Agency astronaut is currently on board the International Space Station, zipping around Earth in orbit. On Friday, Peake went out on a spacewalk along with NASA astronaut Tim Kopra on a mission to repair a power unit outside the station. Peake took a selfie to commemorate the event.Peake is the first British ESA astronaut on the ISS and the first astronaut to wear a British flag during a spacewalk. The flag patch was attached to the left shoulder of his spacesuit. Astronaut Michael Foale was born in Britain and conducted a spacewalk back in 1995, but did so under the US flag as a NASA astronaut.The close-up selfie shows Peake`s shoulders and helmet with the blackness of space behind him. The Earth is reflected as a blue globe in his visor. But that`s not all. Take a close look and you will see part of the station, Peake`s hands, the camera and his fellow astronaut Kopra in the distance. That`s quite a lot to pack into a selfie."Today`s exhilarating #spacewalk will be etched in my memory forever - quite an incredible feeling!" Peake tweeted in regards to his space adventure.Peake and Kopra successfully replaced the faulty unit ahead of schedule. Peake`s photo op joins an illustrious lineup of space selfies that includes a snap of astronaut Barry "Butch" Wilmore during a spacewalk in 2015 and a historic self-portrait taken by Buzz Aldrin in 1966 during the Gemini 12 mission.Peake has plenty on his plate during his time in space. He will run a marathon timed to match the London Marathon back on Earth on April 24. The astronaut will strap into a specialized treadmill for the athletic feat. Perhaps we`ll get another space selfie during Peake`s challenging run. -CNET