The Chester County Astronomical Society was formed as a non-profit organization dedicated to the education and enjoyment of astronomy for the general public. The Society holds meetings (with member or guest speakers) and observing sessions once a month. Anyone who is interested in astronomy is welcome to attend meetings and become a member of the Society. In addition to the monthly meetings and observing sessions, the Society also provides a variety of services to the public, including astronomy classes as well as telescopes and expertise for "star parties" for school, scout, and other civic groups.

• Saturday, September 7, 2019 - Sidewalk Astronomy in West Chester in partnership with West Chester Parks and Recreation. Setup near the Historic Courthouse at High and Market streets around 7 p.m.
• Tuesday, September 10, 2019 - CCAS Monthly Meeting, Room 113, Merion Science Center (former Boucher Building), West Chester University. The meeting starts immediately after at 7:30 p.m. Guest Speaker: TBA.
• Friday, September 20, 2019 - CCAS Monthly Observing Session, Myrick Conservancy Center, BRC. The observing session starts at sunset.
• Saturday, September 21, 2019 - CCAS Special Observing Session at Nottingham County Park, Nottingham, PA. The observing session is from 8:00 p.m. to 10:00 p.m.
• Saturday, September 28, 2019 - National Astronomy Day. CCAS Special Observing Session at Anson Nixon Park, Kennett Square, PA. The observing session is from 7:30 p.m. to 9:00 p.m.
• Friday, October 4, 2019 - CCAS Monthly Observing Session, Myrick Conservancy Center, BRC. The observing session starts at sunset.
• Saturday, October 5, 2019 - CCAS Special Observing Session at Hoopes Park, West Chester, PA. The free public event starts is 7:00 PM EDT to 9:00 PM EDT. For more information, contact our Observing Chair, Don Knabb.
• Tuesday, October 8, 2019 - CCAS Monthly Meeting, Room 113, Merion Science Center (former Boucher Building), West Chester University. The meeting starts immediately after at 7:30 p.m. Guest Speaker: TBA.
• Saturday, October 19, 2019 - CCAS Special Observing Session, Willistown Conservation Trust Run-a-Muck. The observing session is scheduled for 6:30 – 8:00 p.m. The event is open only to registered participants.

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What's Up for September? In this month's sky, look for lovely crescent Moons at the start and end of the month. The September equinox brings the beginning of fall in the Northern Hemisphere. And Mars is at solar conjunction, meaning it has disappeared from night skies! (When will it return?) Correction: The video states that the Moon will be waning at the beginning of the month and waxing at the end. In fact it is the opposite — the Moon is waxing at the beginning, and waning at the end. We regret the error.

Additional information about topics covered in this episode of What's Up, along with still images from the video, and the video transcript, are available at https://go.nasa.gov/2Hx3bMn.

For star parties and astronomy events near you, visit http://nightsky.jpl.nasa.gov/. Learn about all of NASA's missions at http://www.nasa.gov/.

The society schedules monthly observing sessions in the Myrick Conservation Center of the Brandywine Red Clay Alliance. The observing sessions, which are planned around the new moon, are open to the public and announced in the Society's newsletter, Observations. Owning a telescope or binoculars is not required; anyone interested in observing the heavens is welcome to show up. If you do have a telescope and need help using it, our observing sessions are a great place to practice and learn from other society members.

The Chester County Astronomical Society's regular monthly meetings include a presentation from an invited speaker or the demonstration of an astronomical project by one of the Society's members. After the presentation, a brief business session is held to review the status of society activities. Meetings typically last 1-1/2 to 2 hours including an informal conversation over refreshments before the start of each meeting.

The Society meets at 7:30 PM the second Tuesday of each month in Room MER112 in the Merion Science Center (former Boucher Building) at West Chester University (corner of South Church Street and Rosedale Avenue, West Chester, Pennsylvania). Click for Directions and Maps.

The Chester County Astronomical Society offers "nights out" to interested organizations including local schools, scouting groups, and other civic groups for the purpose of learning more about the heavens. For example, scouting groups often hold them to earn badges for their members. If your organization is interested in hosting a "night out", please contact us.

• Saturday, September 7, 2019 - Sidewalk Astronomy in West Chester in partnership with West Chester Parks and Recreation. Setup near the Historic Courthouse at High and Market streets around 7 p.m.
• Friday, September 20, 2019 - CCAS Monthly Observing Session, Myrick Conservancy Center, BRC. The observing session starts at sunset.
• Saturday, September 21, 2019 - CCAS Special Observing Session at Nottingham County Park, Nottingham, PA. The observing session is from 8:00 p.m. to 10:00 p.m.
• Saturday, September 28, 2019 - National Astronomy Day. CCAS Special Observing Session at Anson Nixon Park, Kennett Square, PA. The observing session is from 7:30 p.m. to 9:00 p.m.
• Friday, October 4, 2019 - CCAS Monthly Observing Session, Myrick Conservancy Center, BRC. The observing session starts at sunset.
• Saturday, October 5, 2019 - CCAS Special Observing Session at Hoopes Park, West Chester, PA. The free public event starts is 7:00 PM EDT to 9:00 PM EDT. For more information, contact our Observing Chair, Don Knabb.
• Saturday, October 19, 2019 - CCAS Special Observing Session, Willistown Conservation Trust Run-a-Muck. The observing session is scheduled for 6:30 – 8:00 p.m. The event is open only to registered participants.

Star parties are national and regional events similar to "nights out" and open to the public. They are held throughout the year. For a list of upcoming national events in 2019, visit the star parties page.

The West Chester University Department of Geology & Astronomy hosts a planetarium show open to the general public on the 2nd Friday of each month. The WCU Planetarium is located in the Schmucker Science Center on Church St. To locate the planetarium, view the campus map.


The shows start promptly at 7:00 P.M. ET and run approximately one hour in length. Late arrivals will not be permitted to enter the planetarium. Each show includes an overview of what is visible in the current night sky and a special focus on some aspect of astronomy.

Reservations are required because the planetarium has limited seating. For contact information, visit the WCU Public Planetarium Shows webpage.