Astronomical Society

of Long Island


NOTICE:  All content on this site is Copyright ©2016 by Ken Spencer, The Astronomical Society of Long Island, and the respective photographers.  All Rights Reserved.  Reproduction is forbidden without express written permission.


Aug 2 - Learning to See - by Ken Spencer.  “Seeing is in some respect, an art which must be learnt.  Many a night I have been practicing to see, and it would be strange if one did not acquire a certain dexterity by such constant practice.”   -- William Herschel   When we look at objects in our telescope for the first time, we most likely will not see all the detail that is visible.  The first time we see Jupiter, we are aware of the disk of Jupiter, with some kind of faint bands on the surface, and perhaps the tiny spots of light that are the four visible moons.  As we study Jupiter over time, and read more about the planet, we learn that there are four belts, which are sometimes very subtle, and when we go back to the eyepiece, sure enough, we can see more of the bands if we look carefully.  This is "seeing" in the astronomical sense and it can be learned.  This talk will cover both observing the planets, and deep sky objects as well.  We will learn some descriptive terms as well - words that will help us to look more carefully.

Aug 9 - Space Mission Mishaps - by John Speroni: There’s a good reason why “it isn’t rocket science” is a saying: mission success requires the complex coordination of physics, chemistry, biology, mathematics, technology, and human factors. There are high consequences of failure with explosive fuel, extreme speeds, hostile environments, and vast distances making many errors unrecoverable. John will talk about selected mishaps from 1930 through more recent times. .

Aug 16 - Observing Night - Weather Permitting. We will only observe if the skies are clear. Bring your own telescope or binoculars, or come and observe through our instruments. New Moon is August 20th. Please do not park on the lawn

TOTAL SOLAR ECLIPSE AUGUST 21 - But totality is not visible on Long Island, sad to say.

Aug 23 - 2nd Observing night. During the warm weather months, we have been scheduling two observing nights a month, in hopes that we will actually get to observe. Do not park on the lawn

Aug 30 - To Be Announced

Messier 27 - The Dumbbell Nebula

This is a magnificent image of The Dumbell Nebula done recently by ASLI member Jonathan Nelson.  This object was the first planetary nebula to be discovered; by Charles Messier in 1764. At its brightness of visual magnitude 7.5 and its diameter of about 8 arc minutes, it is easily visible in binoculars, and a popular observing target in amateur telescopes.  However, in amateur instruments it only appears as a black and white image because of the inability of the human eye to see color in very low brightness.  Doing long exposure astrophotography like this is a very demanding process.  The total time of all exposures exceeds one hour and thirty minutes!  Here are the technical details:

Scope: Explore Scientific 102ED Triplet Essentials Series

Mount: Celestron AVX

Guiding: Orion Magnificent Mini AutoGuider Package

Camera: Canon Rebel T5

Other: Explore Scientific Field Flattener and Orion SkyGlow Imaging Filter

Capturing Software: BackyardEOS (with dithering), PHD2

Processing: Entirely in Pixinsight 1.8

Light Frames: 19 x 180" (57 min total)

Dark Frames: 10 x 180"

NGC 4216 in the Virgo Cluster by Dave Barnett

Our intrepid astrophotographer Dave Barnett apparently needs no sleep at all, judging by his latest handiwork.  In the center of the frame is the galaxy NGC 4216 in the Virgo Cluster.  It is 40 million light-years distant, and is an edge-on spiral galaxy.  It is nearly 100,000 light-years across, about the size of our own Milky Way galaxy.  It is flanked by fellow Virgo cluster member NGC 4222.  If you are thinking of trying astrophotography, you should know this is not a simple trick.  He used an 8” f/4 Newtonian, and this final image is a stack of 4 minute long sub exposures with a total time of 92 minutes.