Mercury’s Atmosphere: A Surface-Bounded Exosphere

Abstract The existence of a surface-bounded exosphere about Mercury was discovered through the Mariner 10 airglow and occultation experiments. Most of what is currently known or understood about this very tenuous atmosphere, however, comes from ground-based telescopic observations. It is likely that only a subset of the exospheric constituents have been identified, but their variable abundance with location, time, and space weather events demonstrate that Mercury’s exosphere is part of a complex system involving the planet’s surface, magnetosphere, and the surrounding space environment (the solar wind and interplanetary magnetic field). This paper reviews the current hypotheses and supporting observations concerning the processes that form and support the exosphere. The outstanding questions and issues regarding Mercury’s exosphere stem from our current lack of knowledge concerning the surface composition, the magnetic field behavior within the local space environment, and the character of the local space environment.

[1]  A. Milillo,et al.  The contribution of impulsive meteoritic impact vapourization to the Hermean exosphere , 2007 .

[2]  R. Killen,et al.  Burial rate of Mercury's polar volatile deposits , 2005 .

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

[4]  J. Waite,et al.  Atmospheres in the solar system : comparative aeronomy , 2002 .

[5]  Kenneth G. Powell,et al.  Interaction of Mercury with the Solar Wind , 1998 .

[6]  T. Zurbuchen,et al.  Measuring the plasma environment at Mercury: The fast imaging plasma spectrometer , 2002 .

[7]  François Leblanc,et al.  Solar energetic particle event at Mercury , 2003 .

[8]  Pekka Janhunen,et al.  The response of the Hermean magnetosphere to the interplanetary magnetic field , 2004 .

[9]  Grant Heiken,et al.  Book-Review - Lunar Sourcebook - a User's Guide to the Moon , 1991 .

[10]  M. Slade,et al.  Radar Mapping of Mercury: Full-Disk Images and Polar Anomalies , 1992, Science.

[11]  Paul G. Lucey,et al.  Recalibrated Mariner 10 Color Mosaics: Implications for Mercurian Volcanism , 1997, Science.

[12]  D. Hunten,et al.  UPPER LIMIT FOR LITHIUM IN MERCURY'S ATMOSPHERE , 1996 .

[13]  Robert G. Strom,et al.  Exploring Mercury: The Iron Planet , 2003 .

[14]  A. Sprague.  A diffusion source for sodium and potassium in the atmospheres of Mercury and the Moon , 1990 .

[15]  S. Christon.  A comparison of the Mercury and Earth magnetospheres: Electron measurements and substorm time scales , 1987 .

[16]  Thomas E. Moore,et al.  A quantitative model of the planetary Na + contribution to Mercury’s magnetosphere , 2003 .

[17]  N. Ness,et al.  The magnetic field of Mercury, 1 , 1975 .

[18]  D. Hunten,et al.  Diurnal variation of sodium and potassium at Mercury , 2002 .

[19]  R. Killen,et al.  The sodium tail of Mercury , 2002 .

[20]  N. Ness,et al.  Magnetic Field Observations near Mercury: Preliminary Results from Mariner 10 , 1974, Science.

[21]  Mark J. Cintala,et al.  Impact‐induced thermal effects in the lunar and Mercurian regoliths , 1992 .

[22]  F. Raulin,et al.  COMETARY ORGANIC CHEMISTRY: A REVIEW FROM OBSERVATIONS, NUMERICAL AND EXPERIMENTAL SIMULATIONS , 1999 .

[23]  Donald M. Hunten,et al.  Sulfur at Mercury, Elemental at the Poles and Sulfides in the Regolith , 1995 .

[24]  D. Muhleman,et al.  Mercury Radar Imaging: Evidence for Polar Ice , 1992, Science.

[25]  W. Ip,et al.  Mercury’s Birkeland current system , 2002 .

[26]  A. Potter,et al.  Discovery of Sodium in the Atmosphere of Mercury , 1985, Science.

[27]  Thomas A. Bida,et al.  Discovery of calcium in Mercury's atmosphere , 2000, Nature.

[28]  Theodore E. Madey,et al.  THERMAL DESORPTION OF SODIUM ATOMS FROM THIN SiO2 Films , 2000 .

[29]  A. Sprague,et al.  Mercury: Sodium Atmospheric Enhancements, Radar-Bright Spots, and Visible Surface Features , 1998 .

