Credit & Copyright: Data -
Hubble
Heritage Project,
Unwinding - Paul
Howell
Explanation:
The arms of a grand design spiral galaxy 60,000 light-years across are
unwound in this digital transformation of the magnificent 2005
Hubble
Space Telescope portrait of M51.
In fact, M51 is one of the original spiral nebulae, its winding
arms described by a mathematical curve known as a
logarithmic
spiral, a spiral whose separation grows in a
geometric
way with increasing distance from the center.
Applying logarithms to shift the pixel
coordinates in the Hubble image relative to the center of M51 maps
the galaxy's spiral arms into diagonal straight lines.
The transformed image dramatically shows the arms themselves are
traced by star formation, lined with pinkish starforming
regions and young blue star clusters.
Companion galaxy NGC 5195 (top) seems to alter the track of the arm in
front of it though, and itself remains relatively unaffected by this
unwinding of M51.
Also known as the
spira mirabilis,
logarthimic spirals can be found in nature on all scales.
For example, logarithmic spirals can also describe
hurricanes,
the tracks of subatomic particles
in a bubble
chamber and, of course,
cauliflower.
January February March April May June July August September October November December |
|
NASA Web Site Statements, Warnings, and Disclaimers
NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.
Based on Astronomy Picture
Of the Day
Publications with keywords: M 51 - spiral galaxy
Publications with words: M 51 - spiral galaxy
See also: