Gaia DR2 The first real Gaia catalogue Michael Biermann on behalf of the Gaia Data Processing and Analysis Consortium DPAC Michael Biermann Gaia DR2 June 18, 2018 1 / 50
The second Gaia Data Release (Gaia DR2) contains: Gaia DR2 Gaia DR1 Hipparcos total 1690 1140 0,12 positions, parallaxes, proper motions 1330 2 0,12 positions only 360 1140 G magnitudes 1690 1140 0,12 colours (G BP, G RP) 1380 0,12 radial velocitites 7,2 stellar parameters 77 161 }{{} millions quasars 560.000 135.000 3 variable stars 550.000 3.200 12.000 asteroids 14.000 48 22 months of data; reference epoch = 2015.5 Michael Biermann Gaia DR2 June 18, 2018 2 / 50
Magnitude distribution of Gaia DR2 sources Michael Biermann Gaia DR2 June 18, 2018 3 / 50
Magnitude distribution of Gaia DR2 sources Michael Biermann Gaia DR2 June 18, 2018 4 / 50
Magnitude distribution of Gaia DR2 sources Michael Biermann Gaia DR2 June 18, 2018 5 / 50
Magnitude distribution of Gaia DR2 sources Michael Biermann Gaia DR2 June 18, 2018 6 / 50
Magnitude distribution of Gaia DR2 sources Michael Biermann Gaia DR2 June 18, 2018 7 / 50
Magnitude distribution of Gaia DR2 sources Michael Biermann Gaia DR2 June 18, 2018 8 / 50
Magnitude distribution of Gaia DR2 sources Michael Biermann Gaia DR2 June 18, 2018 9 / 50
Magnitude distribution of Gaia DR2 sources Michael Biermann Gaia DR2 June 18, 2018 10 / 50
Magnitude distribution of Gaia DR2 sources: 5p- and 2p-solutions Michael Biermann Gaia DR2 June 18, 2018 11 / 50
Gaia DR2 precisions: parallaxes typical precisions: G magnitude precisions 15 mag 0.03 mas 17 mag 0.1 mas 20 mag 0.7 mas 21 mag 2.0 mas Systematics below 0.1 mas. Michael Biermann Gaia DR2 June 18, 2018 12 / 50
Gaia DR2 precisions: parallaxes Michael Biermann Gaia DR2 June 18, 2018 13 / 50
Gaia DR2 precisions: proper motions Michael Biermann Gaia DR2 June 18, 2018 14 / 50
Gaia DR2 precisions: photometry calibration floors: G BP RP orange magenta G band BP RB 2 mmag 5 mmag 3 mmag DR2 DR1 330 1050 nm 330 680 nm 630 1050 nm Michael Biermann Gaia DR2 June 18, 2018 15 / 50
Gaia DR2 precisions: radial velocities RVS: 845 872 nm; only stars in the temperature range [3550,6900] K Michael Biermann Gaia DR2 June 18, 2018 16 / 50
Source IDs and cross-match: duplicates removed improved accuracy Cycle-01 sources Cycle-02 sources Michael Biermann Gaia DR2 June 18, 2018 17 / 50
Significantly improved angular resolution dense sky areas Pairs in 0:1 arcsec bins 3e4 2e4 1e4 DR2 DR2 w: GBP & GRP DR1 Constant eld density 0 0 1 2 3 4 5 6 Separation [arcsec] Gaia DR1: Gaia DR2: 2 arcseconds 0.4 arcseconds } factor 5! Michael Biermann Gaia DR2 June 18, 2018 18 / 50
Significantly improved angular resolution sparse sky areas Pairs in 0:1 arcsec bins 200 100 DR2 DR2 w: GBP & GRP DR1 Constant eld density 0 0 1 2 3 4 5 6 7 8 9 10 Separation [arcsec] Gaia sees real double stars with 0.4 3 arcseconds separation Michael Biermann Gaia DR2 June 18, 2018 19 / 50
Room for improvements 1 checkered parallax pattern (0.03 mas, in the LMC, but present over all the sky) 0:10 63 64 65 0:08 0:06 Declination [deg] 66 67 68 69 70 71 72 0:04 0:02 0 0:02 0:04 0:06 Median parallax [mas] 73 0:08 100 95 90 85 80 75 70 Right Ascension [deg] 65 60 0:10... 20 spatial patterns of typically 0.02 mas... and a -0.03 mas parallax zero point error Michael Biermann Gaia DR2 June 18, 2018 20 / 50
Gaia DR2 is an independent catalogue! stand alone this time Michael Biermann Gaia DR2 June 18, 2018 21 / 50
Gaia DR2 is an independent catalogue! stand alone this time different photometric system ( G 0.1 mag, colour dependent) Michael Biermann Gaia DR2 June 18, 2018 21 / 50
Gaia DR2 is an independent catalogue! stand alone this time different photometric system ( G 0.1 mag, colour dependent) different source list merged / split / new sources Gaia DR2 Gaia DR1 G < 16: 80-90% of the sources changed sourceid G < 18: 20% of the sources changed sourceid tracking table is delivered as part of Gaia DR2 DR3 outlook: roughly 10% changes to be expected overall Michael Biermann Gaia DR2 June 18, 2018 21 / 50
