Spectroscopy and photometry of Mars Trojans

The Hungaria region as a possible source of Trojans and satellites in the inner Solar system

“…The capture of Hungarias as Earth or Martian Trojans is not only due to the migration of planets, but also to migration of asteroids from the Main Belt, this is proved physically by Rivkin et al (2003), who show that two Martian Trojans are collision fragments of a larger body. Numerically, this migration towards the terrestrial planet was described by Galiazzo, Bazsó & Dvorak (2013a), which emphasize the gravitational perturbations.…”

“…Concerning the physical characteristics of the known co-orbital bodies for terrestrial planets, some spectral type of these are known: for the Earth, Cruithne is a Q/S type 9 , YORP is S/V type (from TNEADB); for Mars, 1997 U J7 is an X type, 1998 VF31 is an S type: Rivkin et al (2003) says it is an S(I) type (angrite) and Rivkin et al (2007) suggest also for a S(VII) type (achondrite similar to the spectrum of 40 Harmonia). So Cruithne and 1998 VF31 can again still be considered as possible HCOs, because Hungarias have some S-type asteroids, not the majority, but still 17% (Warner et al 2009) and especially 1997 UJ7 which is an X-type asteroid like the majority of the Hungarias (Carvano et al 2001;Warner et al 2009), even if not specified for the sub-group Xe-type and further spectroscopic analysis would be needed.…”

Albedos and diameters of three Mars Trojan asteroids

“…It is therefore interesting that there is evidence that suggests a diverse history for these bodies. Rivkin et al (2003) obtained visible spectra of the three largest Mars Trojans -(5261) Eureka, (101429) 1998 VF 31 , and (121514) 1999 UJ 7 -and found that Eureka and 1998 VF 31 are likely Sa-or A-class asteroids, whereas 1999 UJ 7 is probably an X-class asteroid. These differing compositions suggest that these asteroids cannot have all formed in the same protostellar disk environment.…”

A dynamical context for the origin of Phobos and Deimos

“…Most of the material presumably re-impacts the surface of Mars on a hyperbolic orbit at some future date, but this scenario may also provide a pathway to emplace objects at the Martian trojan points. The Martian Trojans show spectral features of Olivene that suggest a Martian surface origin (Rivkin et al 2003;Scholl, Marzari & Tricarico 2005;Borisov et al 2017;Polishook et al 2017). Furthermore, the Eureka family of Martian Trojans appears to have an age > 1 Gyr (Scholl et al 2005;Christou 2013;Cuk et al 2015, de la Fuente Marcos & de la Fuente Marcos 2013) which points to a long-lived, possibly almost primordial population.…”