The number of sodium atoms in the region of circumsolar sublimation of interplanetary dust

Sodium emission fromthe zone of circumsolar sublimation of interplanetary dust was searched for during the total solar eclipse of March 29, 2006, using a Fabry-Perot interferometer and interference filter transmitting at 590 nm. The upper limit for the column density sodium atoms is 2 × 108 atoms/cm2, is based on the comparison with the atmospheric sodium emission. This result is compared with the brightness of the zodiacal light and F-corona, as well as the dust density directly measured onboard spacecraft.