At the Center of the Milk Way
Explanation:
At the center of our
Milky
Way Galaxy lies a black hole with
over 2 million times the mass of the Sun.
Once a controversial claim, this
astounding conclusion
is now virtually inescapable and based on observations of
stars orbiting
very near the galactic center.
Using one of the
Paranal
Observatory's
very large telescopes
and a sophisticated infrared camera,
astronomers
patiently followed the orbit of a particular star,
designated S2, as it came within about
17
light-hours of the center of the Milky Way
(about 3 times the radius of Pluto's orbit).
Their results
convincingly show that S2 is moving
under the influence of the enormous gravity of an
unseen object that must be extremely compact -- a
supermassive black hole.
This deep near-infrared
image shows the crowded inner 2
light-years of the Milky Way with the exact position of the
galactic center indicated by arrows.
The ability to track stars so close to the
galactic center
can accurately
measure the black hole's mass and perhaps
even provide an unprecedented test of Einstein's
theory of gravity
as astronomers watch a star
orbit a
supermassive black hole.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
