April 2011

April 2011 Meeting Notes

This month's business meeting included discussion of the upcoming St. John School Star Night, plans for Astronomy Day in May, interest in having a booth at Sunfest in June, and a request for a volunteer to coordinate on-line social media for the club. Following the business meeting, Joyce Gray-Ritchie summarized some of the more interesting recent astronomical news, and Duane Perkins showed a new sky darkness meter. Daryl Doughty presented the program, "DSLR Astrophotography".

Business Meeting

St. John School Star Night

On the evening of Monday, April 11, BAS will provide "Star Night" for the 5th, 6th, 7th and 8th grade students of St. John School. Joyce Gray-Ritchie has worked hard to coordinate the event with St. John science teacher, Colleen Bennet and principal Jane Sears. In order to avoid rescheduling problems, which have caused considerable difficulty in the past, this will be a fixed date. If weather does not allow us to set up telescopes outside, we will be prepared to provide an interesting indoor astronomical program. Good weather or bad, the event will begin with a short introductory orientation in the school gym, to establish a few basic concepts and ground rules for the kids. In addition to Joyce's introduction, a member of the club will give a brief demonstration of how to use a telescope, so that the students will understand what to do and what not to do.

Many years ago the Bartlesville Astronomical Society purchased a large, inflatable portable planetarium and donated it to the Bartlesville Public Schools. Joyce persuaded BPS to allow us to use it at St. John's for this event, so there will be one or two planetarium shows. In case of bad weather, Daryl Doughty has offered to give a presentation that he did for the BPS "Pinwheels and Popcorn" summer program last year. We also hope to have several scopes set up in the gym, and perhaps a laptop with planetarium program, attached to a video projector. Even if the weather is bad, we'd still like to have all volunteers present to help with the indoor program. Those with smart phones, PDA's or tablet computers with astronomy software are encouraged to bring them and use them during Star Night. The kids will relate easily to these devices. If you haven't volunteered yet, please contact Joyce Gray-Ritchie or John Grismore. An email with additional details will be sent to volunteers later this week. Thanks.

Astronomy Day

This year National Astronomy Day is Saturday, May 7. It's been many years since the club has provided any public activities for Astronomy Day, so we hope to make a concerted effort this year. The two events under consideration have been some form of static, daytime display in a heavily trafficked public location, and an evening star viewing. Since the most appropriate place for a daytime display would probably be the Washington Park Mall, Steve Plank checked with the administration there about allowing BAS to set up in the Mall on May 7. Unfortunately, the Mall requires a $250 fee, even for non-profit, educational organizations such as ours. Since this is currently beyond our means, and since a brief discussion did not reveal any other good alternatives, the idea of a daytime display has been dropped. This will allow us to focus our Astronomy Day efforts on an evening star viewing. Our club has previously established a relationship with the Bartlesville Parks and Recreation Department, and we have permission to have such public activities in any city public park. They merely request that we inform them ahead of time, and offer in return to advertise our event on the Parks and Recreation Facebook page. Last fall we had a small, public star party in Sooner Park, just southeast of the Sooner Pool parking lot. Despite lights from the nearby schools, the site worked well, and will be the location for our Astronomy Day Star Viewing. We'll try to publicize this event extensively, so we'll need as many volunteers as we can get. Mark your calendars now.

SunFest

Steve also investigated Bartlesville's Sunfest as an opportunity for the club to make itself more visible. BAS had a booth at Sunfest for a few years, many years ago, and it was a very high traffic event with lots of contact with the public. A show of hands determined that there was strong support among members to have a booth at Sunfest this year, so we will begin planning for the event. The application form and $30 registration fee will be submitted within the next couple of weeks. Since Sunfest is a three day event, lasting from June 3 through June 5, we will need all the volunteer support we can get, to keep the booth continuously occupied. We hope to have a couple of scopes on display, a folding table or two with handouts and demonstration materials, and perhaps a laptop to demonstrate specific concepts with a planetarium program, or provide other astronomical materials. Ideally, if someone in the club has a scope with a good solar filter, we'd like to use a video camera and LCD display to provide a continuous, live image of the sun during Sunfest. There are a few challenges to overcome. Sunfest does not provide electricity, and will not allow generators, so all our equipment will have to run on batteries. In addition, we will need some kind of cover or canopy to shade volunteers. And finally, if possible, it would be very helpful to have a closed trailer or vehicle to quickly load our equipment into, in case of stormy weather, but we don't yet know if Sunfest will allow this.

BAS Social Media

Last year, during a discussion about increasing the club's visibility, Mike Woods suggested that we consider creating a Facebook page for the club. Now might be a good time to extend the club's reach, not just through Facebook, but also through other social media, such as Twitter. What we need is a volunteer to coordinate the development and ongoing updates of our on-line social media presence. During a brief discussion of what is needed, several of the more senior members, or perhaps I should say "legacy members", suggested that the right person "should be young, and should know what they're doing", but we've yet to reject any volunteer due to age. Come to think of it, we've never rejected any volunteer for any reason. :-) Volunteers will be taken on a first come, first serve basis, so don't delay. Contact John Grismore.

