8. White Dwarf WD 1145+017 Photometric Monitoring Observations by Amateur Observer Bruce Gary
B. L. Gary, this is the 8th of 8 web pages devoted to my observations of WD1145. Last updated 2021.09.15

1 of 9 - 2015.11.01 to 2016.01.21:  LC Observations  - 1st  set of LCs, for 2015/16 observing season   
2 of 9 - 2016.01.17 to 2016.07.13:  LC Observations  - 2nd set of LCs, for 2015/16 observing season    
3 of 9 - 2015.11.01 to 2016.07.13:  LC Observations  - 3rd set of LCs, for 2015/16 observing season  (N = 158) + Overview, Results & Model Speculations 
4 of 9 - 2016.10.25 to 2017.06.18:  LC Observations  - 4th set of LCs, for 2016/17 observing season 
5 of 9 - 2017.10.23 to 2018.06.19:  LC Observations  - 5th set of LCs, for 2017/18 observing season 
6 of 9 - 2018.11.06 to 2018.07.09   LC Observations  - 6th set of LCs, for 2018/19 observing season 
7 of 9 - 2019.12.02 to 2020.07.09   LC Observations  - 7th set of LCs, for 2019/20 observing season
 
          All previous observing seasons summary of results:    Observational findings that need to be explained by models
 
8 of 9 - 2020.11.19 to 2021.06.07   LC Observations  - 8th set of LCs, for 2020/21 observing season   (YOU ARE HERE)
 9 of 9 - 2020.12.12 to present 

Links on this web page:

  Status & Summary of Results for recent observations  
  Observing session LCs 
  Finder image & basic info  
  Data exchange files (for all years: 2015/16, 2016/17, etc)
  My collaboration policy 
  References & related external links 
  Summary of  3.7 years of ground-based LC measurements 
  Collisions (tutorial: Collisions for Dummies, other web site)   
  Cloud crossing event (on another web page)

Status & Summary of Results for this Observing Season: 















The following sequence of phase-folded light curves can be used to study the recent evolution of dip activity.













The next two graphs show dust production "dip activity" level vs. date.






List of observing sessions   

2021.06.07  
2021.05.31  
2021.05.30  
2021.05.29  
2021.05.28  
2021.05.19  
2021.05.14  
2021.05.08  
2021.05.07  
2021.05.01  
2021.04.09  
2021.03.31  
2021.03.23  
2021.03.21  
2021.03.20  
2021.03.19  
2021.03.19  
2021.03.18  
2021.03.17  
2021.03.15  
2021.03.14  
2021.03.11  
2021.03.07  
2021.03.06  
2021.03.03  
2021.03.02  
2021.02.24  
2021.02.23  
2021.02.22  
2021.02.20  
2021.02.19  
2021.02.15  
2021.01.17  
2021.01.10  
2020.12.20
2020.11.20  
2020.11.19  

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2021.06.07  


Windy; not worth processing further.

2021.05.31  





2021.05.30  









2021.05.29  


No brightening feature like yesterday, so I'll attribute yesterday's feature to something mysterious such as an asteroid passing by. Also, this night's RMS noise levels are better than last night, so yesterday's two possible dips that are not present in this LC are suspicious. .

2021.05.28  


I've never seen such a thing as this rise in brightness lasting ~ 1/2 hour. I doubt that it's real. It could be an asteroid drifting past WD1148. Let's see if it is present tomorrow.

2021.05.19  





2021.05.14  


This is close to an all-time low level of activity during the 6 years of ground-based foloow-up to Kepler data. Only one "lonely" dip!



2021.05.08  





2021.05.07  



2021.05.01  







2021.04.09  







2021.03.31  









2021.03.23  







2021.03.21  








Lots of clouds!

