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The Pan-STARRS search for Near - Present Status and Future Plans

Richard Wainscoat Peter Vereš, Bryce Bolin, , Larry Denneau, Robert Jedicke, Serge Chastel University of , Institute for The Pan-STARRS

Pan-STARRS1 is a 1.8-meter diameter at Haleakala observatory in (PS1) A second telescope (PS2) is being built adjacent to PS1 PS1 has the largest digital camera in the world 60 CCDs, each with 4800x4800 pixels, arranged in an 8x8 grid of 600x600 pixels Gigapixel camera

1,382,400,000 pixels 7 square degree field-of-view Read time 12 sec Some CCDs are cosmetically poor 70% fill factor Pan-STARRS1 mission The observations that Pan-STARRS1 is obtaining are designed for many different scientific goals, including the , brown dwarfs, Galactic structure, supernovae and other transients, and cosmology Nearly all observations that Pan-STARRS 1 obtains are executed in a manner that allows them to be searched for Near Earth Objects NASA is funding the NEO search with PS1 Astrometry from PS1 is excellent, and in most cases is better than 0.15 arcsec 3pi survey

Entire sky north of –30 surveyed every year 2,500 square degrees observed every month using 56% of the observing time Two pairs in each of g, r, and i (12 observations total) Each pair separated by approximately 20 minutes The entire area is observed at least once as a quad (four observations each spaced 20 minutes apart) 239 NEOs discovered to date including 24 PHAs webviz 10/16/12 11:01 AM

MDRM Viewer

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October 3pi fields Show: (Examples: "3pi", "3pi r 1")

Previous night

Chunk Name 157.3PI.00.BNE1.J.g 157.3PI.00.BNE1.J.i 157.3PI.00.BNE1.J.r 157.3PI.00.BNE1.K.g 157.3PI.00.BNE1.K.i 157.3PI.00.BNE1.K.r 157.3PI.00.BNE2.J.g 157.3PI.00.BNE2.J.i 157.3PI.00.BNE2.J.r 157.3PI.00.BNE2.K.g 157.3PI.00.BNE2.K.i 157.3PI.00.BNE2.K.r 157.3PI.00.BNE3.J.g 157.3PI.00.BNE3.J.i 157.3PI.00.BNE3.J.r 157.3PI.00.BNE3.K.g 157.3PI.00.BNE3.K.i 157.3PI.00.BNE3.K.r 157.3PI.00.BNO1.J.g 157.3PI.00.BNO1.J.i 157.3PI.00.BNO1.J.r 157.3PI.00.BNO1.K.g 157.3PI.00.BNO1.K.i 157.3PI.00.BNO1.K.r 157.3PI.00.BNO2.J.g 157.3PI.00.BNO2.J.i 157.3PI.00.BNO2.J.r 157.3PI.00.BNO2.K.g 157.3PI.00.BNO2.K.i 157.3PI.00.BNO2.K.r 157.3PI.00.BNO3.J.g 157.3PI.00.BNO3.J.i 157.3PI.00.BNO3.J.r 157.3PI.00.BNO3.K.g Hammer-Aitoff | Spherical 157.3PI.00.BNO3.K.i 157.3PI.00.BNO3.K.r 157.3PI.00.BNW1.J.g 157.3PI.00.BNW1.J.i 157.3PI.00.BNW1.J.r 157.3PI.00.BNW1.K.g 157.3PI.00.BNW1.K.i 157.3PI.00.BNW1.K.r 157.3PI.00.BNW2.J.g 157.3PI.00.BNW2.J.i 157.3PI.00.BNW2.J.r 157.3PI.00.BNW2.K.g 157.3PI.00.BNW2.K.i 157.3PI.00.BNW2.K.r 157.3PI.00.BNW3.J.g 157.3PI.00.BNW3.J.i 157.3PI.00.BNW3.J.r 157.3PI.00.BNW3.K.g 157.3PI.00.BNW3.K.i 157.3PI.00.BNW3.K.r 157.3PI.00.BSE1.J.g 157.3PI.00.BSE1.J.i 157.3PI.00.BSE1.J.r 157.3PI.00.BSE1.K.g 157.3PI.00.BSE1.K.i 157.3PI.00.BSE1.K.r 157.3PI.00.BSE2.J.g 157.3PI.00.BSE2.J.i 157.3PI.00.BSE2.J.r 157.3PI.00.BSE2.K.g 157.3PI.00.BSE2.K.i 157.3PI.00.BSE2.K.r 157.3PI.00.BSE3.J.g 157.3PI.00.BSE3.J.i 157.3PI.00.BSE3.J.r 157.3PI.00.BSE3.K.g 157.3PI.00.BSE3.K.i 157.3PI.00.BSE3.K.r 157.3PI.00.BSO1.J.g 157.3PI.00.BSO1.J.i 157.3PI.00.BSO1.J.r 157.3PI.00.BSO1.K.g 157.3PI.00.BSO1.K.i 157.3PI.00.BSO1.K.r http://ipp0022.ifa.hawaii.edu/ps1sc/denneau/157/hammer.html Page 1 of 3 webviz 10/16/12 11:00 AM

MDRM Viewer

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November 3pi fields Show: (Examples: "3pi", "3pi r 1")

