| Discovery[1] | |
|---|---|
| Discovered by | E. Bowell |
| Discovery site | Anderson Mesa Stn. |
| Discovery date | 15 May 1985 |
| Designations | |
| (15224) Penttilä | |
Named after | Antti Penttilä[1] (Finnish astronomer) |
| 1985 JG · 1970 HB 2000 HR19 | |
| main-belt[1][2] · (inner) background[3][4] | |
| Orbital characteristics[2] | |
| Epoch 27 April 2019 (JD 2458600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 48.02yr (17,539 d) |
| Aphelion | 3.0019AU |
| Perihelion | 1.8313 AU |
| 2.4166 AU | |
| Eccentricity | 0.2422 |
| 3.76 yr (1,372 d) | |
| 356.13° | |
| 0° 15m 44.64s / day | |
| Inclination | 12.350° |
| 70.116° | |
| 196.23° | |
| Physical characteristics | |
| 7.924±0.119 km[5][6][7] 8.79±3.79 km[8] 9.60±2.05 km[9] | |
| 4.377±0.001 h[10] | |
| 0.04–0.085[5][6][7][8][9] | |
| 13.80[5][7][8] 13.9[1][2][11] 14.13[9] | |
15224 Penttilä (provisional designation1985 JG) is a dark backgroundasteroid from the inner regions of theasteroid belt, approximately 8 kilometers (5 miles) in diameter. It was discovered on 15 May 1985, by American astronomerEdward Bowell at Lowell'sAnderson Mesa Station in Arizona, United States.[1] The likely elongated asteroid has arotation period of 4.4 hours.[11] It was named after planetary scientistAntti Penttilä at the University of Helsinki.[1]
Penttilä is a non-family asteroid from the main belt'sbackground population.[3][4] It orbits the Sun in theinner asteroid belt at a distance of 1.8–3.0 AU once every 3 years and 9 months (1,372 days;semi-major axis of 2.42 AU). Its orbit has aneccentricity of 0.24 and aninclination of 12° with respect to theecliptic.[2]
The body'sobservation arc begins with its first observation, aprecovery taken at theCrimean Astrophysical Observatory in April 1970, or 15 years prior to its official discovery observation atAnderson Mesa Station.[1]
Thisminor planet was named for Finnish postdoctoral researcherAntti Penttilä (born 1977) at theUniversity of Helsinki, an expert on light reflection and absorption on the surface ofsmall Solar System bodies such as asteroids andcometary nuclei, as well as of thecosmic dust released bycometary comae.[1] The officialnaming citation was published on 12 July 2014 (M.P.C. 89081).[12]
The asteroid'sspectral type has not been determined.[3] Due to its lowgeometric albedo, it likely a carbonaceousC-type asteroid(see below).
In June 2015, a rotationallightcurve was obtained for this asteroid fromphotometric observations by astronomer Daniel Klinglesmith at Etscorn Campus Observatory (719), New Mexico. Lightcurve analysis gave arotation period of4.377±0.001 hours with a brightness variation of 0.55 inmagnitude (U=3-), indicative of a non-spherical, elongated shape.[10] Previously, in August 2012, a concurring period of4.3771±0.0064 hours with an amplitude of 0.46 was determined from observations in the R-band by astronomers at thePalomar Transient Factory, California (U=2).[13]
According to the survey carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer, Penttilä measures between 7.9 and 9.6 kilometers in diameter and its surface has analbedo between 0.04 and 0.085.[5][6][7][8][9] TheCollaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20, and hence calculates a smaller diameter of 4.9 kilometers.[11]
