I subscribe to all of the following and can highly recommend each. They will give you up to date news about astronomy and science in general.
This is an excellent weekly 30 minute podcast run by Fraser Cain (Universe Today) and Dr Pamela Gay (Star Stryder). Each week they cover one topic in detail, you can also look back in the archive and see if there are any past topics you would quite like to listen to.
A monthly hour long podcast from Jodrell Bank covering astronomy news, interviews and questions.
A weekly podcast of about 80 minutes. Absolutely brilliant and highly recommended!
Official podcast of the Skeptic Magazine hosted by Swoopy and Derek giving indepth discussions and interviews.
Podcast hosted by Neil (A really cool dude!). Dig out the interview with Morgan Freeman. Neil was the new host for the remake of Cosmos, which was released in 2014. It was brilliant (only missing Carl and the great Vangelis soundtrack).