ROOM
84
Space Environment
S
tars light the Universe and provide the
chemical elements which are the keys to all
life as we know it. Stars also link apparently
disparate branches of physics, from the
microscopic quantum world to cosmological
general relativity. Binary stars are particularly
crucial to our understanding of the Universe on all
these scales. They are an indispensable tool for
measuring the masses of stars, as discovered by
Kepler and Newton in the 17th century. Their orbital
properties, such as period and eccentricity (the
shape of its orbit), derive directly from fundamental
physical properties of matter, i.e. its mass and
angular momentum - which is a measure of spin.
There is a population of stars that, despite their impact in the field, have
remained under the radar for too long: binary stars. Perhaps not favoured as
much as other astronomical head-line grabbing phenomenon, these double-
star systems have a lot to offer. Whatever their size, binary stars of all kinds
play an important role in the circle of galactic life, proving that without their
existence, stellar life could otherwise be a bit dull in the Universe.
ESA/Foster
Binary stars and their
extraordinary lives
Robert G. Izzard
Institute of
Astronomy, University
of Cambridge, UK
Orsola De Marco
Macquarie University,
in Sydney, Australia
Depiction of the strange
object of AR Scorpii. In this
unique double star, a
rapidly spinning white
dwarf star (right) powers
electrons up to almost the
speed of light. These high
energy particles release
blasts of radiation that
impact the companion red
dwarf star (left) and cause
the entire system to pulse
every 1.97 minutes with
radiation ranging from the
ultraviolet to radio.
