Marking More Risings and Settings

We can give our planetarium the same information that Dr. Hawkins gave his computer. Right now the stars, Sun, Moon, (and planets, if you are using them) are positioned as they would be on today’s date, about 3500 years ago, about the time when the giant trilithons were erected. The first stages of Stonehenge were built much earlier, 4800 years ago, in 2800 BC. While the stars change their rising and setting positions substantially, the Sun and Moon positions change only a little.
And here we have four of the major, repeated alignments as determined by Hawkins.

DIGITAL EFFECT: Stonehenge Panorama and Trilithons
Fade on the symbolic Stonehenge panorama and trilithons, as viewed from the center of Stonehenge. The trilithon images should be placed so that the planetarium’s Sun will rise and set in these openings on the solstices at the latitude of Stonehenge, 51 degrees north. (The solstices are the longest and shortest days of the year, usually June 21 and December 21, although variations in our calendar with respect to the actual motion of the Earth around the Sun vary the actual dates by a day or so from year to year.) The panorama with the smaller stones should be placed in between the trilithons. Place the panorama and trilithon images individually (four times for each image) so that they match to your dome. It may be necessary to stretch the smaller stones to fit inbetween, and to stretch the aspect ratio of the trilithons for better viewing.

DIGITAL EFFECT: Suntrail On
If possible, fade on the sun trail. The audience should note that the path does not coincide with any of the four alignments.

Do any of these alignments match the sunrise and sunset we marked earlier? [No.]Leave those markers in place.

Fade Off Panorama, Trilithons, and Suntrail

At this point, Professor Hawkins made some more guesses, hypotheses, about what astronomical events might be marked by these special directions, and then tested them on his computer. We are going to do precisely the same thing here in the planetarium. We are going to experience a night at Stonehenge, about 3500 years ago. I can speed up the rotation of the Earth, and make the night seem to go by in about three minutes.

You can each decide to mark the risings or settings of bright stars, planets, Sun, Moon, star groups, or whatever else you happen to see on the horizon where you are standing.

DIGITAL EFFECT: Mark Overnight
Crossfade the scene to approximately one hour past sunset on -1500/10/31, with the clock and cardinal directions on.

We are ready to begin. Remember what object you marked when you finish, and leave your marker in place when you sit down.

DIGITAL EFFECT: Go to Sunrise… Slowly move forward to approximately one hour before sunrise on -1500/11/01 in two minutes. This gives the audience time to mark the position of the rising or setting of an object of their choice. 
Fade in music. 
As you go through the night, ask what objects students are tracking. Some students will be watching bright stars in the north, such as the Big Dipper. When their stars fail to set, and start going up again, point out the existence of these “circumpolar” stars, stars which never go below the horizon.

DIGITAL EFFECT: Go to Morning
Run diurnal motion to mid-morning.
Fade out music.

Good morning! We have lots of risings and settings marked, and now we can see which, if any, agree with the directions marked by Stonehenge.

DIGITAL EFFECT: Stonehenge Panorama and Trilithons
Fade on the symbolic Stonehenge panorama and trilithons, as viewed from the center of Stonehenge, to check the audience’s selection of rising or setting targets. Ask several students to describe what they marked, how it moved through the sky, and to point out their markers.

DIGITAL EFFECT: Go to Evening
Turn down atmosphere and the Sun.

Have we solved the mystery of Stonehenge?

As you might imagine, Professor Hawkins was also disappointed when his computer gave him this same result. There were one or two stars which agreed with one or two alignments, but that could have been just coincidence. To succeed, he needed something to work consistently with all his alignments.

Fade off the Stonehenge Panorama and Trilithons.