Love of Spirals
spiral /sp^ir(ð)l/ a & adv MI6 [Fr., or med.L spiralis, f. L spira SPIRE n. see -AL.] A adj 1Winding continuously round a fixed point at a steadily increasing or decreasing distance in the same plane. M16. 2Forming a continuous curve which winds like the thread of a screw in a cylindrical or conical manner; helical. M16. b Med Of a fracture: curving round a long bone lengthwise. L19.
Observed in nature, in many flowers, spiders webs, sea shells and in the chambers of the Nautilus. Humans have used them in ornament for centuries - for example, Erechtheum, the Ionic temple of Athena, built approx 400BC, Athens.
Perfectly pleasing to our eye
A Golden Rectangle is a rectangle in which the ratio of the length to the width is the Golden Ratio. For example, if one side of a Golden Rectangle is 2 metres long, the other side will be approximately equal to 2 * (1.62) = 3.24. It is the most pleasing of all rectangles.
If you have a Golden Rectangle and you cut a square off it so that what remains is a rectangle, that remaining rectangle will also be a Golden Rectangle. You can keep cutting these squares off and getting smaller and smaller Golden Rectangles. Drawing a line through the points, as shown, will give you a spiral very like that found in a nautilus shell.
The Golden Ratio
The golden ratio is a special number approximately equal to 1.6180339887498948482. Like Pi, the digits of the Golden Ratio go on forever without repeating.
Our Closest Spiral Galaxy, Andromeda
The galaxy's central bulge glows in the light emitted by warm dust from old, giant stars. Just outside the bulge, a system of inner spiral arms can be seen, and outside this, a well-known prominent ring of star formation.
NASA's Spitzer Space Telescope
This telescope has captured a stunning infrared view of the famous spiral galaxy known as Andromeda. Approximately 2.5 million light-years away, Andromeda is the closest spiral galaxy and is the only one visible to the naked eye.
Spitzer's sensitive infrared eyes have detected captivating new features, including bright, aging stars and a spiral arc in the center of the galaxy. The infrared image also reveals an off-centered ring of star formation and a hole in the galaxy's spiral disk of arms.
Spitzer detects dust heated by stars in the galaxy. Its multiband imaging photometer's 24-micron detector recorded approximately 11,000 separate infrared snapshots over 18 hours to create the new comprehensive mosaic. This instrument's resolution and sensitivity is a vast improvement over previous infrared technologies, enabling scientists to trace the spiral structures within Andromeda to an unprecedented level of detail.
"In contrast to the smooth appearance of Andromeda at optical wavelengths, the Spitzer image reveals a well-defined nuclear bulge and a system of spiral arms," said Dr. Susan Stolovy, a co-investigator from the Spitzer Science Center at the California Institute of Technology, Pasadena.
NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology. The Jet Propulsion Laboratory is a division of Caltech.