(47171) Lempo Trans-Neptunian Object
Discovered on 1 October 1999 by Rubenstein, E. P., Strolger, L.-G. at Kitt Peak.
Lempo is the ancient Finnish devil who, with the help of his two demon cohorts, Hiisi and Paha, brought down the hero Väinämöinen. Within the trans-Neptunian triple system, the satellite (47171) Lempo I was discovered on 2001 Dec. 8 by C. A. Trujillo and M. E. Brown using the Hubble Space Telescope (HST), and is named Paha. The primary was identified as a binary by S. D. Benecchi et al. through re-analysis of the HST data originally obtained by Trujillo and Brown. Lempo refers to the larger component of the central binary and Hiisi to the smaller component.Naming citation (WGSBN Bull. 5, #19, 5), IAU / Minor Planet Center, via NASA/JPL
Where Lempo is today
Seen from above the solar system on 2026-10-14: Lempo is 31.2 au from the Sun and 30.4 au from Earth. Computed from JPL's orbital elements.
Facts
| Number | 47171 |
| Provisional designation | 1999 TC36 |
| Orbit class | Trans-Neptunian Object |
| Rotation period | 6.21 hours |
| Absolute magnitude (H) | 4.94 |
| Orbital period | 250 years |
| Semi-major axis | 39.7 au |
| Perihelion – aphelion | 30.6 – 48.7 au |
| Eccentricity | 0.229 |
| Inclination | 8.40° |
| Closest distance between its orbit and Earth's (MOID) | 29.6 au |
Data: NASA/JPL Small-Body Database and the IAU Minor Planet Center.