<div dir="ltr"><br>Dear colleagues:<div><br></div><div> The Arecibo Science Advocacy Partnership (ASAP) is inviting Dale Ferguson to talk about his ideas on how to restore some of the Arecibo 305m radio-telescope capabilities, mostly related to the Aeronomy facilities.   The Arecibo platform collapsed in December 2020.  However, the collapse did not affect the expensive transmitters, generators, and other crucial instrumentation used for the ISR and HF facilities.  At the talk, Dale will present a plan to restart ionospheric and satellite observations at Arecibo, using the existing infrastructure and performing some basic repairs.  </div><div><br></div><div>ASAP is interested in hearing your feedback as part of the CEDAR community.  Please save the date and join us.<span class="gmail-Apple-converted-space"> </span></div><div><br></div><div>On behalf of the ASAP board,</div><div><br></div><div><br></div><div>Eliana Nossa</div><div><br></div><div><div class="gmail_quote"><br><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div dir="auto" style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div dir="auto" style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div dir="auto" style="word-wrap:break-word;line-break:after-white-space"><div style="word-wrap:break-word;line-break:after-white-space"><div class="gmail_quote"><img id="m_7786405135474333958gmail-m_8812838433700971889gmail-m_-29999260328924249078267ABD-88B1-4B63-A122-E405EAF0DB6F" src="cid:181ba50f33af0a0707e1"><br><br><br><br><span><br><span style="font-size:14px">Dear Colleagues,</span><br style="font-size:12px"><div><div style="font-size:12px"><div class="gmail_quote"><span style="font-size:14px"><span style="white-space:pre-wrap">     </span></span><span style="font-size:14px">Lecture/Discussion: Thurs., 7th July, 12 noon ET</span></div><div class="gmail_quote"><span style="font-size:14px"><span style="white-space:pre-wrap">       </span>Title: <i>A Preliminary Plan to Quickly Restore Utility to the Arecibo 305m Telescope</i></span></div><div class="gmail_quote"><span style="font-size:14px"><span style="white-space:pre-wrap">   </span>Dr. Dale Ferguson — </span><span style="font-size:14px">AFRL Spaceforce</span></div><div class="gmail_quote"><span style="font-size:14px"><span style="white-space:pre-wrap">                 </span>(A fuller biography is given below)</span></div><div class="gmail_quote"><span style="font-size:14px"><span style="white-space:pre-wrap">      </span>Zoom Link: To be sent 24-48 hours prior to the event</span></div><div class="gmail_quote"><span style="font-size:14px"><div class="gmail_quote" style="font-size:12px"><b style="font-size:14px"><i><span style="white-space:pre-wrap">        </span></i></b></div><div><br></div></span></div></div><div class="gmail_quote"><span><span><b style="font-size:14px">Abstract:</b><div><div class="gmail_quote"><span style="font-size:14px"><span><span style="font-weight:bold;white-space:pre-wrap">      </span></span></span><span style="font-size:14px">Since the collapse of the Arecibo 305m telescope platform on Dec. 1, 2020, </span><span style="font-size:14px">there </span><span style="font-size:14px">has been much discussion of building a new Arecibo telescope or rebuilding </span><span style="font-size:14px">the</span><span style="font-size:14px"> </span><span style="font-size:14px">facility that was destroyed. In the collapse, the tops of the three platform </span><span style="font-size:14px">support </span><span style="font-size:14px">towers were sheared off, and the feed arm fell free from the swinging platform and </span><span style="font-size:14px">destroyed 25% of the dish. Fortunately, the Control Building, with the computers, </span><span style="font-size:14px">spectrometers, masers, atomic clocks, 430 MHz Klystrons, etc., was spared. </span><span style="font-size:14px;white-space:pre-wrap">   </span></div><div class="gmail_quote"><span style="font-size:14px">By replacing the main dish support cables and resurfacing with coarse mesh, </span>the<span style="font-size:14px"> main dish can be repaired as a reflector for < HF operation.  