It was one eclipse the Astronomer Royal had not wanted to see - and one that ultimately set him on collision course with council planners.

When residents in Caol near Fort William asked for his help in a row over a new school sports hall blocking their view of Ben Nevis, Professor John Brown fired a rocket at councillors in a blistering missive.

In an email circulated amongst councillors, Professor Brown said he had been consulted by residents about the new gymnasium and "the sunlight shadowing implications of the height of the building".

He continued: "The answer in brief is 'appalling'. I also note the fact that the council are in essence accusing a substantial group of elderly residents of lying by all claiming they did not receive the plans or chance to object. The fact that there are many must constitute 'the proof of the negative" that the council is outrageously demanding."

He had found it politically disillusioning, adding: "All of this is so disgusting from a party (SNP) claiming to have a caring human face that it has reversed my lifelong political thinking. Unless the SNP remedies this heartless, hypocritical decision (like pigs will fly) I will now be voting No in September and publicising my reasons widely. I am in the process of expressing my views directly to the First Minister."

But Mr Brown did not hold out much hope his views would be influential, concluding: "I no longer expect anyone in the local councils to give a toss what I think but at least I will be able sleep easily at nights."

Speaking to The Herald yesterday, Professor Brown said he hadn't briefed Mr Salmond, but had talked to the local SNP MSP. He explained why he had taken issue with the Highland Council's handling of the new £7m Gaelic Primary School for Fort William.

In particular, some elderly residents beside the site in Caol will lose the view they have always enjoyed of Ben Nevis because of the school's 40ft high sports hall.

Professor Brown, who lists being a magician amongst his hobbies and uses magic in his popular science talks, said: "The folk had been told they would get plenty of light in the winter, and she asked my opinion as being an astronomer it is something I know a bit about. So I got into it and asked for plans, but got no answer at all. So I started to get more and more exasperated. I was horrified by the photograph and the whole way the thing was being handled."

The council has an SNP/Lab/Lib Dem coalition administration, but Professor Brown had the SNP, as the largest party, in his sights.

Glasgow-based Professor Brown said he had heard from councillors privately that they had no idea the building would be so big. He also understood that the final plans had been approved by officials under delegated powers and not by a committee.

Caol Community Council has 100 letters of complaint from residents who claim they were "misled and poorly informed".

Lorna McCalman, whose elderly parents are directly affected, launched an online petition with more than 700 names. It urges the council "stop building a monstrous metal shed in front of old people's houses".

Highland Council said it had conducted a review and insisted correct planning processes had been followed. However it is understood the authority is now investigating whether the height and pitch of the sports hall can be reduced by up to 12ft.

Chairman of the Highland Council's Planning, Development and Infrastructure Committee, Inverness LibDem councillor Thomas Prag, said: "I am completely satisfied the local planning office has carried out all the correct and relevant processes with regard to the submission and assessment of the planning application."

He said the council had advertised the application and had run two pre-application consultation sessions last May where a 3D scale model was displayed.

Professor Brown sent his email to the SNP councillor for Caol and Mallaig Bill Clark who circulated it among other councillors.

He said of Mr Brown's comments: "He is so far off the mark and has since apologised for the tenor of his comments."

Mr Clark said the sports hall was higher than he had expected. "But that's what was agreed and what was presented in the model."

Professor Brown said of the council review: "It's just like the police monitoring the police."