::: Sitemap Chinese Version中文 PrintPrint Friendly search help
People > Corresponding/Joint/Adjunct Fellow > Curriculum Vita
The spin-rate limit of Jupiter Trojans
First Image from TAOS II Telescopes
Installation of TAOS II Dome
Assembly of TAOS II Dome
Installation of First TAOS II Telescope.
TAOS II enclosures at San Pedro Mártir Observatory
TAOS II Telescope.
TAOS II Enclosure at San Pedro Mártir Observatory
Installation of TAOS II Primary Mirror
TAOS II Primary Mirror Coating
Shadow of a KBO projected onto the surface of the Earth
TAOS II Groundbreaking Ceremony.
Lehner, Matthew
RCUH Research Fellow / Chief Scientist TAOS-2
photo of Lehner, Matthew
Office: Univ. of Pennsylvania
Email: mlehner_replace2@_asiaa.sinica.edu.tw

Education and Positions

  • TAOS II Chief Scientist, ASIAA (2008~present)
  • Research Associate, Harvard College Observatory (2004~2007)
  • Research Associate, University of Pennsylvania (2001~2004)
  • Postdoctoral Research Associate, University of Pennsylvania (2000~2001)
  • Postdoctoral Research Associate, University of Sheffield (1997~2000)
  • Postdoctoral Research Associate, University of California San Diego (1996~1997)
  • Ph.D., Physics and Astronomy, University of California San Diego (1988~1996)
  • B.A., Physics, Washington University, St. Louis, MO (1984~1988)

Research Interests

I am interested in the outer Solar System, particularly the region from the Kuiper Belt out to the Oort Cloud. Kuiper Belt Objects (KBOs) smaller than about 30 km in diameter are practically invisible to direct observational surveys, as are nearly all objects expected to exist beyond 100 AU. I worked on The Taiwanese-American Occultation Survey (TAOS), which searched for occultations of distant stars by small outer Solar System objects. Such events are rare and extremely short in duration, so we monitored a large number of stars (typically 500 stars at any given time) at a high exposure rate (5 Hz). We operated the survey for seven years, and no events were found, allowing us to place the strongest upper limits to date on the surface density of Kuiper Belt objects with diameters between 500 meters and 30 km. Furthermore, we have also found no objects at distances between 100 and 1000 AU, placing the strongest upper limits to date on objects at these distances.

We have nearly completed development of a successor survey, the Transneptunian Automated Occultation Survey (TAOS II), which will be more than a factor of 100 more sensitive than TAOS. The survey is designed to monitor 10,000 stars at a rate of 20 Hz. To achieve this goal, we will use larger telescopes and custom cameras capable of the high readout rate. The three telescopes will are 1.3 m F/4 telescopes with a 2.3 sq. deg. field of view. The cameras will be mosaics of back-illuminated CMOS devices. The telescopes were installed at the San Pedro Mártir Observatory in Baja California, México in the autumn of 2017. The cameras will be delivered in the spring of 2018, and we expect to begin science operations in the summer of 2018.

I am also a member of the Outer Solar System Origins Survey (OSSOS), a large program of the Canada France Hawaii Telescope. The survey has covered 168 sq. deg. with the goal of detecting and classifying over 1,000 KBOs down to a magnitude limit of r'=24.5. I am mainly working on follow-up observation of the objects detected by OSSOS, primarily using the Subaru and Gemini North telescopes. The goal of these follow-up observations is to measure light curves and colors of the OSSOS KBOs in order to correlate surface, shape, and rotational properties with dynamical classification.

