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Patterns and templates are curiously powerful things. From fossils that resemble nothing more than a stone version of a PCB, to similar patterning between a meteor and earth magnetite bacteria, to the astutely observed details of a statue that can imply recovery of a long lost catalogue, the devil is indeed in the detail.

Atlas hefts the stars Silence is gold Louisiana State University Associate Mobiles look like picking up on a silent $20bn, Professor, physics and astronomy, Bradley the world market value currently put on some Schaefer, has discovered that a long-lost 120bn minutes of one-way phone calls that star catalogue of Hipparchus (c.129 BC) cannot be answered by their recipients. appears on the Roman Farnese Atlas statue. Israeli company Silent Communications aims The great astronomer's catalogue was lost, to fill that silence using ‘Talking without Talk- possibly in the Alexandria library fire. ing’ (TWiT) and will sell its technology to both The C2nd Atlas is a seven-feet tall marble fig- mobile phone vendors and the operators. ure, carrying a 26” diameter sky globe embel- Responses are made to the caller using a lished, with 41 Greek constellations, as well as list of pre-recorded messages, which can be the celestial equator, tropics and ecliptic. Top: Modern magnetotactic bacteria, one show- customised for a wide range of situations. ing a chain of magnetite crystals, as seen in the Schaefer says several facts led to his conclu- No-talking calls can even be initiated with a backscattered scanning electron microscope. sion that the statue’s sky globe was based pre-recorded enquiry and then listening to Bottom: Magnetite crystals and chains of mag- on Hipparchus' catalogue. First Hipparchus’ the answer. netite crystals in the Martian meteorite ALH84001 `Procession’ (finding that stars and constella- in the backscattered scanning electron micro- tions move slowly with respect to the celes- Superparamagnetic scope. One conspicuous chain indicated by arrows. The diameter of a single crystal is tial equator) provides a major key to dating A compass needle, under half the size of approximately one-millionth of an inch. the original observations. Schaefer meas- the previously smallest-known compasses, Photo: NASA ured a total of 70 positions on the globe which occur naturally in magnetotactic bac- and made a formal mathematical fit, finding teria that orient themselves using the earth's Dream on the best date at 125 BC. geomagnetic field, has been made by Just one cellular pathway, located inside the researchers from the University of California same part of a cell where photosynthesis The constellation figure positioning has an at Davis, who have built needles at occurs, produces the raw ingredients plants accuracy of 3.5o unachievable in writing or 20x200nm. use to make thousands of compounds, from verbally (only accurate to 8o). Star catalogues molecules with anticancer properties, to the alone would have the required accuracy. And The researchers' nanocompass could be active ingredient in catnip, according to a Hipparchus is the only known star catalogue used to measure magnetic fields at the team of researchers at Purdue University & created at the correct time of 129 BC. nanoscale, and to orient nano wires during Max Planck Institute for Chemical Ecology. Ptolemy's version came too late in AD 128. the building of molecular-sized structures. The finding challenges long-held assumptions The researchers strung together particles of on how plants produce commercially impor- magnetite on nano wires made from lithium tant products, and has implications for molybdenum selenide. Each magnetite parti- researchers trying to harness plant pathways cle is as small as 7nm in diameter. Needles to produce essential oils, used as flavour are superparamagnetic at room tempera- additives in food and medicine, or as ture, meaning they don't have the bacteria’s fragrance, says lead researcher, Professor of compass sensitivity to the earth’s extremely horticulture, Natalia Dudareva. weak magnetic field. Expect two to five years before the magnetic compass can be No such manufacturing pathway yet for Farnese Atlas statue carries the missing star map used in advanced devices. III-Vs nano compounds.

48 III-Vs REVIEW THE ADVANCED SEMICONDUCTOR MAGAZINE VOL 18 - NO 1 - FEBRUARY 2005