Richmond Astronomical Society
790th Consecutive Meeting
July 14, 2015
Greetings – approximately 29 in attendance at the meeting.
Jim Browder called our meeting to order in the Eureka meeting room
Announcements / Share Table
Leslie had a focuser, dew shield, and a 6” lens for sale
Ken showed us a tour video of the Von Braun Astronomical Society planetarium in Huntsville, Alabama. It can be found on its website at www.vbas.com.
Library Report: none
Welcome Visitors:
Tom Stepka
Alex van Rooyan
Andrew Chase
Marie Barnett (wife of our John Barnett)
Events and Individual Observing:
RAS member observing
Mearl discussed that at the Outer Banks, when the sea turtles are hatching, no one is allowed to have front porch lights on. It must remain dark for the turtles to live. Light increases the chance of them going to the lights and not to the ocean.
Other members said they saw a meteor explode at Wrightsville Beach. It was a very dark and clear sky at the time.
Science Museum – weathered out
Green Bank Star Quest
Belmead – Weathered out. There was an indoor session, but no outdoor session.
The RAS and others are trying to get Belmead considered as a Dark Sky sanctuary. It will provide legal protection, if it is regularly visited. To qualify, it must allow star sightings of magnitude 21.5.
Powhatan State Park – JohnR – Venus, Jupiter, Mars; good crowd
Upcoming Events
Dark Sky Park Dedication at Staunton River State Park, July 17, 7:00 PM: Staunton River State Park has been named a Dark Sky Park by the International Dark Sky Association! RAS members, friends are invited to attend a dedication ceremony on Friday, July 17 at 7:00 PM near the visitor center in Staunton River State Park. An observing session will follow the dedication ceremony, weather permitting. An excerpt from the press release follows:
“(TUCSON, Ariz., and RICHMOND) — Staunton River State Park, in Scottsburg, has been named an International Dark Sky Park by the International Dark-Sky Association (IDA), becoming the first park in Virginia and only the 25th park in the world with the designation. Staunton River State Park is managed by the Virginia Department of Conservation and Recreation (DCR)”
Staunton River State Park management has worked very hard to achieve Dark Sky Park status in conjunction with the Chapel Hill Astronomical and Observational Society (CHAOS). Achieving this milestone required securing the support of surrounding communities, making a substantial number of sky darkness measurements, development of strategic plans for maintaining and protecting the dark skies and compiling all of this information in a lengthy application document. Many organizations, including RAS, submitted letters of support. As amateur astronomers, we owe our continued support to the Park for this monumental achievement.
Please join in the dedication ceremony if you can.
Several members will be attending.
Powhatan has new lighting laws. Madhu discussed a dark site about 10 miles west of Powhatan.
Science Museum Skywatch, Friday, July 17, 7:00 PM: Our regular monthly skywatch at the Science Museum is scheduled to start at 7:00 PM, but we might want to have some astronomers set up closer to dusk. If those of us who will be helping out with the skywatch can be at the Museum closer to dusk it would be helpful since there may be visitors at that time. The LiveSky will be from 6:30-7:30 about Pluto.
Powhatan State Park Skywatch, Saturday, August 8: RAS and Powhatan State Park will host a skywatch at the Park on May 16 starting at dusk in the equestrian parking area. Please join us if you can. If you can help with this event, please contact John Raymond at raymond7419verizon.net.
RAS Monthly Meeting, Tuesday, August11, 7:30 PM, Science Museum of Virginia: Please join us for the meeting and, if you can, for dinner at Arby’s, across the street from the Museum about 6:00 PM.
For those that cannot attend the meeting in person, we will stream video of the meeting, internet bandwidth permitting, at this link:
http://www.ustream.tv/channel/richastro
Annual Meeting of the Virginia Association of Astronomical Societies, October 3, Charlottesville: The annual meeting of the Virginia Association of Astronomical Societies is being hosted this year by the Charlottesville Astronomical Society. Please see the RAS updates for more details as they become available. More details will be made available on the RAS web site and at http://cvilleastro.com/vaas-2015/. If anyone wishes to help with the VAAS meeting, please contact president@richastro.org or contact the Charlottesville club directly.
East coast Star Party, October 8-10, Coinjock, NC: Casual stargazing in a dark sky coastal environment at the Hampton Lodge Camping Resort. Contact Kent Blackwell for more information at kent@exis.net.
Staunton River Star Party, October 12-18, Staunton River State Park: Excellent facilities in a southern Virginia dark sky. More information at http://www.chaosastro.com/starparty/.
Break
Discussion: ‘Detecting Exoplanets with a DSLR Camera,” Brent Maynard (presented by Jim Browder)
Brent Maynard and Jim Browder presented a method of detecting possible exoplanets. This compares to the method described to us by Emily W at an earlier meeting.
Brent talked about a simple way to use a DSLR to measure or detect light changes. Using photometry, he proposed to measure the flux in the light emitted from the star as the planet made a transit across it.
To start the process, a sample star and planet were selected from the Exoplanet Transit database. Over the course of a few hours during a transit, equipment can detect changes in the star’s magnitude.
Jim demonstrated how IRIS, the photometric software, can be used to detect the expected flux. IRIS is free astronomical software. It is powerfully nice but not user friendly. It gives no error message – you need to recognize that something went wrong. IRIS works by analyzing photos taken over a short period of time. As long as each photo covers the same size and area of the sky, it can detect changes. It will take each photo and align the multiple stars that appear on the photo with the previous photos. It then goes back and analyzes each of the stars in each image for fluctuations in light intensity.
Magnitudes are displayed for each star and can even be charted on a graph.
Brent has a website at http://www.astrogazer.us
The following can be found on his site to help you start looking for exoplanets
http://the-maynards.us/wp/wp-content/uploads/2014/07/transitphotometry.pptx
http://the-maynards.us/wp/wp-content/uploads/2014/07/DetectExoplaneTransitUsingDSLR.pdf