3 Vul is found to be a single-lined spectroscopic binary with a period of 367 days, very nearly equal to one year. Velocity observations over two decades, in combination with archival data, have produced sufficiently good phase coverage to yield a well-defined orbit. Nonetheless, residuals from a Keplerian velocity curve are larger than expected for the sharp-lined B6 III primary: Night-to-night and possibly more rapid non-Keplerian radial-velocity variations occur. High-resolution observations of Si II lines reveal marked line-profile changes during single and successive nights. Preliminary evidence suggests that low-amplitude photometric variations may be present also. It is suggested that the primary is a member of the nonradially pulsating "53 Persei" class of variable stars.
Observed timings of 244 sunrises and 135 sunsets from two closely spaced geographic locations in Edmonton, Alberta, were used to determine astronomical refraction for the Sun's upper limb. The observed astronomical refraction had a mean of 0Њ .669, a standard deviation of 0Њ .175, and a range between 0Њ .402 and 2Њ .081. At sunrise, the astronomical refraction had a mean of 0Њ .714, a standard deviation of 0Њ .184, and a range between 0Њ .402 and 2Њ .081. At sunset, the astronomical refraction had a mean of 0Њ .579, a standard deviation of 0Њ .108, and a range between 0Њ .442 and 1Њ .085. There is a strong annual variation of the monthly mean and the monthly standard deviation of the astronomical refraction. Both parameters reach a maximum during the coldest months for sunrises and sunsets. Abnormally large refraction events-sometimes called Novaya Zemlya solar mirages-can occur in both warm and cold months.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.