Pink Floyd may have immortalised the mystery of the dark side of the Moon, but the other side of the Sun remains an even bigger enigma that is yet to be uncovered.
And we'll finally glimpse what unexplored regions lie behind the Sun two years or so from now, when the EURO1.5bn Solar Orbiter - a European Space Agency mission - begins to orbit the star at the heart of our solar system.
The spacecraft, due to launch from Cape Canaveral on Sunday night, will be the first to probe the Sun at close quarters, carrying out unprecedented observations of its poles and investigating the solar winds as they flow towards the Earth.
The mission, which has been gestating away for some 20 years, will uncover some of the great unexplored realms of our solar system, according to astrophysicist Professor Louise Harra, director of PMOD/WRC, the Physiological Meteorological Observatory/World Radiation Centre in Davos.
The Lurgan-born scientist is currently in Orlando preparing for the launch of the Solar Orbiter on Sunday night. It's a career highlight and there to share the moment are her mum Daphne and space engineer husband Daniel Tighe.
Speaking about the thrill of pushing forward the frontiers of exploration, she says: "If you think about how hard it was to reach the North Pole on Earth, it took a lot of effort to get there. There were terrible conditions and a lot of people died to achieve that.
"We've never seen the poles of the Sun, we don't know what there is there. The poles are one of the last pieces of the puzzle.
"We'll be able to see what is behind the Sun as well. There are many places in our solar system that are not explored yet."
Professor Harra admits that, like many of us, she acquired her passion for space exploration much closer to home.
"One of the things that encouraged me was a trip to Armagh Planetarium as a child," she says. "When I've been to the planetarium recently and seen all the kids running around really excited, that was me.
"But when I was at school I didn't know that you could get jobs in space and I wasn't planning for it. Going to university I did maths and physics. With maths and physics, you can do anything, and I didn't have a clear plan until I did my PhD.
"I didn't plan to be in this career, I guess. I didn't really know what you could do in space. It's good for children to understand that if you're building a spacecraft there are so many skills required.
"It's a huge, broad range of skills, different types of engineering, different physics, and management of those things requires particular skills, to manage a big team. It's not just the image of scientists that sit in a corner on their own; people are communicating together, software people, mechanical people, electronics people."
Since completing her degree at Queen's University Belfast Professor Harra's career has firmly focused on solar research. Her first job on leaving university was with the Yohkoh Japanese space mission and she went on to work in England on the follow-up to that mission, before moving to Davos in Switzerland last year to work on the Solar Orbiter.
"All the missions I've worked on have studied the Sun. Yohkoh was already launched two years when I joined. I worked on the operation of spacecraft, did the science for that and began to plan for a follow-up mission. The mission was in the Earth's orbit," she says.
"The follow-up mission was Hinode, which means Sunrise in Japanese. The tradition in Japan is that once the mission has launched and completed one successful orbit, it's christened like a child; the Japanese children named it. It's still operating and it's a teenager now, it's 14 years old this year."
Most recently she's moved to Davos in Switzerland where she has been working on the Solar Orbiter programme at PMOD/WRC.
"It's a European Space Agency mission, which has been worked on for the last 20 years, from the concept through the development of technology to allow us to get as close to the Sun as we will do," Professor Harra explains.
"On Sunday night we're launching the spacecraft from Cape Canaveral and our teams have been meeting here all this week to plan out what we do in the period just after launch and to finalise things.
We're going to a place where no spacecraft has been and we're looking down at the Sun in a way that we've never been able to do before. It's really a discovery area because we've never been able to do it beforeProfessor Louise Harra
"The purpose of the mission is to get up close to the Sun, to be able to see and touch the Sun and observe what is happening on the Sun's surface and what leaves the Sun as the solar wind flows past us."
One mystery scientists hope to solve is why the surface temperature of the Sun is 5,500 degrees while the temperature of its enveloping corona - the layer of searingly hot plasma gas that begins about 2,000km off the solar surface and extends for millions of kilometres into space - is thought to be two million degrees.
There are other questions scientists hope to be able to answer too. For example, part of the work will analyse the solar wind as it flows past the spacecraft: "The Sun has a storm which produces things like the Northern Lights but it can have more damaging effects on things like spacecraft and the electricity grid, and it can affect long haul flights over the Poles, which may have to be diverted," she explains. Flights over our Poles may have to be diverted when the solar wind is in evidence, because of the danger of high radiation and the disruption it causes to the aircraft's communication links, she explains.
"Planes have to be in communication all the time and a solar stream can disrupt that communication to the aircraft," she says.
"So there are a number of things that can happen that can have economic impacts on Earth."
Following this weekend's launch it will take around two years for the Solar Orbiter to reach its orbit around the Sun, around the same distance out as the planet Mercury, which is the closest planet to the Sun.
