A total solar eclipse occurred on June 8, 1918. The eclipse was observed by a U.S. Naval Observatory team at Baker City in Oregon. The painting below shows totality when the Moon prevented the Sun's rays from hitting that part of Oregon. The track of the eclipse was a band across the entire contiguous United States, which would not happen again until 99 years later in 2017. Occurring 3.6 days after perigee, the moon's apparent diameter was larger.
The path
The path of the eclipse started south of Japan, went across the Pacific Ocean, passing northern part of Kitadaitō, Okinawa and the whole Tori-shima in Izu Islands on June 9, and then across the United States and British Bahamas on June 8. The largest city to see totality was Denver, although many could theoretically see it as the size of the shadow was between across as it traveled across America. The longest duration of totality was in the Pacific at a point south of Alaska. The path of the eclipse finished near Bermuda.
U.S. Observation team
The path clipped Washington state, and then moved across the whole of Oregon through the rest of the country, exiting over Florida. The U.S. Naval Observatory obtained a special grant of $3,500 from Congress for a team to observe the eclipse in Baker City, Oregon. The team had been making preparations since the year before, and John C. Hammond led the first members to Baker City on April 11th. The location was important, as it influenced the probability of cloud cover and the duration and angle of the sun during the eclipse. The team included Samuel Alfred Mitchell as its expert on eclipses, and Howard Russell Butler, an artist and physicist. In a time before reliable colour photography, Butler's role was to paint the eclipse at totality after observing it for 112.1 seconds. He noted later that he used a system of taking notes of the colours using skills he had learned for transient effects. Joel Stebbins and Jakob Kunz from the University of Illinois Observatory made the first photoelectric photometric observations of the solar corona from their observing site near Rock Springs, Wyoming
Observation
As the time came for totality the team watched as clouds obscured the sun. The clouds did clear, but during their most important observations the sun was covered by a thin cloud. The sun was completely visible five minutes later. This was not unusual, as cloudy conditions were reported across the country, where the eclipse was also observed from the Yerkes Observatory, Lick Observatory, and Mount Wilson Observatory. Following the 1915 prediction of Albert Einstein's General theory of relativity that light would be deflected when passing near a massive object such as the sun, the USNO expedition attempted to validate Einstein's prediction of light bending by the sun by measuring the position of stars near the sun. However, the cloud cover during totality obscured observations of stars, leaving this test of the validity of general relativity until the solar eclipse of May 29, 1919.