2021.03.20  











2021.03.19  









2021.03.18  







2021.03.17  





2021.03.15  










2021.03.14  









2021.03.11  





2021.03.07  









2021.03.06  





2021.03.03  







2021.03.02  









2021.02.24  







2021.02.23  







2021.02.22  





2021.02.20  





2021.02.19  





2021.02.15  





2021.01.17  







2021.01.10







2020.12.20 

The shift rightward of this dip compared to the previous observing session (30 days ago) implies that the dip has P = 1.4955 hrs (slightly larger orbit than most dip sources).







2020.11.20  







2020.11.19  








Finder Image  


Finder image. FOV = 15.6 x 10.5 'arc. North up, east left. (Image taken with 16" AstroTech .)

RA/DE = 11:48:33.6 +01:28:29, B-V = +0.26, r'-mag = 17.2, Teff = 15,020 K (young cooling age ~ 224 My), Spectral Type DBZA, He atmosphere, photospheric absorption lines for 11 "metals," star mass = 0.63 M_sun, R = 1.29 R_earth, distance = 142 parsec.

Data Exchange Files   

    2015.11.21 to 2016.07.15  
    2016.10.25 to 2017.06.18  
    2017.11.10 to 2018.06.18 
    2018.11.09 to 2019.06.09 
    2019.12.02 to 2020.07.09  
    2020.12.xx to 2021.03.22  (more to come)

Data exchange files are available in two formats: light curve details (one line per image) and dip fits (asymmetric hypersecant (AHS) model fits for each dip). The first of these is available for download using the above links (though I recommend that anyone using these data check with me for updates since I sometimes find errors and post the corrected files here). Data exchange files of the second format (AHS dip fits) may be requested from B.Gary. These may also be available here in due time.

My Collaboration Policy

Please don't ask me to co-author a paper! At my age of 81 I'm entitled to have fun and avoid work. Observing and figuring things out is fun; writing papers is work.

My observations are now "in the public domain" for this observing season (2020/21). If my data is essential to any publication just mention this in the Acknowledgement section.

 

