Padua family

The Padua family (FIN: 507), also known as the Lydia family, is a mid-sized family of asteroids of more than a thousand members.

The family is at least 25 million years old. Its members were previously associated to 110 Lydia, and are predominantly X-type asteroids with an albedo of approximately 0.1. Together with the Agnia family, the Padua family is the only other family to have most of its members in a nonlinear secular 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 the outer part of the central asteroid belt having a semi-major axis of approximately 2.75. The family's namesake is the asteroid 363 Padua, while 110 Lydia is now a suspected interloper, despite having the same spectral type.[1][3]:23

Members

Some prominent members with known spectral type.[1]:364 A list of all Paduan aststeroids is given at the "Small Bodies Data Ferret".[4]

Name Type Diameter Albedo Catalog Refs
110 LydiaX860.1808listJPL · MPC · LCDB
363 PaduaX880.057listJPL · MPC · LCDB
1517 BeogradX360.0448listJPL · MPC · LCDB
1766 SlipherC200.057listJPL · MPC · LCDB
2306 BauschingerX210.0526listJPL · MPC · LCDB
2560 SiegmaXc200.057listJPL · MPC · LCDB
3020 NaudtsSl160.057listJPL · MPC · LCDB
3670 NorthcottX190.045listJPL · MPC · —
5087 Emel'yanovX130.057listJPL · MPC · LCDB
5103 DivišX120.074listJPL · MPC · —
8450 EgorovC110.058listJPL · MPC · —
12281 ChaumontX160.032listJPL · MPC · —
Diameter and albedo figures taken from the LCDB, or, if not available, from JPL's SBDB. Also see category.

Lydia former namesake and potential interloper

In previous works (Zappala et al. 1995), this family was named Lydia after 110 Lydia, which is an X-type asteroid in the SMASS 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 an interloper in its "own" family despite its matching spectral type (Carruba 2009; Mothe-Diniz et al. 2005).[1]:369

Also, the asteroid 308 Polyxo was formerly considered the family's largest member.[5] This T-type asteroid is no-longer considered a family member and is categorized as a background asteroid on AstDyS.[4][6]

gollark: I think a useful component of AGI would be being able to efficiently offload subtasks to specialised algorithms instead of just doing them inefficiently in neural networks, but I have no idea if this is very practical or anyone's doing it.
gollark: There are tons of non-learning algorithms which are good for logical reasoning. The fuzzier stuff which humans do easily seems to be what's harder to implement.
gollark: Just encode data in otherwise irrelevant details of the text which tokenisers remove/ignore.
gollark: It should randomly use a generated goose or actual goose and see how often people can tell the difference.
gollark: Someone should make the command more efficient by checking the goose's direction for you, automatically.

References
  1. Carruba, V. (May 2009). "The (not so) peculiar case of the Padua family". Monthly Notices of the Royal Astronomical Society. 395 (1): 358–377. Bibcode:2009MNRAS.395..358C. doi:10.1111/j.1365-2966.2009.14523.x.
  2. Carruba, V.; Domingos, R. C.; Nesvorný, D.; Roig, F.; Huaman, M. E.; Souami, D. (August 2013). "A multidomain approach to asteroid families' identification". Monthly Notices of the Royal Astronomical Society. 433 (3): 2075–2096. arXiv:1305.4847. Bibcode:2013MNRAS.433.2075C. doi:10.1093/mnras/stt884.
  3. Nesvorný, D.; Broz, M.; Carruba, V. (December 2014). Identification and Dynamical Properties of Asteroid Families. Asteroids IV. pp. 297–321. arXiv:1502.01628. Bibcode:2015aste.book..297N. doi:10.2458/azu_uapress_9780816532131-ch016. ISBN 9780816532131.
  4. "Small Bodies Data Ferret". Nesvorny HCM Asteroid Families V3.0. Archived from the original on 16 August 2017. Retrieved 22 July 2017.
  5. Ridpath, Ian (2003). Oxford Dictionary of Astronomy. Oxford University Press. ISBN 0199609055. Retrieved 25 January 2016.
  6. "AstDyS-2 data for (308) Polyxo". AstDyS – Asteroids Dynamic Site. Retrieved 30 August 2017.
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