Alex Szalay

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Alex Szalay
Alex Szalay.jpg
Alexander Sandor Szalay

(1949-06-17) June 17, 1949 (age 71)
Alma materUniversity of Debrecen (B.Sc.)
Eötvös Loránd University(M.Sc., Ph.D.)
Known forSloan Digital Sky Survey
National Virtual Observatory
WorldWide Telescope
AwardsBloomberg Distinguished Professorships (2015)
Jim Gray eScience Award (2007)
Széchenyi Prize (1991)
Scientific career
Computer Science
Big data
WebsiteOfficial website

Alex Szalay is a Bloomberg Distinguished Professor[1] of Physics and Astronomy[2] and Computer Science[3] at the Johns Hopkins University School of Arts and Sciences and Whiting School of Engineering.[4] Szalay is an international leader in astronomy, cosmology, the science of big data, and data‐intensive computing.


Alexander Sándor Szalay, Jr. was born in Hungary. His father is Sándor Szalay, who is considered “the father of nuclear physics in Hungary” for his discovery of a natural enrichment mechanism of uranium and neutrinos.[5] Szalay graduated with a Bachelor of Science degree in Physics in 1969 from Kossuth University, now University of Debrecen, in Hungary. He then received a Master of Science in Theoretical Physics 1972 and a Ph.D in Astrophysics in 1975 from the Eötvös Loránd University in Budapest.[6] During this period, from 1974–1982, Szalay also played guitar in the Hungarian rock band Panta Rhei (band).[7] After graduation Szalay spent postdoctoral periods at the University of California, Berkeley, University of Chicago, and Fermilab, before accepting an assistant professorship at Eötvös Loránd University in 1982. After rising to the rank of full professor at Eötvös, he joined Johns Hopkins University in 1989. Subsequently, he was named the Alumni Centennial Chair in 1998 and earned a secondary appointment in the Department of Computer Science in 2001. In 2008, he became Doctor Honoris Causa of the Eötvös Loránd University.

In March 2015, Szalay was named a Bloomberg Distinguished Professor at Johns Hopkins University for his accomplishments as an interdisciplinary researcher and excellence in teaching.[8][9] The Bloomberg Distinguished Professorship program was established in 2013 by a gift from Michael Bloomberg.[10][11] Szalay holds joint appointments in the Johns Hopkins University Zanvyl Krieger School of Arts and Sciences’s Department of Physics and Astronomy[12] and the Whiting School of Engineering’s Department of Computer Science.[13] Through the Bloomberg Distinguished Professorship, Szalay also will be teaching a new undergraduate class in data science, using a synthesis of statistics, computer science, and basic sciences that he thinks “will become the fundamental language used by the next generation of scientists.”[4]

Since 2009, Szalay has been the founding director of the Institute for Data Intensive Engineering and Science (IDIES) at Johns Hopkins, an interdisciplinary institute fostering “education and research in applying data-intensive technologies to problems of national interest in physical and biological sciences and engineering.” At the time of its founding, IDIES was the “first interdisciplinary big data center of its type […] and has since inspired similar efforts at other universities.”[14] IDIES is supported by the National Science Foundation, NASA, Intel, Microsoft, Nokia, Nvidia, the Gordon and Betty Moore Foundation, and the W. M. Keck Foundation.[15]

Awards and Distinctions[edit]

In 1990, Szalay was elected to the Hungarian Academy of Sciences as a Corresponding Member and awarded the E.W. Fullam Prize of the Dudley Observatory.[16] The following year, he received Hungary's Széchenyi Prize, which recognizes “those who have made an outstanding contribution to academic life in Hungary.”[17] Szalay was recognized in particular for his “discovery of the large scale (400 million light years) distribution pattern of galaxies.”[5] In 2003, he was elected as a Fellow of the American Academy of Arts and Sciences. In 2004, he received an Alexander Von Humboldt Research Award in Physical Sciences. In 2007, Szalay received the Jim Gray eScience Award in recognition for his “foundational contributions to interdisciplinary advances in the field of astronomy and groundbreaking work with Jim Gray.”[18] The IEEE Computer Society awarded Szalay with the 2015 Sidney Fernbach Award for "his outstanding contributions to the development of data-intensive computing systems and on the application of such systems in many scientific areas including astrophysics, turbulence, and genomics.”[19]


