AMHERST, Mass. – The public is invited to witness the summer solstice sunrise and sunset among the standing stones of the UMass Amherst Sunwheel on Wednesday, June 21 at 5 a.m. and 7:30 p.m. This Sunwheel event marks the astronomical change of season when days are longest and nights are shortest in the Northern hemisphere. Heavy rain cancels the events.
At the hour-long gatherings, UMass Amherst astronomy professor Stephen Schneider will discuss the astronomical cause of the sun’s solstice or standstill. This refers to the fact that the sun appears to rise at a fixed spot on the northeast horizon and to set in a fixed northwest direction for more than a week, as marked by the tallest stones in the Sunwheel.
The exact moment of the solstice is 12:24 a.m. EDT on June 21, marking the time when the sun reaches farthest north in its relationship to the earth. There is very little change in the sun’s position for about 10 days around this date, so visitors to the Sunwheel can see the sun rising and setting over the tall summer solstice standing stones from about June 16 to 26.
Visitors will hear a presentation on the seasonal positions of Earth, the sun and moon, the upcoming solar eclipse on August 21, building the Sunwheel and other calendar sites such as Stonehenge in England and Chankillo in Peru. Schneider will also answer other astronomical questions.
If it is clear during the morning session, a telescope will be set up to observe the crescent moon and Venus. During the evening session a solar telescope will be available to safely observe the surface of the sun. About an hour after sunset there also may be an opportunity to view Jupiter and Saturn through a telescope.
The UMass Amherst Sunwheel is located south of McGuirk Alumni Stadium, just off Rocky Hill Road (Amity Street) about one-quarter mile south of University Drive. Visitors to the Sunwheel should be prepared for wet footing and mosquitoes. Donations to help with the cost of additional site work and future events are greatly appreciated.