#04: Gaia Phased Array Antenna delivered and integrated 06 Jul
2012 10:38 The phased array antenna that Gaia will use to send
its science data to Earth has been delivered and integrated onto
the Service Module. The antenna provides the high gain and data
rate needed to allow large volumes of data to be transmitted
over the 1.5 million kilometres that will separate the
spacecraft's operational orbit from Earth. The use of electronic
beam steering allows the signal to be directed towards Earth as
the spacecraft rotates; a conventional, mechanically pointed
antenna would cause microvibrations, seriously impacting the
performance of the telescope. High data rate The Gaia mission
will perform astrometric measurements on over one billion
objects in the Milky Way and its Local Group. To do this, the
spacecraft will spend five years in a Lissajous orbit around the
second Lagrange point of the Sun-Earth system (L2), which is
located 1.5 million km from Earth in the anti-Sun direction.
Gaia will generate an enormous vo