Szalay is an astrophysicist who has made significant contribution to our understanding of the structure formation and on the nature of the dark matter in the universe. Distinguished in the area of the cosmology, he works on the statistical measures of the spatial distribution of galaxies and galaxy formation. He has contributed much to the field of theoretical astrophysics and large scale structure. Szalay has developed several novel statistical techniques about optimal estimators for galaxy correlations, power spectra, photometric redshifts for galaxies, optimal co-adding of multicolor images, PCA-based spectral classification of galaxies and Bayesian techniques applied to spatial cross-matching of different astronomical catalogs. He has also led the development of data-intensive computer architectures covering all aspects of this process from design to implementation.

Particular accomplishments include:

Sloan Digital Sky Survey[edit]

Professor Szalay is the Architect for the Science Archive and Chair of the Science Council of the Sloan Digital Sky Survey, the most used astronomy facility in the world today.[20] He collaborated with Jim Gray to design an efficient system to perform data mining on the SDSS Terabyte sized archive, based on innovative spatial indexing techniques, that represented a “thousand-fold increase in the total amount of data that astronomers have collected to date.”[21] The SDSS Science Archive has attracted an unprecedented number of users, and is considered to be an example for online archives of the future. Currently, he is on the Science Advisory Council of the Large Synoptic Survey Telescope.

A minor planet discovered by the Sloan Digital Sky Survey at Apache Point Observatory was named 170010 Szalay in his honor.[22]

Virtual Observatory & Cosmological Simulations[edit]

Szalay is a leader in the grass-roots standardization effort to bring the next generation petascale databases in astronomy to a common basis, so that they will be interoperable. In support of this goal, Szalay was Project Director of the National Virtual Observatory.[23] In 2001, Jim Gray and Szalay wrote up a viewpoint article on the national virtual observatory project for Science, entitled "The World-Wide Telescope."[24] He was also one of the founders of the International Virtual Observatory Alliance and part of the core team to build the Galaxy Zoo,[25][26] one of the most visible citizen science projects today.

Szalay collaborated with Simon White and Gerard Lemson to build a database similar to the SkyServer out of the Millennium Simulation, which became the reference cosmology simulation used by astronomers all over the world.[27] In collaboration with Piero Madau, he is building the 1.2PB database, known as The Milky Way Laboratory, for the Silver River cosmology simulation, currently running at Oak Ridge National Laboratory.[28]

Data-intensive Computing[edit]

Dr. Szalay was involved in the early projects related to the Computational Grid, in particular the GriPhyN and iVDGL projects, creating testbed applications for high energy physics and astrophysics. He has collaborated on high-speed data analytics for more than a decade, and has been part of the TeraFlow project[29] since 2004 [30] and the Open Science Grid.[31] He was also heavily involved in the Data Conservancy, researching the long-term curation and preservation of scientific data.[32]

He has coauthored several papers with Gordon Bell, one of the world's premier computer designers, arguing how Amdahl's law can be used to revisit data-intensive computing architectures from first principles.[33][34] Applying these ideas, he built a low power system, GrayWulf, using Atom processors with extremely good IO performance per unit power (factor of 15 better than a typical rack server).[35] GrayWulf was named in homage to and builds on the work of Szalay's collaborator legendary Microsoft computer scientist Jim Gray and Beowulf, the “original computer cluster developed at NASA using ‘off-the-shelf’ computer hardware.”[14] Szalay led the team that won the Supercomputing Data Challenge in SC-08 - the International Conference for High Performance Computing, Networking, Storage and Analysis - with their entry "Storage Challenge GrayWulf: Scalable Clustered Architecture for Data-Intensive Computing."[36][37] In 2010, Szalay began developing the Data-Scope, a 6.5PB system with 500Gbytes/s sequential throughput, utilizing a uniquely balanced system built out of hard disks, SSDs and GPUs, for maximal data flow across the system.[38][39] The Data-Scope went online in 2013 and read “data 30 times faster than GrayWulf, making it the fastest data-processing system at any university in the world.”[14]

