DPS Pasadena Meeting 2000, 23-27 October 2000
Session 24. Moon and Mercury Posters
Displayed, 1:00pm, Monday - 1:00pm, Friday, Highlighted Tuesday and Thursday, 3:30-6:30pm, C101-C105, C211

[Previous] | [Session 24] | [Next]

[24.06] High-Resolution Spectra of Sodium in Mercury's Atmosphere

J.E. Allen, Jr. (NASA GSFC), M.J. Penn (California State-Northridge), B.P. Michael (NRC/NASA GSFC), D. Branston (NSO-Tucson)

High-resolution (R~100,000) spectral images of the sodium (Na) D1 and D2 lines in Mercury's atmosphere were obtained using a Fabry-Perot interferometer on the Dunn Solar Telescope at Sacramento Peak, NM. Observations were made from May 29 to June 4, 2000 when Mercury was at ~20.5 and 23.2 degrees E elongation with a radial velocity of ~-34.9 and -33.2 km/s, respectively. Preliminary analysis of the data suggests the atmosphere was optically thicker than when these emissions were first observed (Potter and Morgan 1985). This is attributed to the fact that those observations were made close to solar minimum, whereas our measurements were made closer to solar maximum. The observed D1 and D2 emission lines were blue shifted by ~0.74 and 0.71 Å, respectively, corresponding to Doppler shifts of ~-37.65 and -36.29 km/s.

Potter, A. E. and Morgan, T. H. 1985, Science \underline{229}, 651.

[Previous] | [Session 24] | [Next]