http://sci.esa.int/gaia/56387-gaia-s-first-year-of-scientific-observations/

Last Friday, 21 August, ESA’s billion-star surveyor, Gaia, completed its first year of science observations in its main survey mode.

After launch on 19 December 2013 and a six-month long in-orbit commissioning period, the satellite started routine scientific operations on 25 July 2014. Located at the Lagrange point L2, 1.5 million km from Earth, Gaia surveys stars and many other astronomical objects as it spins, observing circular swathes of the sky. By repeatedly measuring the positions of the stars with extraordinary accuracy, Gaia can tease out their distances and motions through the Milky Way galaxy.

For the first 28 days, Gaia operated in a special scanning mode that sampled great circles on the sky, but always including the ecliptic poles. This meant that the satellite observed the stars in those regions many times, providing an invaluable database for Gaia’s initial calibration. At the end of that phase, on 21 August, Gaia commenced its main survey operation, employing a scanning law designed to achieve the best possible coverage of the whole sky. Since the start of its routine phase, the satellite recorded 272 billion positional or astrometric measurements, 54.4 billion brightness or photometric data points, and 5.4 billion spectra.

The Gaia team have spent a busy year processing and analysing these data
…
Gaia has made an average of roughly 14 measurements of each star on the sky thus far, but this is generally not enough to disentangle the parallax and proper motions. To overcome this, the scientists have combined Gaia data with positions extracted from the Tycho-2 catalogue, based on data taken between 1989 and 1993 by Gaia’s predecessor, the Hipparcos satellite. This restricts the sample to just two million out of the more than one billion that Gaia has observed so far, but yields some useful early insights into the quality of its data.
…
supernova … cataclysmic variable … variable stars … large magellanic cloud … cats eye nebula … spectra … doppler shift … foreground gas … about Gaia … 2016 catalog

mollwollfumble said:

http://sci.esa.int/gaia/56387-gaia-s-first-year-of-scientific-observations/

Last Friday, 21 August, ESA’s billion-star surveyor, Gaia, completed its first year of science observations in its main survey mode.

After launch on 19 December 2013 and a six-month long in-orbit commissioning period, the satellite started routine scientific operations on 25 July 2014. Located at the Lagrange point L2, 1.5 million km from Earth, Gaia surveys stars and many other astronomical objects as it spins, observing circular swathes of the sky. By repeatedly measuring the positions of the stars with extraordinary accuracy, Gaia can tease out their distances and motions through the Milky Way galaxy.

For the first 28 days, Gaia operated in a special scanning mode that sampled great circles on the sky, but always including the ecliptic poles. This meant that the satellite observed the stars in those regions many times, providing an invaluable database for Gaia’s initial calibration. At the end of that phase, on 21 August, Gaia commenced its main survey operation, employing a scanning law designed to achieve the best possible coverage of the whole sky. Since the start of its routine phase, the satellite recorded 272 billion positional or astrometric measurements, 54.4 billion brightness or photometric data points, and 5.4 billion spectra.

The Gaia team have spent a busy year processing and analysing these data
…
Gaia has made an average of roughly 14 measurements of each star on the sky thus far, but this is generally not enough to disentangle the parallax and proper motions. To overcome this, the scientists have combined Gaia data with positions extracted from the Tycho-2 catalogue, based on data taken between 1989 and 1993 by Gaia’s predecessor, the Hipparcos satellite. This restricts the sample to just two million out of the more than one billion that Gaia has observed so far, but yields some useful early insights into the quality of its data.
…
supernova … cataclysmic variable … variable stars … asteroids … large magellanic cloud … cats eye nebula … spectra … doppler shift … foreground gas … about Gaia … 2016 catalog

Other useful Gaia links.
For those like me who like powerpoint slide presentations, this is a year old, registration for the 2015 workshop closes 30 Sep & the workshop is in November in Liverpool: https://www.ast.cam.ac.uk/ioa/wikis/gsawgwiki/index.php/Workshop2014:agenda
The Gaia “science alerts page” – mostly new supernovae but also other unexpected transients. The latest is June 2015, there’s a pause while software is updated before restart in November 2015. http://gaia.ac.uk/selected-gaia-science-alerts/