Szalay has more recently branched out in other scientific areas focusing on data-intensive computing.[40] In collaboration with Randal Burns, Charles Meneveau, and Greg Eyink, he has built the 350TB turbulence database (JHTDB) providing immersive access to a large computational fluid dynamics simulation, where users can launch virtual sensors into the simulation that report back their velocity. A landmark paper using these resources appeared in Nature.[41]

With Andreas Terzis and Katalin Szlavecz, he has built an end-to‐end wireless sensor system for in-situ monitoring of environmental parameters, including CO2, and measuring the impact of the soil on the global carbon cycle.[42] With sensors around Baltimore, Brazil, Ecuador and the Atacama Desert in Chile, the system has more than 200,000 sensor days of data and several hundred million data points.[43]

Szalay has also become heavily involved in applying modern data-intensive computational techniques to genomics, in collaboration with Steven Salzberg, Ben Langmead, Sarah Wheelan, and Richard Wilton. The collaboration has built a new alignment system for genomics, which is substantially faster than any other system today.[44]


He has written over 575 papers in various scientific journals, covering areas from theoretical cosmology to observational astronomy, spatial statistics and computer science, and more recently turbulence, environmental science and genomics. Szalay has more than 63,805 citations in Google Scholar and an h-index of 96.[45]

He was among the top 1% most cited in the world for subject field and year of publication in the 2001 and 2014 Thomson Reuters Highly Cited Researchers reports.[46]

  • 1998, Large Scale Structures of the Universe (International Astronomical Union Symposia). with co-editors Jean Audouze & Marie-Christine Pelletan, Springer.[47]
Highly Cited Articles (more than 1300 citations)[45]
  • 2009, with KN Abazajian, JK Adelman-McCarthy, MA Agüeros, SS Allam, and CA Prieto, The seventh data release of the Sloan Digital Sky Survey, in: The Astrophysical Journal Supplement Series. Vol. 182, nº 2, 543.
  • 2007, with JK Adelman-McCarthy, MA Agüeros, SS Allam, KSJ Anderson et al., The fifth data release of the Sloan Digital Sky Survey, in: The Astrophysical Journal Supplement Series. Vol. 172, nº 2; 634.
  • 2006, with M Tegmark, DJ Eisenstein, MA Strauss, DH Weinberg, MR Blanton, et al. Cosmological constraints from the SDSS luminous red galaxies, in: Physical Review D. Vol. 74, nº 12; 123507.
  • 2005, with DJ Eisenstein, I Zehavi, DW Hogg, R Scoccimarro, and MR Blanton, Detection of the baryon acoustic peak in the large-scale correlation function of SDSS luminous red galaxies, in: The Astrophysical Journal. Vol. 633, nº 2; 560.
  • 2004, with M Tegmark, MA Strauss, MR Blanton, K Abazajian, S Dodelson, et el. Cosmological parameters from SDSS and WMAP, in: Physical Review D. Vol. 69, nº 10.
  • 2002, with C Stoughton, RH Lupton, M Bernardi, MR Blanton, S Burles, FJ Castander, et al., Sloan digital sky survey: early data release, in: The Astronomical Journal. Vol. 123, nº 1; 485.
  • 2002, with MA Strauss, DH Weinberg, RH Lupton, VK Narayanan, J Annis, et al. Spectroscopic target selection in the Sloan Digital Sky Survey: the main galaxy sample, in: The Astronomical Journal. Vol. 124, nº 3; 1810.
  • 2000, with DG York, J Adelman, JE Anderson Jr, SF Anderson, J Annis, NA Bahcall, et al., The sloan digital sky survey: Technical summary, in: The Astronomical Journal. Vol. 120, nº 3; 1579.
  • 1993, with Stephen D Landy, Bias and variance of angular correlation functions, in: The Astrophysical Journal. Vol. 412; 64-71.
  • 1986, with JM Bardeen, JR Bond, and N Kaiser, The statistics of peaks of Gaussian random fields, in: The Astrophysical Journal. Vol. 304; 15-61.

