Scenes of pandemonium greeted half-term crowds as they flocked to see Preston's Museum of the Moon exhibition today.
The 23ft lunar installation, which opened to the public on February 2, is already one of the most visited exhibitions in the Harris' long and illustrious history.
But a record numbers of visitors has led to chaos this afternoon, with frustrated families forced to queue for upto an hour to see the planetarium.
Crowds of parents and children could be seen snaking around the halls and stairways of the Harris Museum and out onto Flag Market.
Staff at the Harris acknowledged that the Museum of the Moon has become a victim of its own success, with the giant illuminated moon capturing the imagination of children and adults.
Bob Flood, from Leyland, said he was eager to learn what all the fuss was when he took his family to the unique installation on Thursday afternoon (February 21).
But Mr Flood's first impression was not the rave review that the Harris has come to expect from visitors to the lunar landscape.
Expressing his frustration on Twitter, Mr Flood said: "Blimey, it's not so much a #museumofthemoon, more like #museumofthequeueing."
After queuing for nearly an hour in the Harris' halls and stairways for a glimpse of the giant three-dimensional moon, Mr Flood's patience finally cracked.
He said: "There were so many people lining up on the stairs, it had become a potential health risk.
"I think the event has been poorly thought out, with limited tickets available for the planetarium."
But even an exasperated Mr Flood could not help praising the Harris after his turn came to view the moon up close.
Mr Flood said he stood "in awe" at the size and detail of the installation.
He said: "It was and is very good. Just a lot of people and children were disappointed at not seeing the planetarium show."
A spokesman for the Harris' Museum of the Moon exhibition swiftly apologised and said the moon had generated "unprecedented demand".
The spokesman said: “We’d like to say thank you to everyone that has visited so far and sent in lovely photos and comments.
"We’d also like to say sorry to those that are disappointed about tickets to events being sold out.
"We are listening to your feedback and we are going to put our heads together and make this a better experience for future shows.
“We’ve had unprecedented numbers in the Harris this month. If you haven’t yet come to visit, do pop in and stand in awe of the magnificent moon.
"Tickets for Friday’s planetarium shows will be released at 10am tomorrow morning on a first come first serve basis.
"For those that don’t get hold of planetarium tickets, visitors can still come and see the moon and exhibition."
The Museum of the Moon will run at the Harris Museum until Sunday, February 24.