High‐Resolution, Ground‐Based Observations of the Lunar Sodium Exosphere During the Lunar Atmosphere and Dust Environment Explorer (LADEE) Mission

We present the first comprehensive set of lunar exospheric line width and line width derived effective temperatures as a function of lunar phase (66° waxing phase to 79° waning phase). Data were collected between November 2013 and May 2014 during six observing runs at the National Solar Observatory McMath‐Pierce Solar Telescope by applying high‐resolution Fabry‐Perot spectroscopy (R ~ 180,000) to observe emission from exospheric sodium (5,889.9509 Å, D2 line). The 3‐arc min field of view of the instrument, corresponding to ~336 km at the mean lunar distance (384,400 km), was positioned at several locations off the lunar limb; only equatorial observations taken out to 950 km are presented here. We find the sodium effective temperature distribution to be approximately a symmetric function of lunar phase with respect to full Moon. Within magnetotail passage we find temperatures in the range of 2500–9000 K. For phase angles greater than 40° we find that temperatures flatten out to ~1700 K.

[1]  M. Horányi,et al.  Constraining the Ratio of Micrometeoroids From Short‐ and Long‐Period Comets at 1 AU From LADEE Observations of the Lunar Dust Cloud , 2018 .

[2]  M. Horányi,et al.  Meteoritic influence on sodium and potassium abundance in the lunar exosphere measured by LADEE , 2016 .

[3]  A. Colaprete,et al.  How surface composition and meteoroid impacts mediate sodium and potassium in the lunar exosphere , 2016, Science.

[4]  Paul R. Mahaffy,et al.  Detections of lunar exospheric ions by the LADEE neutral mass spectrometer , 2015 .

[5]  E. Grün,et al.  A permanent, asymmetric dust cloud around the Moon , 2015, Nature.

[6]  P. S. Athiray,et al.  C1XS results-First measurement of enhanced sodium on the lunar surface , 2014 .

[7]  M. Fujimoto,et al.  Structure of the ionized lunar sodium and potassium exosphere: Dawn‐dusk asymmetry , 2014 .

[8]  V. Tenishev,et al.  Kinetic modeling of sodium in the lunar exosphere , 2013 .

[9]  C. Schmidt Monte Carlo modeling of north‐south asymmetries in Mercury's sodium exosphere , 2013 .

[10]  SarantosM. The lunar sodium atmosphere: April–May 19981 1This article is part of a Special Issue that honours the work of Dr. Donald M. Hunten FRSC who passed away in December 2010 after a very illustrious career. , 2012 .

[11]  F. Roesler,et al.  Sodium Atoms in the Lunar Exotail: Observed Velocity and Spatial Distributions , 2012, 1204.0762.

[12]  M. Taguchi,et al.  Variation in lunar sodium exosphere measured from lunar orbiter SELENE (Kaguya) , 2010 .

[13]  A. Sharma,et al.  Sources of sodium in the lunar exosphere: Modeling using ground-based observations of sodium emission and spacecraft data of the plasma , 2010 .

[14]  F. Roesler,et al.  High‐resolution spectroscopy of the lunar sodium exosphere , 2009 .

[15]  N. Mouawad,et al.  EXPECTED EMISSION FROM MERCURY'S EXOSPHERIC SPECIES, AND THEIR ULTRAVIOLET–VISIBLE SIGNATURES , 2009 .

[16]  A. Sharma,et al.  Influence of plasma ions on source rates for the lunar exosphere during passage through the Earth's magnetosphere , 2008 .

[17]  U. Rohner,et al.  The lunar exosphere: The sputtering contribution , 2007 .

[18]  Andrew F. Cheng,et al.  Mercury’s Atmosphere: A Surface-Bounded Exosphere , 2007 .

[19]  H. Spence,et al.  Magnetospheric influence on the Moon's exosphere , 2006 .

[20]  T. Madey,et al.  Photon-stimulated desorption of Na from a lunar sample: temperature-dependent effects , 2004 .

[21]  G. Cremonese,et al.  The 1999 Quadrantids and the lunar Na atmosphere , 2001, astro-ph/0106447.

[22]  R. Killen,et al.  Variation of lunar sodium during passage of the Moon through the Earth's magnetotail , 2000 .

[23]  S. Alan Stern,et al.  The lunar atmosphere: History, status, current problems, and context , 1999 .

[24]  T. Madey,et al.  Photon-stimulated desorption as a substantial source of sodium in the lunar atmosphere , 1999, Nature.

[25]  Steven Smith,et al.  Discovery of the distant lunar sodium tail and its enhancement following the Leonid Meteor Shower of 1998 , 1999 .

[26]  Cesare Barbieri,et al.  Possible detection of meteor stream effects on the lunar sodium atmosphere , 1998 .

[27]  T. H. Morgan,et al.  Coronagraphic observations of the lunar sodium exosphere near the lunar surface , 1998 .

[28]  Theodore E. Madey,et al.  Desorption of alkali atoms and ions from oxide surfaces: Relevance to origins of Na and K in atmospheres of Mercury and the Moon , 1998 .

[29]  D. Hunten,et al.  Observations of Sodium in the Lunar Atmosphere during International Lunar Atmosphere Week, 1995 , 1998 .

[30]  R. J. Reynolds,et al.  Fabry-Perot CCD annular-summing spectroscopy: study and implementation for aeronomy applications. , 1996, Applied Optics.

[31]  W. Smyth,et al.  The Sodium and Potassium Atmospheres of the Moon , 1995 .

[32]  W. Feldman,et al.  Variation of lunar sodium emission intensity with phase angle (Paper 94GL01702) 2263 , 1994 .

[33]  Jeffrey Baumgardner,et al.  Imaging experiments to detect an extended sodium atmosphere on the moon , 1993 .

[34]  D. Hunten,et al.  The sodium and potassium atmosphere of the moon and its interaction with the surface , 1992 .

[35]  A. Potter,et al.  Observations of the lunar sodium exosphere , 1991 .

[36]  W. Ip The atomic sodium exosphere/coma of the Moon , 1991 .

[37]  T. H. Morgan,et al.  Limits to the lunar atmosphere , 1991 .

[38]  A. Potter,et al.  Extended sodium exosphere of the Moon , 1988 .

[39]  D. Hunten,et al.  Observations of sodium in the tenuous lunar atmosphere , 1988 .

[40]  A. Potter,et al.  Discovery of Sodium and Potassium Vapor in the Atmosphere of the Moon , 1988, Science.

[41]  A. Potter,et al.  Lunar luminescence and the filling‐in of Fraunhofer lines in moonlight , 1984 .

[42]  R. Hartle Model for Rotating and Nonuniform Planetary Exospheres , 1971 .

[43]  D. McNutt,et al.  Telluric absorption, residual intensities, and shifts in the Fraunhofer D lines , 1963 .

[44]  E. Grün,et al.  A permanent , asymmetric dust cloud around the , 2019 .

[45]  M. Sarantos,et al.  Improved Velocity Distributions for Exospheric Na and K Surrounding the Moon , 2017 .

[46]  Marko Wagner,et al.  Theory Of Planetary Atmospheres , 2016 .

[47]  J. Emery,et al.  Modeling the Moon's extended sodium cloud as a tool for investigating sources of transient atmospheres , 1997 .