On Tuesday morning, six people will gather in the Fellows’ Room at the Royal Institute of Natural Philosophy on Arundel Crescent, and the question they face is deceptively simple: what lies beneath the Greymoor Highlands?

The answer — or rather, the plan for finding the answer — will shape the timeline of the tramway expansion, the viability of domestic copper production, and the future of a ridge that has, over the past month, revealed itself to be something considerably more interesting than anyone expected.

The panel, announced Saturday by the Royal Institute, is chaired by Professor Elara Whitstone, the Institute’s president and a volcanologist of international standing. Its five other members are Dr Odette Collis (the retired mathematics teacher who first documented the luminous phenomenon above the ridge), Dr Maren Ilkley (the Royal Institute spectroscopist who has been analysing the glow’s emission spectrum), a seismologist from Bobington Polytechnic, a mining geologist, and Nils Haversten, chairman of the Miners’ Cooperative of Greymoor.

Haversten’s presence is significant. The cooperative’s two thousand tonnes of annual copper production — a fraction of the tramway’s twelve-thousand-tonne requirement, but the only domestic source — depends on the same ridge that is now venting ionised nitrogen and sulphur dioxide through fractured rock.

What We Know

The facts, assembled over a frenetic fortnight, are these. Since at least 3 February, a persistent greenish-white glow has been visible above the Greymoor ridge on clear nights, documented by Dr Collis from the Cartwright Observatory. Spectroscopic analysis by Collis and Ilkley on 26 February revealed emission lines consistent with geothermal venting — superheated gases escaping through fractured rock.

A second observation on 27 February mapped the phenomenon across a roughly three-kilometre stretch of ridgeline running north-northeast to south-southwest, with at least four discrete emission points sharing the same spectral signature. Whitstone’s conclusion: “This is not a single vent. It is a system.”

That system runs through the zones containing the most promising deep copper deposits — the same deposits that Whitstone’s own testimony to the commission described as “declining in grade at depth” with an unmapped north-south fault at approximately four kilometres.

And on 23 February, a seismic tremor — the first in eleven years — was recorded in the Highlands, originating at roughly four-kilometre depth along that very fault.

What the Panel Must Decide

The commission’s interim report mandates a “comprehensive geological and geothermal survey” at an estimated cost of 1.2 million florins over four months. But the scope of such a survey is precisely what Tuesday’s panel must define. How deep? How wide? What instruments? What constitutes a satisfactory answer?

The geothermal dimension adds considerable complexity. A straightforward mining geology survey — core samples, grade analysis, structural mapping — is well-understood work. But integrating geothermal assessment requires different expertise, different equipment, and a fundamentally different set of questions. Is the venting stable? Is it increasing? Does it pose a risk to mining operations, or — more speculatively — might it represent a resource in its own right?

The panel is also expected to consider a permanent monitoring station on the ridge: 180,000 florins to construct, 45,000 per year to operate. If approved, it would be the first sustained scientific presence on Greymoor since a meteorological outpost was abandoned in the 1950s.

Dr Collis, who has made the glow visible to the world through systematic observation and a retired schoolteacher’s patient methodology, put it with characteristic simplicity: “The ridge is alive. The question is what it is doing, and whether it intends to continue.”

The Timeline Pressure

The commission’s final report is due Thursday. If the council debates and accepts the phased approach — as now seems likely — Phase 1 of the tramway cannot break ground until the geological survey is complete. The interim report places the survey at four months from commissioning. But commissioning requires funding, which requires a council vote, which requires the final report.

The earliest realistic start for the survey is April, which places completion in August. Phase 1 groundbreaking, once planned for autumn 2026, has already slipped to late 2026 or early 2027. Every week the panel’s recommendations take to finalise adds to that delay — and, as Chief Transit Engineer Okonkwo has testified, delay costs the city two to three million florins per week in idle infrastructure.

Haversten, the practical miner among the scientists, has been characteristically blunt. “You can survey a ridge until the end of time,” he told this correspondent on Saturday. “At some point, you have to decide whether you are going to dig or not.”

The panel’s recommendations will feed directly into Thursday’s final report. What happens at Arundel Crescent on Tuesday morning will echo through the Municipal Chamber for months to come.