Value chain · CLM-1277
In plain terms
A 2026 expert commentary says the 1970s studies behind the 230 watt beam limit looked only at calm conditions over mid-latitudes. In the author's view, the single limit should be replaced by one that changes with the state of the upper atmosphere.
The claim as recorded
A 2026 commentary in Space Weather states that "the early NASA work focused on quiet space weather conditions in the mid-latitude ionosphere", and argues, as its author's view, that because the threshold is expected to vary with climatological and space-weather conditions, the 230 W/m2 threshold set by DOE/NASA in 1978 "must be superseded by a more nuanced assessment that varies with ionospheric conditions".
Evidence behind this: T2: a peer-reviewed commentary; the author's reading of the literature and view, with no data.
Scope and limits
The second half is the commentary's opinion, not a measurement or a derived threshold, and it does not say what the condition-varying assessment would give. The commentary describes 230 W/m2 as a self-focusing threshold; the 1978 report gives approximately 23 mW/cm2 at 2450 MHz, based on self-focusing and thermal runaway together, and calls it theoretical (SRC-085 PDF p.41; see outputs/review/src588-read.md). Its "quiet ... mid-latitude" reading is the author's characterisation of the early work, citing one 1977 paper; it is not checked here against every early study. SRC-588 states that "No data were created or used in writing this commentary" (PDF p.4).
What it assumes
No assumptions are recorded against this claim.
Where it comes from
PDF p.2, text layer and render: the first quotation; same page, lower: "the 230 W m-2 threshold set by DOE/NASA (1978)" followed by the second quotation. The variation it names is "climatological (diurnal, annual and solar cycle)" and space weather, citing a 2004 study. The page prints U+2010 hyphens and a superscript minus 2; the quotations use ASCII.
Related records
- Answers question
- QST-009 not published in this releaseQST-010 not published in this release
Cite this
energyaperture.com/c/clm-1277
CLM-1277, Energy Aperture, as of 2026-08.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-588
- CLM-1278A 2026 expert commentary points out that the upper atmosphere would scatter a small share of a power beam, as it does a research radar's...CLM-1279A 2026 expert commentary suggests that power-satellite and grid operators at mid-latitudes might get about an hour's notice of space storms...