Relative Humidity on Mars: New Results From the Phoenix TECP Sensor

We present our recalibration of Phoenix's humidity sensor. This recalibration was conducted with a copy of the sensor subjected to the environmental conditions at the Phoenix landing site. Our experiments focus on the warmest and driest conditions because they were not covered in previous calib...

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Bibliographic Details
Published in:Journal of Geophysical Research: Planets
Main Authors: Fischer, Erik, Martínez, Germán M., Rennó, Nilton O., Tamppari, L. K., Zent, A. P., orcid:0000-0001-5885-236X
Format: Article in Journal/Newspaper
Language:English
Published: AGU 2019
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Online Access:https://hdl.handle.net/20.500.11753/1480
https://doi.org/10.1029/2019JE006080
Description
Summary:We present our recalibration of Phoenix's humidity sensor. This recalibration was conducted with a copy of the sensor subjected to the environmental conditions at the Phoenix landing site. Our experiments focus on the warmest and driest conditions because they were not covered in previous calibrations. Our recalibration shows daytime water content values one order of magnitude larger than those in the previous calibration. At nighttime conditions, our results are in excellent agreement with the previous calibration. Our higher daytime values are in better agreement with independent estimates from the ground, and from orbit. Our results imply larger diurnal variations of water content at Phoenix compared to Curiosity, suggesting a stronger atmosphere‐soil interchange in the Martian arctic than at lower latitudes. Further, they indicate that environmental conditions favorable for the formation of saline solutions (brine) are only achieved temporarily between midnight and 6 a.m. on a few Martian days. E. Fischer, G. M. Martínez, N. O. Rennó, L. K. Tamppari, A. P. Zent