Value chain · CLM-0032
In plain terms
In 2007 the international radio science union published a white paper saying that nobody had measured this heating effect from the ground at these frequencies, and only calculations existed. The 1978 figure was repeated not in that white paper but in the longer report attached to it, which is a separate document.
The claim as recorded
The URSI White Paper on Solar Power Satellites, published in Radio Science Bulletin No 321 of June 2007 after more than three years of work, states at printed p22 that no ground-based measurements of electron heating by high-power microwaves are available in the GHz range and that only theoretical estimates exist, for 3 GHz; it prints no mW/cm2 figure at all, its power-density figures being 300 W/m2 peak, 10 W/m2 at the periphery, a proposed 230 to 1000 W/m2 range and 500 W/m2 for E-layer heating. The separately attached Report of the same Working Group, not part of RSB 321, is where the 23 mW/cm2 figure appears, five times, and where the unqualified sentence sits, itself hedged as being to the authors' knowledge.
Evidence behind this: RE-GRADED T2 to T4 on 2026-09-11, under the weakest-source rule. The weakest cited source is SRC-052, the URSI White Paper on SPS Systems in The Radio Science Bulletin - a position document at T4, not a measurement. Both load-bearing statements were confirmed first-hand by image render at printed p.21, the text layer being unrecoverable exactly as the source row records: the no-measurements statement carries both qualifiers this claim restores, "ground-based" and "in the GHz range", and the 500 W/m2 E-layer figure is present. The page uses W/m2 throughout and prints no mW/cm2 figure, which is what supports the scoped negative.
Scope and limits
The corpus copy of SRC-052 has an unrecoverable text layer - embedded Type1 font subsets with no ToUnicode mapping, so extraction returns raw byte codes - and requires OCR to search. The two load-bearing statements in this claim therefore remain unconfirmed first-hand and must be confirmed before publication. UPDATED 2026-09-04: both load-bearing statements have now been confirmed FIRST-HAND, at SRC-052 printed p21 by image render and against the identical White Paper text in SRC-100, so the earlier caveat that they were unconfirmed no longer applies. SRC-100 binds two documents of DIFFERENT STANDING and they must not be conflated: the White Paper, 38 printed pages, published in RSB 321 pp13-27, and the separately attached Report, printed pp39-173, which RSB 321's own editorial describes as a document separate from the White Paper. This claim may not be used to attribute any Report statement to the White Paper or to RSB 321. A URSI White Paper is also NOT a consensus instrument: it is issued by URSI scientific experts on controversial subjects and, in its own words, does not necessarily reflect all the views of individual URSI Member Committees nor Commissions, so it may not be cited as the agreed position of the union. The book's preface (SRC-100 PDF p3, printed i) also says the White Paper "was approved by the scientific commissions and the national commissions"; that approval does not make it a statement of every Member Committee's view.
What it assumes
No assumptions are recorded against this claim.
Where it comes from
Document identity and provenance read first-hand from the corpus copy, p3 verbatim: "the URSI Inter-Commission Working Group on SPS and the URSI Board have been working on writing and reviewing an URSI White Paper on Solar Power Satellites ... the result of more than three years of work". Leadership named on the same page as Hiroshi Matsumoto and Kozo Hashimoto in the Working Group, Kristian Schlegel on the Board. No-measurements statement, first-hand: SRC-100 PDF p42 (printed p22), "No ground-based measurements of electron heating by high-power microwaves are available in the GHz range; only theoretical estimates exist for a frequency of 3 GHz [43]", identical at SRC-052 printed p21 by image render. The 23 mW/cm2 figure is not in the White Paper; it is in the attached Report, where the hedged sentence is at SRC-100 PDF p168 (printed p147): "To our knowledge no measurements of electron heating from high power microwaves in the ionosphere exist."
Related records
- Answers question
- QST-009 not published in this release
Cite this
energyaperture.com/c/clm-0032
CLM-0032, Energy Aperture, as of 2007-06.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-052
- CLM-0137In four major space solar power studies from 1978 to 2007, none put a number on how much of the beam's energy would be lost if the beam...
- Also from SRC-100
- CLM-0047Heating falls with the square of frequency. In 2007 no ground-based measurement of it was available at gigahertz frequencies, and...CLM-0048An international scientific body reviewed the proposed figures, found them ranging from 230 to 1,000 watts per square metre, and chose 300...CLM-0049The stated design intent in a 2007 URSI white paper is that the beam would be shaped to fall to 10 watts per square metre by the edge of...CLM-0067According to a 2007 international report, Japanese designs of the time chose their beam strength on cost and land grounds; the report does...CLM-0079The 1978 paper modelled both a ground facility and a satellite case, and its 500 watts per square metre figure is a power flux for a given...CLM-0083The formula is the right type but nobody has said how far it can be pushed, and at space solar power frequencies the wave is about 200...CLM-0101The 1978 contract required the researchers to report fixes if ionospheric disturbance pushed the pilot-beam phase error past 2 to 3...CLM-0137In four major space solar power studies from 1978 to 2007, none put a number on how much of the beam's energy would be lost if the beam...More on the source page.