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"What has the sea level elevation of the Pacific Ocean been at varied periods in the last 4.5 billion years."
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The Size Distribution of Small KBOs
Project Investigators: David Jewitt, Jan Kleyna
Summary
We are stacking ultra-deep images obtained using the wide-field Suprime-Cam imager on the Subaru telescope to measure the size distribution of small (~10 km) Kuiper Belt objects. Previous measurements of the size distribution have been limited to brighter magnitudes, but this survey exploits the sensitivity and wide field coverage of Suprime-Cam to reach a limiting magnitude >25 over a square degree, allowing us to study the distribution of very small objects.
Astrobiology Roadmap Objectives:
Project Progress
We are using the stacking techniques that we developed in our recovery attempt of 85P/Boethin for the EPOXI mission to stack four fields of Subaru Suprime-Cam data, taken over two nights. By stacking on a fine grid of rates, we will be able to detect KBOs moving at a range of orbital speeds. Our noise-suppression techniques of static sky subtraction and star-masking developed for 85/P are being used to minimize false noise detections, and cross-matching of detections between the two nights further suppresses false positives.
We then compute the true (excess over noise) detection rate using the twin null-tests of considering retrograde motion, and of perturbing night 1 in relation to night 2 to break their correspondence and leave only random matches.
Simulation of KBOs recovery from images stacked at a grid of orbital speeds (corresponding to circular orbit distance) and inclination angles. We have 70% recovery up to a VR magnitude of 27, with strong constraints on the distance and ecliptic angle. The magnitude is well recovered, subject to a systematic bias from finite aperture photometry, and the matching distance between nights is typically 0.7 arcsec (3.5 pixels).Figure 1 shows preliminary recoveries of simulated data inserted into our Suprime-Cam fields. We are able 1) to recover objects to a VR magnitude of 28 with 40% completeness; 2) to estimate the distances of the recovered objects to an accuracy of about 1 AU; 3) to achieve a small scatter in magnitude, after accounting for a systematic light loss; 4) to recover the inclination of the orbit on a coarse 5 degree grid. We are still tuning the application of the technique to the actual data, and are working to remove remaining systematic biases.
![Other Projects](https://webarchive.library.unt.edu/eot2008/20090825161929im_/http://astrobiology.nasa.gov/img/text/hd_other_projects_sa.gif)
- HANDBOOK OF STAR FORMING REGIONS
- A Rare low mass quadruple spectroscopic AND eclipsing binary
- A search for Main Belt Comets in Pan-STARRS 1
- A search for primordial water from deep in the Earth's mantle
- A spectroscopically unique Main Belt asteroid: 10537 (1991 RY16)
- A Supertree Analysis of the Metazoan Phylogeny
- Acquisition and Installation of a new Cameca ims 1280 ion microprobe
- Acquisition and Installation of Witec Confocal Raman microscope scanning system
- Amorphization of Crystalline Water Ice in the Solar System
- Assessing the likelihood of supernova impact of protoplanetary disks
- Carbonate Lithologies on Devon Island, Canada
- Chemistry and biology of ultramafic-hosted alkaline springs
- Chemistry of the NH3/H2O system
- DIVERSITY AND BIOGEOGRAPHY OF THE UNIQUE TROPICAL PHYLUM PLACOZOA
- Dynamical Evolution of Astroid Belt and the Parent Bodies of Iron Meteorites
- Ecology of a Hawaiian lava cave microbial mat
- FMARS Long Duration Mission: a simulation of manned Mars exploration in an analogue environment, Devon Island, Canada
- Formation and Detection of Hot-Earth Objects in Systems with Close-in Jupiters
- Formation and the Prospects of the Detection of Habitable Planets in Extreme Planetary Systems
- Formation of Molecular Hydrogen via Interaction of Ionizing Radiation with Hydrocarbon Ices in the Interstellar Medium
- Formation of Planetesimals in a Dynamically Evolving Nebula
- FU ORIONIS ERUPTIONS
- Ice Ages on Mars
- Ice at the Mars Phoenix Landing Site
- Ice on Main Belt Comets
- Icelandic subglacial lakes
- Mechanisms of Marine Microbial Community Structuring
- Mechanistical Studies on the Non-Equilibrium Chemistry of Unusual Carbon Oxide in Solar System Ices
- Modeling grain surface reaction pathways for large organic molecules
- Molecular Deuteration on grain surfaces
- NEWBORN BINARIES
- Observations and Models of comet 17P/Holmes
- Origin and Activation Mechanism of Main Belt Comets
- Origin of Irregular Satellites
- Recovery of comet 85P/Boethin for the Deep Impact Extended Mission
- Sediment-buried basement deep biosphere
- Serpentinazation and abiogenic methane in the Mariana Forearc
- Sleeping through the Arctic Martian Sol
- Spectropolarimetric studies of stars with hot jupiters
- TES study of intracrater low albedo deposits, Amazonis Planitia, Mars
- The delivery of short-lived radionucleides to the solar system
- The effect of lunar-like satellites on the orbital infrared lightcurves of Earth-analog planets
- The Main Belt distribution of basaltic asteroids
- The Size Distribution of Small KBOs
- THE VYSOS PROJECT
- Ultra-violet processing of ices in the Rosette Nebula
- Unveiling the evolution and interplay of ice and gas in quiescent clouds
- Variable Young Stellar Objects Survey (VYSOS)
- Water on Mars
- X-ray- and UV-bright low-mass stars in the solar neighborhood