He may have the right stuff, but he got the wrong digits.

Timothy Peake, a former British Army Air Corps officer and current European Space Agency astronaut aboard the International Space Station, phoned home to a wrong number on Thursday.

After failing to connect, he took his flub to Twitter, posting: “I’d like to apologise to the lady I just called by mistake saying ‘Hello, is this planet Earth?’ - not a prank call...just a wrong number!”

It was not clear if the person who answered understood how long-distance the call actually was.

Responding to Mr. Peake’s tweet, one Twitter user wanted to know what the space station’s area code was. But even without that, Earthlings can connect with the station: Its amateur radio frequencies are publicly available, and anyone with the proper equipment and the required radio license can try to call when it passes 250 miles above.

Mr. Peake, 43, should probably be forgiven for his lack of mastery of ship-to-shore dialing, because he is a recent arrival to the International Space Station. He is the first publicly funded British astronaut, and his voyage to the space station on Dec. 15 was closely watched in Britain, where cost-conscious governments have generally avoided supporting human spaceflight. His job during his six-month mission is running science experiments, he has said on his blog, and in his spare time, he is training for the London Marathon.