Before, I was a postdoc in the Department of Astronomy at Caltech working with Judy Cohen on tidal streams and the Galactic halo.
I'm interested a lot in the dynamical history of our Milky Way - especially halo formation and the disruption of globular clusters and satellites - , which can tell us a lot about galaxy evolution in general.
As part of my research, I'm developing methods for handling large time-domain survey datasets. I developed astrostatistical and machine-learning methods for fast and reliable detection and classification of variable sources in general, including RR Lyrae and QSOs. Most of my research is based on the Pan-STARRS survey and a subsequent spectroscopically follow-up survey conducted with Keck and Magellan telescopes (The Caltech/Carnegie Survey of the Outer Halo of the Milky Way). For current research, see my publication list.
I'm part of the iPTF/ZTF project and Euclid consortium.
Previously I was a PhD student at Max Planck Institut für Astronomie in Heidelberg, Germany (MPIA), working with Prof. Hans-Walter Rix, Eddie Schlafly and Branimir Sesar. During this time, I was a fellow of the International Max Planck Research School (IMPRS).
contact info
nina [dot] hernitschek [at] vanderbilt [dot] edu
techfreaq [at] web [dot] de
Education
since 2/2017: Postdoc at Caltech
09/2013 to 1/2017: PhD student at MPIA, "Astrophysical Modeling of Time-Domain Surveys", supervisor Hans-Walter Rix
08/2013: M.Sc. Physics, University of Heidelberg, "Estimating Black Hole Masses in Hundreds of Quasars", supervisor Hans-Walter Rix
02/2012: B.Sc. Physics, University of Heidelberg, "Geodesic Lines in Schwarzschild and Kerr Metric", supervisor Matthias Bartelmann
since 2003: worked in several IT projects in industry and research
08/2003: completed 3-year vocational training Fachinformatiker (IHK) (IT specialist, software developer)
Research Assistant
03/2011 - 05/2011: Max-Planck-Institut für medizinische Forschung, Heidelberg: Data analysis
02/2010 - 04/2010: Heidelberg Collaboratory for Image Processing, Universität Heidelberg: software developer for advanced driver assistance systems, robotics
08/2008 - 12/2008: Astronomisches Recheninstitut, Heidelberg: software developer for Gaia
Talks and Conferences
RRL/Cep 2019 - Frontiers of Classical Pulsators: Theory and Observations, October 13 - 18 2019, Cloudcroft, New Mexico, US http://rrl2019.nmsu.edu SOC, machine-learning workshop
Annual Keck Science Meeting, September 19 - 20 2019, UCLA, Los Angeles, US https://conferences.pa.ucla.edu/keck-2019/
Hot-Wiring the Transient Universe, August 19 - 22 2019, Northwestern University, Evanston (IL), US, talk http://hotwireduniverse.org/
2019 Santa Cruz Galaxy Workshop, August 5 - 9 2019, UCSC, Santa Cruz, US http://hipacc.ucsc.edu/GalaxyWorkshop2019.html
Astroinformatics 2019, June 24 - 27 2019, Caltech Pasadena http://astroinformatics2019.org/
LSST Community Broker Workshop, June 19 - 21 2019, Seattle (WA), US, talk https://project.lsst.org/meetings/cbw/main
NRC Herzberg colloquium talk, Victoria (BC), 6. Nov. 2018
UBC Astronomy colloquium talk, The University of British Columbia, Vancouver (BC), 5. Nov. 2018
Keck Science Meeting, September 20 - 21 2018, Caltech Pasadena, talk http://www.astro.caltech.edu/ksm2018/?utm_source=Keck+Newsletter&utm_campaign=734fe70835-EMAIL_CAMPAIGN_2018_05_11&utm_medium=email&utm_term=0_5a29392474-734fe70835-48147693
The First Caltech-Swinburne Data Science Workshop, September 18 - 19 2018, Caltech http://www.astro.caltech.edu/workshop/
Caltech AI4Science Workshop, August 1 2018, Caltech https://sites.google.com/view/ai-for-science-workshop/
ZTF Summer School 2018, July 18 - 20 2018, Caltech http://www.ztf.caltech.edu/page/ztfss18agenda
The Second Information Universe Conference, July 3 - 6 2018, Groningen, The Netherlands, talk www.informationuniverse.rug.nl talk streaming
