The Open UniversitySkip to content
 

The surface roughness of (433) Eros as measured by thermal-infrared beaming

Rozitis, B. (2017). The surface roughness of (433) Eros as measured by thermal-infrared beaming. Monthly Notices of the Royal Astronomical Society, 464(1) pp. 915–923.

Full text available as:
[img]
Preview
PDF (Accepted Manuscript) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Document Language: Unknown
Download (456kB) | Preview
DOI (Digital Object Identifier) Link: https://doi.org/10.1093/mnras/stw2400
Google Scholar: Look up in Google Scholar

Abstract

In planetary science, surface roughness is regarded to be a measure of surface irregularity at small spatial scales, and causes the thermal-infrared beaming effect (i.e. re-radiation of absorbed sunlight back towards to the Sun). Typically, surface roughness exhibits a degeneracy with thermal inertia when thermophysical models are fitted to disc-integrated thermal-infrared observations of asteroids because of this effect. In this work, it is demonstrated how surface roughness can be constrained for near-Earth asteroid (433) Eros (i.e. the target of NASA's NEAR Shoemaker mission) when using the Advanced Thermophysical Model with thermal-infrared observations taken during an ‘almost pole-on’ illumination and viewing geometry. It is found that the surface roughness of (433) Eros is characterized by an rms slope of 38 ± 8° at the 0.5-cm spatial scale associated with its thermal-infrared beaming effect. This is slightly greater than the rms slope of 25 ± 5° implied by the NEAR Shoemaker laser ranging results when extrapolated to this spatial scale, and indicates that other surface shaping processes might operate, in addition to collisions and gravity, at spatial scales under one metre in order to make asteroid surfaces rougher. For other high-obliquity asteroids observed during ‘pole-on’ illumination conditions, the thermal-infrared beaming effect allows surface roughness to be constrained when the sub-solar latitude is greater than 60°, and if the asteroids are observed at phase angles of less than 40°. They will likely exhibit near-Earth asteroid thermal model beaming parameters that are lower than expected for a typical asteroid at all phase angles up to 100°.

Item Type: Journal Item
Copyright Holders: 2016 The Author
ISSN: 1365-2966
Project Funding Details:
Funded Project NameProject IDFunding Body
Probing solar system process using extreme asteroidsNot SetRoyal Astronomical Society (RAS)
Keywords: radiation mechanisms: thermal – methods: numerical – minor planets, asteroids: individual: (433) Eros
Academic Unit/School: Faculty of Science, Technology, Engineering and Mathematics (STEM) > Physical Sciences
Faculty of Science, Technology, Engineering and Mathematics (STEM)
Item ID: 47655
Depositing User: Benjamin Rozitis
Date Deposited: 24 Oct 2016 09:46
Last Modified: 03 May 2019 06:43
URI: http://oro.open.ac.uk/id/eprint/47655
Share this page:

Metrics

Altmetrics from Altmetric

Citations from Dimensions

Download history for this item

These details should be considered as only a guide to the number of downloads performed manually. Algorithmic methods have been applied in an attempt to remove automated downloads from the displayed statistics but no guarantee can be made as to the accuracy of the figures.

Actions (login may be required)

Policies | Disclaimer

© The Open University   contact the OU