---------------------------------- Hubble 5 ----------------------------------
Hubble 5 is a strikingly lovely "butterfly" or bipolar (two-lobed) nebula
which has received relatively little attention. Internal motions in the
nebula have been measured spectroscopically to be in excess of 200 miles
per second. The heat generated by the winds causes the each of the lobes
to expand, much like a pair of balloons with internal heaters. The
expanding lobes encounter older material ejected previously. Supersonic
shocks form where the ambient gas is compressed and heated ahead of the
rapidly expanding lobes. Atoms caught in the shocks radiate the visible
light seen in this image.
Image Factoids for Hubble 5
Nickname: Hubble's Double Bubble
observed by HST: Sep 9 1997
distance 0.7 kpc (2200 l.y.)
constellation: Sagittarius
HST instrument: WFPC2 (2 orbits) with filters F631N (neutral oxygen, shown
in red), F658N (once-ionized nitrogen, shown in green), F502N
(twice-ionized hydrogen, shown in blue)
Credits for the image of Hubble 5
Bruce Balick, University of Washingto
Vincent Icke, Leiden University (The Netherlands)
Garrelt Mellema, Stockholm University
NASA