The Vertical Magnetic Field of NGC 5775
Explanation:
How far do magnetic fields extend up and out of spiral galaxies?
For decades astronomers knew only that some
spiral galaxies had
magnetic fields.
However, after
NRAO's Very Large Array
(
VLA)
radio telescope
(popularized in the
movie Contact)
was
upgraded in 2011, it was
unexpectedly discovered
that these fields could
extend vertically away from the disk by several thousand
light-years.
The featured image of
edge-on spiral galaxy
NGC 5775,
observed in the CHANG-ES
(Continuum Halos in
Nearby Galaxies) survey, also reveals spurs of magnetic field lines that
may be common in spirals.
Analogous to
iron filings around a bar magnet,
radiation from electrons trace
galactic magnetic field lines by
spiraling around these lines at almost the
speed of light.
The filaments in this image are
constructed
from those tracks in VLA data.
The visible light image,
constructed from
Hubble Space Telescope data, shows pink gaseous regions where
stars are born.
It seems that
winds from these regions help
form the magnificently
extended galactic magnetic fields.
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.
