BETHLEHEM, Pa. — Brad Klein reviews the week’s astronomical highlights with Bethlehem’s ‘Backyard Astronomy Guy,’ Marty McGuire.
This week, a discussion of the ‘new moon’ which occurs this Thursday night, on Halloween.
In some contexts, the phrase, “new moon” can refer to the first sliver that becomes visible from Earth. This is important in some religious observances, for example.
But the astronomical new moon is the point when the moon is most nearly between the Sun and the Earth.
At that point, the side that faces Earth is in shadow and so invisible to stargazers. And the reason we don’t see it blocking out the stars as it passes overhead is because it rises and sets with the Sun. So it’s still ‘overhead’… in orbit around our planet. But unseen from Earth.
But there are advantages to earthbound stargazers, according to McGuire.
“I love new moon nights or the days surrounding them because you don't have the bright moon washing out the… stars," he said. "The days surrounding a new moon are the best for star gazing.”
So if you are outside, and clouds allow on this Halloween night, take a moment to gaze skyward and enjoy the stars and planets without competition from the moon.