Byr
Byr was formerly used in
English-language geology andastronomy as a unit of one billionyear s. The "B" is an abbreviation for "billion" (meaning thousand million), with "yr" simply an abbreviation for "year". Today, the termgigaannum (Ga) is also used, but Gy or Gyr are still sometimes used in English-language works (at the risk of confusion with the gray). Some scientists use Gyr as an abbreviation for Gigayear.cite journal | url=http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?2007A%26A...476.1373S&db_key=AST&nosetcookie=1 | author=Selsis et al. | title=Habitable planets around the star Gl 581? | journal=Astronomy and Astrophysics | volume=476 | issue=3 | year=2007 | pages =1373 – 1387 | doi=10.1051/0004-6361:20078091] Specifically, one Gyr is equal to 109year s.Because a billion means 1000 million in some countries but can mean a million million in others its use is deprecated in favour of
giga- which unambiguously means 109 andannum which for precision may be qualified by (sidereal ), (Julian), etc.ee also
*
Myr
*annum
*Before Present
* Gigaannum or Ga
*Gya
*mya (unit)
*Orders of magnitude (time)#Years Notes
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Look at other dictionaries:
byr — byr·lady; byr·law; byr·law·man; byr·nie; byr·son·i·ma; … English syllables
Byr — Byr, Robert, Pseudonym, s. Bayer 5) … Meyers Großes Konversations-Lexikon
Byr — Byr, Robert, Pseudonym von K. R. E. von Bayer … Kleines Konversations-Lexikon
BYR — internationaler Währungscode für: Belarus Rubel … Universal-Lexikon
BYR — (Währungscode für Belarus Rubel) … Die deutsche Rechtschreibung
BYR — Rubel Land: Weißrussland Unterteilung: 100 Kapejek ISO 4217 Code: BYR Abkürzung: Br Wechselkurs: (17. März 2009) 1 … Deutsch Wikipedia
BYR — Cette page d’homonymie répertorie les différents sujets et articles partageant un même nom. Sigles d’une seule lettre Sigles de deux lettres > Sigles de trois lettres Sigles de quatre lettres … Wikipédia en Français
BYR — … Википедия
BYR — Books for Young Readers (Community » Educational) * Baruya (Regional » Language Codes (3 Letters)) * Bake Young Realty (Business » Firms) * BackYard Rinks, Ltd. (Business » Firms) * Baytree Real Estate (Business » Firms) * Bring Your Reefers… … Abbreviations dictionary
byr — ISO 639 3 Code of Language ISO 639 2/B Code : ISO 639 2/T Code : ISO 639 1 Code : Scope : Individual Language Type : Living Language Name : Baruya … Names of Languages ISO 639-3