See also[edit]


  1. ^ "Bloomberg Distinguished Professorships".
  2. ^ "Alexander Szalay Faculty Page".
  3. ^ "Alexander Szalay Faculty Page, Department of Computer Science".
  4. ^ a b Brooks, Kelly "Johns Hopkins names four new Bloomberg Distinguished Professors", JHU Hub, Baltimore, 30 March 2015. Retrieved on 27 July 2015.
  5. ^ a b Simon, Andrew (1998). Made in Hungary: Hungarian Contributions to Universal Culture. USA: Simon Publications LLC. p. 213. ISBN 978-0966573428. Retrieved 27 July 2015.
  6. ^ "Alexander Sandor Szalay CV" (PDF).
  7. ^ "Panta Rhei". Archived from the original on 2015-08-01. Retrieved 29 July 2015.
  8. ^ "Michael R. Bloomberg commits $350 million to Johns Hopkins for transformational academic initiative". 2013-01-26.
  9. ^ Anderson, Nick. "Bloomberg pledges $350 million to Johns Hopkins University", The Washington Post, Washington, D.C., 23 January 2013. Retrieved on 12 March 2015.
  10. ^ Barbaro, Michael. "$1.1 Billion in Thanks From Bloomberg to Johns Hopkins", The New York Times, New York, 26 January 2013. Retrieved on 1 March 2015.
  11. ^ "Michael R. Bloomberg Commits $350 Million to Johns Hopkins for Transformational Academic Initiative 2013".
  12. ^ "Alexander S. Szalay".
  13. ^ "Johns Hopkins Department of Computer Science - Alex Szalay".
  14. ^ a b c Popkin, Gabriel (Summer 2013). "The Next Scientific Revolution: Big Data". Johns Hopkins University. Retrieved 28 July 2015.
  15. ^ "IDIES".
  16. ^ "CIFAR Program Members - Alexander S. Szalay". Archived from the original on 2015-10-01. Retrieved 2015-07-29.
  17. ^ "Széchenyi Prizes of 2014". 2014-03-20.
  18. ^ "Jim Gray eScience Award".
  19. ^ "2015 Sidney Fernbach Award Recipient". Retrieved 2015-09-30.
  20. ^ Szalay, Alexander; Gray, Jim (2000). "The Sloan Digital Sky Survey and its Archive". ASP Conference Series. 216: 1–10. arXiv:astro-ph/9912382. Bibcode:2000ASPC..216..405S.
  21. ^ "Special Issue of Computing in Science and Engineering Dedicated to the SDSS Science Archive". Retrieved 28 July 2015.
  22. ^ "170010 Szalay (2002 TJ341)". Retrieved 28 July 2015.
  23. ^ "History of the Virtual Astronomical Observatory". Retrieved 28 July 2015.
  24. ^ Szalay, Alexander; Gray, Jim (14 September 2001). "The World-Wide Telescope" (PDF). Science. American Association for the Advancement of Science. 293 (5537): 2037–2040. Bibcode:2001Sci...293.2037S. doi:10.1126/science.293.5537.2037. PMID 11557879. Retrieved 27 July 2015.
  25. ^ C.J. Lintott; K. Schawinski; A. Slosar; K. Land; S. Bamford; D. Thomas; M. Jordan Raddick; R.C. Nichol; et al. (2008). "Galaxy Zoo: morphologies derived from visual inspection of galaxies from the Sloan Digital Sky Survey". MNRAS. 389 (3): 1179–1189. arXiv:0804.4483. Bibcode:2008MNRAS.389.1179L. doi:10.1111/j.1365-2966.2008.13689.x. S2CID 15279243.
  26. ^ C. Lintott; K. Schawinski; S. Bamford; A. Slosar; K. Land; D. Thomas; E. Edmondson; K. Masters; et al. (2011). "Galaxy Zoo 1: data release of morphological classifications for nearly 900,000 galaxies". MNRAS. 410 (1): 166–178. arXiv:1007.3265. Bibcode:2011MNRAS.410..166L. doi:10.1111/j.1365-2966.2010.17432.x. S2CID 56460191.
  27. ^ "From SDSS to Simulations: Data Intensive Astrophysics" (PDF). Retrieved 28 July 2015.
  28. ^ "Presentation at CERN: Data Analysis and Access in Astrophysics" (PDF). Retrieved 28 July 2015.
  29. ^ "Teraflow Testbed: High Performance Flows for Large Distributed Data Archives". Retrieved 28 July 2015.
