ESA Gaia Mission as a Classification Machine for Variability Studies

1 . Variability Tree Extrinsic Intrinsic Asteroids AGN tion ESA Gaia as a Stars Credit : Credit: Eyer et al. (2018) Adapted from: L. Eyer & N. Mowlavi (03/2009) Stars classification machine Eclipse Eclipse Secular rolensing Rotation Eclipse Eruptive Cataclysmic Pulsation Star Variability studies with Postgres-XL PV Tel Photom. Per RCB DY Per Asteroid occultation ZAND BLAP UG V361 Hya Planetary transits Eclipsing binary FKCOM V1093 Her L SN BY Dra UV Ceti N PG 1159 SR WR ELL ZZ Ceti SARV OSARG LBV Krzysztof Nienartowicz ACYG V777 Her RS CVn SXA on behalf of FU Solar-like RV GCAS ACV SPBe Gaia Data Processing Centre in Geneva RR CW CEP and Coordination Unit GDOR 7 Hot OB Supergiants PMS δ Scuti BCEP roAp SPB DST SXPHE on behalf of the CU7/DPCG Geneva and international teams Gaia Data Processing and Analysis Consortium 

2 . Databases in Astro-sciences • New wave of Big Data astronomical projects • Sensor data • ESA Gaia 2014-..(1PB x replicated) • ESA Euclid 2021 - (10PB) • JWST 2019-.. (>50TB over 5 years) • LSST Large Sky Survey Telescope 2023-…(60PB-> 20PB DB) • SKA Square Kilometre Array Telescope, 2022-… (300-500PB per year! - 5EB) • CTA Cherenkov Telescope Array (100PB by 2030) • E-ELT, VLT… the list goes on.. 

3 . Gaia: Goal of the mission • 3D cartography of our Milky Way • With additional properties • Motion • Colour (spectra) • Brightness • Variability • Census of the Galaxy (plus quasars, supernovae etc) • Note: Details are complex. y 

4 . Gaia: Goal of the mission • 3D cartography of our Milky Way • With additional properties • Motion Mission of superlatives which results will last • Colour (spectra) for several decades • Brightness • Variability • Census of the Galaxy (plus quasars, supernovae etc) • Note: Details are complex. y 

5 . Mission To understand our Galaxy and its history To describe fundamental properties of stars To calibrate the distances in the Universe To discover binary stars, exo-planets, variable stars, supernovae, black holes, quasars, asteroids, gravitational lenses, etc New phenomena… To constrain the dark matter To be a base for future projects (LSST…) 

6 . Immediate impact • in 2018: 173811 astro-articles published • The main Data Release 2 (05/2018) article had 1237 citations • The most cited 2018 astronomy article! 

7 .Galactic map of stars ~1.7 billion stars 1-2% of the galaxy 

8 .Galactic dust from Gaia 

9 .Evident signature of Sagittarius dwarf galaxy and stream associated with it 

10 .Signature of cataclysmic past at galactic scale With Gaia data, we detect clearly the signature of a galac6c collision with an other galaxy called Enceladus which occurred 10 billion years ago ESA (artist's impression and composition); Koppelman, Villalobos and Helmi 

11 .Discovery of in-bound high speed stars ESA 

12 .Discovery of in-bound high speed stars Search of high speed stars escaping our Galaxy ESA 

13 .Discovery of in-bound high speed stars Search of high speed stars escaping our Galaxy Surprise: some high speed stars are going towards us ESA 

14 .The Gaia spacecraft 

15 .CCD Camera of 1 billion pixels 

16 .The Gaia instruments i.e. Internet of [Space] Things 2 off-axis telescopes 1.45 x 0.5 m2 aperture basic angle = 106.5° 35 m focal length 10 mirrors Edge processing! common focal Krzysztof Nienartowicz Gaia DPAC, PgCon, Ottawa, 2014/05 6 plane, 106 CCDs (1 Gigapixel) 0.93 x 0.42 m2 !13 

17 . Gaia mission: Time-series machine = 10um arcsec seen on the Moon • Launched in December 2013 • 1.5 million km to travel to L2 orbit (19 days) • + calibration took half a year • Official data taking started on 25th July 2014 • 5-6.7 microarcseconds positions of bright stars • Proper motions to 3.5 uarcsec • 5Mbs downlink 

18 . Gaia mission: Time-series machine = 10um arcsec seen on the Moon • Launched in December 2013 • 1.5 million km to travel to L2 orbit (19 days) • + calibration took half a year • Official data taking started on 25th July 2014 • 5-6.7 microarcseconds positions of bright stars • Proper motions to 3.5 uarcsec • 5Mbs downlink 

19 . Scanning law • L2 

20 . Scanning law • L2 

21 .CCD single source traversal B. Holl 

22 .CCD single source traversal B. Holl 

23 .CCD single source traversal B. Holl 

24 . Gaia mission: Time-series machine • Intrinsic data problem: scanning law - timeseries sparsity 

25 . Gaia mission: Time-series machine • Intrinsic data problem: scanning law - timeseries sparsity 

26 .The Gaia Consortium Data Processing centres ObsGE/ISDC involvement Common Language: Java SVN repository Issue tracker: Jira Livelink: document archive Wiki 

27 .Gaia Data Processing Consortium 

28 .Gaia Data Processing Consortium CU1 System architecture CU9 Archive DPCE (ESAC) MDB 

29 .Gaia Data Processing Consortium CU1 System architecture CU9 Archive DPCE (ESAC) MDB DPCT (Torino) CU3 Initial Data Treatment DPCB First Look Intermediate Data Update (Barcelona) CU2 Simulations