| Discovery[1] | |
|---|---|
| Discovered by | L. Oterma |
| Discovery site | Turku Obs. |
| Discovery date | 23 March 1939 |
| Designations | |
| (1504) Lappeenranta | |
Named after | Lappeenranta[2] (Finnish city) |
| 1939 FM | |
| main-belt · (inner)[3] background[4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 78.15 yr (28,544 days) |
| Aphelion | 2.7784AU |
| Perihelion | 2.0207 AU |
| 2.3995 AU | |
| Eccentricity | 0.1579 |
| 3.72yr (1,358 days) | |
| 67.942° | |
| 0° 15m 54.72s / day | |
| Inclination | 11.049° |
| 94.866° | |
| 51.074° | |
| Physical characteristics | |
| Dimensions | 11.336±0.149 km[5] 11.931±0.069 km[6] 12.42±0.48 km[7] 12.65 km(derived)[3] 12.70±1.2 km[8] 13.35±2.34 km[9] |
| 8h(dated)[10] 10.44 h[11] 15.16±0.01 h[12] 15.190±0.009 h[a] | |
| 0.1765(derived)[3] 0.1939±0.042[8] 0.1997±0.0312[6] 0.213±0.020[7] 0.270±0.034[5] 0.434±0.184[9] | |
| Tholen =S[1][3] · S[13] B–V = 0.880[1] U–B = 0.418[1] | |
| 10.90[9] · 11.47±0.32[13] · 11.88[1][7][8] · 11.99[3][6][11] | |
1504 Lappeenranta (provisional designation1939 FM) is a stony backgroundasteroid from the inner regions of theasteroid belt, approximately 12 kilometers in diameter. It was discovered on 23 March 1939, by Finnish astronomerLiisi Oterma at theIso-Heikkilä Observatory, and named after the city ofLappeenranta in Finland.[14]
Lappeenranta is a non-family asteroid from the main belt'sbackground population.[4] It orbits the Sun in theinner asteroid belt at a distance of 2.0–2.8 AU once every 3 years and 9 months (1,358 days). Its orbit has aneccentricity of 0.16 and aninclination of 11° with respect to theecliptic.[1] The body'sobservation arc begins four nights prior to its official discovery observation at Turku.[14]
In theTholen classification, Lappeenranta is a commonS-type asteroid.[1]Pan-STARRS photometric survey has also characterized it as an S-type.[13]
Lappeenranta has an ambiguousrotation period. Recent photometric observations gave a period of 15.16 and 15.190 hours with a brightness variation of 0.09 and 0.22magnitude, respectively (U=2/2+),[12][a] whileRichard Binzel obtained a period of 10.44 hours and an amplitude of 0.29 magnitude in the mid-1980s (U=2).[11] An alternative period of 8 hours, which was measured byLaurent Bernasconi and Fernand van den Abbeel (2002) as well as byRené Roy (2006), has been superseded (U=1/1).[10]
According to the surveys carried out by the Infrared Astronomical SatelliteIRAS, the JapaneseAkari satellite and theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer, Lappeenranta measures between 11.336 and 13.35 kilometers in diameter and its surface has analbedo between 0.1939 and 0.434.[5][6][7][8][9]
TheCollaborative Asteroid Lightcurve Link derives an albedo of 0.1765 and a diameter of 12.65 kilometers based on anabsolute magnitude of 11.99.[3]
Thisminor planet was named after the city ofLappeenranta in southeastern Finland. The officialnaming citation was published by theMinor Planet Center on 20 February 1976 (M.P.C. 3928).[2][15]