[30]  A. L. Broadfoot,et al.  Mariner 10 - Mercury atmosphere , 1976 .

[31]  J. Eraker,et al.  Electrons and Protons Accelerated in Mercury's Magnetic Field , 1974, Science.

[32]  R. Killen,et al.  Rapid changes in the sodium exosphere of Mercury , 1999 .

[33]  G. Cremonese,et al.  Flux of meteoroid impacts on Mercury , 2005 .

[34]  R. E. Johnson,et al.  Sputtering of sodium on the planet Mercury , 1986, Nature.

[35]  Bernard V. Jackson,et al.  Evidence for space weather at Mercury , 2001 .

[36]  R. Killen,et al.  Spatial distribution of sodium on Mercury , 2006 .

[37]  H. Wiesmann,et al.  Geochronology of high-K aluminous mare basalt clasts from Apollo 14 breccia 14304 , 1987 .

[38]  A. Sprague,et al.  Solar oxygen and calcium in Mercury's exosphere , 2007 .

[39]  W. Ip.  On the surface sputtering effects of magnetospheric charged particles at Mercury , 1993 .

[40]  T. Hill,et al.  A nonsingular model of the open magnetosphere , 1993 .

[41]  R. Killen,et al.  Source rates and ion recycling rates for Na and K in Mercury's atmosphere , 2004 .

[42]  T. Hill,et al.  A Bx-interconnected magnetosphere model for Mercury , 2001 .

[43]  G. Thomas,et al.  Neutral and ion exosphere models for lunar hydrogen and helium , 1974 .

[44]  Shailendra Kumar.  Mercury's atmosphere - A perspective after Mariner 10 , 1976 .

[45]  A. Fitzsimmons,et al.  Sodium D2 line profiles: clues to the temperature structure of Mercury’s exosphere , 1999 .

[46]  A. Sprague.  Mercury's atmospheric bright spots and potassium variations: A possible cause , 1992 .

[47]  M. Mendillo,et al.  Constraints on the origin of the Moon's atmosphere from observations during a lunar eclipse , 1995, Nature.

[48]  C. Russell,et al.  Disturbances in Mercury's magnetosphere: Are the Mariner 10 “substorms” simply driven? , 1998 .

[49]  Martin A. Slade,et al.  Mercury: Full-disk radar images and the detection and stability of ice at the North Pole , 1993 .

[50]  R. Hodges.  Helium and hydrogen in the lunar atmosphere , 1973 .

[51]  A. Potter,et al.  Sodium and potassium atmospheres of Mercury , 1997 .

[52]  François Leblanc,et al.  Mercury's sodium exosphere , 2003 .

[53]  S. Suess,et al.  Mercury: Magnetospheric processes and the atmospheric supply and loss rates , 1981 .

[54]  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 .

[55]  J. Sauvaud,et al.  Centrifugal acceleration of ions near Mercury , 2002 .

[56]  R. Killen.  Crustal diffusion of gases out of Mercury and the Moon , 1989 .

[57]  Larry A. Lebofsky,et al.  Determination of rock type on Mercury and the Moon through remote sensing in the thermal infrared , 1988 .

[58]  S. Krimigis,et al.  Magnetosphere, Exosphere, and Surface of Mercury , 1987 .

[59]  R. Killen,et al.  Spatial distribution of sodium vapor in the atmosphere of Mercury , 1990 .

[60]  F. Aumayr,et al.  Potential sputtering , 2003, Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences.

[61]  W. Ip.  The sodium exosphere and magnetosphere of Mercury , 1986 .

[62]  Pekka Janhunen,et al.  Modelling the solar wind interaction with Mercury by a quasi-neutral hybrid model , 2003 .

[63]  T. H. Morgan,et al.  Potassium in the atmosphere of Mercury , 1986 .

[64]  R. Grard.  Photoemission on the surface of Mercury and related electrical phenomena , 1997 .

[65]  Barry H. Mauk,et al.  The Energetic Particle and Plasma Spectrometer Instrument on the MESSENGER Spacecraft , 2007 .

[66]  R. Killen,et al.  Predicting the long-term solar wind ion-sputtering source at Mercury , 2007 .

[67]  J. W. Chamberlain,et al.  PLANETARY CORONAE AND ATMOSPHERIC EVAPORATION , 1963 .

