Skip to content
EntityQ648908· pop 6· linked from 59 articles

Also known as b.y.a.

bya or b.y.a. is an abbreviation for "billion years ago". It is commonly used as a unit of time to denote length of time before the present in 109 years. This initialism is often used in the sciences of astronomy, geology, and paleontology.

In the Vinony graph

Vinony's link graph records 59 inbound references to bya, and connects out to year, United States and Europe.

It is catalogued under topics including Chronology, Metrology and Units of time.

Vinony links it to 6 Wikipedia language editions.

Wikidata facts

Instance of
acronym
Show 2 more facts
unit symbol
bya
conversion to standard unit
1000000000

via Wikidata · CC0

~1 min read

Encyclopedic overview

2 sections
Contents
  • See also
  • References

bya or b.y.a. is an abbreviation for "billion years ago". It is commonly used as a unit of time to denote length of time before the present in 109 years. This initialism is often used in the sciences of astronomy, geology, and paleontology.

The "billion" in bya is the 109 "billion" of the short scale of the US, not the long-scale 1012 "billion" of some European usage. Billion by this convention (109) is often called a "thousand million" in the UK and a "milliard" in some other countries. For this reason, there is potential for some confusion, and some scientists prefer the unit Gya, while others prefer Ga (Giga-annum), however, bya remains in more widespread use. In 1974, the UK switched from the long scale to the short scale.

Excerpted from Wikipedia’s “bya” article, available under the CC BY-SA 4.0 licence.

Available in 6 languages

via Wikidata sitelinks · CC0

Connections

Categories