Phase Curves of Nine Trojan Asteroids over a Wide Range of Phase Angles

Details Phase Curves of Nine Trojan Asteroids over a Wide Range of Phase Angles Phase Curves of Nine Trojan Asteroids over a Wide Range of Phase Angles

2009-12-09

arxiv.org/abs/0912.1888v1

Astronomy and Astrophysics

Astrophysics

Earth and Planetary Astrophysics

Icarus, in press

Scientific paper

We have observed well-sampled phase curves for nine Trojan asteroids in B-, V-, and I-bands. These were constructed from 778 magnitudes taken with the 1.3-m telescope on Cerro Tololo as operated by a service observer for the SMARTS consortium. Over our typical phase range of 0.2-10 deg, we find our phase curves to be adequately described by a linear model, for slopes of 0.04-0.09 mag/deg with average uncertainty less than 0.02 mag/deg. (The one exception, 51378 (2001 AT33), has a formally negative slope of -0.02 +- 0.01 mag/deg.) These slopes are too steep for the opposition surge mechanism to be shadow hiding (SH), so we conclude that the dominant surge mechanism must be coherent backscattering (CB). In a detailed comparison of surface properties (including surge slope, B-R color, and albedo), we find that the Trojans have surface properties similar to the P and C class asteroids prominent in the outer main belt, yet they have significantly different surge properties (at a confidence level of 99.90%). This provides an imperfect argument against the traditional idea that the Trojans were formed around Jupiter's orbit. We also find no overlap in Trojan properties with either the main belt asteroids or with the small icy bodies in the outer Solar System. Importantly, we find that the Trojans are indistinguishable from other small bodies in the outer Solar System that have lost their surface ices (such as the gray Centaurs, gray Scattered Disk Objects, and dead comets). Thus, we find strong support for the idea that the Trojans originally formed as icy bodies in the outer Solar System, were captured into their current orbits during the migration of the gas giant planets, and subsequently lost all their surface ices.

Affiliated with

Also associated with

No associations

Rating

Phase Curves of Nine Trojan Asteroids over a Wide Range of Phase Angles does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Phase Curves of Nine Trojan Asteroids over a Wide Range of Phase Angles, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Phase Curves of Nine Trojan Asteroids over a Wide Range of Phase Angles will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-594102