Gaia-Archive ARI: http://gaia.ari.uni-heidelberg.de/ ESA: http://archives.esac.esa.int/gaia Michael Biermann Gaia DR2 June 18, 2018 22 / 50
Gaia Documentation & Videos we highly recommend to read the Gaia DR2 A&A release papers ( 10 papers) you should also consult the Gaia DR2 on-line documentation http://gaia.esac.esa.int/documentation there are in addition science verification papers with valuable information (A&A, 10 papers) we have videos for scientists explaining important aspects of Gaia DR2 https://www.cosmos.esa.int/web/gaia/guide-to-scientists Gaia User Forum https://www.cosmos.esa.int/web/gaia/forum Michael Biermann Gaia DR2 June 18, 2018 23 / 50
A glimpse of science with Gaia DR2... Michael Biermann Gaia DR2 June 18, 2018 24 / 50
LMC rotational field Michael Biermann Gaia DR2 June 18, 2018 25 / 50
LMC rotational field Michael Biermann Gaia DR2 June 18, 2018 26 / 50
Hertzsprung-Russell diagram Michael Biermann Gaia DR2 June 18, 2018 27 / 50
Hertzsprung-Russell diagram Michael Biermann Gaia DR2 June 18, 2018 28 / 50
Hertzsprung-Russell diagram white dwarfs with H envelope Michael Biermann Gaia DR2 June 18, 2018 29 / 50
Hertzsprung-Russell diagram white dwarfs with He envelope Michael Biermann Gaia DR2 June 18, 2018 30 / 50
Hertzsprung-Russell diagram white dwarfs with C-O core that lost their envelope Michael Biermann Gaia DR2 June 18, 2018 31 / 50
Hertzsprung-Russell diagram binaries with two white dwarfs of equal mass Michael Biermann Gaia DR2 June 18, 2018 32 / 50
Hertzsprung-Russell diagram binaries with a white dwarf and a main-sequence star Michael Biermann Gaia DR2 June 18, 2018 33 / 50
Hertzsprung-Russell diagram unknown population of white dwarfs? Michael Biermann Gaia DR2 June 18, 2018 34 / 50
Hertzsprung-Russell diagram yet unknown population of white dwarfs? Michael Biermann Gaia DR2 June 18, 2018 35 / 50
Hertzsprung-Russell diagram giant branch Michael Biermann Gaia DR2 June 18, 2018 36 / 50
Hertzsprung-Russell diagram HRD of 32 open cluster Michael Biermann Gaia DR2 June 18, 2018 37 / 50
Hertzsprung-Russell diagram HRD of 14 globular cluster Michael Biermann Gaia DR2 June 18, 2018 38 / 50
Hertzsprung-Russell diagram Praesepe and Hyades cluster HRD Michael Biermann Gaia DR2 June 18, 2018 39 / 50
Clean HR diagram of nearby (< 100 pc) stars 5 0 G + 5log 10 ($=100 mas) 5 10 15 20 25 1 0 1 2 3 4 5 6 GBP GRP [mag] ϖ > 10 mas, ϖ/σ ϖ > 10, phot xp mean flux over error > 10: 338,833 Michael Biermann Gaia DR2 June 18, 2018 40 / 50
Clean HR diagram of nearby (< 100 pc) stars 5 0 G + 5log 10 ($=100 mas) 5 10 15 20 25 1 0 1 2 3 4 5 6 GBP GRP [mag] Sources additionally filtered by (magnitude-dependent) chi-square: 249,793 Michael Biermann Gaia DR2 June 18, 2018 41 / 50
Clean HR diagram of nearby (< 100 pc) stars 5 0 G + 5log 10 ($=100 mas) 5 10 15 20 25 1 0 1 2 3 4 5 6 GBP GRP [mag] Sources additionally filtered by chi-square and flux excess ratio: 242,583 Michael Biermann Gaia DR2 June 18, 2018 42 / 50
Stars within 50 pc from the Sun 73,246 Michael Biermann Gaia DR2 June 18, 2018 43 / 50
Stars within 50 pc from the Sun) stars Sources additionally filtered by (magnitude-dependent) chi-square: 39,478 Michael Biermann Gaia DR2 June 18, 2018 44 / 50
Stars within 50 pc from the Sun Sources additionally filtered by chi-square and flux excess ratio: 34,001 (but at least 700 real stars lost) Michael Biermann Gaia DR2 June 18, 2018 45 / 50
Michael Biermann Gaia DR2 June 18, 2018 46 / 50
Michael Biermann Gaia DR2 June 18, 2018 47 / 50
Michael Biermann Gaia DR2 June 18, 2018 48 / 50
On the road to Gaia DR3... Michael Biermann Gaia DR2 June 18, 2018 49 / 50
Forthcoming Gaia DR3 planned for end 2020 photometric epoch data for variable stars double stars 100,000 solar system objects with orbits asteroid spectra more than 1 million quasars and extended objects 35 million radial velocities astrometry, photometry, spectroscopy, variable stars,...: increased numbers, better accuracies/systematics variable stars: more types of variability Michael Biermann Gaia DR2 June 18, 2018 50 / 50