The Newsletter of the Astronomical Society of Greenbelt
I apologize for the delay in releasing this newsletter. Elizabeth & I had several family obligations which popped up near the end of February.
Comet PanSTARRS has hit the popular media. Our 3/16 star party is squarely in the middle of the comet’s prime viewing time from 3/10 to 3/22. I think it’s likely that we will see a larger crowd than we normally get at a star party, especially if the weather turns mild. We may have to deal with some disappointment, given our so-so western horizon & that an object no brighter than the 3rd magnitude will have to compete with our region’s light pollution.
Elected officers for 2012-2013
martylou AT gmail.com
stvns.jacht AT yahoo.com
Cleton.Henry AT gmail.com
wb3enm AT amsat.org
Astronomical Events Around Greenbelt in March 2013
Star party @ Northway Field @ 7 PM
Owens Science Center: Public Planetarium show
Star party @ Northway Field @ 8:30
Sidewalk astronomy @ Roosevelt Center @ 7
General meeting @ the Owens @ 7:30
Star party @ Northway Field @ 8:30
For other astronomical events in the DC area, see: Astronomy in DC
Star Party & Business Meeting Reports
Feb . 2: Star Party: Snowed out.
Feb. 4: Officers’ meeting: [Report from Cleton]:
Present at the meeting: Martha, Ray, Doug, Cleton
Excuses of absence made for: Craig, Elizabeth, Sue
We discussed the "GATES" opportunity (Hope I have the acronym correctly). This would involve the sponsors coming to the observatory and publishing aspects of our activities.
Needs to be done when many people can participate, therefore warmer weather is preferred - Spring, Summer? We could provide a tour of the observatory. Consider starting early in the evening before dark to discuss astronomy stuff and and then morph into the post-dark activities. Consider filming some teaching or training sessions to be available for future purposes.
Some observatory issues:The belt that turns the dome probably needs replacing. We might have to consider a "patch-up" job if a replacement is difficult to locate. Doug and Martha will research the replacement options.
Martha will contact Goddard's Astronomy Club to see if they are any potential speakers available.
As part of our public out reach, we should consider sourcing training or presentation material from ALCOR. This material would include films, slides, YouTube videos, etc.
There being no further business, the meeting was adjourned at 8:50 pm.
Feb. 16 & 17: Star Party & Sidewalk Astronomy: Clouded out
Feb. 28: Monthly Meeting: [Report adapted from correspondence from Martha & Shalom]:
Dr. Tilak Hewagawa talked about measuring trace components in the atmospheres of Titan & Mars using spectroscopy, mostly in the infrared region. He illustrated the difference that spectroscopic resolution makes and showed how one can separate signals generated in the Earth's atmosphere from those of Mars using the Doppler shift, which results from the differential velocity of the two planets. Essentially, the gases in Mars’ atmosphere are moving towards or away from us, but the gases in our atmosphere are more or less travelling with us, so their spectral lines will fall in a slightly different space. Dr. Hewagawa also discussed the possibility of methane on Mars, measured from Mauna Kea. The imaging spectrometers in orbit around Mars do not have the requisite resolution to observe it. The methane is an
evanescent phenomena because its lifetime is limited. It can only be observed during oppositions of Mars. The measurements are controversial, some doubt the conclusion that methane was seen. It could be an indication of life, since living organisms can produce methane. Hopefully, better instruments will be in place for the next opposition.
Another highlight was the production of a chart devised by a clever graduate student. This chart had the ordinate as the ratio of 350nm/550 nm and the ratio of 850 nm/550nm light observed reflecting from planetary atmospheres. It showed the Earth as an outlier compared to the Jovian planets, as well as Mars and Venus. Perhaps this type of measurement will allow an assessment of the atmospheres of exo-planets to see if any are Earth-like. Furthermore, the ozone absorption of UV-which you can assume given detection of oxygen in a planet’s atmosphere- acts like a possible extender of the habitable zone of stars. If a planet is close to the inner edge of the HZ, the ozone will shield the planet and keep the surface cooler. If a planet is close to the outer edge of the HZ, then the ozone will thin and enable sunlight to reach the surface, keeping it warmer. Such extensions of the habitable zone might enable the cooler K
type stars to have habitable planets. Since the population of nearby K stars is fairly large, then a search for HZ planets about such stars might prove rewarding.
Dr. Hewagawa also discussed some new techniques to make instruments smaller and lighter - and therefore cheaper to launch. All in all an interesting talk.
Operation Moonwatch Satellite Scope, Leaping Robot Blog, and Small World!
by G.W. Gliba
While looking online for more information on Moonwatch Satellite Scopes recently, a subject of historical interest to me, I came across an article by Dr. W. Patrick McCray, author of the book "Keep Watching the Skies: The Story of Operation Moonwatch and the Dawn of the Space Age". It was posted on a blog called "Leaping Robot Blog" posted on February 6, 2013 titled "Apprehending the Artifact". To my great surprise, it was about how, after meeting him after he gave a talk on this book at the NASA/GSFC weekly Friday Goddard Colloquium in Bldg #3 back in 2008, he told me he didn't have a Moonwatch Telescope, but would like to get one someday. Well, I eventually found one and sent it to him. I had no idea he would blog it to the world, but I think it is good publicity for the NASA/GSFC. Here is the link to the blog: http://www.patrickmccray.com/tag/telescopes/.
After forwarding the link to this blog to members of the NASA/GSFC ASD E/PO group, because I thought that they might find it of interest, I got a reply from Dr. William R. Oegerle, who is the director of the Astrophysics Science Division. In his own words he wrote: "Drake Deming is a friend of mine. He used to work here at Goddard in code 690, and is now a professor at UMD. Drake grew up in Terre Haute, Indiana and he told me that his father was an amateur astronomer. When I saw the picture in the blog article about the Moonwatch team from Terre Haute (taken in 1957!), I sent it off to Drake asking him if his father was in the picture (I mean, how many astronomers could there have been in Terre Haute in 1957, right?). Well, Drake responds that his father is not in that picture because his father TOOK the picture! And the little boy in the front right row is Drake himself. Drake also says if you look at the very last photograph, where folks are looking through telescopes in a line, you will see a thing that looks like rabbit ears in the distant back. That's a WWII military spotting binocular. It currently resides in Drake's garage!"
I then emailed Dr. W. Patrick McCray, thanking him for the excellent blog reference, and telling him about the wonderful story from Bill Oegerle about former NASA/GSFC astronomer and University of Maryland professor Dr. Drake Deming. His reply was: "Thanks for the nice note. I was hoping you might get some sort of alert etc re: the recent blog post. That is also super cool re: Drake Deming. I had no idea he was practically in my backyard as I worked on the Moonwatch book while living in DC. Small world! Thanks again for making my day with this." Small world indeed!