References


    Farihi, J., J. J. Hermes, T. R. Marsh & 11 others, 2021, "Relentless and Complex Transits from a Planetesimal Debris Disk," submitted to MNRAS, arXiv 
    Guidry, Joseph A., Zachary P. Vanderbosch, J. J. Hermes & 13 others, 2020, "I Spy Transits and Pulsations: Empirical Variability in White Dwarfs Using Gaia and the Zwicky Transient Facility," ApJ, arXiv
    Duvvuri,Girish M., Seth Redfield and Dimitri Veras, 2021, "Necroplanetology: Simulating the Tidal Disruption of Differentiated Planetary Material Orbiting WD 1145+017," accepted by ApJ, arXiv 
    Steckloff, Jordan K., John Debes, Amy Steele, Brandon Johnson, Elizabeth R. Adams, Seth A. Jacobson, Alessondra Springman, "How Sublimation Delays the Obset of Dusty Debris Disk Formation Around White Dward Stars," 2021, arXiv
    Duvvuri, Girish M., Seth Redfield and Dimitri Veras, 2020, "Necroplanetology: Simulating the Tidal Disruption of Differentiated Planetary Material Orbiting WD 1145+017," submitted to ApJ, arXiv
    Fortin-Archambault, M., P. Dufour, S. Xu, 2019, "Modeling of the Variable Circumstellar Absorption Features of WD 1145+017," arXiv
    Xu, Siyi, Na'ama Hallokoun, Bruce Gary, Paul Dalba, John Debes and 14 others, 2019, "Shallow Ultraviolet Transits of WD 1145+017," arXiv 
    Gansicke, Boris T., Matthias R. Schreiber, Odette Toloza, Nicola P. Gentile Fusillo, Detlev Koester and Christopher L. Manser, 2019, "Accretion of a Giant Planet onto a White Dwarf," arXiv
    Gansicke, Boris + 26 others, 2019, "Evolved Planetary Systems around White Dwarfs," Astro 2020 Science White paper, arXiv
    Manser, Christopher + 31 others, 2019, "A Planetesimal Orbiting the Debris Disk around a White Dwarf Star," arXiv
    Veras, Dimitri + 8 others, 2019, "Orbital Relaxation and Excitation of Planets Tdally Interacting with White Dwarfs," arXiv  
    Vanderburg, Andrew and Saul A. Rappaport, 2018, "Transiting Disintegrating Debris around WD 1145+017," arXiv 
    Rappaport, S. B. L. Gary, A. Vanderburg, S. Xu, D. Pooley & K. Mukai, "WD 1145+017: Optical Activity During 2016-2017 and Limits on the X-Ray Flux," MNRAS, arXiv 
    Xu, S., S. Rappaport, R. van Lieshout & 35 others, "A dearth of small particles in the transiting material around the white dwarf WD 1145+017," MNRAS link, preprint arXiv: 1711.06960 
    Vanderburg et al, 2015, "A Disintegrating Minor Planet Transiting a White Dwarf," Nature, 2015 Oct 22, arXiv:1510.063387
    Croll et al, 2105, "Multiwavelength Transit Observations of the Candidate Disintegrating Planetesimal Orbiting WD 1145+017," ApJ, arXiv:1510.06434 
    Gaensicke et al, 2015, "High-Speed Photometry of the Disintegrating Planetesimal at WD 1145+017: Evidence for Rapid Dynamical Evolution," arXiv :1512.09150
    Redfield, Seth, Jay Farihi, P. Wilson Cauley, Steven G. Parsons, Boris T. Gansicke and Girish Duvvuri, 2016, "Spectroscopic Evolution of Disintegrating Planetesimals: Minutes to Months Variability in the Circumstellar Gas Associated with WD 1145+017,"  ApJ, 839, 42, arXiv 
    Rappaport, S., B. L. Gary, T. Kaye, A. Vanderburg, B. Croll, P. Benni & J. Foote, 2016, "Drifting Asteroid Fragments Around WD 1145+017," MNRAS, arXiv:1602.00740
    Alonso, R., S. Rappaport, H. J. Deeg and E. Palle, 2016, "Gray Transits of WD 1145+017 Over the Visible Band," Astron. & Astrophys., arXiv:1603.08823
    Petit, J.-M and M. Henon, 1986, Icarus, 66, 536-555 (link)
    Veras, Dimitri, Philip J. Carter, Zoe M. Leinhardt and Boris T. Gansicke, 2016, arXiv 
    Gary, B. L., S. Rappaport, T. G. Kaye, R. Alonso and F.-J. Hamsch, "WD 1145+017 Photometric Observations During Eight Months of High Activity," 2017, MNRAS, 465, 3267-3280. PDF  or arXiv  
    Hallakoun, N., S. Xu, D. Maoz, T.R. Marsh, V. D. Ivanov, V. S. Dhillon, M. C. P. Bours, S. G. Parsons, P. Kerry, S. Sharma, K. Su, S. Rengaswamy, P. Pravec, P. Kusnirak, H. Kucakova, J. D. Armstrong, C. Arnold, N. Gerard, L. Vanzi, 2017, Earth and Planetary Astrophysics, arXiv 1702.05486
    Farihi, J., L. Fossati, P. J. Wheatley, B. D. Metzger, J. Mauerhan, S. Bachman, B. T. Gansicke, S. Redfield, P. W. Cauley, O. Kochukhov, N. Achilleos & N. Stone, "Magnetism, X-ras, and Accretion Rates in WD 1145+017 and other Polluted White Dwarf Systems, MNRAS, arXiv
    Tom Kaye presentation at 2016 Society for Astronomical Science meeting: link   

Related Links  
    Mukremin Kilic's pro/am search of dusty WDs for dips:  https://www.nhn.ou.edu/%7Ekilic/Docs/dusty.html
    Some observing "good practices" for amateurs (book): Exoplanet Observing for Amateurs
    Hereford Arizona Observatory (HAO):  http://www.brucegary.net/HAO/
    Tutorial for faint object observing techniques using amateur hardware: http://brucegary.net/asteroids/  
    Master list of my web pages & Resume

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WebMaster:   Nothing on this web page is copyrighted. This site opened:  2020 November 20