Asteroid Pairs Formed by Rotational Fission
Daniel J. Scheeres
(1)
,
P. Pravec
(2)
,
D. Vokrouhlický
(3)
,
David Polishook
(4)
,
Alan W. Harris
(5)
,
Adrián Galád
(6)
,
Ovidiu Vaduvescu
(7)
,
F. N. Pozo
(7)
,
A. Barr
(7)
,
P. Longa
(7)
,
Frédéric Vachier
(8)
,
François Colas
(8)
,
D. P. Pray
(9)
,
Joseph T. Pollock
(10)
,
Daniel E. Reichart
(11)
,
Kevin M. Ivarsen
(11)
,
Joshua B. Haislip
(11)
,
Aaron P. Lacluyze
(11)
,
P. Kusnirak
(2)
,
T. Henych
(2)
,
Franck Marchis
(12)
,
B. Macomber
(12)
,
S. A. Jacobson
(1)
,
Yurij N. Krugly
(13)
,
A. V. Sergeev
(13)
,
A. Leroy
(14)
1
University of Colorado
2 Astronomical Institute AS CR, Czech Republic
3 Astronomical Institute of Charles University
4 Wise Observatory and Department of Geophysics and Planetary Sciences
5 Space Science Institute, Boulder
6 Comenius University in Bratislava
7 Universidad Catolica del Norte, Chile
8 IMCCE - Institut de Mécanique Céleste et de Calcul des Ephémérides
9 Carbuncle Hill Observatory
10 Appalachian State University
11 University of North Carolina
12 Department of Astronomy, University of California
13 Astronomical Institute of Kharkov National University
14 OMP - Observatoire Midi-Pyrénées
2 Astronomical Institute AS CR, Czech Republic
3 Astronomical Institute of Charles University
4 Wise Observatory and Department of Geophysics and Planetary Sciences
5 Space Science Institute, Boulder
6 Comenius University in Bratislava
7 Universidad Catolica del Norte, Chile
8 IMCCE - Institut de Mécanique Céleste et de Calcul des Ephémérides
9 Carbuncle Hill Observatory
10 Appalachian State University
11 University of North Carolina
12 Department of Astronomy, University of California
13 Astronomical Institute of Kharkov National University
14 OMP - Observatoire Midi-Pyrénées
Résumé
A population of small main-belt asteroid pairs (MBAs) residing on very similar heliocentric orbits have been found and studied recently (Vokrouhlicky and Nesvorny, Astron. J. 136: 280 2008 and Astron. J. 137: 111 2009, Pravec and Vokrouhlicky, Icarus 204: 580 2009). These asteroid pairs show some common properties: they are ubiquitous with pairs found throughout the asteroid population, pair members are separated with low hyperbolic escape velocities (as low as 0.17 m/s), they are young with most pairs probably separated less than 1 Myr ago, and their sizes and mass ratios overlap with the population of orbiting, bound binary systems. Previous investigations of binary asteroids suggests that they were formed from parent bodies spinning at a critical rate by some sort of fission or mass shedding process (Pravec and Harris, Icarus 190: 250 2007, Scheeres, Icarus 189: 370 2007, Walsh et al., Nature 454: 188 2008), however the possibility that these two populations of asteroid pairs and binaries were related was intriguing but lacked of observational data.