A cloud of ionized gas emitting light of various colors, often found in regions of active star formation and contributing to the reddish hues observed in galaxies.
Source: esa.int

09/04/2005

21/03/2005

10/03/2005

14/02/2005

25/01/2005

04/01/2005

28/12/2004

08/12/2004

24/10/2004

20/10/2004

06/10/2004

04/10/2004

03/10/2004

21/09/2004

17/09/2004

09/09/2004

19/08/2004

09/08/2004

05/08/2004

07/07/2004

29/06/2004

18/06/2004

20/05/2004

09/05/2004

24/04/2004

08/04/2004

11/02/2004

19/12/2003

24/11/2003

22/10/2003