The Celestial Sphere

by Matthew Johnson

Summer officially begins on the longest day of the year in our hemisphere. On June 20 at 11:32 p.m. the Earth will have traveled in its elliptical orbit around the sun to the point where we are most directly in line with the sun’s rays. This marks the summer solstice for the northern hemisphere and the winter solstice for the southern hemisphere. On June 20 we will experience 15 hours and 18 minutes of daylight; 6 hours and 13 minutes more daylight than during the short days of December when the sun was late to rise and so early to set. At noon on the summer solstice the sun rises to its maximum point of latitude on the celestial sphere. This position is 23.5 degrees north latitude and is noted as the Tropic of Cancer.

We are fortunate to be on the East Coast on June 10 because those that rise just before the sun will enjoy an annular eclipse of the sun. During an annular eclipse, the new moon’s orbit takes it over the path of the rising sun. Thus, on that Thursday morning, the shadow of the moon created by blocking the sun’s rays will trace a path of partial darkness along parts of the eastern coast of the U.S. The eclipse will be visible in northeastern North America, with Europe witnessing just partial phases.

Do not look directly at the sun when observing the eclipse and do not use optics unless they are properly filtered for observing the sun.

Planets:

June 1: Look to the southeast half an hour before the sun rises to view the moon just below Jupiter, with Saturn to the right of the moon.

June 21: At dusk, the planet Venus will glow brilliantly about 5 degrees below the star Pollux in the constellation Gemini. Mars will be quite faint but glowing a deep russet slightly above and to the left of Pollux.

June 23: For those with a small telescope or binoculars, locate Mars at dusk a bit to the left of its location on the 21st. If one turns their optics to Mars on this date, a myriad of stars will pop into view behind Mars. This is the Beehive cluster in the constellation Cancer, an open cluster of dozens of stars gravitationally bound to one another.

June 27: At dawn, the waning gibbous moon is in the southern sky, with Saturn just above it and Jupiter to the left of this pair.

June 28: At dawn, the moon is wonderfully located between Saturn to the right and Jupiter to the left.

Moon phases:

June 2: Last quarter. 

June 10: New moon. 

June 18: First quarter.

June 24: Full moon. 

June’s full moon is the last full moon of the spring. The Algonquin tribes called this the Strawberry Moon, as wild strawberries were harvested during this short harvest season in the northeastern U.S.