I had a hard time coming up with just one person who has become a virtual mentor. I follow lots of different people on many different platforms. Anthropologists, scientists, writers, all of whom inform me of various news items and new research. People like Neil DeGrasse Tyson, Bill Nye, Phil Plait, and Elise Andrew all represent science well and provide hours of information in various forms. People like Warren Ellis, Greg Rucka, and Bruce Sterling are writers of various forms that engage in thinking about the future and the weird and everything in between.
The one place I go to everyday though is io9.com. It is a member of the Gawker network of news/gossip blog sites and I have been a member of its community for going on four years now. It is an aggregator site that combines news about science fiction/fantasy entertainment (t.v., movies, comics, novels, etc.) and hard science. They have many contributors and do not relegate themselves to a single point of interest. They post columns throughout the day that regard everything from materials science to anthropology to biology and space news.
What I like most about it is that the hard science news is explained in plain language by writers who are passionate and interested in the material. On top of that the comment section, while having all the usual problems with public forums (though not terrible), is an amazing group of like minded people who will expound on the article. Sometimes this confuses the issue with dissenting opinions, but sometimes these differing viewpoints expand the topic and provide alternate sources.
Combining learning with entertainment is the best way to engage an audience. io9 does this and also satisfies many aspects of my fandom. I can’t see a time when I wont visit the site at least twice a day.