A letter to UK science minister Sam Gyimah has outlined the impact of Brexit on Britain's space sector, and it doesn't make for happy reading.

The letter (PDF) by Lord Whitty follows oral evidence given to the Lords' EU Internal Market Sub-Committee on 15 March.

The committee followed up the session with a jolly to the "space cluster" at Harwell Campus near Oxford, where 800 people are employed in the sector.

Gyimah – who is Minister of State for Universities, Science, Research and Innovation – will be unsurprised to learn the top concern is the UK's involvement in the European Space Agency's (ESA) Galileo and Copernicus programmes.

Less than a month ago, the government shot a hurt look at its European neighbours when it finally realised that not being in the EU meant that, er, it wouldn't be a priority in EU plans for space.

Lord Whitty spelled out concerns of industry, with the assumption that the UK would not be participating in the future already having an effect in terms of decisions around staffing and supply chains.

Professor Sir Martin Sweeting, of Surrey Satellite Technology Ltd (SSTL), went as far as to warn that the situation threatens the viability of his company.

During the committee's visit to Harwell, ESA representatives also confirmed that the agency had been instructed by the European Commission to restrict access by UK companies to EU projects with security implications.

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It isn't all about Galileo, of course. ESA's Copernicus Earth observation programme is also being prodded with the Brexit stick. The witnesses observed that work would likely be shifted from the UK simply as a hedge against potential Brexit disruption.

The key conclusion and recommendation of the committee was that government needs to act quickly to reach an agreement that preserves UK access to EU space programmes.

The uncertainty is already having an impact and with UK companies potentially being hit by "Brexit clauses" in EU space programmes, government support may also be needed.

It wasn't all doom and gloom (OK, it was mainly doom and gloom) with the committee welcoming public funds being splurged on UK spaceports and Stuart Martin, CEO of investment outfit Satellite Applications Catapult, optimistic of a surge in private capital into the UK space sector.

Alas, the committee went on to warn that those measures alone will not compensate for the losses if government does not reach a deal quickly.

Disappointingly, the letter made no mention of Lord Mawson's smartphone-waving antics, which, for The Register at least, were the highlight of an otherwise gloomy session of evidence-giving.

The conclusions are, however, inescapable. Work that might have come the UK's way pre-Brexit and the skills required will go (and are going) elsewhere while uncertainty remains. The government needs to act quickly on agreements regarding space, customs and movement of people if it is to staunch the flow.

That said, while discussions between the UK and EU continue, there is some understanding and perhaps even sympathy within ESA for the UK's position.

An ESA insider told The Register "the fact the UK is leaving shows that something is not entirely right with the EU and that the EU needs some level of reform".®