What is the summer solstice? How is it linked to the seasons, the famous Stonehenge monument, and the Strawberry Moon?
When the full moon for the month of June happens to occur on the summer solstice, the phenomenon is known as the “Strawberry Moon”. The nickname isn’t linked to the color, however, but instead is believed to originate from the Algonquin tribes that used the full moon of June as an indicator that it was time to start picking strawberries and other fruit. The last Strawberry Moon was nearly 70 years ago.
The Science of Stonehenge
The famous human-arranged rock formation known as Stonehenge was built over a span of time between 3,000 and 1,600 B.C. and offers proof of how culturally significant the Sun was, as well as what careful solar observers our ancestors must have been.
The formation of around 100 massive, upright stones laid out carefully in circles continues to fascinate in part because many of the details of how and why it was built are still not understood. While the sandstone rocks that form the outer portion of the monument are similar to those found in nearby quarries, some of the stones that make up the inner ring had to have been transported somehow from 200 miles away. Historians further believe it was once a burial ground, but are not sure what other purposes it may have served. One of those purposes was clearly astronomical.
Standing inside the rock formation provides a view of the Sun rising perfectly through an entrance formed by a rough rock known as the heel stone.
The monument draws huge crowds on the summer solstice because on the longest day of the year, standing inside the rock formation provides a view of the Sun rising perfectly through an entrance formed by a rough rock known as the heel stone. The alignment between stone and rising Sun has remained accurate despite thousands of years of the Earth’s slight precession.
Stonehenge is also connected to the winter solstice. On the shortest day of the year in the northern hemisphere (on or around December 20th), the Sun rises in line with three vertical stones that support a similarly large horizontal stone, a formation known as the Trilithon.
The monument continues to draw visitors but most are no longer allowed to walk among or touch the stones due to problems with erosion. Exceptions are given to those with religious connections to the site, including Neo-Druids, pagans, and some other Earth-based religions.
Since we have reached the summer solstice here in the northern hemisphere, the days will only grow shorter from now on. So soak up that sun while you can!
Until next time, this is Sabrina Stierwalt with Ask Science’s Quick and Dirty Tips for helping you make sense of science. You can become a fan of Ask Science on Facebook or follow me on Twitter, where I’m @QDTeinstein. If you have a question that you’d like to see on a future episode, send me an email at firstname.lastname@example.org.