title: Pandas - convert strings to time without date
body: <p>I've read loads of SO answers but can't find a clear solution.</p>
  
  <p>I have this data in a df called <code>day1</code> which represents hours:</p>
  
  <pre><code>1    10:53
  2    12:17
  3    14:46
  4    16:36
  5    18:39
  6    20:31
  7    22:28
  Name: time, dtype: object&gt;
  </code></pre>
  
  <p>I want to convert it into a time format. But when I do this:</p>
  
  <p><code>day1.time = pd.to_datetime(day1.time, format='H%:M%')</code></p>
  
  <p>The result includes today's date:</p>
  
  <pre><code>1   2015-09-03 10:53:00
  2   2015-09-03 12:17:00
  3   2015-09-03 14:46:00
  4   2015-09-03 16:36:00
  5   2015-09-03 18:39:00
  6   2015-09-03 20:31:00
  7   2015-09-03 22:28:00
  Name: time, dtype: datetime64[ns]&gt;
  </code></pre>
  
  <p>It seems the <code>format</code> argument isn't working - how do I get the time as shown here without the date?</p>
  
  <hr>
  
  <p><strong>Update</strong></p>
  
  <p>The following formats the time correctly, but somehow the column is still an object type. Why doesn't it convert to <code>datetime64</code>?</p>
  
  <p><code>day1['time'] = pd.to_datetime(day1['time'], format='%H:%M').dt.time</code></p>
  
  <pre><code>1    10:53:00
  2    12:17:00
  3    14:46:00
  4    16:36:00
  5    18:39:00
  6    20:31:00
  7    22:28:00
  Name: time, dtype: object&gt;
  </code></pre>