Bob McDonald is now flying through space, between Mars and Jupiter.

That's right. A kilometre-wide asteroid has been named after CBC's Bob McDonald.

McDonald hosts CBC Radio's weekly science show Quirks & Quarks, writes a blog for CBCNews.ca and is the national science commentator for CBC-TV, where he often uses low-tech props such as coffee cups to explain complicated concepts about astronomy.

He has already won lots of awards for the work he's done to communicate science to the public, including the Order of Canada, and learned of this latest honour while sailing around Vancouver Island during his vacation.

"I almost fell overboard," he recalled in an interview Tuesday. "It's huge for me. As a little kid, I dreamed about going into space, being out there. That hasn't quite happened yet, so having an object named after me is almost as good."

Bob McDonald is the host of CBC's Quirks & Quarks and the national science commentator for CBC-TV. (CBC)

The asteroid was discovered in 2006 by David Balam, a professional observer at the National Research Council of Canada and the University of Victoria, using the Canada-France-Hawaii Telescope.

While surveying part of the sky for supernovas, he also tracked debris closer to Earth in the same area.

"It's like watching a school of fish in a way," he said.

The newly named space rock, which went by the number 332324 and the designation 2006 XN67, didn't get its official moniker until two weeks ago.

According to astronomical tradition, the person who discovers an asteroid can suggest a name, which becomes official when it is sanctioned by the Committee on Small Body Nomenclature of the International Astronomical Union. Balam has so far discovered and named about four dozen space rocks, and has also had an asteroid named after himself.

He said he usually names new asteroids for Canadian astronomers, science educators and people who popularize astronomy. In this case, he said, he couldn't think of anyone more deserving of the honour than McDonald for his work popularizing astronomy and science in general in Canada.

Generally, Balam prefers to break the news to his asteroids' namesakes in person, surprising them with a framed certificate and sometimes an asteroid-shaped cake.

"I call it 'rocking' them," he said with a laugh, adding that asteroid cakes are not hard to make since the space rocks have pretty irregular shapes.

However, he said, given the internet it's hard to keep a secret, so he had to send McDonald an email before the news spread.

The asteroid has now been added to a list of 432 asteroids with Canadian connections, maintained by the Royal Astronomical Society of Canada.

Among those added to the list with asteroid Bob McDonald was asteroid Glenn Hawley, named after the society's most recent past president. It too was discovered by Balam, in 2003, and named by him.