Finally, I am a member of the Hyper Suprime-Cam Subaru Strategic Program (HSC SSP). This survey comprises three components with different combinations of sky coverage and limiting magni- tude. The wide survey will cover 1400 sq. deg. down to magnitude r'=26, the deep survey will cover 27 sq. deg. down to r'=27, and the ultradeep survey will cover 3.5 sq. deg. down to r'=28. This program is not optimized for detection of KBOs, but a preliminary analysis of 221 sq. deg. of data from the wide survey has succeeded in discovering 231 previously unknown objects, with magnitudes as faint as r' = 25.3. Both the survey and analysis are ongoing, and this work will eventually result in a very accurate measurement of the KBO size distribution for objects with magnitudes 27>r'>25.

Journal Papers affiliated with ASIAA

  1. Chang C-K; Chen Y-T; Fraser WC; Yoshida F; Lehner MJ; Wang S-Y; Kavelaars J; Pike RE; Alexandersen M; Ito T; Choi Y-J; Granados Contreras AP; Jeongahn Y; Ji J; Kim M-J; Lawler SM; Li J; Lin Z-Y; Lykawka PS; Moon H-K; More S; Munoz-Gutierrez M; Ohtsuki K; Terai T; Urakawa S; Zhang H; Zhao H-B; The FOSSIL Collaboration, "FOSSIL. I. The Spin Rate Limit of Jupiter Trojans" , The Planetary Science Journal: 2(5), id.191 (11pp), Oct, 2021 [SCI] ( ADS | Fulltext )
  2. Fraser WC; Benecchi SD; Kavelaars JJ; Marsset M; Pike RE; Bannister MT; Schwamb ME; Volk K; Nesvorny D; Alexandersen M; Chen Y-T; Gwyn S; Lehner MJ; Wang S-Y, "Col-OSSOS: The Distinct Color Distribution of Single and Binary Cold Classical KBOs" , The Planetary Science Journal: 2(3), id.90 (6pp), Jun, 2021 ( ADS | Fulltext )
  3. Huang C-K; Lehner MJ; Granados Contreras AP; Castro-Chacón JH; Chen W-P; Alcock C; Alvarez-Santana FI; Cook KH; Geary JC; Guerrero Peña CA; Hernández-Ñguila JB; Hernández-Valencia B; Karr J; Kavelaars JJ; Norton T; Nuñez JM; Ochoa D; Reyes-Ruiz M; Sánchez E; Silva JS; Szentgyorgyi A; Wang S-Y; Yen W-L; Zhang Z-W, "The TAOS II Survey: Real-time Detection and Characterization of Occultation Events" , PASP: 133(1021), id.34503 (17pp), Mar, 2021 [SCI] ( ADS | Fulltext )
  4. Muñoz-Gutiérrez MA; Peimbert A; Lehner MJ; Wang S-Y, "Long-term Dynamical Stability in the Outer Solar System I: The Regular and Chaotic Evolution of the 34 Largest Trans-Neptunian Objects" , AJ: 162(4), id.164 (13pp), Oct, 2021 [SCI] ( ADS | Fulltext )
  5. Alexandersen M; Benecchi Sd; Chen Y-T; Eduardo MR; ...; Schwamb ME; Lehner MJ; Wang S-Y; et al., "OSSOS. XII. Variability Studies of 65 Trans-Neptunian Objects Using the Hyper Suprime-Cam" , ApJS: 244(1), id. 19 (49 pp.), Sep, 2019 [SCI] ( ADS | Fulltext )
