Skywatching Events At Sunrise And Sunset On June 21 Will Celebrate The Longest Day Of The Year
Source: UMass News and Media
The public is invited to join University of Massachusetts Amherst astronomers at the standing stones of the UMass Sunwheel on Tuesday, June 21, at 5 a.m. and 7:30 p.m. to observe sunrise and sunset. UMass Amherst astronomers will describe how the Sunwheel works and explain the astronomical cause of the solstice at the roughly hour-long gatherings.
For astronomers, the solstice takes place at the moment when the Sun reaches its northernmost point relative to the stars, which occurs this year at 5:13 a.m. EDT. This marks the astronomical start of summer in the Northern Hemisphere and winter in the Southern Hemisphere.
On the date of the solstice, daylight is longest and nighttime is shortest in the Northern Hemisphere. At local noon in Amherst (about 12:52 pm EDT), the sun will be the highest it gets in the sky all year round, about 71 degrees above the horizon. The Sun passes straight overhead, on this day only, for people living along the Tropic of Cancer.
The Sunwheel’s standing stones mark the changing positions of the Sun and Moon throughout the year, much like ancient calendar-stone sites found around the world. On the date of the June solstice, the Sun rises and sets farthest north at spots along the horizon marked by tall standing stones. Other stones mark the position of the Sun at the equinoxes and winter solstice.
The position where the Sun rises and sets on the horizon changes so gradually around the date of the solstice that it looks as though it is in the same place every day for more than a week. This is the origin of the word solstice, which means “stationary Sun.” Sunwheel visitors who stop in on their own will be able to see the sun rising and setting over the summer solstice stones from roughly June 16 – 26.
The UMass Amherst Sunwheel is located south of McGuirk Alumni Stadium, just off Rocky Hill Road (Amity St.) about one-quarter mile south of University Drive. Visitors to the Sunwheel should be prepared for wet footing and mosquitoes. The events will be canceled in the event of heavy rain. For more info, please visit the Sunwheel website.