Sunspot intensity observations during the 9 May 1970 Mercury transit

Observations of stray-light and sunspot

Observations of stray-light and sunspot intensities during the Mercury transit of 1970 May 9

✍ W. Mattig 📂 Article 📅 1971 🏛 Springer 🌐 English ⚖ 428 KB

In order to test the usual method for correcting sunspot intensity measurements for stray light, we have measured, during the Mercury transit of 1970 May 9, the intensities of Mercury, a sunspot umbra, and the aureole. The direct observations result in Mercury intensities < 0.06 10 and aureole inten