By replacing the </span><span style="font-size:14px">damaged aluminum panels to make the dish whole again, RF operations at up to </span><span style="font-size:14px">500 MHz can be resumed. In this presentation, we outline the steps that can be </span><span style="font-size:14px">taken to restore HF (High Frequency, 3-30 MHz) ionospheric heating, 430 MHz </span><span style="font-size:14px">ionospheric incoherent scattering radar, passive radio observations of satellite </span><span style="font-size:14px">arcing and pulsars, and to extend the field of view to 47 degrees from the zenith. </span><span style="font-size:14px">This would restore and improve much of the utility of the Arecibo dish. Part of this </span><span style="font-size:14px">plan involves supporting, positioning and pointing novel point feeds from lightweight </span><span style="font-size:14px">football-camera-like cables, strung from the rebuilt tower tops. It is believed that </span><span style="font-size:14px">the </span><span style="font-size:14px">dish may thus become broadly useful long before replacement</span><span style="font-size:14px"> </span><span style="font-size:14px">facilities can be </span><span style="font-size:14px">engineered and constructed.</span></div></div><div style="font-size:14px"><span><br></span></div></span></span></div><div class="gmail_quote" style="font-size:12px"><span style="font-size:14px">This event is a further in the series of ASAP “lunchtime” talks/discussions </span><span style="font-size:14px">exploring </span><span style="font-size:14px">issues </span><span style="font-size:14px">and </span><span style="font-size:14px">proposals pertinent </span><span style="font-size:14px">to Arecibo’s future.  Recordings of the earlier talks can </span><span style="font-size:14px">be found on </span><span style="font-size:14px">the </span><a href="http://areciboscience.org/" target="_blank" style="font-size:14px">areciboscience.org</a><span style="font-size:14px"> website.  </span></div><div class="gmail_quote" style="font-size:12px"><span style="font-size:14px"><br></span></div><div class="gmail_quote"><div class="gmail_quote" style="font-size:12px"><span style="font-size:14px">Please reserve the date, and </span><span style="font-size:14px">look for the zoom link to be sent </span><span style="font-size:14px">24-48 hours prior  </span><span style="font-size:14px">to the event.</span></div><div class="gmail_quote" style="font-size:12px"><span style="font-size:14px"><br></span></div><div class="gmail_quote" style="font-size:12px"><span style="font-size:14px"><span style="white-space:pre-wrap">             </span>Best regards and wishes,</span></div><div class="gmail_quote" style="font-size:12px"><span style="font-size:14px;white-space:pre-wrap">                      </span><span style="font-size:14px">ASAP Secretary</span></div><div class="gmail_quote" style="font-size:12px"><br></div><div class="gmail_quote"><font color="#5856d6" face="Calibri, sans-serif"><span><br><br><br><span style="font-size:14px">Dale C. Ferguson received the Ph.D. degree from The University of Arizona, Tucson, in 1974. </span></span></font><span style="font-size:14px;color:rgb(88,86,214);font-family:Calibri,sans-serif">He is currently the Lead for Spacecraft Charging Science and Technology with the Space Vehicles </span><span style="font-size:14px;color:rgb(88,86,214);font-family:Calibri,sans-serif">Division, Air Force Research Laboratory (AFRL), Kirtland Air Force Base, Albuquerque, NM. </span><span style="font-size:14px;color:rgb(88,86,214);font-family:Calibri,sans-serif">From 1978 TO 1981 Dale was a pulsar staff member at Arecibo. Since 1982, he has been </span><span style="font-size:14px;color:rgb(88,86,214);font-family:Calibri,sans-serif">addressing spacecraft charging problems.  In 2018-2019, he spent six months in the Arecibo </span><span style="font-size:14px;color:rgb(88,86,214);font-family:Calibri,sans-serif">Observatory developing and deploying an instrument to measure spacecraft charging known </span><span style="font-size:14px;color:rgb(88,86,214);font-family:Calibri,sans-serif">as the AFRL DAGGER Project.  The broadband 327 MHz "Point Feed" was located at the focal </span><span style="font-size:14px;color:rgb(88,86,214);font-family:Calibri,sans-serif">surface of the Arecibo dish.  </span></div></div></div></span></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div></div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><di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