The Astronomical Society of Greenbelt is an organization made up of people in and around Greenbelt, MD who are interested in astronomy. The group's objective is to educate people about the fascinating science and hobby of astronomy. Persons of all knowledge and skill levels, whether members of the Society or not, are welcome to attend activities.

Up to the start of the pandemic (late March 2020) regular meetings, normally featuring a presentation by an authority on some astronomical topic, were (usually) held on the last non-holiday Thursday of each month at the Greenbelt Community Center.

Star parties were held on selected Saturdays -- and other days for notable events -- at the City of Greenbelt Observatory on Northway (extended) in Greenbelt. Visitors were welcome to set up their own telescopes on the hill there./p>

All of ASG's remaining 2020 scheduled events, including meetings at the Greenbelt Community Center and star parties at the Greenbelt Observatory, were cancelled in late March due to the pandemic. And they remain cancelled. However, we resumed operations in mid-June in an online mode.

Online (Zoom) lectures will be announced here and on our calendar as soon as possible, and in the Greenbelt News Review and by groups.io post (see below) shortly before the event. These events are open to the public, not just to ASG members.

Online (Zoom) star parties likewise will be announced here, and on our calendar, and by groups.io post as soon as practical, using the National Weather Service six-day weather forecast as a guide to scheduling these events. ASG members are operating telescopes in their backyards and screen-sharing the observing experience. The objects observed include solar system planets and deep sky objects such as galaxies, nebulae and star clusters---whatever is currently high enough in the sky to not be blocked by surrounding houses and trees. Attendees are welcome to comment and ask questions. These events too are open to the public, and not just to ASG members. If you would like to be notified by email when a star party is imminent you can write to the ASG Observatory Chair (see Contacts) and request that your email address be added to a list.

Zoom show: "Astronomy Mystery Stories," Thurs. 29 Oct., 7:30 PM: Sue Bassett will present a light-hearted, Halloween-themed talk that includes new evidence on an ancient mystery. All are welcome to join the Zoom session, of any age and whether members of ASG or not. Meet-and-greet starts at 7 PM. See our Events calendar for Zoom connection details.

ASG message server (groups.io/g/greenbeltastro)

2020 ASG brochure (All events will be online until further notice)

2020 ASG star party schedule (All scheduled events have been cancelled until further notice)

"Star Parties at Greenbelt Observatory" (What to expect, when life returns to normality)

"ASG favorite images" (A picture gallery)

News, 17 Mar 2020:  Sebastian Rivera-Muñoz, a student at Eleanor Roosevelt High School in Greenbelt, has completed his senior year Research Project, the development of an image sharpening algorithm now incorporated in ASG's "QuickStack" live-stacking application currently in use at Greenbelt Observatory to enable the observation of very faint cosmological "deep sky objects." Sebastian developed his algorithm, called "2Delta-PSF" (for two times a delta function minus the point spread function), using Microsoft Visual C++, an application development system he mastered (well enough for his purpose) during the course of the project. The beauty of his algorithm is that it uses the telescope-and-camera's image of a star to automatically determine the proper degree of sharpening required, making the process quick and easy to use at ASG star parties. Sebastian compared his algorithm with a standard astronomical image sharpening algorithm called the "Lucy-Richardson deconvolution algorithm," and we deemed his algorithm superior with regard to the aspects important to us (fewer artifacts and acceptable processing time). His mentor for the project was Conrad Terrill of ASG.