Open AccessSublimation of Mars's southern seasonal CO 2 ice cap and the formation of spiders
Author(s) -
Piqueux Sylvain,
Byrne Shane,
Richardson Mark I.
Publication year - 2003
Publication title -
journal of geophysical research: planets
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2002je002007
Subject(s) - sublimation (psychology) , mars exploration program , geology , spider , polar , defrosting , impact crater , astrobiology , atmospheric sciences , paleontology , ecology , physics , biology , astronomy , psychology , air conditioning , psychotherapist , thermodynamics
In this paper we define and describe morphological features that have colloquially been termed “spiders” and map their distribution in the south polar region of Mars. We show that these features go through a distinct seasonal evolution, exhibiting dark plumes and associated fan‐shaped deposits during the local defrosting of the seasonal cap. We have documented the seasonal evolution of the cryptic region and have found that spiders only occur within this terrain. These observations are consistent with a geyser‐like model for spider formation. Association with the transparent (cryptic) portion of the seasonal cap is consistent with basal sublimation and the resulting venting of CO 2 gas. Also consistent with such venting is the observation of dark fan‐shaped deposits apparently emanating from spider centers. Spiders are additionally confined to the polar layered deposits presumably due to the poorly consolidated and easily eroded nature of their upper surface.