Stars including Ryan Phillippe, Mia Farrow and Brooklyn Decker were on the edge of their seats on Sunday (23Jun13) as daredevil Nik Wallenda walked a tightrope above a gorge in Arizona on live Tv.

Skywire Live With Nik Wallenda aired in the U.S. on the Discovery Channel, and celebrities took to their pages to share their awe as Wallenda made his way over the Little Colorado River Gorge, near the Grand Canyon, without a safety harness.

Actress/model Decker declared, "My stomach is inside my throat right now... Wow. Wow wow. Amazed/terrified", while Farrow proclaimed, "His poor poor family" and Carrie Underwood asked her fans, "Is anybody else watching this dude walk across the Grand Canyon (sic) on a tightrope? With no net! So crazy!"

Phillippe added, "This is the scariest thing I've ever watched... This is the best advertisement Jesus has had in forever!", while Holly Robinson Peete tweeted, "It's too windy! I can't watch" and actress Kaley Cuoco wrote, "This guy is effing nuts! I wanna throw up!"

Wallenda had viewers gripped for 22 tense minutes, and his famous fans were thrilled when he completed the challenge.

Country star Keith Urban declared, "Go Nik Wallenda! Absolutely astounding feat and faith! We were with you every single step!" and actor Jerry O'Connell added, "Congrats (sic) Nik Wallenda... I'm gonna dig my Shape Ups (shoes) out of the closet now."