ThePadua family (FIN:507), also known as theLydia family, is a mid-sizedfamily of asteroids of more than a thousand members.
The family is at least 25 million years old. Its members were previously associated to110 Lydia, and are predominantlyX-type asteroids with analbedo of approximately 0.1. Together with theAgnia family, the Padua family is the only other family to have most of its members in anonlinearsecular resonance configuration, with more than 75% of its members in a z1 librating state.[1][2][3]: 23
The Paduan (Lydian) asteroids are located in theouter part of the central asteroid belt having asemi-major axis of approximately 2.75. The family's namesake is the asteroid363 Padua, while 110 Lydia is now a suspectedinterloper, despite having the same spectral type.[1][3]: 23
Some prominent members with known spectral type.[1]: 364 A list of all Paduan asteroids is given at the "Small Bodies Data Ferret".[4]
| Name | Type | Diameter | Albedo | Catalog | Refs |
|---|---|---|---|---|---|
| 110 Lydia | X | 86 | 0.1808 | list | JPL · MPC · LCDB |
| 363 Padua | X | 88 | 0.057 | list | JPL · MPC · LCDB |
| 1517 Beograd | X | 36 | 0.0448 | list | JPL · MPC · LCDB |
| 1766 Slipher | C | 20 | 0.057 | list | JPL · MPC · LCDB |
| 2306 Bauschinger | X | 21 | 0.0526 | list | JPL · MPC · LCDB |
| 2560 Siegma | Xc | 20 | 0.057 | list | JPL · MPC · LCDB |
| 3020 Naudts | Sl | 16 | 0.057 | list | JPL · MPC · LCDB |
| 3670 Northcott | X | 19 | 0.045 | list | JPL · MPC · — |
| 5087 Emelʹyanov | X | 13 | 0.057 | list | JPL · MPC · LCDB |
| 5103 Diviš | X | 12 | 0.074 | list | JPL · MPC · — |
| 8450 Egorov | C | 11 | 0.058 | list | JPL · MPC · — |
| 12281 Chaumont | X | 16 | 0.032 | list | JPL · MPC · — |
| Diameter and albedo figures taken from the LCDB, or, if not available, from JPL's SBDB. Also seecategory. | |||||
In previous works (Zappala et al. 1995), this family was named Lydia after110 Lydia, which is anX-type asteroid in theSMASS classification (Tholen:M-type). While Lydia is still a member of the now-called Padua family (Nesvorny 2005, AstDyS), it has been suspected that it might be aninterloper in its "own" family despite its matching spectral type (Carruba 2009; Mothe-Diniz et al. 2005).[1]: 369
Also, the asteroid308 Polyxo was formerly considered the family's largest member.[5] ThisT-type asteroid is no longer considered a family member and is categorized as a background asteroid on AstDyS.[4][6]