"One of the things that was needed was a shield on the front of the spacecraft that will protect it, and the material that was developed for that was developed by a company in Dublin called Enbio," Professor Harra says.
"The orbit has a close point and a far point. Staying in that orbit takes about 150 days and then we will slowly change the orbit so that the spacecraft can look down at the poles of the Sun.
"We're going to a place where no spacecraft has been and we're looking down at the Sun in a way that we've never been able to do before. It's really a discovery area because we've never been able to do it before.
"We have a certain plan for seven years, but it will depend on the health of the spacecraft and the instruments after that whether it will be prolonged. We can't predict what will happen because nothing has ever been in this orbit before."
Professor Harra is involved in the teams managing two of the 10 instruments installed on the Solar Orbiter.
"The first one is the imager that will be imaging high energy wave bands such as UV," she says.
"If you look out of the window, the Sun looks quite bland from the Earth, just a wide, yellow disc. But if you look at it in a different wavelength you can see how dynamic the Sun is. It's constantly changing and our images will be used to see that up close.
"The other instrument is the spectrometer which measures what the Sun is composed of, and also things like temperature. It's like a thermometer but it also measures what's there as well.
"This is one of the reasons why we want to get in so close. When you want to understand the storms, Earth is quite a distance away from the Sun and the storms have travelled quite a distance to get to us. They change a lot in that time, so we want to get in close to see what is happening.
"It's a very tough environment because of the heat extremes. You're going from a very hot to a very cold environment. You are also in that environment where you've got a lot of energetic particles coming from the Sun and they hit the spacecraft as well. Part of the technology design was to be able to cope with that.
"The solar particles can damage the electronics and can also degrade the solar panels, they are quite nasty things. It's a difficult environment."
Coincidentally, there are two graduates of Queen's University on the same instrument team: Professor Harra and her European Space Agency colleague, physicist David Williams.
At the team meetings you can feel the nervousness in the people for the launch. The atmosphere is quite fizzy. People will be emotional because it's been over such a long time. All these grown men have been getting quite emotional about itProfessor Louise Harra
"Each instrument team is about 20 people, then there's the spacecraft operations side, which is probably another 20 or 30 people, and then around the world the number of people working on it goes into thousands," she says. While Professor Harra has worked on a number of space missions, this is the first time she has attended a launch.
"It will be exciting; scary but exciting," she says. "The launch would have been on Wednesday, in fact, but it was delayed twice in the last week due to various issues that have come up.
"When they're doing a launch outside of the Earth orbit, they do what they call a wet dress rehearsal. They have the rocket in place, then they go through all the countdown procedures and during that there was a problem. Then, when they rescheduled, it was too windy - you can't hoist things in place in strong winds.
"Because this is a one-off spacecraft, nothing's ever been there before. We've had delays, we've encountered problems in the development and design. It's the way it is when you've never done something before, there are initial problems that have to be dealt with.
"At the team meetings you can feel the nervousness in the people for the launch. The atmosphere is quite fizzy. People will be emotional because it's been over such a long time. All these grown men have been getting quite emotional about it.
"People have been working over their holiday time, evenings, weekends to get things working and try to fix the problems. It's been 20 years since the concept of the mission was developed and through the technical developments, trying to get selected and approved by ESA, it's a long process."
The launch will take place at 11pm on Sunday and the observers will be bussed out to watch it.
"It's a night launch which will look spectacular," Professor Harra says. "People will just be nervous and excited in equal measure. When I think about it I feel my stomach flip; it's like an exam nervousness. But there is absolutely nothing we can do. I think people will be very emotional."
She's delighted that her husband Daniel and mum Daphne are both there to witness the launch.
"A lot of the people have brought family with them. Yesterday we saw the launch pad from a distance and I could feel my stomach flip. When you know your spacecraft is on top of that huge rocket, it will be a nervous thing to look at!"
She admits the space exploration fraternity is a close-knit community - and indeed that's how she met her husband, who is from Kent.
"We met over a spacecraft," she laughs. "He came to my previous work on the Hinode missions and took a contract working on thermal design, and that is where we met.
"People are pretty social. I think one of the nice things about working on the project is that it takes 10 or 20 years, and you're working with the same people over that period. They are like family as well.
"I had a Japanese colleague and we worked together from when we were graduates and his surname is also Harra. People have always joked that he's my Japanese brother and his children call me Aunt. I still see him two or three times a year at meetings and it's a good opportunity to see these people regularly."
Professor Harra adds: "It's nice to have that long term relationship with people in different places. But your diary is mapped out a couple of years ahead because you know certain things will happen - your life is dominated by a spacecraft!"