Astrophysical Frontiers in the Next Decade and Beyond: Planets, Galaxies, Black holes & the Transient Universe, June 26 - 29 2018, Portland, Oregon, http://www.cvent.com/events/astrophysical-frontiers-in-the-next-decade-and-beyond-planets-galaxies-black-holes-the-transient-uni/event-summary-bc556bd6b79e4ac1be7db2a2177f1725.aspx
Euclid Consortium Meeting, June 11 - 14 2018, Bonn, Germany https://euclid2018.astro.uni-bonn.de/
Statistical Challenges in 21st Century Cosmology, May 22-25 2018, Valencia, Spain, talk http://cosmo21.cosmostat.org/
SnowPAC 2018: Big Questions, Big Surveys, Big Data: Astronomy & Cosmology in the 2020s, March 11-16 2018, Snowbird, Utah, US, talk http://www.physics.utah.edu/snowpac/
Piercing the Galactic Darkness, October 16-19 2017, Heidelberg, Germany http://www2.mpia-hd.mpg.de/galdark2017/
The RR Lyrae 2017 Conference. Revival of the classical pulsators: from galactic structure to stellar interior diagnostics, September 17-21 2017, Niepolomice, Poland, talk https://www.rrl2017.pl/presentations/talk_Hernitschek.pdf http://www.rrl2017.pl
The 3rd Swinburne-Caltech Workshop: Galaxies and their Halos, September 11-12 2017, Caltech, talk http://astronomy.swin.edu.au/research/conferences/swincaltw3/home.html
Euclid Consortium Meeting "100 years of Lambda", June 5–8 2017, London http://euclid2017.london/
Building the Infrastructure for Time-Domain Alert Science in the LSST Era, May 22-25, Tucson, AZ, USA https://www.noao.edu/meetings/lsst-tds/
ZTF Galactic science workshop, March 13-14 March 2017, Caltech
IAU Symposium 325 on Astroinformatics, October 20-24 2016, Sorrento, Italy; award for best poster presentation
IMPRS Summer School "Astrostatistics & Data Mining", September 12-16 2016, Heidelberg, Germany
ESO Munich Joint Conference "Discs in Galaxies", July 11-15 2016, Garching, Germany https://www.eso.org/sci/meetings/2016/Discs2016.html
LSST@Europe2 Conference, June 20-24 2016, Belgrade, Serbia, invited talk https://project.lsst.org/meetings/lsst-europe-2016/
Heidelberg Physics Graduate Days, April 11-15 2016, Heidelberg http://gsfp.physi.uni-heidelberg.de/graddays
RR Lyrae 2015 Conference "High-precision studies of RR Lyrae stars from dynamical phenomena to mapping the galactic structure", 19-22 October 2015, Visegrad, Hungary, invited talk http://rrl2015.hu/
Astro Hack Week 2015, September 28 - October 02, 2015, New York University http://astrohackweek.github.io/
A 3D View on Galaxy Evolution: from Statistics to Physics, July 6-10 2015, MPIA Heidelberg, Germany http://www2.mpia-hd.mpg.de/~galsp2015/
The Local Group Astrostatistics Conference: Bridging Observations & Simulations, MIRA, University of Michigan, June 1 - 4 2015, talk https://www.lsa.umich.edu/mira/workshopsconferences/localgroupastrostatistics
GC Group Retreat, April 21-23 2015, talk
IMPRS seminar retreat, March 2-4 2015, talk
8th HGSFP Winterschool 2015, University Center Obergurgl, January 31 - February 4 2015, poster presentation poster_variability_hernitschek.pdf
2014 Gaia Challenge, Heidelberg, October 27-31 2014
Science Results from Pan-STARRS1, Space Telescope Science Institute Baltimore, June 23-26, talk https://webcast.stsci.edu/webcast/detail.xhtml?talkid=4150&parent=1
Summer Schools in Statistics & Informatics for Astronomers, Penn State University, June 2-13 2014
The Multi-Wavelength, Multi-Epoch Heritage of Stripe 82, Princeton University, March 2014, poster presentation poster_revmap_hernitschek.pdf
The Galaxy, Stellar Compositions and Dynamics, GREAT-ITN School, IAC (Tenerife, Spain), August 2013
Publications
P. Capak, D. Sconlic, J-C. Cuillandre, F. Castander, A. Bolton, R. Bowler, C. Chang, A. Dey, T. Eifler, D. Eisenstein, C. Grillmair, P. Gris, N. Hernitschek, et al., Mini-survey of the northern sky to Dec <+30, LSST Survey White Paper Submitted in Dec 2018 [arXiv:1904.10438 [astro-ph.IM]]
R. A. Arnold, M. V. McSwain, J. Pepper, N. Hernitschek et. al., Long-Period High-Amplitude Red Variables in the KELT Survey, ApJ 247, 2 (2020) [AJ] [arXiv:2001.06498 [astro-ph.SR]]
