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Credit & Copyright: Comparison and M51 image copyright
Brian Lula;
Hurricane Isabel, courtesy
GHCC,
NASA
Explanation:
Uncomfortably close
hurricane Isabel (left)
and 30 million light-year
distant galaxy M51 actually don't have much in common.
For starters, Isabel was hundreds of miles across, while M51 (the
Whirlpool Galaxy)
spans about 50,000 light-years making them vastly
dissimilar in scale, not to mention the extremely different
physical interactions which control their
formation and
evolution.
But they do look amazingly alike, both exhibiting the shape of a simple
and beautiful mathematical curve known as a
logarithmic
spiral, a spiral whose separation grows in a
geometric
way with increasing distance from the center.
Also known as the
equiangular spiral, growth spiral, and Bernoulli's
spiral or spira mirabilis, this curve's
rich properties have fascinated
mathematicians
since its discovery by 17th century philosopher
Descartes.
Intriguingly, this abstract shape is much more abundant in nature
than suggested by the striking visual comparison above.
Logarithmic spirals also describe, for example, the arrangement of
sunflower
seeds, the shapes of nautilus shells, and ...
cauliflower.
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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: hurricane - M 51 - spiral galaxy
Publications with words: hurricane - M 51 - spiral galaxy
See also:
- APOD: 2025 September 4 Á NGC 4565: Galaxy on Edge
- APOD: 2025 August 28 Á Galaxies, Stars, and Dust
- APOD: 2025 August 22 Á A Tale of Two Nebulae
- APOD: 2025 August 19 Á Giant Galaxies in Pavo
- APOD: 2025 August 18 Á NGC 1309: A Useful Spiral Galaxy
- APOD: 2025 July 4 Á NGC 6946 and NGC 6939
- APOD: 2025 June 30 Á NGC 4651: The Umbrella Galaxy