A historic rocket launch that will blast satellites into space from the UK's southwest coast will take place on Monday.
So long as the weather cooperates, the initial window for the Start Me Up mission will open at 10.16pm, when the LauncherOne system will be carried skyward from Spaceport Cornwall.
It will be nestled under the wing of a converted Boeing 747 nicknamed Cosmic Girl, and with it a payload of satellites, including a prototype orbiting factory for making high-value alloys and semiconductors.
The announcement of a launch date for the first orbital launch from UK soil - or anywhere in western Europe - comes after technical issues pushed it back from its pre-Christmas target.
But after a successful rehearsal on Thursday, organisers confirmed the Monday night timeslot.
Should bad weather or other problems present themselves between now and the launch window, backup dates have been earmarked for later in the week.
Melissa Thorpe, head of Spaceport Cornwall, described the launch date as a "phenomenal moment" that would "transform access to space across the world".
Preparation for the launch began to ramp up at the end of last year, with the Civil Aviation Authority granting the UK's first spaceport licence in November.
Virgin Orbit, the launch operator, was awarded its own licences the following month.
This week, licences were granted to each of the satellites being carried, among them the so-called Dover Pathfinder, designed in the UK by engineering company RHEATECH.
Pathfinder is the first step towards the creation of a constellation of satellites to safeguard the country's defence and critical national infrastructure, including power grids and communications networks, from hostile threats.
How will the launch work?
This will be a horizontal launch rather than a NASA-style vertical one.
Given Cosmic Girl is an old Boeing 747, the view from Spaceport Cornwall will not look dissimilar to any other plane taking off when it takes to the sky under the cover of night.
Under its left wing is LauncherOne, which will be released at 35,000ft over the Atlantic Ocean before accelerating to 8,000mph on its mission to deploy seven satellites into orbit.
Will you be able to see it?
You most likely will - in fact, it will be visible across the UK, Ireland, and parts of France, Portugal and Spain.
Maps released by Virgin Orbit, the launch operator, show when and where eagle-eyed space enthusiasts in each country can expect to see it in the sky.
The path of the 21m (69ft) rocket - which was designed by Virgin Orbit in California - is shown in blue, with the circles depicting its approximate location at each minute along the way.
Virgin Orbit says people in the UK and Ireland should be able to see LauncherOne within 60 seconds of ignition, while coastal regions in France, Portugal, and Spain will get a good view within two to three minutes.
The entire launch phase is estimated to last approximately 10 minutes.
What makes the mission so significant?
The UK has only ever completed one orbital launch, the Black Arrow in 1971, and that actually took off in Australia.
The Cornwall launch forms part of the government's National Space Strategy, and should pave the way for more.
Hoping to follow Start Me Up are launches from Scotland, specifically Sutherland and Shetland - and these will be vertical launches, again carrying satellites.
Ian Annett, deputy chief executive at the UK Space Agency, said the Cornwall launch marked the beginning of a "new era for space in the UK".
He said: "This will lead to new careers, improved productivity and inspire the next generation of space professionals, and this is just the beginning.
"I look forward to seeing more launches from other UK spaceports over the next year, putting us firmly on the map as Europe's leading destination for commercial small satellite launch."
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