Los Angeles, June 24 : 'Two and a Half Men' star Ashton Kutcher has paid a rare tribute to his wife Mila Kunis. The Hollywood actor took to Instagram on Friday to express himself. "I'm the luckiest man alive," the actor captioned his post. "#gratitude." The photo featured Kunis, 39, standing in front of a blue ocean during a tropical getaway with a beautiful mountain range in the background. As per People, she held her arms out wide and stretched towards the sky as a rainbow lined up perfectly behind her. Fans flocked to the comments to gush over the cute couple moment. "Kelso and Jackie FOREVER (sic)", one fan wrote, referencing their respective characters on 'That '70s Show'. Another user said: "What a beautiful picture of a beautiful woman! You're the best couple (in) the world!!!" Kutcher is known for paying tributes to his wife in big ways. Back in February, the actor revealed that he once considered naming a mountain after Kunis after he took a trip to the South Pole to help with his autoimmune condition. "We get to the top and he said: 'You're the first person that has ever climbed this mountain. You get to name it,' " he recalled during an appearance on 'The Late Late Show' with James Corden. "I was like, 'Okay really? It's Mount Mila.' And he says 'No, no, it's bad luck to name it after another person, so don't do that'." /IANS