We moved last month from 181st to 160th Street. Besides unpacking boxes, I’ve been scouting new observing locations. This little plaza at 155 St and Riverside looked perfect: lots of foot traffic, plenty of sidewalk space, and a wonderfully clear view of the sky from south-east to west.
Everything came together last night with a clear sky, a first quarter Moon well-positioned just after sunset, and lots of passersby eager to observe. It doesn’t get much better than this in Manhattan!
The Moon, Jupiter, Saturn: these are the showstoppers, bright, vivid, and dramatic. Then there are what amateur astronomers call the faint fuzzies. These are dim, indistinct, and subtle. Yet they can be the most astonishing objects you might observe in a backyard telescope.
The scene was First Encounter Beach in Eastham, on Cape Cod. After the sun set, I turned my telescopes to the Moon and then Saturn as it rose later. Dozens of people stopped to look as they left the beach; some stayed for an hour or more.
Things got really exciting when another astronomer arrived with a huge, 15″ telescope.
Telescopes are often described by the width of their aperture, or opening. The larger the aperture, the more light it gathers and the “deeper” you can see. That is, you can see fainter objects. And you can resolve more detail in any object, bright or faint. My own telescopes are 4″ and 7″ in aperture and well-suited to my primarily urban observing.
A 15″ telescope is what we call a light bucket: it scoops up light and excels at showing off the faint fuzzies. And it’s a creature of dark skies, like here on the Outer Cape.
I’m sorry to admit that I didn’t get a photo of the big telescope (I’m still kicking myself). It attracted a lot of attention! You needed to climb a step ladder to view through it. Observers were treated to views of distant galaxies, (collections of billions of stars orbiting an immense black hole, like our own Milky Way galaxy), wispy nebulae (glowing gas and dust, the remnants of exploded stars or stellar nurseries where new stars are forming), and sparkling globular clusters (tightly-packed clusters of stars that reside within our galaxy). Many of these faint fuzzies are impossible to see in my telescope. Others appear extremely faint, requiring averted vision and a lot of imagination.
Beside the cosmic scale and grandeur of these objects, the distances involved are great. The Moon is about 220,000 miles away, or just over one light-second. Saturn averages 800 million miles distance, or about 80 light-minutes. People at the beach were amazed to learn that some of the faint fuzzies are millions of light-years away; the light they were seeing began its journey to Earth while our pre-human hominid ancestors were learning to walk upright and make tools.
Thank you to Matt for hauling his 100+ pound telescope to First Encounter, and to everyone who stopped to look and talk.