  6. Castro-Chacon JH; Reyes-Ruiz M; Lehner MJ; Zhang ZW; ...; Alexandersen M; ...; Chu YH; ...; Huang CK; ...; Yen WL, "Occultations by Small Non-spherical Trans-Neptunian Objects. I. A New Event Simulator for TAOS II" , PASP: 131(1000), id. 064401 (10 pp.), Jun, 2019 [SCI] ( ADS | Fulltext )
  7. Chen Y-T; Gladman B; Volk K; ...; Lehner MJ; ...; Wang S-Y; ...; Alexandersen M; et al., "OSSOS. XVIII. Constraining Migration Models with the 2:1 Resonance Using the Outer Solar System Origins Survey" , ApJ: 158(5), id. 214 (17 pp.), Nov, 2019 [SCI] ( ADS | Fulltext )
  8. Marsset M; Fraser WeC; Pike RE; …; Alexandersen M; Chen Y-T; ...; Lehner MJ; …; Wang S-Y; et al., "Col-OSSOS: Color and Inclination Are Correlated throughout the Kuiper Belt" , AJ: 157(3), id. 94 (17 pp.), Mar, 2019 [SCI] ( ADS | Fulltext )
  9. Muñoz-Gutiérrez MA; Peimbert A; Pichardo B; Lehner MJ;Wang S-Y, "The Contribution of Dwarf Planets to the Origin of Jupiter Family Comets" , AJ: 158(5), id. 184 (14 pp.), Nov, 2019 [SCI] ( ADS | Fulltext )
  10. Schwamb ME; Fraser WC; Bannister MT; ...; Pike RE; ...; Lehner MJ; Wang S-Y; ...; Alexandersen M; Chen Y-T ;et al., "Col-OSSOS: The Colors of the Outer Solar System Origins Survey" , ApJS: 43(1), id. 12 (24 pp.), Jul, 2019 [SCI] ( ADS | Fulltext )
  11. Bannister MT; Gladman BJ; Kavelaars JJ; ...; Chen Y-T; Alexandersen M; ...; Schwamb ME; ...; Lehner M; ...; Pike RE; ...; Wang SY, "OSSOS. VII. 800+ Trans-Neptunian Objects—The Complete Data Release" , ApJS: 236(1), 18, May, 2018 [SCI] ( ADS | Fulltext )
  12. Chen Y-T; Lin H-W; Alexandersen M; Lehner MJ; Wang S-Y; Wang J-H; et al., "Searching for moving objects in HSC-SSP: Pipeline and preliminary results" , PASJ: 70(SP1), S38 (17 pp.), Jan, 2018 [SCI] ( ADS | Fulltext )
  13. Bannister MT; Schwamb ME; Fraser WC; …; Pike RE; …; Wang S-Y; Lehner M, "Col-OSSOS: Colors of the Interstellar Planetesimal 1I/`Oumuamua" , ApJL: 851(2), L38, Dec 20, 2017 [SCI] ( ADS | Fulltext )
  14. Fraser WC; Bannister MT; Pike RE;…; Schwamb ME; …; Lehner MJ; …; Chen Y-T; Wang S-Y; Alexandersen M; et al., "All planetesimals born near the Kuiper belt formed as binaries" , Nature Astronomy: 1, 0088, April, 2017 [SCI] ( ADS | Fulltext )
  15. Pike RE; Fraser WC; Schwamb ME;...; Lehner MJ; Wang S-Y; Alexandersen M; Chen Y-T; et al., "Col-OSSOS: z-Band Photometry Reveals Three Distinct TNO Surface Types" , AJ: 154(3), 101, Sept, 2017 [SCI] ( ADS | Fulltext )
  16. Bannister MT; Alexandersen M; Benecchi SD; Chen Y-T; ...; Lehner MJ; ...; Schwamb ME; ...; Wang S-Y; et al., "OSSOS: IV. Discovery of a dwarf planet candidate in the 9:2 resonance with Neptune" , AJ: 152(6), 212, Dec, 2016 [SCI] ( ADS | Fulltext )
  17. Bannister MT; Kavelaars JJ; Petit J-M; ...; Chen Y-T; ...; Alexandersen M; ...; ...; Lehner MJ; ...; Schwamb ME; ...; Wang S-Y, "The Outer Solar System Origins Survey. I. Design and First-quarter Discoveries" , AJ: 152(3), 70, Sept, 2016 [SCI] ( ADS | Fulltext )
