English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

We report on observations of near-Earth asteroid 2011 MD with the SpitzerSpace Telescope. We have spent 19.9 h of observing time with channel 2 (4.5{\mu}m) of the Infrared Array Camera and detected the target within the2{\sigma} positional uncertainty ellipse. Using an asteroid thermophysicalmodel and a model of nongravitational forces acting upon the object weconstrain the physical properties of 2011 MD, based on the measured fluxdensity and available astrometry data. We estimate 2011 MD to be 6 (+4/-2) m indiameter with a geometric albedo of 0.3 (+0.4/-0.2) (uncertainties are1{\sigma}). We find the asteroid's most probable bulk density to be 1.1(+0.7/-0.5) g cm^{-3}, which implies a total mass of (50-350) t and amacroporosity of >=65%, assuming a material bulk density typical ofnon-primitive meteorite materials. A high degree of macroporosity suggests 2011MD to be a rubble-pile asteroid, the rotation of which is more likely to beretrograde than prograde.

Physical Properties of Near-Earth Asteroid 2011 MD