Planetary Lunch Seminar – Dan Lalich (Cornell)

Title: Bright Radar Reflections Below the Martian South Polar Cap: Wet or Dry?

Abstract: The South Polar Layered Deposit of Mars (SPLD) is a kilometers-thick formation of relatively pure water ice that takes its name from the ubiquitous layering visible in both optical imagery and radar sounding data. Recently, radar observations collected by the MARSIS radar on board Mars Express have revealed strong reflections at the base of the deposit that were initially interpreted as evidence for liquid water. Lakes and other hydrological features are common beneath ice sheets on Earth, but until now there had been no evidence of subglacial liquid water on present day Mars. While such a possibility is exciting, recent studies have questioned the feasibility of that interpretation. In this talk I will present the evidence both for and against a wet-based SPLD, and describe multiple alternate interpretations for those bright reflections.

About this Series: The MIT Planetary Lunch Seminar [PLS] is a weekly seminar series organized within the EAPS department. Colloquia topics span the range of research interests of the department’s planetary sciences research program. The seminars take place on Tuesdays from 12:30–1:30 pm, unless otherwise noted (term-time only). Speakers include members of the MIT community and visitors. Talks are intended to appeal to graduate students, postdocs, research scientists, and faculty with a background in planetary science. Contact: planetary-org@mit.edu.