first observed asA910 CE at Taunton Observatory (803) in February 1910. The body'sobservation arc begins at thePulkovo Observatory near Saint Petersburg, Russia, in January 1928, more than four years after its official discovery observation at Heidelberg.[1]
In theSMASS classification,Flammario is a "bright" carbonaceousB-type, while it is an uncommonF-type asteroid in theTholen taxonomy. (The SMASS taxonomic scheme classifies all F-types as B-type asteroids).[3][4] More recentpolarimetric observations also characterized the asteroid as a dark F-type.[20]
Several rotationallightcurves ofFlammario have been obtained fromphotometric observations since the 1990s (U=2/2/2).[15][16][17] Analysis of the best-rated lightcurve obtained by French amateur astronomerLaurent Bernasconi in January 2005 gave arotation period of 12.160 hours with a consolidated brightness amplitude between 0.14 and 0.40magnitude (U=3-).[4][19]
In 2016, a modeled lightcurve using photometric data from various sources, rendered a similar sidereal period of 12.15186 hours and twospin axes of (32.0°, 22.0°) and (216.0°, 55.0°) inecliptic coordinates.[18]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Flammario measures between 84.78 and 105 kilometers in diameter and its surface has a lowalbedo between 0.04 and 0.05.[6][7][8][9][10][11][12][14]
TheCollaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is, an albedo of 0.0458 and a diameter of 99.39 kilometers based on anabsolute magnitude of 8.98.[4]
Fienga et al. estimated the mass ofFlammario as (8.6 ± 3.87/2.84)×1017 kg, with a theoretical bulk density of 1.606 ± 0.722/0.529 g/cm3.[13]Small Solar System bodies may have 20% of more porosity (which decreases with the size of the body due to self-gravity). The carbonaceous outer-belt asteroids typically show a higher macroporosity than the basaltic, stony asteroids from the inner regions of the asteroid belt.[22]
Thisminor planet was named after renowned French astronomerCamille Flammarion (1842–1925), who founded the French Astronomical Society (French:Société astronomique de France) and the astronomical journalL'Astronomie in the 1880s. The official naming citation was mentioned inThe Names of the Minor Planets byPaul Herget in 1955 (H 98). The lunar craterFlammarion as well as the craterFlammarion on Mars were also named in his honor.[2]
