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 Plus annual

Presents the access of premium content as premium feature

Premium Content

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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

133P/Elst-Pizarro is the firstly recognized main-belt comet, but we stillknow little about its nucleus. Firstly we use mid-infrared data ofSpitzer-MIPS, Spitzer-IRS and WISE to estimate its effective diameter $D_{\rmeff}=3.9^{+0.4}_{-0.3}$ km, geometric albedo $p_{\rm v}=0.074\pm0.013$ and meanBond albedo $A_{\rm eff,B}=0.024\pm0.004$. The albedo is used to compute 133P'stemperature distribution, which shows significant seasonal variation,especially polar regions, ranging from $\sim40$ to $\sim200$ K. Based oncurrent activity observations, the maximum water gas production rate isestimated to be $\sim1.4\times10^{23}\rm~s^{-1}$, being far weaker than$\sim10^{26}\rm~s^{-1}$ of JFC 67P at similar helio-centric distance $\sim2.7$AU, indicating a thick dust mantle on the surface to lower down the gasproduction rate. The diameter of the sublimation area may be $<\sim200$ maccording to our model prediction. We thus propose that 133P's activity is morelikely to be caused by sublimation of regional near-surface ice patch ratherthan homogeneous buried ice layer. Such small near-surface ice patch might beexposed by one impact event, before which 133P may be an extinct comet (orice-rich asteroid) with ice layer buried below $\sim$40 m depth. The proposedice patch may be located somewhere within latitude $-50\sim50^\circ$ bycomparing theoretical variation of sublimation temperature to the constraintsfrom observations. The time scale to form such a thick dust mantle is estimatedto be $>100$ Myr, indicating that 133P may be more likely to be a relativelyold planetesimals or a member of an old family than a recently formed fragmentof some young family.

Low activity main belt comet 133P/Elst-Pizarro: New constraints on its Albedo, Temperature and Active Mechanism from a thermophysical perspective