From the Director

Rex

by Rex Parker, PhD

Return to Peyton Hall! After completing HVAC renovations and moving the entire Astrophysics Department back into Peyton Hall, Princeton University has graciously accepted our request to return to the Peyton Hall Auditorium for the new season. Beginning with our September 8 program we will convene again at 7:30pm in Peyton. Please see Ira’s column for information about the speaker presentation.

At the Sept. 8 meeting. we’ll also discuss plans for the two events items described below. I hope that you’ll take advantage of the astronomical delicacies that we’re serving up.

Upcoming AAAP Events

  • Jersey StarQuest, Sept 11/12. Here’s a redesign of the Star Party concept – to make it easier to participate with a focus on hands-on observational astronomy. Even if you don’t own a telescope, here’s your chance!
    • Walkin registration, no advance payment, no pre-registration needed. You can decide to attend at the last minute. We do ask that you send in a non-binding intent-to-participate form, if possible, so we can estimate needs for the Hope Conference Center. Download the form and more information here.
    • AAAP member event, a chance to make friends in the club. You’re also welcome to invite family and friends who may not yet be members.
    • Reduced prices: the cost per night is $20 for adults and $10 for children (ages 6-12), regardless of choice of bunkhouse or tent/RV camping.
    • No meals will be provided by the club. You should bring your own food and plates etc. The center’s kitchen will be available, and we may self-organize for carry-out food from local establishments. Hot and cold drinks will be available throughout the weekend.
  • Star Picnic and Astro Equipment Auction, Oct 18. (Oct 25 rain date). Start at 3:00pm at the pavilion next to the Nature Center at Washington Crossing State Park. Featuring:
    • 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 which AAAP has acquired in recent years. Since we have limited storage space these items definitely must go — this can be an opportunity to acquire astro equipment at incredibly low prices. More details will be provided next month.
    • Observing session will be held that evening at the nearby observatory if skies permit (note, sunset at 6:15pm).

 Celestron-14 Telescope Test – Results. Several members gathered on Aug 26 at WC Observatory for telescope and mount enhancement work. The Hastings 6.25-inch refractor was temporarily dismounted and the new C14 was placed onto the second Paramount-ME. This allowed unbiased, direct side-by side optical performance comparison of the newer and older C14’s on identical Paramounts.

First, Bill Murray and I adjusted collimation of both telescopes using the defocused diffraction pattern of a 3rd magnitude star to precisely center the secondary mirrors; collimation was equivalent for the two scopes. Star diagonals were removed and nearly identical 31 and 34 mm 2-inch eyepieces were directly inserted. The nine gathered members then observed three selected objects back-to-back through the two scopes and voted on performance after each object.

The test objects were Saturn; M-11 (the rich, “wild duck” open star cluster); and the double star Izar (Epsilon Boötis, mag 2.4 and 5.1, 3 arc-sec). Results were unequivocal: 7 of 8 members consistently favored the newer C14 images for all three objects (one observer did not vote). To my eye, the difference was surprisingly apparent. The newer telescope provided sharper, pinpoint stellar images, and Saturn’s ring division was more detectable. The double star showed baseline resolution in the newer but not the older C14.

The next step will be to organize a work party to swap out the older C14 with the newer one on the original Paramount. We plan to sell the older C14. Thanks to Bill, Dave, Jen, John, Gene, Arshad, Ira, and Michael for helping make this a convincing optical test.

This entry was posted in September 2015, Sidereal Times and tagged , , , , . Bookmark the permalink.

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