Related topics: galaxies · stars · black holes · nasa · astronomers

Observations explore radio jet of a powerful quasar

European astronomers have conducted very long baseline interferometric (VLBI) observations of a radio jet structure in a powerful quasar known as PKS 2215+020. The collected VLBI data provide important insights into the properties ...

Pandora's Cluster explored by researchers

Using the Magellan Telescopes in Chile, Italian astronomers have observed a giant galaxy cluster known as Abell 2744, dubbed the Pandora's Cluster. Results of the observational campaign, presented in a paper published February ...

Astronomers discover new supernova remnant

Astronomers from Curtin University in Australia and elsewhere report the detection of a new supernova remnant (SNR) located some 3,300 light years away. The newfound SNR, designated G321.3-3.9, has an elliptical shape and ...

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A light-year or light year (symbol: ly) is a unit of length, equal to just under 1013 kilometres. As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in a vacuum in one Julian year.

The light-year is often used to measure distances to stars and other distances on a galactic scale, especially in non-specialist and popular science publications. The preferred unit in astrometry is the parsec, because it can be more easily derived from, and compared with, observational data. The parsec is defined as the distance at which an object will appear to move one arcsecond of parallax when the observer moves one astronomical unit perpendicular to the line of sight to the observer, and is equal to approximately 3.26 light-years.

The related unit of the light-month, roughly one-twelfth of a light-year, is also used occasionally for approximate measures.

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