Observation of the 1970 Mexico solar eclipse.
In the total solar eclipse of March 7, 1970, observation of contact times was made at Puerto Escondido in southern Mexico. The present paper gives the descriptions on the observations and the process of determining the apparent relative position of the sun to the moon. The observation was made by the spectrophotometric method ; the spectrograph was composed of an objective prism of a direct vision type, a telescope (f=930 mm, φ＝58 mm), and a 16 mm-movie camera. Registrations were made at a rate of 16 shots per second for 45 seconds around each contact, and good images of the flash spectra between 4500 A and 5200 A were obtained with precise time recordings. Photographic measurements were carried out at 4615 A on 60 frames for the 2nd contact and 100 for the 3rd. Photographic densities of the spectra were read out referring to the prominent features of the moon’s limb to avoid the effects of image distortions. A curve of the limb darkening of the sun was obtained, which had the maximum gradient of 7.0 m per 1". In order to compare the results of the observation with the limb profiles of Watts' charts, some small modifications were made to both the position angles and the heights in the charts, retaining their datum unmoved. The apparent relative position of the sun to the moon was determined finally on the basis of Watts' charts with the accuracies of 土0.01" in the direction of the apparent relative motion and 土0.1" in its perpendicular. Between the observation results and the ephemeris some differences are found, which are difficult to be explained by the expected corrections to the adopted values of the ephemeris time and the geodetic position of the observation point.
| Main Authors: | , |
|---|---|
| Format: | Journal Contribution biblioteca |
| Language: | Japanese |
| Published: |
1971
|
| Online Access: | http://hdl.handle.net/1834/16349 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|