Hubble reveals the central region of the active galaxy M77
(NGC 1068)
M77 is located at a distance of approximately 60 million
light years and is the prototype of a class of galaxies, known as
Seyfert Type 2. In active galaxies, typically the core shines
with the brightness of a billion solar luminosities, and the
brightness of the core fluctuates over the period of a few days
implying that the energy is being released from a region only a
few light-days in extent. The most likely source for this
enormous amount of energy is a “Massive Dark Objects” with a
total mass of 100 million stars like the Sun. Many scientists
believe that these Massive Dark Objects are “super massive”
black-holes.
In the case of M77, previous HST observations (left) have
shown a number of hot gaseous clouds ionized or heated by the
intense radiation from the nuclear source. A torus of “donut” of
opaque dust and gas orbiting the massive central object confines
escaping radiation to a diverging beam or “cone” of emission.
The new FOC/COSTAR observations (right) show with unprecedented
clarity a much more extensive area of emission, produced by
radiation from the active nucleus. An incredible wealth of new
and previously unsuspected filamentary detail is also revealed in
this near-nuclear gas, embedded within the diffuse emission. The
knots and streamers of emission will enable the geometry of this
fascinating nuclear region to be understood, and will offer new
information on the nature of the clouds themselves.
A comparison between the ultraviolet light and the light emission
of the clouds will provide insight into the hidden source of all
the energy – probably a Massive Dark Object, and perhaps an obscured
black-hole.
These data were taken by a team led by Duccio Macchetto of the
European Space Agency (ESA) and Space Telescope Science Institute
(STScI), and including William Sparks and Alessandro Capetti of
STScI, using the Faint Object Camera and COSTAR “combination.”
These images were amoung the first taken with this new equipment
in January 1994.
Last Modification: 20 Jun 1999, 18:40 MET