What's News - Joyce Gray-Ritchie

After the business meeting, Joyce reported on several recent astronomical news items. Of particular interest were a couple of unusual supernovae discoveries. The first was a gamma ray burst that preceded an extraordinarily bright supernova, peeking at nearly one trillion! times brighter than the Sun. The extraordinarily intense release of energy in a very short period of time didn't fit the light curve of a typical supernova. Further investigation has suggested that the observation was actually of an entire star violently torn apart and completely swallowed by a supermassive black hole at the center of a galaxy over 4 billion light years (24,000,000,000,000,000,000,000 miles) away.

The second supernova article discussed a new theoretical study of "failed" supernovae. These enigmatic objects have been theorized for some time to occur when extremely massive stars undergo the core collapse that leads to the brilliant supernovae explosions seen in galaxies millions or even billions of light years away. But in a "failed" supernova, the star is so massive that its core collapse leads to the formation of a black hole so massive that all the photons created in the energy burst cannot escape, and are immediately swallowed up. From a distance, the star appears to simply collapse and completely disappear. For that reason it has been assumed that such events could never be detected, since no light escapes. But the new theoretical study suggests that it might be possible to detect neutrinos escaping from the collapse, holding the promise of some day detecting these extraordinary events.

Daryl Doughty reported that there will be a quadruple conjunction of Jupiter, Venus, Mars and Mercury in early May. The grouping will be at its most compact around May 10 and will appear low in the eastern sky about 45 minutes before sunrise. This should be a unique observing opportunity if you have an eastern view clear nearly to the horizon.

Duane Perkins showed a new sky darkness meter. Simply pointing it toward the sky and pressing a button results in an LED display of the overall "sky brightness" magnitude number, for the small region of sky it is pointing it. We look forward to using this at the St. John Star Night.

DSLR Astrophotography

Speaker - Daryl Doughty

In this month's program, Daryl Doughty explained the basic characteristics and procedures of DSLR astrophotography. Beginning with a clear, yet detailed discussion of digital single lens reflex cameras, he explained the optics, sensor technology, pixel count, resolution and memory requirements of modern DSLR cameras. When selecting an appropriate camera for astrophotography, there are inevitable trade-offs between resolution, storage, weight and sensitivity. Additional important factors include spectral response of the sensor, programmability, computer interfacing and software support. For a variety of reasons, including extensive software for image downloading and processing, and extensive camera programmability and computer control, about 80% of DSLR astrophotography is done with Canon cameras.

With his own personal examples, Daryl demonstrated that DSLR cameras are very flexible for a wide variety of astrophotographic applications, including lunar, solar and planetary, wide field and deep sky objects. Many cameras now include live view capability, which is important for convenient, accurate focusing. Newer cameras also allow video capture, which can be important when capturing short exposure lunar or planetary images. This allows the astrophotographer to accumulate dozens or perhaps even hundreds of video images. With the appropriate software, these images can be aligned from frame to frame to eliminate jitter from wind or atmospheric disturbances, as well as compensate for drift from poor tracking. Once aligned, these images can be graded and limited, so that only the best images (those that occurred during brief moments of superior seeing) are stacked together to reduce the thermal noise that is always present, to some degree, in the sensor and electronics. Capturing dark frame images and flat field images during the astrophotography session provide additional information to process with the raw images, to further reduce noise.

Seeing the entire process from image capture through image processing was particularly helpful. Daryl used his DSLR camera to capture several images during the program, demonstrating the adjustments for shutter speed and ISO value. He also discussed several useful image processing programs, including Nebulosity, Deep Sky Stacker and Registax. Using the latest version of Registax, he stepped through the entire process of loading a video file of Jupiter images, aligning all the images in the file to eliminate movement, limiting the image sequence to the 50 best frames before stacking to produce a processed image. The final step was to apply wavelet processing, which significantly enhanced the image, and got an immediate positive reaction from the audience.

Daryl's presentation provided ample evidence that the advanced capabilities and considerable flexibility of modern DSLR cameras make them ideal for a broad range of astrophotography projects. More club members are now likely to consider this as the preferred direction for their own astrophotographic success.

Next Meeting

Monday, May 2, Virgil Reese will present "Predicting the Future Evolution of the Universe" in the Bartlesville Public Library Meeting Room. For more information, see the meeting announcement on our website home page at <http://sites.google.com/site/bartlesvilleastronomyclub/> .

BAS Public Website: http://sites.google.com/site/bartlesvilleastronomyclub/

BAS Yahoo Group: http://tech.groups.yahoo.com/group/BvilleAstro/

If you want to have your email address removed from the Bartlesville Astronomical Society mailing list, please send an email requesting removal to bvilleastro@gmail.com .