-
Across a
Billion Years is a 1969
science fiction novel by
American writer Robert Silverberg. Set in the year 2375, it
follows Tom Rice, a
young archaeologist...
- Five
Billion Years of Change: A
History of the Land (2003, ISBN 157230958X) is a book by
Denis Wood that
attempts a
holistic view of
reality that ranges...
-
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...
- The
Boring Billion,
otherwise known as the Mid
Proterozoic and Earth's
Middle Ages, is the time
period between 1.8 and 0.8
billion years ago (Ga) spanning...
-
contain 100–400
billion stars and at
least that
number of planets. The
Solar System is
located at a
radius of
about 27,000 light-
years (8.3 kpc) from the...
- are
known from at
least 1.65
billion years ago, and a fossil, Grypania,
which may be an alga, is as much as 2.1
billion years old. The "problematic" fossil...
- dwarf,
though its
light is
actually white. It
formed approximately 4.6
billion years ago from the
gravitational collapse of
matter within a
region of a large...
- The
earliest known life
forms on
Earth may be as old as 4.1
billion years old (or Ga)
according to
biologically fractionated graphite inside a single...
- made
between abbreviation "yr" for
years and "ya" for
years ago,
combined with
prefixes for thousand, million, or
billion. In archaeology,
dealing with more...
- The age of
Earth is
estimated to be 4.54 ± 0.05
billion years (4.54 × 109
years ± 1%). This age may
represent the age of Earth's accretion, or core formation...
