"Signals" The NAAPO Newsletter Volume 20, No. 2; July 2004

Written by: Phil Barnhart, NAAPO Coordinator, 4655 Indian Ct., Westerville, OH 43082 Printer-Friendly Version

Coordinator's Corner    Phil Barnhart Progress is often accompanied by more sobering moments. We learned this week of the death of one of the world's pre-eminent radio astronomers. John Kraus was the heart and soul of radio astronomy in Ohio and the reason NAAPO came into being. His dedication to pursuing fundamental research in radio astronomy and his interest in the potential of the search for intelligent life elsewhere in the universe placed our unique organization in the position we occupy today. We mourn the loss of this great life almost as much as we suffered with John through the 'sell-out' of the Big Ear telescope for the purpose of fiscal expedience and the development of a few more holes of golf course for a county overrun with underused golf links. John deserved much better than this. We will miss the continued support and constructive criticism that he provided right to the end. It is appropriate that John's passing coincided closely with the detection of the first true astronomical object by Argus (24-element array). After months of monitoring geo-synchronous satellites, Russ Childers finally nailed the sun! Ability to track the sun across the sky continuously means we are back in the business of radio astronomy. We are now into problems inherent in all new observing programs; side lobes, sensitivity increase, noise reduction, component improvement, software development, etc., etc. We invite all friends of John to submit remembrances to our Big Ear web site. Feel free to send them to Jerry Ehman at ehman.1@osu.edu. In a casual encounter your coordinator met a 1999 volunteer, Danielle Douglas, in the Westerville Library. Danielle had joined NAAPO as a high school senior seeking a mentoring experience. She expressed an interest at that time in pursuing a career in astronomy. The general wisdom among the volunteers at the time was that she pursue an undergraduate degree in physics, then move into astronomy at the graduate level. Danielle started the scanning of the Campanella strip-chart record in search of "Whoa" type signals. In her brief encounter with the project she reported none found. Completion of the search still remains in the future. Danielle has reconsidered her goals and is now enrolled in a business course at Columbus State Community College.

Chief Observer: Russ Childers Russ Childers has re-integrated himself into the chief observer role. Russ has successfully undertaken the transfer of the receiving computers to the observing room to join the data analysis/display/data storage machines. The data acquisition task is carried out on computers operating under Windows OS while the data handling, display and archiving is on machines having Unix operating systems. For most of the winter/spring observations Russ has done the beam forming and recording using the GOES-12 satellite. This has allowed experimentation with the software and the gaining of understanding of the beam-forming algorithm. It also allows drift scans of the sky in the direction of GOES-12 by off-setting from the satellite frequency and maintaining the beam in the same direction. Early this summer, the sun was detected and tracked across the afternoon sky. With 24 active elements we are now doing 'real' astronomical observations. The main thrust of the observing program is presently an attempt to reduce (eliminate?) the numerous side-lobes presented by the compact array of antenna elements. We are awarding Russ the "Order of NAAPO Achievement" for this quarter. This award consists of a blank CD upon which he will be expected to archive a 20 minute run of raw data for the rest of the software team to work on in perfecting their programming skills and display performance. (Listen up Terry, Derek, Lee, et. al.)

Edwards Team Forges New Element Design Lee and Derek Edwards have put in extra hours developing a new structure for the individual antenna elements. We had decided some time ago to replace the composite wood box design because of unacceptable weathering. The idea was to transfer the antenna elements and input LNA's into revised open structure supports that could dry out in clear weather and still remain insect and atmospheric moisture free. The idea was to use milk crate-like structure to support the elements and keep them off the ground. In a quick move to salvage two badly deteriorated boxed elements they remounted the antenna, reflector planes and a mesh ground plane onto a framework constructed of composite plastic and wood commonly used for decks and railings. These were then placed in the existing array for testing. They seem to be working as well as the boxed elements they replace. Further testing will indicate if the elements can operate in the open, We are still prepared to encase them in fiberglass mesh. Russ Childers inspecting the new Edwards' design.

Missing Issues of NAAPO News/Signals Note! We are apparently still missing seven issues of the issues of NAAPO News/Signals for our on-line archive. The missing volume/issue numbers are: Volume 3: 1, 2, 3 Volume 4: 3 Volume 5: 5 Volume 8: 4 Volume 9: 7 The rest of the issues are now archived on line available for public access at www.naapo.org.

Current Data Rates Noted During the July 17 working session the question arose concerning the present rate of data acquisition, analysis, display and storage rates. A quick calculation yielded the following statistic. The waterfall display requires 0.2 seconds for each acquisition plus 1.3 seconds for analysis and display. This is 1.5 seconds to provide a new line of data in the waterfall display. To save these results occupies 2 MB every 1.5 seconds or the order of 100 MB per minute or 144 GB per day. This means our current terabyte (TB) of storage will fill up in less than 7 days. This is based on 32 elements even though data is now coming in from only 24. Russ pointed out that a 24 x 24 element cross-correlation for each of the frequency bins can be computed every 1.5 seconds. The possibility of stacking 192 processors in one rack, which would allow 192 independent analyses simultaneously, exists at the present time. The only thing needed to accomplish this is money.

Proposals in preparation stage Lee Edwards is gathering publications, figures and equipment requirements for the purpose of submitting proposals for funding to a variety of granting organizations. As soon as the all-sky display is cleaned up and the waterfall detection of a passing satellite is provided we should begin writing the proposal.

The IRS is Checking on Us Again Among the piles of junk mail arriving for Bob Dixon and the North American AstroPhysi . . . (sic) at our 'formal' mailing address an innocent looking windowed envelope from the IRS showed up recently. They remind us that as long as we do not take in more than $25,000 per year we do not have to file a Form 990. There are triplicate forms to fill out to assure them that we have not surpassed this amount (ever) and this task is now being undertaken by Barnhart in his spare time. Incidentally, the same IRS (United States, of course) is still trying to collect about $10,000 in taxes from us for the late 1980's. This is a long engaged battle. If they win we will probably declare bankruptcy and disappear slowly in the west -- further than we have so far.

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