Canadian astronaut Chris Hadfield is to become a tourism ambassador for Ireland.
The former International Space Station commander, who became an internet sensation after recording his own version of David Bowie's Space Oddity while in space, has agreed to promote the country to his millions of fans around the world.
"Having seen Ireland from space, it's great to be able to give Chris Hadfield a closer look at what Ireland has to offer on the ground," Mr Varadkar said.
"His enthusiasm and energy make him a great ambassador for Irish tourism, and should help to persuade many more to come and see Ireland close-up in 2014. I'm really delighted he has agreed to help us out."
Commander Hadfield's visit coincides with the release of new figures from Failte Ireland, which revealed the country's tourism sector is on the up.
In its annual tourism industry review, the organisation reported that seven out of 10 hotels expect further growth in business this year.
It also found that numbers employed increased almost 12% last year, and that tourism employment should increase further by 6,000 to 8,000 in 2014.
Commander Hadfield and his wife Helen will spend their trip like tourists, visiting Croke Park and the Guinness Storehouse in the capital.
Tourism Ireland has convinced him to appear in three short films documenting his visit, which will feature different attractions like Gaelic games and the country's famous scenery.
In Dublin, he is to visit the BT Young Scientist and Technology Exhibition, and give a talk at the Laya Healthcare Pendulum Summit.
His itinerary also includes Donegal and the Inishowen Peninsula, the starting point of the Wild Atlantic Way.
Commander Hadfield, whose daughter is a student at Trinity College Dublin, has a known love for Ireland and has visited before.
He tweeted to his Twitter followers last year in Irish, saying: "Ta Eire fioralainn! Land of green hills and dark beer. With Dublin glowing in the Irish night."
He has also promised to tweet about what he sees and experiences during his current visit, which it is hoped will encourage his more than one million followers to plan their own holiday to Ireland.
Tourism Ireland chief executive Niall Gibbons said he was delighted to have Commander Hadfield's support.
"I would like to personally thank him for his tremendous generosity in agreeing to help us promote the island of Ireland around the world," Mr Gibbons said.
"Of course, he already began promoting Ireland last year, with the dramatic photos he tweeted from the International Space Station to his huge Twitter fanbase.
"Chris is an enormously popular, global figure and I am confident that our films of his visit to Ireland will be seen and shared by millions of potential holidaymakers around the world - inspiring them to come and sample the destination for themselves."
The short films featuring commander Hadfield will appear on Tourism Ireland's Facebook page, for the organisation's two million fans across the world to see.