DPS 34th Meeting, October 2002
Session 8. Inner Planets
Oral, Chair(s): T. Widemann and R.M. Nelson, Monday, October 7, 2002, 4:00-5:00pm, Room M

[Previous] | [Session 8] | [Next]


[8.03] Polarization of the Sodium D-Lines in Mercury's Atmosphere

J. E. Allen, Jr. (NASA/GSFC), M. J. Penn (NSO), B. P. Michael (Catholic Univ. of America and NASA/GSFC), D. Branston (NSO), J. Ceja (Dept. of Physics & Ast., Cal. State-Northridge)

Observations of the linear polarization of the sodium D-lines in the atmosphere of Mercury were made using a polarization analysis package with the Fabry-Perot interferometer at the Dunn Solar Telescope. The spectropolarimetric data resulting from these high-resolution images were subsequently confirmed using a comparable polarization package with the Solar Stellar Spectrograph at the McMath-Pierce Telescope. The observations are analogous to similar measurements of these lines in the Sun’s atmosphere, where they constitute part of the ‘second solar spectrum’. Analysis of the data showed that the D1 line at 589 nm was depolarized, whereas the D2 line at 589.6 nm was polarized at the continuum level, consistent with Hanle-effect depolarization of the ground state and/or J-level quantum interference in the upper state. The discovery of similar behavior in the Hermean sodium D-lines suggests that the second solar spectrum is not unique to the Sun’s atmosphere, but may be more pervasive.

This work supported by NASA and the National Solar Observatory; the latter is operated by the Association of Universities for Research in Astronomy, Inc. under cooperative agreement with the National Science Foundation.


If the author provided an email address or URL for general inquiries, it is as follows:



[Previous] | [Session 8] | [Next]

Bulletin of the American Astronomical Society, 34, #3< br> © 2002. The American Astronomical Soceity.