J/AJ/133/1247 Solar system survey with Spacewatch (Larsen+, 2007)
The search for distant objects in the solar system using Spacewatch.
Larsen J.A., Roe E.S., Albert C.E., Descour A.S., McMillan R.S.,
Gleason A.E., Jedicke R., Block M., Bressi T.H., Cochran K.C., Gehrels T.,
Montani J.L., Perry M.L., Read M.T., Scotti J.V., Tubbiolo A.F.
<Astron. J., 133, 1247-1270 (2007)>
=2007AJ....133.1247L 2007AJ....133.1247L
ADC_Keywords: Surveys ; Minor planets ; Solar system
Keywords: Kuiper Belt - minor planets, asteroids - solar system: formation -
surveys
Abstract:
We have completed a low-inclination ecliptic survey for distant and
slow-moving bright objects in the outer solar system. This survey used
data taken over 34 months by the University of Arizona's Spacewatch
Project based at Steward Observatory, Kitt Peak. Spacewatch revisits
the same sky area every three to seven nights in order to track
cohorts of main-belt asteroids. This survey used a multiple-night
detection scheme to extend our rate sensitivity to as low as
0.012"/hr. When combined with our plate scale and flux sensitivity
(V∼21), this survey was sensitive to Mars-sized objects out to 300AU
and Jupiter-sized planets out to 1200AU. The survey covered
approximately 8000deg2 of raw sky, mostly within 10° of the
ecliptic but away from the Galactic center. An automated motion
detection program was modified for this multinight search and
processed approximately 2 terabytes of imagery into motion candidates.
This survey discovered 2003 MW12, currently the tenth largest
classical Kuiper Belt object. In addition, several known large Kuiper
Belt objects and Centaurs were detected, and the detections were used
with a model of our observational biases to make population estimates
as a check on our survey efficiency. We found no large objects at low
inclinations despite having sufficient sensitivity in both flux and
rate to see them out as far as 1200AU. For low inclinations, we can
rule out more than one to two Pluto-sized objects out to 100AU and one
to two Mars-sized objects to 200AU.
Description:
Our data were collected at the 0.9 meter Spacewatch telescope (IAU
observatory code 691) at the Steward Observatory on Kitt Peak in
Arizona as part of its normal near-Earth asteroid search.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 215 3930 Entries for the pointing history of the survey
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Name Processing name of region
26- 29 I4 --- Num Number of generated candidate motions
at S/N=3
31- 36 F6.4 deg2 Cover Overlapped sky coverage between nights
38- 39 I2 h RAh ? Earlier night Right Ascension (J2000)
41- 42 I2 min RAm ? Earlier night Right Ascension (J2000)
44- 49 F6.3 s RAs ? Earlier night Right Ascension (J2000)
51 A1 --- DE- Earlier night Declination Sign (J2000)
52- 53 I2 deg DEd ? Earlier night Declination (J2000)
55- 56 I2 arcmin DEm ? Earlier night Declination (J2000)
58- 62 F5.2 arcsec DEs ? Earlier night Declination (J2000)
64- 73 A10 "YYYY/MM/DD" Obs.date ? UT Date of earlier night
75- 84 A10 "h:m:s" Obs.time ? Earlier UT Hour of shutter open (1)
86- 91 I6 --- Obj ?=0 Earlier night number of detected
matched objects
93- 96 F4.1 arcsec FWHM Earlier night average FWHM of the stellar
profile between the images
98-128 A31 --- Obser Earlier night observer identities
130-131 I2 h RA2h ? Later night Right Ascension (J2000)
133-134 I2 min RA2m ? Later night Right Ascension (J2000)
136-141 F6.3 s RA2s ? Later night Right Ascension (J2000)
143 A1 --- DE2- Later night Declination sign (J2000)
144-145 I2 deg DE2d ? Later night Declination (J2000)
147-148 I2 arcmin DE2m ? Later night Declination (J2000)
150-154 F5.2 arcsec DE2s ? Later night Declination (J2000)
156-165 A10 "YYYY/MM/DD" Obs2.date ? UT Date of later night
167-177 A11 "h:m:s" Obs2.time ? Later UT Hour of shutter open (1)
179-184 I6 --- Obj2 ?=0 Later night number of detected matched
objects
186-189 F4.1 arcsec FWHM2 Later night average FWHM of the stellar
profile between the images
191-215 A25 --- Obser2 Later night observer identities
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Note (1): Midexposure time 60 seconds later.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 04-Feb-2009