The Magellanic Stream
Illustration Credit:
Dallas Parr
(CSIRO)
Spanning the sky behind the majestic
Clouds of Magellan
is an unusual stream of gas: the Magellanic Stream.
The origin of this gas might hold a clue to
origin and fate of our
Milky Way's
most famous satellite galaxies: the
LMC and the
SMC.
Two leading genesis hypotheses have surfaced:
that the stream was created by gas stripped off these galaxies as
they passed through the halo of our Milky Way,
or that the stream was created by the differential gravitational tug of the Milky Way.
Measurements of slight angular motions by the
Hipparcos satellite have indicated that the
Clouds are leading the Stream.
Now, recent radio measurements have located
fresh gas emerging from the Clouds,
bolstering the later, tidal explanation.
Most probably, in a few hundred million years, the
Magellanic Clouds themselves will fall victim
to this same tidal force.