 Orbit ofGrotius (blue),inner planets andJupiter (outermost) | |
| Discovery[1] | |
|---|---|
| Discovered by | C. J. van Houten I. van Houten-G. T. Gehrels |
| Discovery site | Palomar Obs. |
| Discovery date | 24 September 1960 |
| Designations | |
| (9994) Grotius | |
| Pronunciation | /ˈɡroʊʃiəs/[2] |
Named after | Hugo Grotius (Dutch jurist)[3] |
| 4028 P-L · 1981 WH9 | |
| main-belt · (middle) Rafita | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 55.59 yr (20,306 days) |
| Aphelion | 3.0391AU |
| Perihelion | 2.1307 AU |
| 2.5849 AU | |
| Eccentricity | 0.1757 |
| 4.16yr (1,518 days) | |
| 204.01° | |
| 0° 14m 13.92s / day | |
| Inclination | 7.1806° |
| 207.15° | |
| 224.33° | |
| Physical characteristics | |
| Dimensions | 3.38 km(calculated)[4] 3.746±0.146 km[5][6] |
| 9.219±0.0067h[7] | |
| 0.20(assumed)[4] 0.263±0.040[5][6] | |
| S[4] | |
| 14.2[5] · 14.273±0.007(R)[7] · 14.3[1] · 14.48±0.45[8] · 14.72[4] | |
9994 Grotius/ˈɡroʊʃiəs/, provisional designation4028 P-L, is a stony Rafitaasteroid from the middle regions of theasteroid belt, approximately 3.5 kilometers in diameter. It was discovered during thePalomar–Leiden survey in 1960, and named after Dutch juristHugo Grotius.
Grotius was discovered on 24 September 1960, by the Dutch astronomersIngrid andCornelis van Houten, on photographic plates taken by Dutch–American astronomerTom Gehrels atPalomar Observatory in California, United States.[9]
Thesurvey designation "P-L" stands forPalomar–Leiden, named after Palomar Observatory andLeiden Observatory, which collaborated on the fruitfulPalomar–Leiden survey in the 1960s. Gehrels used Palomar'sSamuel Oschin telescope (also known as the 48-inch Schmidt Telescope), and shipped thephotographic plates to Ingrid and Cornelis van Houten at Leiden Observatory whereastrometry was carried out. The trio are credited with the discovery of several thousand minor planets.[10]
Grotius orbits the Sun in thecentral main-belt at a distance of 2.1–3.0 AU once every 4 years and 2 months (1,518 days). Its orbit has aneccentricity of 0.18 and aninclination of 7° with respect to theecliptic.[1] The body'sobservation arc begins with its official discovery observation at Palomar.[9]
In August 2010, a rotationallightcurve ofGrotius was obtained from photometric observations in the R-band at thePalomar Transient Factory in California. Lightcurve analysis gave arotation period of 9.2189 hours with a brightness variation of 0.27magnitude (U=2).[7]
According to the survey carried out by theNEOWISE mission of NASA'sWide-field Infrared Survey Explorer,Grotius measures 3.746 kilometers in diameter and its surface has analbedo of 0.263.[5][6] TheCollaborative Asteroid Lightcurve Link assumes a standard albedo forstony asteroids of 0.20 and calculates a diameter of 3.38 kilometers based on anabsolute magnitude of 14.72.[4]
Thisminor planet was named for Dutch juristHugo Grotius (1583–1645), who laid the foundations forinternational law, based onnatural law.[3] He was achild prodigy and enteredLeiden University when he was just eleven years old. The approved naming citation was published by theMinor Planet Center on 11 November 2000 (M.P.C. 41571).[11]
