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Autumnal Equinox

Do you know what the Autumn Equinox is all about?

Autumnal Equinox Twice a year Earth undergoes a celestial alignment called an equinox. There are another two similar events called solstice which occur in June and December. The equinox alignments occur in September, the Autumnal Equinox and spring, the Vernal Equinox. In just a few days, Wednesday, September 22, 2016 ...
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Upcoming Events

Star Parties and Club Meetings

ChesMont Astronomical Society

Join us at the Crow’s Nest Preserve for our monthly club meeting. We will have a special guest speaker, John Conrad, who will speak about “Looking Deep and Deeper (Hubble, JWST, WFIRST)”

DATE: Sunday, November 13, 2016
TIME: 7:00 am - 9:00 am EDT
WHERE: Crows Nest Preserve
201 Piersol Road Elverson, PA 19520

Bucks-Mont Astronomical Association

General Meeting. Featured presentation: Deep sky imaging and sharing your deep sky images.

DATE: Wednesday, November 2, 2016
TIME: 7:30 PM
WHERE: Upper Dublin Lutheran Church
411 Susquehanna Road, Ambler, PA 19002.

DVAA Public Star Party

At a star party, one can look through many different types and sizes of telescopes, and see astronomical wonders most people have never seen.

DATE: Saturday, November 5, 2016
TIME: 6:00 pm
WHERE: Model airplane field
Valley Forge National Historic Park.


About 90 Millimeter Observatory

About 90 Millimeter Observatory

90 Millimeter Observatory seeks to introduce students, parents and educators to STEM education through astronomy using the tools of amateur astronomy such as readily available telescopes at public star parties. We also seek opportunities to present astronomy focused classroom presentations followed by Solar observing and offing astronomy presentations and observing opportunities to students and parents during evening and after school programs. In addition, 90 Millimeter Observatory seeks to hold public star parties during township events held at public locations like parks, township buildings and public libraries.

We believe that 90 Millimeter Observatory has the potential to serve the public as well as educators at the middle and high school levels to introduce science through astronomy and encourage students to pursue careers in science, technology, engineering and math (STEM) and encourage parents and educators to support those efforts.

About Our Founder

Dan Acker has been an amateur astronomer and an avid deep sky observer since 1978 and is a member of the Delaware Valley Amateur Astronomers, Bucks-Mont Astronomical Association and founder of the 90 Millimeter Observatory. In 1986 he co-founded the ChesMont Astronomical Society. Dan welcomes your comments at


Contact us with your questions about astronomy, telescope or observing.