planetary alignment


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planetary alignment

The rough alignment along a solar radius of the outer planets, Jupiter to Neptune, that takes place approximately every 179 years. The most recent planetary alignment took place at the beginning of the 1980s, making possible the two Voyager missions to Jupiter, Saturn, and beyond (see Voyager probes). The planetary alignment was thought to provide the only cost-effective way to visit the outer planets because using Jupiter's gravitational field to accelerate a probe, changing both its velocity and direction, saved fuel and took years off the journey time. But improved mathematical techniques for calculating accurate flightpaths, including gravity assists, mean that space scientists do not necessarily have to wait for planetary alignments to send probes to the outer Solar System. See also gravity assist.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006
References in periodicals archive ?
The waning moon will also serve as a guide for the planetary alignment. On Thursday, the moon will be near Saturn.
APRIL Positive planetary alignments make you want to spread the cheer.
Most believers in the power of planetary alignments forgot the failure of earlier lineups to induce disaster.
The time it takes for Venus to "lap" Earth, from one planetary alignment to the next--that is, to travel 360[degrees] more than Earth--is approximately (360 / 0.6165) [approximately equal to] 583.9 days.
The current planetary alignment helps to increase wealth and influence, so on a personal level this is an excellent month to pursue a career dream, start a new business or form a business partnership.
A MUSEUM has painstakingly reconstructed an 18th century clockwork model of a rare planetary alignment which is set to reoccur later this year, it revealed.
"There seems to be some kind of planetary alignment. All the commodities in vogue happen to be great prospects in Ontario.
August 20 and September 5, 1977 The launches are timed to meet a rare planetary alignment in order to travel the most distance using the least amount of time and energy.
The last such planetary alignment in 1988 brought the election of Carlos Salinas de Gortari in Mexico and George Bush (father of the current U.S.
ONE AMAZING PREDICTION CLAIMS THE "GRAVITATIONAL PULL" FROM A "RARE" PLANETARY ALIGNMENT ON MAY 5, 2000, WILL TUG ON THE SOUTH POLE AND SHIFT EARTH'S AXIS.
And it will probably occur next May 5, due to a planetary alignment.
Either way, for hundreds of years scientists and theologians alike have been perplexed by the origins of the Star of Bethlehem, One of the most recent studies of historical, astronomical and biblical records suggests the event in 6BC was actually a rare planetary alignment, during which the sun, Jupiter, the moon and Saturn all lay in the constellation Aries.