#CJam, 8 bytes

l:i2fbS*

Easy-peasy:

l:i           "Read the input line and convert each character to its ASCII value";
   2fb        "Put 2 on stack and use that to convert each ASCII value to base 2";
      S*      "Join the binary numbers by space";

Try it here

CJam, 8 bytes

l:i2fbS*

Easy-peasy:

l:i           "Read the input line and convert each character to its ASCII value";
   2fb        "Put 2 on stack and use that to convert each ASCII value to base 2";
      S*      "Join the binary numbers by space";

Try it here