Amateur Astronomers Association of Princeton logo

Image of Messier 27 (NGC 6853) taken by Bob Vanderbei

Enthusiasm for observational astronomy, curiosity about cosmology, achievements with CCD imaging and technology. These and all other aspects of astronomy are interests shared by members of the Amateur Astronomers Association of Princeton. The club is based in Princeton, (Mercer County) New Jersey.

This organization of 100 + promotes astronomy-related activities for members and non-members, novice to expert.  A wide spectrum of astronomy interests are explored at the AAAP through regular meetings, workshops, use of the two club observatories, public outreach and regional star parties.

Come explore our web site.  Here you'll find details about our organization's meetings, discussion topics, members and their scopes, and a lot more. Our organization maintains two observatories: the larger in Washington Crossing State Park (housing a research-grade 355mm Schmidt-Cassegrain catadioptric and historic 159mm Hastings-Byrne refractor). A second facility is found at Jenny Jump State Park in northwestern New Jersey. This houses a 318mm custom-built Newtonian reflector.

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Sidereal Times, our monthly newsletter, is now exclusively digital. Access your copy here.

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The AAAP Invites the Public to the Simpson Observatory, Washington Crossing State Park (NJ side)
Each Friday Evening -- Weather Permitting
Friday evenings, 8:00 PM until 11:00 PM -- clear skies permitting

Come visit the Universe at our state-of-the-art astronomical observatory, located near Pennington, NJ just minutes from I-95. AAAP astronomers will show you galaxies, planets, ghostly nebulae, spectacular globular clusters and jewel-box open star clusters. Using our research-grade Celestron 14" Schmidt-Cassegrain OTA mounted on a Paramount Robotic Mount and historic 6.25" Hasting-Byrne refractor, you'll see the night sky like never before.

** New for 2015! ---> We've installed a Mallincam Astronomical Video Imaging System. View deep sky objects on a large LCD screen.

Click here for current Friday night opening updates (go / no-go).

Click here for observatory description.

Public Lecture: Measuring and Modeling Variability in Quasars and Blazars
September 8, 2015 at 7:30 PM, Peyton Hall, Ivy Lane, Princeton Campus

The first talk of the 2015-2016 season is entitled Measuring and Modeling Variability in Quasars and Blazars by Dr. Paul J. Witta of the Department of Physics of The College of New Jersey.

Dr. Wittas talk will be about active galactic nuclei, including quasars, which are extraordinarily powerful, emitting up to thousands of times as much energy as all the stars in their host galaxies. A minority of them also eject relativistic jets of plasma that form giant radio lobes. All active galactic nuclei are characterized by variability and blazars exhibit the strongest fluctuations. This enhanced variability is due to Doppler boosting of the flux emitted by relativistic jets that point close to our line of sight. We have been measuring variability of quasars and blazars in the optical band from various ground-based telescopes for the past 20 years and have more recently employed the Kepler satellite as well as various X-ray telescopes to gather dense, uniformly spaced data. After setting the context, he will present some of these results, as well as our numerical simulations of variations of radio flux from the turbulent regions behind shocks in the jets.

Dr. Wiita received his PhD in Physics from Princeton in 1976 for producing the first numerical models of radio galaxies. He did post-docs at the Universities of Chicago and Cambridge. He was on the faculty at UPenn and Georgia State University and has been Chair of the Physics Department at TCNJ since 2010. He has been a visiting professor at the Tata Institute for Fundamental Research, the Indian Institute of Astrophysics and Princeton. His research has mostly been in extragalactic astronomy, with a focus on radio loud active galaxies.

Don't miss this exciting presentation describing some of the more cutting edge, dynamic research currently occuring in the astrophysics community.

A members-only, meet-the-speaker dinner will begin at 6:00 PM at Winberie's Restaurant. Members, please RSVP via email to for a reservation.

Peyton Hall is home to the Department of Astrophysical Sciences, and is located just east of Washington Road, adjacent to Palmer Stadium, on the Princeton University campus.


September 11-13, 2015, HOPE CONFERENCE CENTER, HOPE, NJ

This years event will continue the simplifying trend of recent years with a focus on observing and socializing, and with significantly lower costs for attendees.  Bring your own observing equipment or meander between the telescopes of others in the group who will be happy to share their views of the sky with you.  Bill Murray will be creating a Deep Sky Challenge for those desiring to participate.

To be flexible, the event will be walk-in/pay-as-you-go for each night of attendance.  There will be no prepayment and no need to formally pre-register.  However, to communicate with Hope Conference Center our needs for the weekend, we ask that you fill out a non-binding, intention-to-attend form.  Your response will place you on an email list through which all final communication about the event will take place.  Download the form and more infomation here.

The event is open to all AAAP members and their family.  Members may invite select friends who have inquired about our event.  Please send this email to those who want to attend that may not be on our AAAP member email list so they can be informed and respond accordingly.

Accommodations will be mens and womens bunkhouses or you can bring your own tent or RV.  Bathroom and shower facilities are available.  The cost per night is $20 for adults and $10 for children (ages 6-12), regardless of choice of accommodation.

There will be no club prepared meals. The kitchen facilities at the center will be available for our use, however.  There has been discussion of ordering takeout food for the group. Those not inclined to take-out should feel free to band together to visit the local eating establishments or bring their own meals.  Hot and cold drinks and munchies will be available throughout the weekend.

In case of bad or questionable weather, the event will be cancelled. The go/no go decision will be made on the Thursday evening before the event and notification will be made via email.  Please check your email before leaving for the event.

Your intent-to-attend response and any other questions or correspondence should be sent to:


Cookout picnic at the pavilion with fun food and drinks and camaraderie with AAAP members and families.

Silent auction of telescopes, mounts, eyepieces and other astronomy equipment acquired by the club over the past few years.  This is an opportunity to acquire astro equipment at incredibly low prices.
Observing at the AAAP's observatory if skies permit (note: sunset at 6:15 PM)