Starry Heavens Newsletter
June 2017

---

Upcoming Micromoon
Occurs June 9, 2017. A micromoon occurs when a full moon or a new moon coincides with apogee; the point in the moon’s orbit farthest away from Earth. The moon orbits the earth in an elliptical path thus one side of the path is closer to Earth, and the other side of the path is farthest away. The point in the Moon’s orbit closest to Earth is called perigee, and the point in the orbit farthest from Earth is called apogee. A full or new moon that occurs at apogee is called a micromoon, minimoon or apogee moon. A full moon or new moon that occurs around perigee is called supermoon. TheSupermoonon November 14, 2016, was the closest a Full Moon has been to Earth since January 26, 1948. The next time a Full Moon will be closer to Earth will be on November 25, 2034 (dates based on UTC time). Because a Micromoon is farther away, it looks approximately 14% smaller than a Supermoon. In addition, the illuminated area appears 30% smaller, so it will look a little less bright.

 
https://www.timeanddate.com/astronomy/moon/lunar-perigee-apogee.html

The Moon passes through the 2 extreme points (perigee and apogee) in its orbit about once a month.The time it takes for the Moon to travel from perigee to perigee, is called the anomalistic month, and takes around 27.55455 days. This is not to be confused with the synodic month, which lasts a little longer, and is the time it takes the Moon to orbit once around Earth, from New Moon through all the moon phases to the next New Moon.
 
We know that the moon has an affect on high and low tides and the greatest difference between high and low tide is around the full moon and new moon. These tides are known as spring tides. At these times the gravitational forces of the moon and the sun combine to pull the ocean’s water in the same direction. If a spring tide occurs at perigee (or perihelion - when the sun is closest to the earth) the tide is called a Perigean spring tide or, more colloquially, a "King Tide". Perigean spring tides are 5cm or 2 inches higher in variation than regular spring tides. 
                              ***********************
Time again to celebrate The Summer Solstice
The Summer Solstice is considered to be the longest day of the year because it is when the earth experiences the most daylight, that is, in the northern hemisphere. In the southern hemisphere it is the shortest day of the year. How so? Because of the tilt of Earth’s rotational axis. The date occurs when Earth’s axis tilts towards the sun, June 20 and June 22 in the northern hemisphere.

From the winter solstice, which occurs around Dec. 20, daylight increases by approximately one minute each day until January 7, when we add approximately two minutes of daylight (one at sunrise and one at sunset as sunrise is one minute earlier per day and sunset one minute later each day) until the summer solstice. Of course the opposite is true in the southern hemisphere. This year in Hawaii, the summer solstice occurs June 20, at 18:25 hours (6:25pm HST).
 
http://earthsky.org/earth/gallery-the-summer-solstice-as-seen-from-stonehenge

The summer and winter solstices have been celebrated throughout the world for centuries. Ancient architectural markers of the solstice such as Stonehenge stand to this day.  It is thought that the structures at Stonehenge plotted the Sun’s movement around the horizon and informed times for planting and harvesting and other ancient rituals. In modern times crowds gather at Stonehenge facing in a northeasterly direction to watch the sun rise over the heel stone and simply revel and celebrate the beginning of summer.                                                                                 
     

• $7 General admission
• $6 WCC students, military, seniors (65 years or older), with ID
• $5 Children (ages 4-12 years)
• Free for children under 4 years of age (1 per paying adult), and WCC faculty or staff with university ID

---

---