RT @Astroguyz: #OnThisDay 1959: Venus occults Regulus, enabling a study of the planet’s exact diameter & atmosphere: adsabs.harvard.edu/full/1961SvA..…
RT @Astroguyz: #OnThisDay 1959: Venus occults Regulus, enabling a study of the planet’s exact diameter & atmosphere: adsabs.harvard.edu/full/1961SvA..…