18/07/2016 Register for the Gaia 2016 Data Release #1 Workshop now
The Gaia 2016 Data Release #1 Workshop, jointly organised by ESA and DPAC, will present the Gaia mission, its data and its usage. Plenary sessions providing general information will be complemented by smaller parallel hands-on sessions and open forums to discuss own projects, results and foster collaboration. The workshop will take place on 2 - 4 November 2016 at ESAC and is open to all astronomers interested in working with Gaia data. For more information and to register, visit the workshop homepage.
14/07/2016 A gift from Gaia to Pluto observers on the 1st anniversary of a historic flyby
It is just a star out of a billion, but it happens to hide behind Pluto on 19 July 2016. The improved Gaia stellar positions in Gaia-DR1 (to be released on 14 September 2016) will be useful for occultation observations. With Pluto these are of particular interest as the details of the fading, when Pluto moves in front of the star, will reveal details about the atmosphere and its possible changes since the flyby of the New Horizons mission 1 year ago (14 July 2015). Observers exactly aligned with the centre of Pluto and the star could record an ephemeral brightness increase due to light focused by the atmosphere of the dwarf planet as if it was a lens. This "central flash", showing up only for a few seconds, provides the most detailed information possible from remote observations, but also requires to accurately know the position of the star and of Pluto. The Gaia position for UCAC4 345-180315 at epoch 2015.0 in the J2000 system is Right Ascension 286.8421576 degrees and Declination -21.1745647 degrees (19h7m22.1178s -21d10’28.433”). With Gaia's position accuracy, which is 1 milliarcsec for this star at epoch 2015.0, the biggest uncertainty of the timing and location of the event as observed from the Earth will be due to uncertainty of the precise Pluto orbit. That too will be tackled by Gaia and published in future data releases.