D. D. Whitten, T. C. Beers, V. M. Placco, R. M. Santucci, P. Denisenkov, P. B. Tissera, N. Hernitschek, Constraints on inner halo assembly history from identification of blue horizontal-branch age gradient and break radius in the inner halo, ApJ 884, 1 (2019) [AJ] [arXiv:1909.12910 [astro-ph.GA]
D. C. Masters, D. K. Stern, J. G. Cohen, P. L. Capak, S. A. Standord, N. Hernitschek et al., The complete calibration of the color-redshift relation (C3R2) survey: updates, analysis, and Data Release 2, (2019) ApJ accepted [arXiv:1904.06394 [astro-ph.GA]]
N. Hernitschek, J. G. Cohen, H.-W. Rix et al., Precision distances to dwarf galaxies and globular clusters from Pan-STARRS1 3π RR Lyrae, ApJ 871, 1 (2019) [AJ] [arXiv:1811.10808 [astro-ph.GA]]
M. A. Fardal, R. P. van der Marel, D. R. Law, S. T. Sohn, B. Sesar, N. Hernitschek, H.-W. Rix, Connecting the Milky Way potential profile to the orbital timescales and spatial structure of the Sagittarius Stream (2018), MNRAS sccepted [arXiv:1804.04995 [astro-ph.GA]]
N. Hernitschek, J. G. Cohen, H.-W. Rix et al., The Profile of the Galactic Halo from Pan-STARRS1 3π RR Lyrae, ApJ 859, 31 (2018) [ApJ] [arXiv:1801.10260 [astro-ph.GA]]
N. Hernitschek, B. Sesar, H.-W. Rix et al., The Geometry of Sagittarius Stream from Pan-STARRS1 3π RR Lyrae, ApJ 850, 96 (2017) [AJ] [arXiv:1710.09436 [astro-ph.GA]]
B. Sesar, N. Hernitschek, M. I. P. Dierickx et al., The > 100 kpc KPC Distant Spur of the Sagittarius Stream and the Outer Virgo Overdensity, as seen in PS1 RR Lyrae stars, AJ 844, L4 (2017) [AJ] [arXiv:1706.10187]
B. Sesar, N. Hernitschek, S. Mitrović, Z. Ivezić et al., Machine-Learned Identification of RR Lyrae Stars from Sparse, Multi-band Data: the PS1 Sample, AJ 153, 5 (2017) [AJ] [arXiv:1611.08596]
N. Hernitschek, H.-W. Rix, E. F. Schlafly, B. Sesar, D. Hogg, Z. Ivezić et al., Finding, characterizing and classifying variable sources in multi-epoch sky surveys: QSOs and RR Lyrae in PS1 3π data, ApJ 817, 73 (2016) [ApJ] [ADS][arXiv/1511.05527]
N. Hernitschek, H.-W. Rix, J. Bovy, & E. Morganson, Estimating Black Hole Masses in Hundreds of Quasars, ApJ 801, 45 (2015) [ApJ] [ADS][arXiv/1412.6531]
N. Hernitschek, E. Schmidt, M. Vollmer, Lunar eclipse photometry: absolute luminance measurements and modeling, Appl. Optics 47, 62 (2008) [ADS]
Conference Proceedings
N. Hernitschek, B. Sesar, H.-W. Rix, J. G. Cohen (2018), The Geometry of Sagittarius Stream from Pan-STARRS1 3π RR Lyrae In Radek Smolec, Karen Kinemuchi, Richard Anderson (Eds.), The RR Lyrae 2017 Conference. Revival of the Classical Pulsators: from Galactic Structure to Stellar Interior Diagnostics, Proceedings of the Polish Astronomical Society, vol. 6, pp. 72-76 https://www.pta.edu.pl/proc/v6p72
N. Hernitschek, E. F. Schlafly, B. Sesar et al. (2016), Finding, characterizing and classifying variable sources in multi-epoch sky surveys: QSOs and RR Lyraes in PS1 3π In L. Szabados, R. Szabo, K. Kinemuchi (Eds.), RRL2015 High-Precision Studies of RR Lyrae Stars No. 105 COMMUNICATIONS FROM THE KONKOLY OBSERVATORY OF THE HUNGARIAN ACADEMY OF SCIENCES (pp. 85-92) http://www.konkoly.hu/Mitteilungen/Mitt105/105.pdf
N. Hernitschek, E. F. Schlafly, B. Sesar et al. (2016), Pan-STARRS1 as pilot-survey for panoptic time-domain science. Proceedings of the International Astronomical Union, 12(S325), (pp. 118-121). doi:10.1017/S1743921316012667 https://www.cambridge.org/core/journals/proceedings-of-the-international-astronomical-union/issue/E992FC19B0DD8B57AA4FC2F6B58E3FA6
Teaching
supervising undergraduate student 2018 supervising undergraduate studen 2014 Astrolab 02/2014 - 03/2014
Observing
For The Caltech/Carnegie Survey of the Outer Halo of the Milky Way, I regularly observe with MIKE at Magellan (LCO) and ESI at Keck.
For the Euclid project, I regularly observe with ESI and MOSFIRE at Keck to take spectra for photo-z calibration.