Receiving 401 "Bad Credentials" when hitting github API endpoint

I'm trying to build a CLI that uses the GitHub api. I instantly run into a road block. Although I've read the introductory docs up and down, I don't see what is wrong in the following code.

var userData = require('../userData');
var request = require('request');

module.exports = {
  authorize: function() {
    var username = "<redacted_user_name>",
        password = "<redacted_password>",
        auth = "Basic " + new Buffer(username + ":" + password).toString("base64");

    var options = {
      method: 'get',
      url: " https://api.github.com/<redacted_user_name>",
      headers: {
        "Authorization": "auth",
        "User-Agent": "<redacted_whatever_doesnt_matter>"
      }
    }
    request(options, function (error, response, body) {
      console.log('error:', error); // Print the error if one occurred
      console.log('statusCode:', response && response.statusCode); // Print the response status code if a response was received
      console.log('body:', body); // Print the HTML for the Google homepage.
    });

  },
}

prints:

error: null

statusCode: 401

body: {"message":"Bad >credentials","documentation_url":"https://developer.github.com/v3"}

via Alex Bollbach