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Path: ...!weretis.net!feeder9.news.weretis.net!i2pn.org!i2pn2.org!.POSTED!not-for-mail From: hertz778@gmail.com (rhertz) Newsgroups: sci.physics.relativity Subject: Re: The Shapiro's experiment HOAX. A 1968 TIME article. Date: Mon, 14 Oct 2024 02:18:01 +0000 Organization: novaBBS Message-ID: <c9c2b4f1367a4be8f5d4cc2de4c80533@www.novabbs.com> References: <db18709b6ba689b9c07245000ff1b094@www.novabbs.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Info: i2pn2.org; logging-data="1934634"; mail-complaints-to="usenet@i2pn2.org"; posting-account="OjDMvaaXMeeN/7kNOPQl+dWI+zbnIp3mGAHMVhZ2e/A"; User-Agent: Rocksolid Light X-Rslight-Site: $2y$10$L6U5aKHmOD1hZ3NBdUxkWuBJtOoHdmOUb.yXmP.pxKOaeqFDF/QyC X-Rslight-Posting-User: 26080b4f8b9f153eb24ebbc1b47c4c36ee247939 X-Spam-Checker-Version: SpamAssassin 4.0.0 Bytes: 2781 Lines: 70 CORRECTION FROM PREVIOUS POST: The difference that allegedly was measured was 1/5 msec or 200 microseconds. So, the alleged accuracy was 1.45E-07 or 0.145 ppm (in 1964!, with ad-hoc real time computers built in that epoch. ******************************************************************* The Haystack radar antenna is a 120 ft diameter Cassegrain system designed and built in the 1960s. QUOTE: 1965- Irwin Shapiro proposed a “fourth” test of general relativity— measuring the general-relativity prediction of “time dilation” or “excess delay” up to ~200 microseconds for radio waves that travel very near the Sun. He suggested that radar measurements of a planet near superior conjunction should double the one-way value; this value would be compared to the total round-trip time of up to ~1500 seconds. The first results from a radar-echo excess-delay experiment were obtained in 1967 using Mercury as a target https://archive.ll.mit.edu/publications/HaystackCommemorativeBk.pdf In the 60s it operated at 8 Ghz, with a power of about 200,000 Watts. In a round trip of about 2 x 200 million Km, the FSPL (Free Space Path Loss) is FSPL(dB) = 20 log d + 20 log f - 147.55 d: distance in meters f: frequency in Hertz FSPL(dB) = 20 log 4E+11 + 20 log 8E+09 - 147.55 FSPL(dB) = 220 log 4 + 180 log 8 - 147.55 = 147.45 60dB have to be added due to the passive reflection in Mercury. Received power (dBW): -207.45 + + 5.3 = -202.15 dBW Antenna gain (at reception) = 61 dB Beamwidth = 0.07 degrees Received power (W): 10E-07 Watts = 100 nanowatts Noise at reception (W, estimated) = ? nanowatts (depends on many factors), like bandwidth, technologies, cosmic sources, etc. https://repository.aip.org/islandora/object/nbla:307780