Previous night

Chunk Name 158.3PI.00.ANE1.J.g 158.3PI.00.ANE1.J.i 158.3PI.00.ANE1.J.r 158.3PI.00.ANE1.K.g 158.3PI.00.ANE1.K.i 158.3PI.00.ANE1.K.r 158.3PI.00.ANE2.J.g 158.3PI.00.ANE2.J.i 158.3PI.00.ANE2.J.r 158.3PI.00.ANE2.K.g 158.3PI.00.ANE2.K.i 158.3PI.00.ANE2.K.r 158.3PI.00.ANE3.J.g 158.3PI.00.ANE3.J.i 158.3PI.00.ANE3.J.r 158.3PI.00.ANE3.K.g 158.3PI.00.ANE3.K.i 158.3PI.00.ANE3.K.r 158.3PI.00.ANO1.J.g 158.3PI.00.ANO1.J.i 158.3PI.00.ANO1.J.r 158.3PI.00.ANO1.K.g 158.3PI.00.ANO1.K.i 158.3PI.00.ANO1.K.r 158.3PI.00.ANO2.J.g 158.3PI.00.ANO2.J.i 158.3PI.00.ANO2.J.r 158.3PI.00.ANO2.K.g 158.3PI.00.ANO2.K.i 158.3PI.00.ANO2.K.r 158.3PI.00.ANO3.J.g 158.3PI.00.ANO3.J.i 158.3PI.00.ANO3.J.r 158.3PI.00.ANO3.K.g Hammer-Aitoff | Spherical 158.3PI.00.ANO3.K.i 158.3PI.00.ANO3.K.r 158.3PI.00.ANO4.K.g 158.3PI.00.ANO4.K.i 158.3PI.00.ANO4.K.r 158.3PI.00.ANW1.J.g 158.3PI.00.ANW1.J.i 158.3PI.00.ANW1.J.r 158.3PI.00.ANW1.K.g 158.3PI.00.ANW1.K.i 158.3PI.00.ANW1.K.r 158.3PI.00.ANW2.J.g 158.3PI.00.ANW2.J.i 158.3PI.00.ANW2.J.r 158.3PI.00.ANW2.K.g 158.3PI.00.ANW2.K.i 158.3PI.00.ANW2.K.r 158.3PI.00.ANW3.J.g 158.3PI.00.ANW3.J.i 158.3PI.00.ANW3.J.r 158.3PI.00.ANW3.K.g 158.3PI.00.ANW3.K.i 158.3PI.00.ANW3.K.r 158.3PI.00.ASE1.J.g 158.3PI.00.ASE1.J.i 158.3PI.00.ASE1.J.r 158.3PI.00.ASE1.K.g 158.3PI.00.ASE1.K.i 158.3PI.00.ASE1.K.r 158.3PI.00.ASE2.J.g 158.3PI.00.ASE2.J.i 158.3PI.00.ASE2.J.r 158.3PI.00.ASE2.K.g 158.3PI.00.ASE2.K.i 158.3PI.00.ASE2.K.r 158.3PI.00.ASE3.J.g 158.3PI.00.ASE3.J.i 158.3PI.00.ASE3.J.r 158.3PI.00.ASE3.K.g 158.3PI.00.ASE3.K.i 158.3PI.00.ASE3.K.r 158.3PI.00.ASO1.J.g 158.3PI.00.ASO1.J.i 158.3PI.00.ASO1.J.r http://ipp0022.ifa.hawaii.edu/ps1sc/denneau/158/hammer.html Page 1 of 3 NEO Optimized survey

We use a broad w-band filter (g+r+i) to increase sensitivity and have 11% of the observing time Four 45 second exposures separated by 20 minutes in the direction or 7 minutes in the low solar sweet spot directions, using wide filter Opposition search has yielded 536 NEO discoveries, including 41 PHAs Sweet spot search has yielded 28 NEO discoveries, including 11 PHAs September 2013 solar system fields The need for followup observations

Pan-STARRS NEO candidates are submitted to the Minor Center Pan-STARRS does not followup its own NEO candidates We follow up some NEO candidates with CFHT PS1 is extremely dependent on other people to followup candidates to produce discoveries Submissions to MPC

2,279,348 tracklets reported to date 7,223,594 detections 563,836 distinct asteroids 40,357 asteroid discoveries 3,000–6,000 asteroids submitted per night Discovery rate

PS1 discovers over 50 NEOs per month when the weather is good The median H for PS1 NEO discoveries for 2012 and 2013 is 22.4 Other NEO discoveries (mostly from the ) have median H=23.4 Pan-STARRS is good at finding larger undiscovered NEOs that are distant and faint, but less efficient at finding smaller fast-moving nearby NEOs 2012 and 2013 NEO discoveries

200

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0

20 25 30 H magnitude 2012 and 2013 NEO discoveries

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F51 80

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40 703

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20 25 30 H magnitude 2012 and 2013 NEO discoveries

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Other 60

40 F51

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1234 Semi-major axis

Pan-STARRS has discovered many comets and is efficient at discovering low levels of activity Five Main Belt Comets have been discovered to date P2013/R3

September

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! October Future plans

The Pan-STARRS1 Science Consortium survey will finish at the end of February 2014 We are planning to conduct an NEO optimized survey using 100% of the observing time beginning in 2014 This will enable a much larger area of the sky to be surveyed multiple times per month We can survey further south, reaching to -40˚ Digest scores of NEOs observed by PS1

PS1 NEO 1.0 a 0.9

0.8

0.7 0.6 0.5

0.4 Normalised count 0.3

0.2 0.1 0.0 0 10 20 30 40 50 60 70 80 90 100 NEO digest score Sky coverage with 100% of Pan-STARRS1 Pan-STARRS2

Pan-STARRS2 is nearing completion adjacent to PS1 Adding a second telescope will enable us to survey a large fraction of the sky multiple times each lunation PS2 image of the Crab Nebula Sky coverage with 100% of Pan-STARRS1&2 Camera retrofit

The CCDs in the Pan- STARRS telescopes are not ideal Cosmetic quality of some devices is poor Cell structure in CCDs hinders discovery of faster moving NEOs Example of fast moving asteroid detection compromised by cell gaps Camera retrofit

Better CCDs would increase our discovery rate by a factor of almost 2