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

Astronomers inspect two galactic open clusters

Using the Tubitak National Observatory (TUG) and ESA's Gaia satellite, Turkish astronomers have inspected Berkeley 68 and Stock 20—two galactic open clusters. Results of the study, presented November 17 on the arXiv pre-print ...

Study investigates a rare Type Icn supernova

An international team of astronomers has conducted optical and near-infrared observations of a rare Type Icn supernova known as SN 2022ann. The results of the study, published November 9 on the preprint server arXiv, shed ...

An ultra-short-period exoplanet discovered with TESS

Using NASA's Transiting Exoplanet Survey Satellite (TESS), an international team of astronomers has detected a new ultra-short-period exoplanet. The newfound alien world, designated HD 20329 b, orbits its host star in slightly ...

Astronomers detect new Jupiter-like exoplanet

Using radial velocity measurements, astronomers from Japan and China have detected a new exoplanet orbiting a G-type giant star. The newfound alien world is similar in mass to Jupiter but much hotter than the solar system's ...

New eclipsing binary discovered with TESS

Using NASA's Transiting Exoplanet Survey Satellite (TESS), astronomers have detected a new low-mass, pre-main-sequence binary system. The newfound binary, designated 2M1222−57, contains two stars the size of the sun but ...

Changing-look events observed in the galaxy NGC 5273

Astronomers have analyzed new and archival multiwavelength observations of the active galaxy NGC 5273. As a result, they detected so-called "changing-look" events in the active galactic nucleus of this galaxy. The finding ...

Type II supernova SN 2020jfo investigated in detail

An international team of researchers have performed high-cadence photometric and spectroscopic observations of a Type II supernova known as SN 2020jfo. Results of the observational campaign, presented November 5 on arXiv.org, ...

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Light-year

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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