  30. ^ Szalay, Alexander; Grossman, Robert. "SCI: II: The TeraFlow Project: High Performance Flows for Mining Large Distributed Data Archives". Grantome. Retrieved 28 July 2015.
  31. ^ Zarriello, Dean; Terzis, Andreas; Bagger, Jonathan; Robbins, Mark; Szalay, Alexander. "100G Connectivity for Data-Intensive Computing at JHU". Grantome. Retrieved 28 July 2015.
  32. ^ "The Data Conservancy's partners provide the building blocks for addressing data curation needs". Archived from the original on 13 August 2015. Retrieved 28 July 2015.
  33. ^ Szalay, Alexander; Bell, Gordon (5 January 2009). "Graywulf: Scalable clustered architecture for data intensive computing". System Sciences, 2009. HICSS '09. 42nd Hawaii International Conference on. IEEE: 1–10. doi:10.1109/HICSS.2009.234. ISBN 978-0-7695-3450-3. S2CID 7837424.
  34. ^ Szalay, Alexander; Bell, Gordon (12 March 2010). "Low-power amdahl-balanced blades for data intensive computing". ACM SIGOPS Operating Systems Review. ACM. 44 (1): 71–75. CiteSeerX doi:10.1145/1740390.1740407. S2CID 2511908.
  35. ^ "GrayWulf Takes Byte Out of Data Overload". Microsoft. 2009. Retrieved 28 July 2015.
  36. ^ "SC Challenge Awards". Retrieved 27 July 2015.
  37. ^ "SC Conference - Activity Details – Award Finalist/Winner". Retrieved 27 July 2015.
  38. ^ De Nike, Lisa (1 November 2010). "New JHU Computer To Enable Data Analysis Not Possible Today". Johns Hopkins University. Retrieved 28 July 2015.
  39. ^ "MRI: Development of Data-Scope - A Multi-Petabyte Generic Data Analysis Environment for Science". Retrieved 28 July 2015.
  40. ^ Szalay, Alexander; Gray, Jim (23 March 2006). "2020 Computing: Science in an exponential world". Nature. Macmillan Publishers Limited. 440 (7083): 413–414. Bibcode:2006Natur.440..413S. doi:10.1038/440413a. PMID 16554783. S2CID 4360446.
  41. ^ Eyink, Gregory; Vishniac, Ethan; Lalescu, Christian; Aluie, Hussein; Kanov, Kalin; Burger, Kai; Burns, Randal; Meneveau, Charles; Szalay, Alexander (23 May 2013). "Flux-freezing breakdown in high-conductivity magnetohydrodynamic turbulence". Nature. Macmillan Publishers Limited. 497 (7450): 466–469. Bibcode:2013Natur.497..466E. doi:10.1038/nature12128. PMID 23698445. S2CID 205233857.
  42. ^ Terzis, Andreas; Szlavecz, Katalin; Szalay, Alexander (2010). "Wireless sensor networks for soil science". International Journal of Sensor Networks. Inderscience Enterprises Ltd. 7 (1/2): 53–70. doi:10.1504/IJSNet.2010.03185 (inactive 2021-01-16). Retrieved 27 July 2015.CS1 maint: DOI inactive as of January 2021 (link)
  43. ^ Terzis, Andreas; Szlavecz, Katalin; Szalay, Alexander; Gupchap, Jayant (December 2008). "Deploying Advanced Wireless Sensor Networks for Ecological Monitoring". Microsoft EScience Workshop. Microsoft Research. Retrieved 27 July 2015.
  44. ^ Wilton, Richard; Wheelan, Sarah; Szalay, Alexander; Salzberg, Steven; Langmead, Ben; Buvavari, Tamas (3 March 2015). "Arioc: high-throughput read alignment with GPU-accelerated exploration of the seed-and-extend search space". PeerJ Comput. Sci. PeerJ. 3: e808. doi:10.7717/peerj.808. PMC 4358639. PMID 25780763.
  45. ^ a b Google Scholar "Author: A.S. Szalay", Google Scholar, 27 July 2015. Retrieved on 27 July 2015.
  46. ^ "Highly Cited Researchers 2014, Highly Cited Researchers 2001". Retrieved 28 July 2015.
  47. ^ Andouze, Jean; Pelletan, Marie-Christine; Szalay, Alex, eds. (1988). Large Scale Structures of the Universe (International Astronomical Union Symposia) (1st ed.). ISBN 978-9027727428.

External links[edit]