  18. Chen Y-T; Lin HW; Holman MJ; ...; Wang SY; Lehner MJ, "Discovery of a New Retrograde Trans-Neptunian Object: Hint of a Common Orbital Plane for Low Semimajor Axis, High-inclination TNOs and Centaurs" , ApJL: 827(2), 24, Aug 20, 2016 [SCI] ( ADS | Fulltext )
  19. Kimura M; Isogai K; Kato T; ...; Chen Y-T; King S-K; Wen C-Y; Wang SY; Lehner MJ; Schwamb ME; Wang J-H; Zhang Z-W; ...;Cook KH; Kim D-W; Lee T;et al. (the TAOS collaboration), "Repetitive Patterns in Rapid Optical Variations in the Nearby Black-hole Binary V404 Cygni" , Nature: 529(7584), 54-58, Jan, 2016 [SCI] ( ADS | Fulltext )
  20. Griest K; Cieplak AM; Lehner MJ, "Experimental Limits on Primordial Black Hole Dark Matter from the First 2 yr of Kepler Data" , ApJ: 786(2), 158, May, 2014 [SCI] ( ADS | Fulltext )
  21. Ishioka R; Wang S-Y; Zhang Z-W; Lehner MJ; Alcock C; Axelrod T; Bianco FB; Byun Y-I; Chen WP; Cook KH; Kim D-W; King S-K; Lee T; Marshall SL; Protopapas P; Rice JA; Schwamb ME; Wang J-H; Wen C-Y; Ngeow C-C, "The Taiwanese-American Occultation Survey Project Stellar Variability. III. Detection of 58 New Variable Stars" , AJ: 147(4), 70, April, 2014 [SCI] ( ADS | Fulltext )
  22. Griest K; Cieplak AM; Lehner MJ, "New Limits on Primordial Black Hole Dark Matter from an Analysis of Kepler Source Microlensing Data" , Phys Rev Lett: 111(18), 181302, Nov, 2013 [SCI] ( ADS | Fulltext )
  23. Zhang Z-W; Lehner MJ; Wang J-H; Wen C-Y; Wang S-Y; King S-K; ...; Cook KH; ...; Lee T; ...; Schwamb ME, "The TAOS Project: Results from Seven Years of Survey Data" , AJ: 146(1), 14, July, 2013 [SCI] ( ADS | Fulltext )
  24. Huang KY; Urata Y; Tung YH; Lin HM; ...; Wang SY; ...; Lehner MJ; ...; Wang J-H; Wen CY; ...; Zhang ZW; et al., "The GRB 071112C: A Case Study of Different Mechanisms in X-ray and Optical Temporal Evolution" , ApJ: 748(1), 44-50, Mar, 2012 [SCI] ( ADS | Fulltext )
  25. Griest K; Lehner MJ; Cieplak AM; Jain B, "Microlensing of Kepler Stars as a Method of Detecting Primordial Black Hole Dark Matter" , Phys Rev Lett: 107(23), 231101, Dec 1, 2011 [SCI] ( ADS | Fulltext )
  26. Bianco FB; Zhang ZW; Lehner MJ; ...; Wang J-H; ...; King SK; ...; Lee T; ...; Wang SY; Wen CY, "The TAOS Project: Upper Bounds on the Population of Small KBOs and Tests of Models of Formation and Evolution of the Outer Solar System" , AJ: 139(4), 1499-1514, April, 2010 [SCI] ( ADS | Fulltext )
  27. Kim D-W; ...; King S-K; Lee T; Lehner MJ; ...; Wang J-H; Wang SY; Wen C-Y; Zhang Z-W, "The Taiwan-American Occultation Survey Project Stellar Variability. I. Detection of Low-Amplitude δ Scuti Stars" , AJ: 139(2), 757-764, Feb, 2010 [SCI] ( ADS | Fulltext )