[68]  Mark R. Lankton,et al.  The Mercury Atmospheric and Surface Composition Spectrometer for the MESSENGER Mission , 2007 .

[69]  David G. Sibeck,et al.  Solar wind control of the magnetopause shape, location, and motion , 1991 .

[70]  L. L. Hood,et al.  Inhibition of solar wind impingement on Mercury by planetary induction currents , 1979 .

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

[72]  David P. Stern,et al.  Modeling the global magnetic field of the large‐scale Birkeland current systems , 1996 .

[73]  A. Potter,et al.  Impact-driven supply of sodium and potassium to the atmosphere of Mercury , 1987 .

[74]  Helmut Lammer,et al.  Mapping of the cusp plasma precipitation on the surface of Mercury , 2003 .

[75]  M. Mendillo,et al.  OBSERVATIONAL TEST FOR THE SOLAR WIND SPUTTERING ORIGIN OF THE MOON'S EXTENDED SODIUM ATMOSPHERE , 1999 .

[76]  T. Berkefeld,et al.  Detection of neutral sodium above Mercury during the transit on 2003 May 7 , 2004 .

[77]  F. Leblanc,et al.  Potential relations between Caloris basin and Mercury's sodium exosphere , 2006 .

[78]  S. Sugita,et al.  Vapor clouds generated by laser ablation and hypervelocity impact , 2002 .

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

[80]  Uwe Fink,et al.  Distribution and Abundance of Sodium in Mercury's Atmosphere, 1985–1988 , 1997 .

[81]  E. Kallio,et al.  Surface conductivity of Mercury provides current closure and may affect magnetospheric symmetry , 2004 .

[82]  A. Potter,et al.  Evidence for Magnetospheric Effects on the Sodium Atmosphere of Mercury , 1990, Science.

[83]  T. H. Morgan,et al.  Ratio of sodium to potassium in the Mercury exosphere , 2002 .

[84]  B. Anderson,et al.  The Magnetometer Instrument on MESSENGER , 2007 .

[85]  James A. Slavin,et al.  The effect of erosion on the solar wind stand-off distance at Mercury , 1979 .

[86]  D. Hunten,et al.  Origin and character of the lunar and mercurian atmospheres , 1997 .

[87]  Kim Strohbehn,et al.  The MESSENGER Gamma-Ray and Neutron Spectrometer , 2007 .

[88]  A. Fujiwara,et al.  Observation of expanding vapor cloud generated by hypervelocity impact , 1996 .

[89]  Clark R. Chapman,et al.  The Geology of Mercury: The View Prior to the MESSENGER Mission , 2007 .

[90]  Johannes Benkhoff,et al.  Mercury's polar caps and the generation of an OH exosphere , 1997 .

[91]  G. Siscoe,et al.  Observations at the planet Mercury by the plasma electron experiment, Mariner 10 , 1976 .

[92]  K. Ogilvie,et al.  Neutral and ion-exospheres in the solar wind with applications to mercury , 1973 .

[93]  Thomas A. Bida,et al.  The calcium exosphere of Mercury , 2005 .

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

[95]  A. Broadfoot,et al.  Interaction of the surfaces of the moon and Mercury with their exospheric atmospheres , 1977 .

[96]  U. Fink,et al.  A new upper limit for an atmosphere of CO2, CO on Mercury , 1974 .

[97]  Pekka Janhunen,et al.  Solar wind and magnetospheric ion impact on Mercury's surface , 2003 .

[98]  A. Potter.  Chemical sputtering could produce sodium vapor and ice on Mercury , 1995 .

[99]  R. Killen,et al.  Space weather at Mercury , 2004 .

[100]  Thomas M. Orlando,et al.  Far-out surface science: radiation-induced surface processes in the solar system , 2002 .

[101]  Richard D. Starr,et al.  The X-Ray Spectrometer on the MESSENGER Spacecraft , 2007 .

[102]  W. Ip,et al.  MHD simulations of the solar wind interaction with Mercury , 2002 .

[103]  G. Siscoe,et al.  Variations in the solar wind stand‐off distance at Mercury , 1975 .

[104]  Manish R. Patel,et al.  The variability of Mercury's exosphere by particle and radiation induced surface release processes , 2003 .

[105]  J. Harmon.  Mercury radar studies and lunar comparisons , 1997 .