Fast Algorithms for Slow Moving Asteroids: Constraints on the Distribution of Kuiper Belt Objects

Abstract

We introduce a new computational technique for searching for faint moving sources in astronomical images. Starting from a maximum likelihood estimate for the probability of the detection of a source within a series of images, we develop a massively parallel algorithm for searching through candidate asteroid trajectories that utilizes Graphics Processing Units (GPU). This technique can search over 10 10 possible asteroid trajectories in stacks of the order 10-15 4K x 4K images in under a minute using a single consumer grade GPU. We apply this algorithm to data from the 2015 campaign of the High Cadence Transient Survey (HiTS) obtained with the Dark Energy Camera (DECam). We find 39 previously unknown Kuiper Belt Objects in the 150 square degrees of the survey. Comparing these asteroids to an existing model for the inclination distribution of the Kuiper Belt we demonstrate that we recover a KBO population above our detection limit consistent with previous studies. Software used in this analysis is made available as an open source package.

Probability of simultaneous parallax detection for free-floating planet microlensing events near Galactic Centre

“…In the real observation, there is the effect of the planetesimals and asteroids in the asteroid belt, Kuiper belt, and Oort cloud, and the flux interference by the stellar flares, transits of the source system, and binary-source events. The effect from asteroids is not negligible if the orbits scratch the line-of-sight of the event, and the same thing around the source star offers the flux noise (Trilling & Bernstein 2006;Usui et al 2013;Matthews et al 2014;Wong & Brown 2017;Whidden et al 2019). The stellar flares provide a sudden magnitude increase, and the followup observation with high cadence will be required to identify either a stellar flare or a short microlensing event from the light curve (Balona 2015).…”

Community Challenges in the Era of Petabyte-Scale Sky Surveys

“…For instance, open-source and community-supported implementations of advanced discovery and detection algorithms are necessary to enable discovery of solar system objects at scale in survey and archival data sets. Examples that are currently in development include THOR (Moeyens & Juric 2019), KBMOD (Whidden et al 2019), and HelioLinC (Holman et al 2018). Moreover, a survey-agnostic toolkit for rapid and basic asteroidal and cometary characterization (such as activity detection or taxonomic classification) could jump-start the scientific output of any telescope, survey, or data archive.…”

A New Blind Asteroid Detection Scheme

“…More recently, Shao et al (2014) and Zhai et al (2014) used this method for fast moving NEOs, and used it to search for MBAs. In the last year, authors have implemented faster searches with graphical processing units (GPUs) and massively parallel analyses capable of searching a finer grid and stacking a deeper stack of short exposures (Zhai et al 2019;Whidden et al 2019). Additionally, digital tracking has been used to estimate more precise astrometry, which is vital for fast moving objects for accurate orbit determination (Zhai 1 https://minorplanetcenter.net/data et al 2018).…”