  28. Lehner MJ; Coehlo NK; Zhang Z-W;...; Wang J-H; ...; King SK; Lee T; ...; Wang SY; Wen CY, "The TAOS Project: Statistical Analysis of Multi-Telescope Time Series Data" , PASP: 122(894), 959-975, Aug, 2010 [SCI] ( ADS | Fulltext )
  29. Mondal S; ...; Zhang ZW;...; King S-K; Lee T; Lehner MJ; ...; Wang J-H; Wang SY; Wen C-Y, "The Taiwanese-American Occultation Survey Project Stellar Variability. II. Detection of 15 Variable Stars" , AJ: 139(5), 2026-2033, May, 2010 [SCI] ( ADS | Fulltext )
  30. Bianco FB; ...; Lehner MJ, "A Search for Occultations of Bright Stars by Small Kuiper Belt Objects Using Megacam on the MMT" , AJ: 138(2), 568-578, Aug, 2009 [SCI] ( ADS | Fulltext )
  31. Lehner MJ; Wen C-Y; Wang J-H; ...; King S-K; et al., "The Taiwanese-American Occultation Survey: The Multi-Telescope Robotic Observatory" , PASP: 121(876), 138-152, Feb 2009, 2009 [SCI] ( ADS | Fulltext )
  32. Lin CL; ...; King SK; ...; Wang J-H;...; Lehner MJ; ...; Lee T; ...; Wang SY; Wen CY; et al., "A Close Binary Star Resolved from Occultation by 87 Sylvia" , PASP: 121(878), 359-364, April 2009, 2009 [SCI] ( ADS | Fulltext )
  33. Wang J-H; Lehner MJ; Zhang Z-W; ...; King S-K; Lee T; ...; Wang SY; Wen C-Y; et al., "Upper Limits on the Number of Small Bodies in Sedna-Like Orbits by the TAOS Project" , AJ: 138(6), 1893-1901, Dec, 2009 [SCI] ( ADS | Fulltext )
  34. Zhang ZW; Kim DW; Wang J-H; Lehner MJ; Chen WP; Byun YI; Alcock C; Axelrod T; Bianco FB; Coehlo NK; Cook KH; Dave R; de Pater I; Giammarco J; King SK; Lee T; Lin HC; Marshall SL; Porrata R; Protopapas P; Rice JA; Schwamb ME; Wang SY; Wen CY, "The TAOS Project: High-Speed Crowded Field Aperture Photometry" , PASP: 121(886), 1429-1439, Dec, 2009 [SCI] ( ADS | Fulltext )
  35. Wang J-H; Schwamb ME; Huang KY; Wen CY; ...; Wang SY; ...; Lehner MJ; ...; King SK; Lee T; Urata Y, "The Early Optical Brightening in the GRB071010B" , ApJ: 679(1), L5-L8, May 20, 2008 [SCI] ( ADS | Fulltext )
  36. Zhang ZW; ...; Lehner MJ; ...; Wang J-H; ...; King SK; Lee T; ...; Wang SY; Wen CY, "First Results from the Taiwanese-American Occultation Survey (TAOS)" , ApJ: 685(1), L157-L160, Oct 1, 2008 [SCI] ( ADS | Fulltext )
  37. King S-K; Alcock C; Axelrod T; Bianco FB; Byun Y-I; Chen W-P; Cook KH; Chang Y-H; Dave R; Giammarco J; Lee T; Lehner M; Lissauer J; Marshall S; Mondal S; De Pater I; Porrata R; Rice J; Schwamb ME; Wang A; Wang S-Y; Wen C-Y; Zhang Z-W, "Status of the TAOS Project and a Simulator for TNO Occultation" , Advances in Geosciences: 3, 345-358, May, 2006 ( ADS | Fulltext )
TEL: 886-2-3365-2200 FAX: 886-2-2367-7849
General: asiaa_replace2@_asiaa.sinica.edu.tw Media Request: epo_replace2@_asiaa.sinica.edu.tw
11F of AS/NTU Astronomy-Mathematics Building, No.1, Sec. 4, Roosevelt Rd, Taipei 10617, Taiwan, R.O.C.